Patent Application
20250220659
The present disclosure relates to a wireless communication system.
A variety of technologies, such as machine-to-machine (M2M) communication, machine type communication (MTC), and a variety of devices demanding high data throughput, such as smartphones and tablet personal computers (PCs), have emerged and spread. Accordingly, the volume of data throughput demanded to be processed in a cellular network has rapidly increased. In order to satisfy such rapidly increasing data throughput, carrier aggregation technology or cognitive radio technology for efficiently employing more frequency bands and multiple input multiple output (MIMO) technology or multi-base station (BS) cooperation technology for raising data capacity transmitted on limited frequency resources have been developed.
As more and more communication devices have required greater communication capacity, there has been a need for enhanced mobile broadband (eMBB) communication relative to legacy radio access technology (RAT). In addition, massive machine type communication (mMTC) for providing various services at anytime and anywhere by connecting a plurality of devices and objects to each other is one main issue to be considered in next-generation communication.
Communication system design considering services/user equipment (UEs) sensitive to reliability and latency is also under discussion. The introduction of next-generation RAT is being discussed in consideration of eMBB communication, mMTC, ultra-reliable and low-latency communication (URLLC), and the like.
As new radio communication technology has been introduced, the number of UEs to which a BS should provide services in a prescribed resource region is increasing and the volume of data and control information that the BS transmits/receives to/from the UEs to which the BS provides services is also increasing. Since the amount of resources available to the BS for communication with the UE(s) is limited, a new method for the BS to efficiently receive/transmit uplink/downlink data and/or uplink/downlink control information from/to the UE(s) using the limited radio resources is needed. In other words, due to increase in the density of nodes and/or the density of UEs, a method for efficiently using high-density nodes or high-density UEs for communication is needed.
A method to efficiently support various services with different requirements in a wireless communication system is also needed.
Overcoming delay or latency is an important challenge to applications, performance of which is sensitive to delay/latency.
Further, a method of efficiently transmitting data packets in which jitter may occur in a wireless communication system is needed.
The objects to be achieved with the present disclosure are not limited to what has been particularly described hereinabove and other objects not described herein will be more clearly understood by persons skilled in the art from the following detailed description.
In an aspect of the present disclosure, provided herein is a method of receiving a downlink signal by a user equipment (UE) in a wireless communication system. The method includes: receiving a plurality of semi-persistent scheduling (SPS) configurations for a cell, wherein each of the plurality of SPS configurations is related to a downlink assignment occurring with a specific periodicity; receiving pattern configuration information regarding at least one activation pattern indicating activation or deactivation of each of a plurality of downlink assignments occurring within a specific period, based on the plurality of SPS configurations; determining SPS physical downlink shared channel (PDSCH) occasions based on the plurality of SPS configurations and the pattern configuration information; and receiving a PDSCH within the SPS PDSCH occasions.
In another aspect of the present disclosure, provided herein is a UE configured to receive a downlink signal in a wireless communication system. The UE includes: at least one transceiver; at least one processor; and at least one computer memory operably connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations. The operations include: receiving a plurality of SPS configurations for a cell, wherein each of the plurality of SPS configurations is related to a downlink assignment occurring with a specific periodicity; receiving pattern configuration information regarding at least one activation pattern indicating activation or deactivation of each of a plurality of downlink assignments occurring within a specific period, based on the plurality of SPS configurations; determining SPS PDSCH occasions based on the plurality of SPS configurations and the pattern configuration information; and receiving a PDSCH within the SPS PDSCH occasions.
In another aspect of the present disclosure, provided herein is a processing device in a wireless communication system. The processing device includes: at least one processor; and at least one computer memory operably connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations. The operations include: receiving a plurality of SPS configurations for a cell, wherein each of the plurality of SPS configurations is related to a downlink assignment occurring with a specific periodicity; receiving pattern configuration information regarding at least one activation pattern indicating activation or deactivation of each of a plurality of downlink assignments occurring within a specific period, based on the plurality of SPS configurations; determining SPS PDSCH occasions based on the plurality of SPS configurations and the pattern configuration information; and receiving a PDSCH within the SPS PDSCH occasions.
In another aspect of the present disclosure, provided herein is a computer-readable storage medium configured to store at least one program code including instructions that, when executed, cause at least one processor to perform operations. The operations include: receiving a plurality of SPS configurations for a cell, wherein each of the plurality of SPS configurations is related to a downlink assignment occurring with a specific periodicity; receiving pattern configuration information regarding at least one activation pattern indicating activation or deactivation of each of a plurality of downlink assignments occurring within a specific period, based on the plurality of SPS configurations; determining SPS PDSCH occasions based on the plurality of SPS configurations and the pattern configuration information; and receiving a PDSCH within the SPS PDSCH occasions.
In another aspect of the present disclosure, provided herein is a method of transmitting, by a base station (BS), a downlink signal to a UE in a wireless communication system. The method includes: transmitting a plurality of SPS configurations for a cell, wherein each of the plurality of SPS configurations is related to a downlink assignment occurring with a specific periodicity; transmitting pattern configuration information regarding at least one activation pattern indicating activation or deactivation of each of a plurality of downlink assignments occurring within a specific period, based on the plurality of SPS configurations; determining SPS PDSCH occasions based on the plurality of SPS configurations and the pattern configuration information; and transmitting a PDSCH within the SPS PDSCH occasions.
In a further aspect of the present disclosure, provided herein is a BS configured to transmit a downlink signal to a UE in a wireless communication system. The BS includes: at least one processor; and at least one computer memory operably connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations. The operations include: transmitting a plurality of SPS configurations for a cell, wherein each of the plurality of SPS configurations is related to a downlink assignment occurring with a specific periodicity; transmitting pattern configuration information regarding at least one activation pattern indicating activation or deactivation of each of a plurality of downlink assignments occurring within a specific period, based on the plurality of SPS configurations; determining SPS PDSCH occasions based on the plurality of SPS configurations and the pattern configuration information; and transmitting a PDSCH within the SPS PDSCH occasions.
In each aspect of the present disclosure, the pattern configuration information may include information regarding a plurality of different activation patterns.
In each aspect of the present disclosure, determining the SPS PDSCH occasions based on the plurality of SPS configurations and the pattern configuration information may include determining the SPS PDSCH occasions by applying a first activation pattern among the plurality of activation patterns based on a predetermined condition being satisfied.
In each aspect of the present disclosure, regarding the method for the UE or the operations of the processing device, the storage medium, or the UE, the predetermined condition may include receiving the PDSCH at an SPS PDSCH occasion determined based on a second activation pattern among the plurality of activation patterns.
In each aspect of the present disclosure, regarding the method for the BS or the operations of the BS, the predetermined condition may include transmitting the PDSCH at an SPS PDSCH occasion determined based on a second activation pattern among the plurality of activation patterns.
In each aspect of the present disclosure, regarding the method for the UE or the operations of the processing device, the storage medium, or the UE, the predetermined condition may include receiving downlink control information (DCI) including indication information regarding the first activation pattern among the plurality of activation patterns.
In each aspect of the present disclosure, regarding the method for the BS or the operations of the BS, the predetermined conditions may include transmitting DCI including indication information regarding the first activation pattern among the plurality of activation patterns.
In each aspect of the present disclosure, the method for the UE or the operations of the processing device, the storage medium, or the UE may include: generating a hybrid automatic repeat request acknowledgment (HARQ-ACK) codebook including a HARQ-ACK information bit for the PDSCH based on the reception of the PDSCH; and transmitting the HARQ-ACK codebook in a slot related to an SPS PDSCH occasion at which the PDSCH is received.
In each aspect of the present disclosure, the method for the BS or the operations of the BS may include receiving a HARQ-ACK codebook including a HARQ-ACK information bit for the PDSCH in a slot related to an SPS PDSCH occasion at which the PDSCH is transmitted, based on the transmission of the PDSCH.
In each aspect of the present disclosure, the HARQ-ACK codebook may exclude HARQ-ACK information corresponding to an SPS PDSCH occasion not activated by the activation pattern among SPS PDSCH occasions corresponding to the plurality of downlink assignments.
In each aspect of the present disclosure, the method for the UE or the operations of the processing device, the storage medium, or the UE may further include: receiving respective activation physical downlink control channels (PDCCHs) for the plurality of SPS configurations.
In each aspect of the present disclosure, the method for the BS or the operations of the BS may include transmitting respective activation PDCCHs for the plurality of SPS configurations.
In each aspect of the present disclosure, the pattern configuration information may be based on SPS configurations activated by the activation PDCCHs.
The foregoing solutions are merely a part of the examples of the present disclosure and various examples into which the technical features of the present disclosure are incorporated may be derived and understood by persons skilled in the art from the following detailed description.
According to some implementations of the present disclosure, a wireless communication signal may be efficiently transmitted/received. Accordingly, the total throughput of a wireless communication system may be raised.
According to some implementations of the present disclosure, various services with different requirements may be efficiently supported in a wireless communication system.
According to some implementations of the present disclosure, delay/latency generated during radio communication between communication devices may be reduced.
According to some implementations of the present disclosure, a plurality of semi-static configurations may be activated/deactivated at once.
According to some implementations of the present disclosure, various resource(s) may be allocated with no or low latency.
According to some implementations of the present disclosure, switching between multiple semi-static configuration groups may be supported via a single signal.
The effects according to the present disclosure are not limited to what has been particularly described hereinabove and other effects not described herein will be more clearly understood by persons skilled in the art related to the present disclosure from the following detailed description.
The accompanying drawings, which are included to provide a further understanding of the present disclosure, illustrate examples of implementations of the present disclosure and together with the detailed description serve to explain implementations of the present disclosure:
Hereinafter, implementations according to the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description, which will be given below with reference to the accompanying drawings, is intended to explain exemplary implementations of the present disclosure, rather than to show the only implementations that may be implemented according to the present disclosure. The following detailed description includes specific details in order to provide a thorough understanding of the present disclosure. However, it will be apparent to those skilled in the art that the present disclosure may be practiced without such specific details.
In some instances, known structures and devices may be omitted or may be shown in block diagram form, focusing on important features of the structures and devices, so as not to obscure the concept of the present disclosure. The same reference numbers will be used throughout the present disclosure to refer to the same or like parts.
A technique, a device, and a system described below may be applied to a variety of wireless multiple access systems. The multiple access systems may include, for example, a code division multiple access (CDMA) system, a frequency division multiple access (FDMA) system, a time division multiple access (TDMA) system, an orthogonal frequency division multiple access (OFDMA) system, a single-carrier frequency division multiple access (SC-FDMA) system, a multi-carrier frequency division multiple access (MC-FDMA) system, etc. CDMA may be implemented by radio technology such as universal terrestrial radio access (UTRA) or CDMA2000. TDMA may be implemented by radio technology such as global system for mobile communications (GSM), general packet radio service (GPRS), enhanced data rates for GSM evolution (EDGE) (i.e., GERAN), etc. OFDMA may be implemented by radio technology such as institute of electrical and electronics engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, evolved-UTRA (E-UTRA), etc. UTRA is part of universal mobile telecommunications system (UMTS) and 3rd generation partnership project (3GPP) long-term evolution (LTE) is part of E-UMTS using E-UTRA. 3GPP LTE adopts OFDMA on downlink (DL) and adopts SC-FDMA on uplink (UL). LTE-advanced (LTE-A) is an evolved version of 3GPP LTE.
For convenience of description, description will be given under the assumption that the present disclosure is applied to LTE and/or new RAT (NR). However, the technical features of the present disclosure are not limited thereto. For example, although the following detailed description is given based on mobile communication systems corresponding to 3GPP LTE/NR systems, the mobile communication systems are applicable to other arbitrary mobile communication systems except for matters that are specific to the 3GPP LTE/NR system.
For terms and techniques that are not described in detail among terms and techniques used in the present disclosure, reference may be made to 3GPP based standard specifications, for example, 3GPP TS 36.211, 3GPP TS 36.212, 3GPP TS 36.213, 3GPP TS 36.321, 3GPP TS 36.300, 3GPP TS 36.331, 3GPP TS 37.213, 3GPP TS 38.211, 3GPP TS 38.212, 3GPP TS 38.213, 3GPP TS 38.214, 3GPP TS 38.300, 3GPP TS 38.321, 3GPP TS 38.331, etc.
In examples of the present disclosure described later, if a device “assumes” something, this may mean that a channel transmission entity transmits a channel in compliance with the corresponding “assumption”. This also may mean that a channel reception entity receives or decodes the channel in the form of conforming to the “assumption” on the premise that the channel has been transmitted in compliance with the “assumption”.
In the present disclosure, a user equipment (UE) may be fixed or mobile. Each of various devices that transmit and/or receive user data and/or control information by communicating with a base station (BS) may be the UE. The term UE may be referred to as terminal equipment, mobile station (MS), mobile terminal (MT), user terminal (UT), subscriber station (SS), wireless device, personal digital assistant (PDA), wireless modem, handheld device, etc. In the present disclosure, a BS refers to a fixed station that communicates with a UE and/or another BS and exchanges data and control information with a UE and another BS. The term BS may be referred to as advanced base station (ABS), Node-B (NB), evolved Node-B (eNB), base transceiver system (BTS), access point (AP), processing server (PS), etc. Particularly, a BS of a universal terrestrial radio access (UTRAN) is referred to as an NB, a BS of an evolved-UTRAN (E-UTRAN) is referred to as an eNB, and a BS of new radio access technology network is referred to as a gNB. Hereinbelow, for convenience of description, the NB, eNB, or gNB will be referred to as a BS regardless of the type or version of communication technology.
In the present disclosure, a node refers to a fixed point capable of transmitting/receiving a radio signal to/from a UE by communication with the UE. Various types of BSs may be used as nodes regardless of the names thereof. For example, a BS, NB, eNB, pico-cell eNB (PeNB), home eNB (HeNB), relay, repeater, etc. may be a node. Furthermore, a node may not be a BS. For example, a radio remote head (RRH) or a radio remote unit (RRU) may be a node. Generally, the RRH and RRU have power levels lower than that of the BS. Since the RRH or RRU (hereinafter, RRH/RRU) is connected to the BS through a dedicated line such as an optical cable in general, cooperative communication according to the RRH/RRU and the BS may be smoothly performed relative to cooperative communication according to BSs connected through a wireless link. At least one antenna is installed per node. An antenna may refer to a physical antenna port or refer to a virtual antenna or an antenna group. The node may also be called a point.
In the present disclosure, a cell refers to a specific geographical area in which one or more nodes provide communication services. Accordingly, in the present disclosure, communication with a specific cell may mean communication with a BS or a node providing communication services to the specific cell. A DL/UL signal of the specific cell refers to a DL/UL signal from/to the BS or the node providing communication services to the specific cell. A cell providing UL/DL communication services to a UE is especially called a serving cell. Furthermore, channel status/quality of the specific cell refers to channel status/quality of a channel or a communication link generated between the BS or the node providing communication services to the specific cell and the UE. In 3GPP-based communication systems, the UE may measure a DL channel state from a specific node using cell-specific reference signal(s) (CRS(s)) transmitted on a CRS resource and/or channel state information reference signal(s) (CSI-RS(s)) transmitted on a CSI-RS resource, allocated to the specific node by antenna port(s) of the specific node.
A 3GPP-based communication system uses the concept of a cell in order to manage radio resources, and a cell related with the radio resources is distinguished from a cell of a geographic area.
The “cell” of the geographic area may be understood as coverage within which a node may provide services using a carrier, and the “cell” of the radio resources is associated with bandwidth (BW), which is a frequency range configured by the carrier. Since DL coverage, which is a range within which the node is capable of transmitting a valid signal, and UL coverage, which is a range within which the node is capable of receiving the valid signal from the UE, depend upon a carrier carrying the signal, coverage of the node may also be associated with coverage of the “cell” of radio resources used by the node. Accordingly, the term “cell” may be used to indicate service coverage by the node sometimes, radio resources at other times, or a range that a signal using the radio resources may reach with valid strength at other times.
In 3GPP communication standards, the concept of the cell is used in order to manage radio resources. The “cell” associated with the radio resources is defined by a combination of DL resources and UL resources, that is, a combination of a DL component carrier (CC) and a UL CC. The cell may be configured by the DL resources only or by the combination of the DL resources and the UL resources. If carrier aggregation is supported, linkage between a carrier frequency of the DL resources (or DL CC) and a carrier frequency of the UL resources (or UL CC) may be indicated by system information. For example, the combination of the DL resources and the UL resources may be indicated by system information block type 2 (SIB2) linkage. In this case, the carrier frequency may be equal to or different from a center frequency of each cell or CC. When carrier aggregation (CA) is configured, the UE has only one radio resource control (RRC) connection with a network. During RRC connection establishment/re-establishment/handover, one serving cell provides non-access stratum (NAS) mobility information. During RRC connection re-establishment/handover, one serving cell provides security input. This cell is referred to as a primary cell (Pcell). The Pcell refers to a cell operating on a primary frequency on which the UE performs an initial connection establishment procedure or initiates a connection re-establishment procedure. According to UE capability, secondary cells (Scells) may be configured to form a set of serving cells together with the Pcell. The Scell may be configured after completion of RRC connection establishment and used to provide additional radio resources in addition to resources of a specific cell (SpCell). A carrier corresponding to the Pcell on DL is referred to as a downlink primary CC (DL PCC), and a carrier corresponding to the Pcell on UL is referred to as an uplink primary CC (UL PCC). A carrier corresponding to the Scell on DL is referred to as a downlink secondary CC (DL SCC), and a carrier corresponding to the Scell on UL is referred to as an uplink secondary CC (UL SCC).
In a dual connectivity (DC) operation, the term special cell (SpCell) refers to a Pcell of a master cell group (MCG) or a primary secondary cell (PSCell) of a secondary cell group (SCG). The SpCell supports PUCCH transmission and contention-based random access and is always activated. The MCG is a group of service cells associated with a master node (e.g., BS) and includes the SpCell (Pcell) and optionally one or more Scells. For a UE configured with DC, the SCG is a subset of serving cells associated with a secondary node and includes the PSCell and 0 or more Scells. The PSCell is a primary Scell of the SCG. For a UE in RRC_CONNECTED state, which is not configured with CA or DC, only one serving cell including only the Pcell is present. For a UE in RRC_CONNECTED state, which is configured with CA or DC, the term serving cells refers to a set of cells including SpCell(s) and all Scell(s). In DC, two medium access control (MAC) entities, i.e., one MAC entity for the MCG and one MAC entity for the SCG, are configured for the UE.
For a UE that is configured with CA and is not configured with DC, a Pcell PUCCH group (also called a primary PUCCH group) including the Pcell and 0 or more Scells and an Scell PUCCH group (also called a secondary PUCCH group) including only Scell(s) may be configured. For the Scell, an Scell on which a PUCCH associated with the corresponding cell is transmitted (hereinafter, a PUCCH cell) may be configured. An Scell for which a PUCCH Scell is indicated belongs to the Scell PUCCH group (i.e., the secondary PUCCH group) and PUCCH transmission of related uplink control information (UCI) is performed on the PUCCH Scell. If a PUCCH Scell is not indicated for an Scell or a cell which is indicated for PUCCH transmission for the Scell is a Pcell, the Scell belongs to the Pcell PUCCH group (i.e., the primary PUCCH group) and PUCCH transmission of related UCI is performed on the Pcell. Hereinbelow, if the UE is configured with the SCG and some implementations of the present disclosure related to a PUCCH are applied to the SCG, the primary cell may refer to the PSCell of the SCG. If the UE is configured with the PUCCH Scell and some implementations of the present disclosure related to the PUCCH are applied to the secondary PUCCH group, the primary cell may refer to the PUCCH Scell of the secondary PUCCH group.
In a wireless communication system, the UE receives information on DL from the BS and the UE transmits information on UL to the BS. The information that the BS and UE transmit and/or receive includes data and a variety of control information and there are various physical channels according to types/usage of the information that the UE and the BS transmit and/or receive.
The 3GPP-based communication standards define DL physical channels corresponding to resource elements carrying information originating from a higher layer and DL physical signals corresponding to resource elements which are used by the physical layer but do not carry the information originating from the higher layer. For example, a physical downlink shared channel (PDSCH), a physical broadcast channel (PBCH), a physical multicast channel (PMCH), a physical control format indicator channel (PCFICH), a physical downlink control channel (PDCCH), etc. are defined as the DL physical channels, and a reference signal (RS) and a synchronization signal (SS) are defined as the DL physical signals. The RS, which is also referred to as a pilot, represents a signal with a predefined special waveform known to both the BS and the UE. For example, a demodulation reference signal (DMRS), a channel state information RS (CSI-RS), etc. are defined as DL RSs. The 3GPP-based communication standards define UL physical channels corresponding to resource elements carrying information originating from the higher layer and UL physical signals corresponding to resource elements which are used by the physical layer but do not carry the information originating from the higher layer. For example, a physical uplink shared channel (PUSCH), a physical uplink control channel (PUCCH), and a physical random access channel (PRACH) are defined as the UL physical channels, and a DMRS for a UL control/data signal, a sounding reference signal (SRS) used for UL channel measurement, etc. are defined.
In the present disclosure, a PDCCH refers to a set of time-frequency resources (e.g., resource elements (REs)) carrying downlink control information (DCI), and a PDSCH refers to a set of time-frequency resources carrying DL data. A PUCCH, a PUSCH, and a PRACH refer to a set of time-frequency resources carrying UCI, a set of time-frequency resources carrying UL data, and a set of time-frequency resources carrying random access signals, respectively. In the following description, “the UE transmits/receives a PUCCH/PUSCH/PRACH” is used as the same meaning that the UE transmits/receives the UCI/UL data/random access signals on or through the PUCCH/PUSCH/PRACH, respectively. In addition, “the BS transmits/receives a PBCH/PDCCH/PDSCH” is used as the same meaning that the BS transmits the broadcast information/DCI/DL data on or through a PBCH/PDCCH/PDSCH, respectively.
In this specification, a radio resource (e.g., a time-frequency resource) scheduled or configured to the UE by the BS for transmission or reception of the PUCCH/PUSCH/PDSCH may be referred to as a PUCCH/PUSCH/PDSCH resource.
Since a communication device receives a synchronization signal block (SSB), DMRS, CSI-RS, PBCH, PDCCH, PDSCH, PUSCH, and/or PUCCH in the form of radio signals on a cell, the communication device may not select and receive radio signals including only a specific physical channel or a specific physical signal through a radio frequency (RF) receiver, or may not select and receive radio signals without a specific physical channel or a specific physical signal through the RF receiver. In actual operations, the communication device receives radio signals on the cell via the RF receiver, converts the radio signals, which are RF band signals, into baseband signals, and then decodes physical signals and/or physical channels in the baseband signals using one or more processors. Thus, in some implementations of the present disclosure, not receiving physical signals and/or physical channels may mean that a communication device does not attempt to restore the physical signals and/or physical channels from radio signals, for example, does not attempt to decode the physical signals and/or physical channels, rather than that the communication device does not actually receive the radio signals including the corresponding physical signals and/or physical channels.
As more and more communication devices have required greater communication capacity, there has been a need for eMBB communication relative to legacy radio access technology (RAT). In addition, massive MTC for providing various services at anytime and anywhere by connecting a plurality of devices and objects to each other is one main issue to be considered in next-generation communication. Further, communication system design considering services/UEs sensitive to reliability and latency is also under discussion. The introduction of next-generation RAT is being discussed in consideration of eMBB communication, massive MTC, ultra-reliable and low-latency communication (URLLC), and the like. Currently, in 3GPP, a study on the next-generation mobile communication systems after EPC is being conducted. In the present disclosure, for convenience, the corresponding technology is referred to as a new RAT (NR) or fifth-generation (5G) RAT, and a system using NR or supporting NR is referred to as an NR system.
The wireless devices 100a to 100f may be connected to a network 300 via BSs 200. AI technology may be applied to the wireless devices 100a to 100f and the wireless devices 100a to 100f may be connected to the AI server 400 via the network 300. The network 300 may be configured using a 3G network, a 4G (e.g., LTE) network, or a 5G (e.g., NR) network. Although the wireless devices 100a to 100f may communicate with each other through the BSs 200/network 300, the wireless devices 100a to 100f may perform direct communication (e.g., sidelink communication) with each other without passing through the BSs/network. For example, the vehicles 100b-1 and 100b-2 may perform direct communication (e.g., vehicle-to-vehicle (V2V)/Vehicle-to-everything (V2X) communication). The IoT device (e.g., a sensor) may perform direct communication with other IoT devices (e.g., sensors) or other wireless devices 100a to 100f.
Wireless communication/connections 150a and 150b may be established between the wireless devices 100a to 100f and the BSs 200 and between the wireless devices 100a to 100f). Here, the wireless communication/connections such as UL/DL communication 150a and sidelink communication 150b (or, device-to-device (D2D) communication) may be established by various RATs (e.g., 5G NR). The wireless devices and the BSs/wireless devices may transmit/receive radio signals to/from each other through the wireless communication/connections 150a and 150b. To this end, at least a part of various configuration information configuring processes, various signal processing processes (e.g., channel encoding/decoding, modulation/demodulation, and resource mapping/demapping), and resource allocating processes, for transmitting/receiving radio signals, may be performed based on the various proposals of the present disclosure.
The first wireless device 100 may include one or more processors 102 and one or more memories 104 and additionally further include one or more transceivers 106 and/or one or more antennas 108. The processor(s) 102 may control the memory(s) 104 and/or the transceiver(s) 106 and may be configured to implement the below-described/proposed functions, procedures, and/or methods. For example, the processor(s) 102 may process information within the memory(s) 104 to generate first information/signals and then transmit radio signals including the first information/signals through the transceiver(s) 106. The processor(s) 102 may receive radio signals including second information/signals through the transceiver(s) 106 and then store information obtained by processing the second information/signals in the memory(s) 104. The memory(s) 104 may be connected to the processor(s) 102 and may store a variety of information related to operations of the processor(s) 102. For example, the memory(s) 104 may perform a part or all of processes controlled by the processor(s) 102 or store software code including instructions for performing the below-described/proposed procedures and/or methods. Here, the processor(s) 102 and the memory(s) 104 may be a part of a communication modem/circuit/chip designed to implement RAT (e.g., LTE or NR). The transceiver(s) 106 may be connected to the processor(s) 102 and transmit and/or receive radio signals through one or more antennas 108. Each of the transceiver(s) 106 may include a transmitter and/or a receiver. The transceiver(s) 106 is used interchangeably with radio frequency (RF) unit(s). In the present disclosure, the wireless device may represent the communication modem/circuit/chip.
The second wireless device 200 may include one or more processors 202 and one or more memories 204 and additionally further include one or more transceivers 206 and/or one or more antennas 208. The processor(s) 202 may control the memory(s) 204 and/or the transceiver(s) 206 and may be configured to implement the below-described/proposed functions, procedures, and/or methods. For example, the processor(s) 202 may process information within the memory(s) 204 to generate third information/signals and then transmit radio signals including the third information/signals through the transceiver(s) 206. The processor(s) 202 may receive radio signals including fourth information/signals through the transceiver(s) 106 and then store information obtained by processing the fourth information/signals in the memory(s) 204. The memory(s) 204 may be connected to the processor(s) 202 and may store a variety of information related to operations of the processor(s) 202. For example, the memory(s) 204 may perform a part or all of processes controlled by the processor(s) 202 or store software code including instructions for performing the below-described/proposed procedures and/or methods. Here, the processor(s) 202 and the memory(s) 204 may be a part of a communication modem/circuit/chip designed to implement RAT (e.g., LTE or NR). The transceiver(s) 206 may be connected to the processor(s) 202 and transmit and/or receive radio signals through one or more antennas 208. Each of the transceiver(s) 206 may include a transmitter and/or a receiver. The transceiver(s) 206 is used interchangeably with RF unit(s). In the present disclosure, the wireless device may represent the communication modem/circuit/chip.
The wireless communication technology implemented in the wireless devices 100 and 200 of the present disclosure may include narrowband Internet of things for low-power communication as well as LTE, NR, and 6G. For example, the NB-IoT technology may be an example of low-power wide-area network (LPWAN) technologies and implemented in standards such as LTE Cat NB1 and/or LTE Cat NB2. However, the NB-IoT technology is not limited to the above names. Additionally or alternatively, the wireless communication technology implemented in the wireless devices XXX and YYY of the present disclosure may perform communication based on the LTE-M technology. For example, the LTE-M technology may be an example of LPWAN technologies and called by various names including enhanced machine type communication (eMTC). For example, the LTE-M technology may be implemented in at least one of the following various standards: 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-Bandwidth Limited (non-BL), 5) LTE-MTC, 6) LTE Machine Type Communication, and/or 7) LTE M, etc., but the LTE-M technology is not limited to the above names. Additionally or alternatively, the wireless communication technology implemented in the wireless devices XXX and YYY of the present disclosure may include at least one of ZigBee, Bluetooth, and LPWAN in consideration of low-power communication, but the wireless communication technology is not limited to the above names. For example, the ZigBee technology may create a personal area network (PAN) related to small/low-power digital communication based on various standards such as IEEE 802.15.4 and so on, and the ZigBee technology may be called by various names.
Hereinafter, hardware elements of the wireless devices 100 and 200 will be described more specifically. One or more protocol layers may be implemented by, without being limited to, one or more processors 102 and 202. For example, the one or more processors 102 and 202 may implement one or more layers (e.g., functional layers such as a physical (PHY) layer, medium access control (MAC) layer, a radio link control (RLC) layer, a packet data convergence protocol (PDCP) layer, radio resource control (RRC) layer, and a service data adaptation protocol (SDAP) layer). The one or more processors 102 and 202 may generate one or more protocol data units (PDUs) and/or one or more service data units (SDUs) according to the functions, procedures, proposals, and/or methods disclosed in the present disclosure. The one or more processors 102 and 202 may generate messages, control information, data, or information according to the functions, procedures, proposals, and/or methods disclosed in the present disclosure. The one or more processors 102 and 202 may generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information according to the functions, procedures, proposals, and/or methods disclosed in the present disclosure and provide the generated signals to the one or more transceivers 106 and 206. The one or more processors 102 and 202 may receive the signals (e.g., baseband signals) from the one or more transceivers 106 and 206 and acquire the PDUs, SDUs, messages, control information, data, or information according to the functions, procedures, proposals, and/or methods disclosed in the present disclosure.
The one or more processors 102 and 202 may be referred to as controllers, microcontrollers, microprocessors, or microcomputers. The one or more processors 102 and 202 may be implemented by hardware, firmware, software, or a combination thereof. As an example, one or more application specific integrated circuits (ASICs), one or more digital signal processors (DSPs), one or more digital signal processing devices (DSPDs), one or more programmable logic devices (PLDs), or one or more field programmable gate arrays (FPGAs) may be included in the one or more processors 102 and 202. The functions, procedures, proposals, and/or methods disclosed in the present disclosure may be implemented using firmware or software, and the firmware or software may be configured to include the modules, procedures, or functions. Firmware or software configured to perform the functions, procedures, proposals, and/or methods disclosed in the present disclosure may be included in the one or more processors 102 and 202 or stored in the one or more memories 104 and 204 so as to be driven by the one or more processors 102 and 202. The functions, procedures, proposals, and/or methods disclosed in the present disclosure may be implemented using firmware or software in the form of code, commands, and/or a set of commands.
The one or more memories 104 and 204 may be connected to the one or more processors 102 and 202 and store various types of data, signals, messages, information, programs, code, commands, and/or instructions. The one or more memories 104 and 204 may be configured by read-only memories (ROMs), random access memories (RAMs), electrically erasable programmable read-only memories (EPROMs), flash memories, hard drives, registers, cash memories, computer-readable storage media, and/or combinations thereof. The one or more memories 104 and 204 may be located at the interior and/or exterior of the one or more processors 102 and 202. The one or more memories 104 and 204 may be connected to the one or more processors 102 and 202 through various technologies such as wired or wireless connection.
The one or more transceivers 106 and 206 may transmit user data, control information, and/or radio signals/channels, mentioned in the methods and/or operational flowcharts of the present disclosure, to one or more other devices. The one or more transceivers 106 and 206 may receive user data, control information, and/or radio signals/channels, mentioned in the functions, procedures, proposals, methods, and/or operational flowcharts disclosed in the present disclosure, from one or more other devices. For example, the one or more transceivers 106 and 206 may be connected to the one or more processors 102 and 202 and transmit and receive radio signals. For example, the one or more processors 102 and 202 may perform control so that the one or more transceivers 106 and 206 may transmit user data, control information, or radio signals to one or more other devices. The one or more processors 102 and 202 may perform control so that the one or more transceivers 106 and 206 may receive user data, control information, or radio signals from one or more other devices. The one or more transceivers 106 and 206 may be connected to the one or more antennas 108 and 208. The one or more transceivers 106 and 206 may be configured to transmit and receive user data, control information, and/or radio signals/channels, mentioned in the functions, procedures, proposals, methods, and/or operational flowcharts disclosed in the present disclosure, through the one or more antennas 108 and 208. In the present disclosure, the one or more antennas may be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports). The one or more transceivers 106 and 206 may convert received radio signals/channels etc. from RF band signals into baseband signals in order to process received user data, control information, radio signals/channels, etc. using the one or more processors 102 and 202. The one or more transceivers 106 and 206 may convert the user data, control information, radio signals/channels, etc. processed using the one or more processors 102 and 202 from the base band signals into the RF band signals. To this end, the one or more transceivers 106 and 206 may include (analog) oscillators and/or filters.
The additional components 140 may be variously configured according to types of wireless devices. For example, the additional components 140 may include at least one of a power unit/battery, input/output (I/O) unit, a driving unit, and a computing unit. The wireless device may be implemented in the form of, without being limited to, the robot (100a of FIG. 1), the vehicles (100b-1 and 100b-2 of
In
In the present disclosure, the at least one memory (e.g., 104 or 204) may store instructions or programs, and the instructions or programs may cause, when executed, at least one processor operably connected to the at least one memory to perform operations according to some embodiments or implementations of the present disclosure.
In the present disclosure, a computer readable (non-transitory) storage medium may store at least one instruction or program, and the at least one instruction or program may cause, when executed by at least one processor, the at least one processor to perform operations according to some embodiments or implementations of the present disclosure.
In the present disclosure, a processing device or apparatus may include at least one processor, and at least one computer memory operably connected to the at least one processor. The at least one computer memory may store instructions or programs, and the instructions or programs may cause, when executed, the at least one processor operably connected to the at least one memory to perform operations according to some embodiments or implementations of the present disclosure.
In the present disclosure, a computer program may include program code stored on at least one computer-readable (non-transitory) storage medium and, when executed, configured to perform operations according to some implementations of the present disclosure or cause at least one processor to perform the operations according to some implementations of the present disclosure. The computer program may be provided in the form of a computer program product. The computer program product may include at least one computer-readable (non-transitory) storage medium.
A communication device of the present disclosure includes at least one processor; and at least one computer memory operably connected to the at least one processor and configured to store instructions for causing, when executed, the at least one processor to perform operations according to example(s) of the present disclosure described later.
The frame structure of
Referring to
The table below shows the number of OFDM symbols per slot, the number of slots per frame, and the number of slots per subframe, according to the subcarrier spacing Δf=2u*15 KHz.
For a subcarrier spacing configuration u, slots may be indexed within a subframe in ascending order as follows: nus∈{0, . . . , nsubrame,uslot−1} and indexed within a frame in ascending order as follows: nus,f∈{0, . . . , nframe,uslot−1}.
For each serving cell in a set of DL BWPs or UL BWPs, the network may configure at least an initial DL BWP and one (if the serving cell is configured with uplink) or two (if supplementary uplink is used) initial UL BWPs. The network may configure additional UL and DL BWPs. For each DL BWP or UL BWP, the UE may be provided the following parameters for the serving cell: i) an SCS; ii) a CP; iii) a CRB NstartBWP=Ocarrier+RBstart and the number of contiguous RBs NsizeBWP=LRB provided by an RRC parameter locationAndBandwidth, which indicates an offset RBset and a length LRB as a resource indicator value (RIV) on the assumption of NstartBWP=275, and a value Ocarrier provided by an RRC parameter offsetToCarrier for the SCS; an index in the set of DL BWPs or UL BWPs; a set of BWP-common parameters; and a set of BWP-dedicated parameters.
Virtual resource blocks (VRBs) may be defined within the BWP and indexed from 0 to Nsize,uBWP,i−1, where i denotes a BWP number. The VRBs may be mapped to PRBs according to interleaved mapping or non-interleaved mapping. In some implementations, VRB n may be mapped to PRB n for non-interleaved VRB-to-PRB mapping.
The UE for which carrier aggregation is configured may be configured to use one or more cells. If the UE is configured with a plurality of serving cells, the UE may be configured with one or multiple cell groups. The UE may also be configured with a plurality of cell groups associated with different BSs. Alternatively, the UE may be configured with a plurality of cell groups associated with a single BS. Each cell group of the UE includes one or more serving cells and includes a single PUCCH cell for which PUCCH resources are configured. The PUCCH cell may be a Pcell or an Scell configured as the PUCCH cell among Scells of a corresponding cell group. Each serving cell of the UE belongs to one of cell groups of the UE and does not belong to a plurality of cells.
NR frequency bands are defined as two types of frequency ranges, i.e., FR1 and FR2. FR2 is also referred to as millimeter wave (mmW). The following table shows frequency ranges within which NR may operate.
Hereinafter, physical channels that may be used in the 3GPP-based wireless communication system will be described in detail.
A PDCCH carries DCI. For example, the PDCCH (i.e., DCI) carries information about transport format and resource allocation of a downlink shared channel (DL-SCH), information about resource allocation of an uplink shared channel (UL-SCH), paging information about a paging channel (PCH), system information about the DL-SCH, information about resource allocation for a control message, such as a random access response (RAR) transmitted on a PDSCH, of a layer (hereinafter, higher layer) positioned higher than a physical layer among protocol stacks of the UE/BS, a transmit power control command, information about activation/deactivation of configured scheduling (CS), etc. DCI including resource allocation information on the DL-SCH is called PDSCH scheduling DCI, and DCI including resource allocation information on the UL-SCH is called PUSCH scheduling DCI. The DCI includes a cyclic redundancy check (CRC). The CRC is masked/scrambled with various identifiers (e.g., radio network temporary identifier (RNTI)) according to an owner or usage of the PDCCH. For example, if the PDCCH is for a specific UE, the CRS is masked with a UE identifier (e.g., cell-RNTI (C-RNTI)). If the PDCCH is for a paging message, the CRC is masked with a paging RNTI (P-RNTI). If the PDCCH is for system information (e.g., system information block (SIB)), the CRC is masked with a system information RNTI (SI-RNTI). If the PDCCH is for a random access response, the CRC is masked with a random access-RNTI (RA-RNTI).
When a PDCCH on one serving cell schedules a PDSCH or a PUSCH on another serving cell, it is referred to cross-carrier scheduling. Cross-carrier scheduling with a carrier indicator field (CIF) may allow a PDCCH on a serving cell to schedule resources on another serving cell. When a PDSCH on a serving cell schedules a PDSCH or a PUSCH on the serving cell, it is referred to as self-carrier scheduling. When the cross-carrier scheduling is used in a cell, the BS may provide information about a cell scheduling the cell to the UE. For example, the BS may inform the UE whether a serving cell is scheduled by a PDCCH on another (scheduling) cell or scheduled by the serving cell. If the serving cell is scheduled by the other (scheduling) cell, the BS may inform the UE which cell signals DL assignments and UL grants for the serving cell. In the present disclosure, a cell carrying a PDCCH is referred to as a scheduling cell, and a cell where transmission of a PUSCH or a PDSCH is scheduled by DCI included in the PDCCH, that is, a cell carrying the PUSCH or PDSCH scheduled by the PDCCH is referred to as a scheduled cell.
A PDSCH is a physical layer UL channel for UL data transport. The PDSCH carries DL data (e.g., DL-SCH transport block) and is subjected to modulation such as quadrature phase shift keying (QPSK), 16 quadrature amplitude modulation (QAM), 64 QAM, 256 QAM, etc. A codeword is generated by encoding a transport block (TB). The PDSCH may carry a maximum of two codewords. Scrambling and modulation mapping per codeword may be performed and modulation symbols generated from each codeword may be mapped to one or more layers. Each layer is mapped to a radio resource together with a DMRS and generated as an OFDM symbol signal. Then, the OFDM symbol signal is transmitted through a corresponding antenna port.
A PUCCH is a physical layer UL channel for uplink control information (UCI) transmission. The PUCCH carries UCI. UCI types transmitted on the PUCCH include hybrid automatic repeat request acknowledgement (HARQ-ACK) information, a scheduling request (SR), and channel state information (CSI). UCI bits include HARQ-ACK information bits if present, SR information bits if present, link recovery request (LRR) information bits if present, and CSI bits if present. In the present disclosure, HARQ-ACK information bits correspond to a HARQ-ACK codebook. In particular, a bit sequence in which HARQ-ACK information bits are arranged according to a predetermined rule is called a HARQ-ACK codebook.
In the present disclosure, for convenience, PUCCH resources configured/indicated for/to the UE by the BS for HARQ-ACK, SR, and CSI transmission are referred to as a HARQ-ACK PUCCH resource, an SR PUCCH resource, and a CSI PUCCH resource, respectively.
A scheduling request (SR) is used for the UE to request UL-SCH resources for a (new) transmission. A MAC entity in the MAC layer above the PHY layer may be configured with zero, one, or more SR configurations. An SR configuration includes a set of PUCCH resources for an SR across different BWPs. To accommodate different types of data transfer services, a plurality of types of logical channels are defined, each supporting a specific type of information. The MAC entity supports mapping between logical channels and transport channels (e.g., UL-SCH and DL SCH). For a logical channel, at most one PUCCH resource for an SR is configured per BWP. For a logical channel, for example, an SR configuration applicable to the logical channel may be indicated to the UE by the ID of the SR configuration. Each SR configuration corresponds to one or more logical channels. Each logical channel may be mapped to zero or more SR configurations, which are configured by RRC signaling from the network. If an SR is triggered, the MAC entity has an SR TO on a valid PUCCH resource configured for the SR, an SR prohibit timer is not running at the time of the SR TO, and the PUCCH resource for the SR TO does not overlap with a measurement gap or with a UL-SCH resource (e.g., a PUSCH resource), the MAC entity instructs the PHY layer below the MAC layer to signal the SR on one valid PUCCH resource for the SR. If, for a logical channel belonging to a logical channel group including the one or more logical channels, UL data is available to the MAC entity and if there is no UL resource available for a new transmission, the SR may be triggered.
The UE is configured, by a higher-layer (e.g., RRC) parameter SchedulingRequestResourceConfig provided by the network, with a set of configurations for an SR in a PUCCH transmission using either PUCCH format 0 or PUCCH format 1. The higher-layer (e.g., RRC) parameter SchedulingRequestResourceConfig may include a parameter SchedulingRequestResourceId identifying an SR resource on a PUCCH, a parameter SchedulingRequestId indicating the ID of an SR configuration using the SR resource, and a parameter periodicityAndOffse indicating an SR periodicity and an SR offset. The parameter SchedulingRequestResourceConfig may include the ID of a PUCCH resource on which the UE will transmit the SR. The UE is configured with the PUCCH resource by the higher-layer parameter SchedulingRequestResourceId providing a PUCCH format 0 resource or a PUCCH format 1 resource. The UE is also configured with a periodicity SRPERIODICITY in symbols or slots and an offset SROFFSET in slots by the higher-layer parameter periodicityAndOffset of the network for a PUCCH transmission conveying the SR. If SRPERIODICITY is larger than one slot, the UE may determine the SR TO in the PUCCH to be in a slot with number Nus,f in a frame with number nf if (nf*Nframe,uslot+nus,f−SROFFSET)modSRPERIODICITY=0. If SRPERIODICITY is one slot, the UE expects that SROFFSET=0 and every slot is an SR TO in the PUCCH. If SRPERIODICITY is smaller than one slot, the UE determines the SR TO in the PUCCH to start in a symbol with index l if (l−l0modSRPERIODICITY)modSRPERIODICITY=0 where l0 is the index of the starting symbol of the corresponding PUCCH format. According to some scenarios (e.g., 3GPP TS 38.213 Rel-15), the UE transmits a PUCCH in a PUCCH resource for a corresponding SR configuration only when the UE transmits a positive SR. Further, according to some scenarios (e.g., 3GPP TS 38.213 Rel-150), the UE is configured to transmit K PUCCHs for respective K SRs in a slot, as determined by a set of SchedulingRequestResourceId, with SR TOs that would overlap with a PUCCH transmission with HARQ-ACK information from the UE in the slot or with a PUCCH transmission with CSI report(s) from the UE in the slot.
For example, if the UE would transmit a PUCCH with OACK HARQ-ACK information bits in a resource using PUCCH format 2 or PUCCH format 3 or PUCCH format 4 in a slot, ceil {log2(K+1)} bits representing a negative or positive SR are appended to the HARQ-ACK information bits in ascending order of the values of Scheduling RequestResourceId, and the UE transmits the combined UCI bits on a PUCCH using a resource with PUCCH format 2 or PUCCH format 3 or PUCCH format 4 for transmission of HARQ-ACK information bits. An all-zero value for the ceil{log2(K+1)} bits represents a negative SR value across all K SRs.
In another example, if the UE would transmit periodic/semi-persistent CSI in a resource using PUCCH format 2 or PUCCH format 3 or PUCCH format 4 in a slot, ceil{log2(K+1)} bits representing the corresponding negative or positive SR are prepended to the periodic/semi-persistent CSI bits in ascending order of the values of SchedulingRequestResourceId, and the UE transmits a PUCCH with the combined UCI bits in a resource with PUCCH format 2 or PUCCH format 3 or PUCCH format 4 for CSI reporting.
PUCCH formats may be defined as follows according to UCI payload sizes and/or transmission lengths (e.g., the number of symbols included in PUCCH resources). In regard to the PUCCH formats, reference may also be made to Table 4.
(0) PUCCH format 0 (PFO or FO)
(1) PUCCH format 1 (PF1 or F1)
Transmission structure: The DMRS and UCI are configured/mapped in TDM in/to different OFDM symbols. In other words, the DMRS is transmitted in symbols in which modulation symbols are not transmitted and the UCI is represented as the product between a specific sequence (e.g., orthogonal cover code (OCC)) and a modulation (e.g., QPSK) symbol. Code division multiplexing (CDM) is supported between a plurality of PUCCH resources (conforming to PUCCH format 1) (within the same RB) by applying cyclic shifts (CSs)/OCCs to both the UCI and the DMRS. PUCCH format 1 carries the UCI of up to 2 bits and the modulation symbols are spread by the OCC (differently configured depending on whether frequency hopping is performed) in the time domain.
(2) PUCCH format 2 (PF2 or F2)
(3) PUCCH format 3 (PF3 or F3)
Configuration for PUCCH format 3 includes the following parameters for a corresponding PUCCH resource: the number of PRBs, the number of symbols for PUCCH transmission, and/or the first symbol for PUCCH transmission.
(4) PUCCH format 4 (PF4 or F4)
The table below shows the PUCCH formats. The PUCCH formats may be divided into short PUCCH formats (formats 0 and 2) and long PUCCH formats (formats 1, 3, and 4) according to PUCCH transmission length.
A PUCCH resource may be determined according to a UCI type (e.g., A/N, SR, or CSI). A PUCCH resource used for UCI transmission may be determined based on a UCI (payload) size. For example, the BS may configure a plurality of PUCCH resource sets for the UE, and the UE may select a specific PUCCH resource set corresponding to a specific range according to the range of the UCI (payload) size (e.g., numbers of UCI bits). For example, the UE may select one of the following PUCCH resource sets according to the number of UCI bits, NUCI.
. . .
Here, K represents the number of PUCCH resource sets (K>1) and Ni represents a maximum number of UCI bits supported by PUCCH resource set #i. For example, PUCCH resource set #1 may include resources of PUCCH formats 0 to 1, and the other PUCCH resource sets may include resources of PUCCH formats 2 to 4 (see Table 4).
Configuration for each PUCCH resource includes a PUCCH resource index, a start PRB index, and configuration for one of PUCCH format 0 to PUCCH format 4. The UE is configured with a code rate for multiplexing HARQ-ACK, SR, and CSI report(s) within PUCCH transmission using PUCCH format 2, PUCCH format 3, or PUCCH format 4, by the BS through a higher layer parameter maxCodeRate. The higher layer parameter maxCodeRate is used to determine how to feed back the UCI on PUCCH resources for PUCCH format 2, 3, or 4.
If the UCI type is SR and CSI, a PUCCH resource to be used for UCI transmission in a PUCCH resource set may be configured for the UE through higher layer signaling (e.g., RRC signaling). If the UCI type is HARQ-ACK for a semi-persistent scheduling (SPS) PDSCH, the PUCCH resource to be used for UCI transmission in the PUCCH resource set may be configured for the UE through higher layer signaling (e.g., RRC signaling). On the other hand, if the UCI type is HARQ-ACK for a PDSCH scheduled by DCI, the PUCCH resource to be used for UCI transmission in the PUCCH resource set may be scheduled by the DCI.
In the case of DCI-based PUCCH resource scheduling, the BS may transmit the DCI to the UE on a PDCCH and indicate a PUCCH resource to be used for UCI transmission in a specific PUCCH resource set by an ACK/NACK resource indicator (ARI) in the DCI. The ARI may be used to indicate a PUCCH resource for ACK/NACK transmission and also be referred to as a PUCCH resource indicator (PRI). Here, the DCI may be used for PDSCH scheduling and the UCI may include HARQ-ACK for a PDSCH. The BS may configure a PUCCH resource set including a larger number of PUCCH resources than states representable by the ARI by (UE-specific) higher layer (e.g., RRC) signaling for the UE. The ARI may indicate a PUCCH resource subset of the PUCCH resource set and which PUCCH resource in the indicated PUCCH resource subset is to be used may be determined according to an implicit rule based on transmission resource information about the PDCCH (e.g., the starting CCE index of the PDCCH).
For UL-SCH data transmission, the UE should include UL resources available for the UE and, for DL-SCH data reception, the UE should include DL resources available for the UE. The UL resources and the DL resources are assigned to the UE by the BS through resource allocation. Resource allocation may include time domain resource allocation (TDRA) and frequency domain resource allocation (FDRA). In the present disclosure, UL resource allocation is also referred to as a UL grant and DL resource allocation is referred to as DL assignment. The UL grant is dynamically received by the UE on the PDCCH or in RAR or semi-persistently configured for the UE by the BS through RRC signaling. DL assignment is dynamically received by the UE on the PDCCH or semi-persistently configured for the UE by the BS through RRC signaling.
On UL, the BS may dynamically allocate UL resources to the UE through PDCCH(s) addressed to a cell radio network temporary Identifier (C-RNTI). The UE monitors the PDCCH(s) in order to discover possible UL grant(s) for UL transmission. The BS may allocate the UL resources using a configured grant to the UE. Two types of configured grants, Type 1 and Type 2, may be used. In Type 1, the BS directly provides the configured UL grant (including periodicity) through RRC signaling. In Type 2, the BS may configure a periodicity of an RRC-configured UL grant through RRC signaling and signal, activate, or deactivate the configured UL grant through the PDCCH addressed to a configured scheduling RNTI (CS-RNTI). For example, in Type 2, the PDCCH addressed to the CS-RNTI indicates that the corresponding UL grant may be implicitly reused according to the configured periodicity through RRC signaling until deactivation.
On DL, the BS may dynamically allocate DL resources to the UE through PDCCH(s) addressed to the C-RNTI. The UE monitors the PDCCH(s) in order to discover possible DL grant(s). The BS may allocate the DL resources to the UE using SPS. The BS may configure a periodicity of configured DL assignment through RRC signaling and signal, activate, or deactivate the configured DL assignment through the PDCCH addressed to the CS-RNTI. For example, the PDCCH addressed to the CS-RNTI indicates that the corresponding DL assignment may be implicitly reused according to the configured periodicity through RRC signaling until deactivation.
Hereinafter, resource allocation by the PDCCH and resource allocation by RRC will be described in more detail.
The PDCCH may be used to schedule DL transmission on the PDSCH and UL transmission on the PUSCH. DCI on the PDCCH for scheduling DL transmission may include DL resource assignment that at least includes a modulation and coding format (e.g., modulation and coding scheme (MCS)) index IMCS), resource allocation, and HARQ information, associated with a DL-SCH. DCI on the PDCCH for scheduling UL transmission may include a UL scheduling grant that at least includes a modulation and coding format, resource allocation, and HARQ information, associated with a UL-SCH. HARQ information on a DL-SCH or UL-SCH may include a new information indicator (NDI), transport block size (TBS), redundancy version (RV), and HARQ process ID (i.e., HARQ process number). The size and usage of the DCI carried by one PDCCH differs according to a DCI format. For example, DCI format 0_0, DCI format 0_1, or DCI format 0_2 may be used to schedule the PUSCH, and DCI format 1_0, DCI format 1_1, or DCI format 1_2 may be used to schedule the PDSCH. Particularly, DCI format 0_2 and DCI format 1_2 may be used to schedule transmission having higher transmission reliability and lower latency requirements than transmission reliability and latency requirement guaranteed by DCI format 0_0, DCI format 0_1, DCI format 1_0, or DCI format 1_1. Some implementations of the present disclosure may be applied to UL data transmission based on DCL format 0_2. Some implementations of the present disclosure may be applied to DL data reception based on DCI format 1_2.
DCI carried by the PDCCH in order to schedule a PDSCH or a PUSCH includes a TDRA field. The TDRA field provides a value m for a row index m+1 to an allocation table for the PDSCH or the PUSCH. Predefined default PDSCH time domain allocation is applied as the allocation table for the PDSCH or a PDSCH TDRA table that the BS configures through RRC signaled pdsch-TimeDomainAllocationList is applied as the allocation table for the PDSCH. Predefined default PUSCH time domain allocation is applied as the allocation table for the PUSCH or a PUSCH TDRA table that the BS configures through RRC signaled pusch-TimeDomainAllocationList is applied as the allocation table for the PUSCH. The PDSCH TDRA table to be applied and/or the PUSCH TDRA table to be applied may be determined according a fixed/predefined rule (e.g., refer to 3GPP TS 38.214).
In PDSCH time domain resource configurations, each indexed row defines a DL assignment-to-PDSCH slot offset K0, a start and length indicator value SLIV (or directly, a start position (e.g., start symbol index S) and an allocation length (e.g., the number of symbols, L) of the PDSCH in a slot), and a PDSCH mapping type. In PUSCH time domain resource configurations, each indexed row defines a UL grant-to-PUSCH slot offset K2, a start position (e.g., start symbol index S) and an allocation length (e.g., the number of symbols, L) of the PUSCH in a slot, and a PUSCH mapping type. K0 for the PDSCH and K2 for the PUSCH indicate the difference between the slot with the PDCCH and the slot with the PDSCH or PUSCH corresponding to the PDCCH. SLIV denotes a joint indicator of the start symbol S relative to the start of the slot with the PDSCH or PUSCH and the number of consecutive symbols, L, counting from the symbol S. There are two PDSCH/PUSCH mapping types: one is mapping type A and the other is mapping type B. In the case of PDSCH/PUSCH mapping type A, a DMRS is mapped to a PDSCH/PUSCH resource with respect to the start of a slot. One or two of the symbols of the PDSCH/PUSCH resource may be used as DMRS symbol(s) according to other DMRS parameters. For example, in the case of PDSCH/PUSCH mapping type A, the DMRS is located in the third symbol (symbol #2) or the fourth symbol (symbol #3) in the slot according to RRC signaling. In the case of PDSCH/PUSCH mapping type B, a DMRS is mapped with respect to the first OFDM symbol of a PDSCH/PUSCH resource. One or two symbols from the first symbol of the PDSCH/PUSCH resource may be used as DMRS symbol(s) according to other DMRS parameters. For example, in the case of PDSCH/PUSCH mapping type B, the DMRS is located at the first symbol allocated for the PDSCH/PUSCH. In the present disclosure, the PDSCH/PUSCH mapping type may be referred to as a mapping type or a DMRS mapping type. For example, in the present disclosure, PUSCH mapping type A may be referred to as mapping type A or DMRS mapping type A, and PUSCH mapping type B may be referred to as mapping type B or DMRS mapping type B.
The scheduling DCI includes an FDRA field that provides assignment information about RBs used for the PDSCH or the PUSCH. For example, the FDRA field provides information about a cell for PDSCH or PUSCH transmission to the UE, information about a BWP for PDSCH or PUSCH transmission, and/or information about RBs for PDSCH or PUSCH transmission.
As mentioned above, there are two types of transmission without dynamic grant: configured grant Type 1 and configured grant Type 2. In configured grant Type 1, a UL grant is provided by RRC and stored as a configured UL grant. In configured grant Type 2, the UL grant is provided by the PDCCH and stored or cleared as the configured UL grant based on L1 signaling indicating configured UL grant activation or deactivation. Type 1 and Type 2 may be configured by RRC per serving cell and per BWP. Multiple configurations may be active simultaneously on different serving cells.
When configured grant Type 1 is configured, the UE may be provided with the following parameters through RRC signaling:
Upon configuration of configured grant Type 1 for a serving cell by RRC, the UE stores the UL grant provided by RRC as a configured UL grant for an indicated serving cell and initializes or re-initializes the configured UL grant to start in a symbol according to time DomainOffset and S (derived from SLIV) and to recur with periodicity. After the UL grant is configured for configured grant Type 1, the UE may consider that the UL grant recurs in association with each symbol satisfying: [(SFN*numberOfSlotsPerFrame (numberOfSymbolsPerSlot)+(slot number in the frame*numberOfSymbolsPerSlot)+symbol number in the slot]=(timeDomainOffset*numberOfSymbolsPerSlot+S+N*periodicity) modulo (1024*numberOfSlotsPerFrame*numberOfSymbolsPerSlot), for all N>=0, where numberOfSlotsPerFrame and numberOfSymbolsPerSlot indicate the number of consecutive slots per frame and the number of consecutive OFDM symbols per slot, respectively (refer to Table 1 and Table 2).
For configured grant Type 2, the UE may be provided with the following parameters by the BS through RRC signaling:
An actual UL grant is provided to the UE by the PDCCH (addressed to the CS-RNTI). After the UL grant is configured for configured grant Type 2, the UE may consider that the UL grant recurs in association with each symbol satisfying: [(SFN*numberOfSlotsPerFrame* numberOfSymbolsPerSlot)+(slot number in the frame*numberOfSymbolsPerSlot)+symbol number in the slot]=[(SFNstart time*numberOfSlotsPerFrame*numberOfSymbolsPerSlot+slotstart time*numberOfSymbolsPerSlot+symbolstart time)+N*periodicity] modulo (1024* numberOfSlotsPerFrame*numberOfSymbolsPerSlot), for all N>=0, where SFNstart time, slotstart time, and symbolstart time represent an SFN, a slot, and a symbol, respectively, of the first transmission opportunity of the PUSCH after the configured grant is (re-)initialized, and numberOfSlotsPerFrame and numberOfSymbolsPerSlot indicate the number of consecutive slots per frame and the number of consecutive OFDM symbols per slot, respectively (refer to Table 1 and Table 2).
In some scenarios, a parameter harq-ProcID-Offset and/or a parameter harq-ProcID-Offset2 used to derive HARQ process IDs for configured UL grants may be further provided by the BS to the UE. harq-ProcID-Offset is an offset of a HARQ process for a configured grant for operation with shared spectrum channel access, and harq-ProcID-Offset2 is an offset of a HARQ process for a configured grant. In the present disclosure, cg-RetransmissionTimer is a duration after (re)transmission based on a configured grant in which the UE should not autonomously perform retransmission based on the HARQ process of the (re)transmission. cg-RetransmissionTimer may be provided to the UE by the BS when retransmission on a configured UL grant is configured. For configured grants configured with neither harq-ProcID-Offset nor cg-RetransmissionTimer, the HARQ process ID associated with the first symbol of UL transmission may be derived from the following equation: HARQ Process ID=[floor(CURRENT_symbol/periodicity)] modulo nrofHARQ-Processes. For configured UL grants with harq-ProcID-Offset2, the HARQ process ID associated with the first symbol of UL transmission may be derived from the following equation: HARQ Process ID=[floor(CURRENT_symbol/periodicity)] modulo nrofHARQ-Processes+harq-ProcID-Offset2, where CURRENT_symbol=(SFN*numberOfSlotsPerFrame*numberOfSymbolsPerSlot+slot number in the frame*numberOfSymbolsPerSlot+symbol number in the slot), and numberOfSlotsPerFrame and numberOfSymbolsPerSlot denote the number of consecutive slots per frame and the number of consecutive OFDM symbols per slot, respectively. For configured UL grants with cg-RetransmissionTimer, the UE may select a HARQ process ID from among HARQ process IDs available for the configured grant configuration.
On DL, the UE may be configured with semi-persistent scheduling (SPS) per serving cell and per BWP by RRC signaling from the BS. For DL SPS, DL assignment is provided to the UE by the PDCCH and stored or cleared based on L1 signaling indicating SPS activation or deactivation. When SPS is configured, the UE may be provided with the following parameters by the BS through RRC signaling (e.g., SPS configuration) used to configure a semi-persistent transmission:
Multiple DL SPS configurations may be configured within the BWP of a serving cell. After DL assignment is configured for SPS, the UE may consider sequentially that N-th DL assignment occurs in a slot satisfying: (numberOfSlotsPerFrame*SFN+slot number in the frame)=[(numberOfSlotsPerFrame*SFNstart time +slotstart time)+N*periodicity* numberOfSlotsPerFrame/10] modulo (1024*numberOfSlotsPerFrame), where SFNstart timeand slotstart time represent an SFN and a slot, respectively, of first transmission of the PDSCH after configured DL assignment is (re-)initialized, and numberOfSlotsPerFrame and numberOfSymbolsPerSlot indicate the number of consecutive slots per frame and the number of consecutive OFDM symbols per slot, respectively (refer to Table 1 and Table 2).
In some scenarios, a parameter harq-ProcID-Offset used to derive HARQ process IDs for configured DL assignments may be further provided by the BS to the UE. harq-ProcID-Offset is an offset of a HARQ process for SPS. For configured DL assignments without harq-ProcID-Offset, a HARQ process ID associated with a slot in which DL transmission starts may be determined from the following equation: HARQ Process ID=[floor(CURRENT_slot*10/(numberOfSlotsPerFrame *periodicity))] modulo nrofHARQ-Processes, where CURRENT_slot=[(SFN*numberOfSlotsPerFrame)+slot number in the frame], and numberOfSlotsPerFrame denotes the number of consecutive slots per frame. For configured DL assignments with harq-ProcID-Offset, a HARQ process ID associated with a slot in which DL transmission starts may be determined from the following equation: HARQ Process ID=[floor (CURRENT_slot/periodicity)] modulo nrofHARQ-Processes+harq-ProcID-Offset, where CURRENT_slot=[(SFN*numberOfSlotsPerFrame)+slot number in the frame], and numberOfSlotsPerFrame denotes the number of consecutive slots per frame.
If the CRC of a corresponding DCI format is scrambled with the CS-RNTI provided by the RRC parameter cs-RNTI, and a new data indicator field for an enabled transport block is set to 0, the UE validates, for scheduling activation or scheduling release, a DL SPS assignment PDCCH or a configured UL grant Type 2 PDCCH. Validation of the DCI format is achieved if all fields for the DCI format are set according to Table 5 and Table 6. Table 5 shows an example of special fields for DL SPS and UL grant Type 2 scheduling activation PDCCH validation, and Table 6 shows an example of special fields for DL SPS and UL grant Type 2 scheduling release PDCCH validation.
Actual DL assignment and UL grant for DL SPS or UL grant Type 2, and a corresponding MCS are provided by resource assignment fields (e.g., a TDRA field providing a TDRA value m, an FDRA field providing frequency resource block assignment, and/or an MCS field) in the DCI format carried by a corresponding DL SPS or UL grant Type 2 scheduling activation PDCCH. If validation is achieved, the UE considers information in the DCI format as valid activation or valid release of DL SPS or configured UL grant Type 2.
In the present disclosure, a PDSCH based on DL SPS may be referred to as an SPS PDSCH, and a PUSCH based on a UL configured grant (CG) may be referred to as a CG PUSCH. A PDSCH dynamically scheduled by DCI carried on a PDCCH may be referred to as a dynamic grant (DG) PDSCH, and a PUSCH dynamically scheduled by DCI carried by on a PDCCH may be referred to as a DG PUSCH.
Referring to
The DCI (e.g., DCI format 1_0 or DCI format 1_1) carried by the PDCCH for scheduling the PDSCH may include the following information.
If the PDSCH is configured to transmit a maximum of one TB, a HARQ-ACK response may consist of one bit. If the PDSCH is configured to transmit a maximum of 2 TBs, the HARQ-ACK response may consist of 2 bits when spatial bundling is not configured and one bit when spatial bundling is configured. When a HARQ-ACK transmission timing for a plurality of PDSCHs is designated as slot n+K1, UCI transmitted in slot n+K1 includes a HARQ-ACK response for the plural PDSCHs.
In the present disclosure, a HARQ-ACK payload consisting of HARQ-ACK bit(s) for one or plural PDSCHs may be referred to as a HARQ-ACK codebook. The HARQ-ACK codebook may be categorized as i) a semi-static HARQ-ACK codebook, ii) a dynamic HARQ-ACK codebook and iii) HARQ process based HARQ-ACK codebook, according to a HARQ-ACK payload determination scheme.
In the case of the semi-static HARQ-ACK codebook, parameters related to a HARQ-ACK payload size that the UE is to report are semi-statically determined by a (UE-specific) higher layer (e.g., RRC) signal. The HARQ-ACK payload size of the semi-static HARQ-ACK codebook, e.g., the (maximum) HARQ-ACK payload (size) transmitted through one PUCCH in one slot, may be determined based on the number of HARQ-ACK bits corresponding to a combination (hereinafter, bundling window) of all DL carriers (i.e., DL serving cells) configured for the UE and all DL scheduling slots (or PDSCH transmission slots or PDCCH monitoring slots) for which the HARQ-ACK transmission timing may be indicated. That is, in a semi-static HARQ-ACK codebook scheme, the size of the HARQ-ACK codebook is fixed (to a maximum value) regardless of the number of actually scheduled DL data. For example, DL grant DCI (PDCCH) includes PDSCH-to-HARQ-ACK timing information, and the PDSCH-to-HARQ-ACK timing information may have one (e.g., k) of a plurality of values. For example, when the PDSCH is received in slot #m and the PDSCH-to-HARQ-ACK timing information in the DL grant DCI (PDCCH) for scheduling the PDSCH indicates k, the HARQ-ACK information for the PDSCH may be transmitted in slot #(m+k). As an example, k∈{1, 2, 3, 4, 5, 6, 7, 8}. When the HARQ-ACK information is transmitted in slot #n, the HARQ-ACK information may include possible maximum HARQ-ACK based on the bundling window. That is, HARQ-ACK information of slot #n may include HARQ-ACK corresponding to slot #(n-k). For example, when k∈{1, 2, 3, 4, 5, 6, 7, 8}, the HARQ-ACK information of slot #n may include HARQ-ACK corresponding to slot #(n-8) to slot #(n-1) regardless of actual DL data reception (i.e., HARQ-ACK of a maximum number). Here, the HARQ-ACK information may be replaced with a HARQ-ACK codebook or a HARQ-ACK payload. A slot may be understood/replaced as/with a candidate occasion for DL data reception. As described in the example, the bundling window may be determined based on the PDSCH-to-HARQ-ACK timing based on a HARQ-ACK slot, and a PDSCH-to-HARQ-ACK timing set may have predefined values (e.g., {1, 2, 3, 4, 5, 6, 7, 8}) or may be configured by higher layer (RRC) signaling. The semi-static HARQ-ACK codebook is referred to as a Type-1 HARQ-ACK codebook. For the Type-1 HARQ-ACK codebook, the number of bits to be transmitted in a HARQ-ACK report is fixed and may be potentially large. If many cells are configured but only few cells are scheduled, the Type-1 HARQ-ACK codebook may be inefficient.
In the case of the dynamic HARQ-ACK codebook, the HARQ-ACK payload size that the UE is to report may be dynamically changed by the DCI etc. The dynamic HARQ-ACK codebook is referred to as a Type-2 HARQ-ACK codebook. The Type-2 HARQ-ACK codebook may be considered as optimized HARQ-ACK feedback because the UE sends feedback only for scheduled serving cells. However, in poor channel conditions, the UE may erroneously determine the number of scheduled serving cells. To solve this problem, a downlink assignment index (DAI) may be included as a part of DCI. For example, in the dynamic HARQ-ACK codebook scheme, DL scheduling DCI may include a counter-DAI (i.e., c-DAI) and/or a total-DAI (i.e., t-DAI). Here, the DAI indicates a downlink assignment index and is used for the BS to inform the UE of transmitted or scheduled PDSCH(s) for which HARQ-ACK(s) are to be included in one HARQ-ACK transmission. Particularly, the c-DAI is an index indicating order between PDCCHs carrying DL scheduling DCI (hereinafter, DL scheduling PDCCHs), and t-DAI is an index indicating the total number of DL scheduling PDCCHs up to a current slot in which a PDCCH with the t-DAI is present.
In the case of a HARQ-ACK codebook based on HARQ processes, the HARQ-ACK payload is determined based on all HARQ processes of all configured (or activated) serving cells in a PUCCH group. For example, the size of the HARQ-ACK payload to be reported by the UE using the HARQ-ACK codebook based on HARQ processes may be determined based on the number of all configured or activated serving cells in the PUCCH group configured for the UE and the number of HARQ processes for the serving cells. The HARQ-ACK codebook based on HARQ processes is also referred to as a Type-3 HARQ-ACK codebook. The type-3 HARQ-ACK codebook may be applied to one-shot feedback.
Extended reality (XR) is an ultra-immersive technology and service that provides an environment in which the users are capable of communicating and living without restrictions on time and space in a virtual space similar to reality by utilizing virtual reality (VR), augmented reality (AR), mixed reality (MR), holography, etc. XR is one of major services to be introduced in an NR wireless communication system. XR is typically characterized by specific traffic with one or more DL video streams which are closely synchronized with frequent UL pose/control updates. In addition, XR has a high data rate and a stringent packet delay budget (PDB).
A video stream is the most important flow for XR use cases. A video is divided into separate frames before transmission. A data packet representing a video frame may be transmitted wirelessly. An average inter-arrival time of packets is the reciprocal of a frame rate in frames per second. For video streams, if there are a lot of changes in the video on a screen, the communication traffic is high, whereas if there are few change in the video, the traffic is low.
In XR, videos need to be displayed accurately on the screen in accordance with the flow of time. Therefore, once the point in time at which the provision of XR data is required has passed, the previous data becomes useless, and it is better to provide new data.
A successful implementation of XR requires support from a wireless system. In a 3GPP-based wireless communication system, for example, in an NR wireless communication system, utilizing preconfigured resources such as SPS/CG is being considered to support XR. For example, the BS may provide an SPS/CG configuration to the UE in consideration of an average inter-arrival time of packets. However, the actual inter-arrival time of packets is random due to jitter. Jitter refers to a deviation of time that undesirably occurs in a signal having a periodicity. In XR, since the amount of information per frame is different, a time required to process frames before transmitting the frames is different, resulting in jitter. Therefore, even if SPS/CG resources that occur periodically are configured for the UE, the UE may fail to perform PDSCH reception/PUSCH transmission in a PDSCH occasion/PUSCH occasion due to jitter.
The present disclosure describes: method(s) of activating and/or deactivating a plurality of semi-static configurations (e.g., SPS, configured grant, and/or scheduling request) for a single service when a UE receives a plurality of services and the plurality of semi-static configurations are used for the single service; and method(s) of activating and/or deactivating a plurality of associated semi-static configurations when the use of the corresponding service starts or ends.
In NR, one or more SPS PDSCHs or CG PUSCHs may be configured for the UE for periodic transmission and reception or a low delay time and PDCCH overhead. A corresponding configured/indicated resource may be repeated in the time domain with a periodicity according to each SPS/CG configuration. For example, first configured/indicated resource allocation may be repeated at a configured periodicity by the SPS/CG configuration, and the UE may perform DL reception/UL transmission on a corresponding resource without a separate PDCCH reception process. Meanwhile, there are various types of data that may be generated in XR. Among the data, it is considered that sensor and location information of the UE and video data, generally reported at a specific periodicity, are transmitted and received on SPS/CG resources. In such data, a traffic arrival time is not constant and jitter may occur for reasons such as a video encoding time, a sensor measurement time, a higher layer operation, or a routing change of a network.
For XR services, dynamic scheduling may also be considered. When latency-sensitive XR services are used, it is necessary to consider a method for ensuring that such transmissions are not canceled by other transmissions. In addition, the UE needs to receive appropriate DL assignments and/or UL grants for the service. In NR, a priority at the PHY layer has been introduced for a plurality of services. Thus, the UE may perform UL transmission or DL reception using only one of overlapping radio resources. Alternatively, the UE may divide overlapping UL transmissions into a plurality of groups and perform UL multiplexing. In this process, lower-priority transmissions may be canceled, and thus a method of preventing the cancellation of XR transmissions need to be considered.
If the BS allocates resources to a location sufficiently far away in time from an expected traffic occurrence time point in consideration of jitter at a data occurrence time point, availability of resources may be guaranteed, but a delay time may occur. Conversely, if an SPS/CG resource with a fixed periodicity is allocated at an expected data occurrence time point, a greater delay time may occur due to a waiting time to the next available resource during occurrence of jitter.
On the other hand, since some data is generated based on events, it is impossible to accurately determine an actual data occurrence time point. However, it is considered to use the SPS/CG resource even for such data in order to reduce a delay time caused by scheduling. In this case, skipping method(s) in which a network allocates a sufficiently large number of resources at a short periodicity in preparation for occurrence of data, and the UE or BS selectively uses some of these resources and does not actually use other resource(s) may be considered. However, in order to use the method of skipping transmission and reception, the UE and BS needs to carefully consider a response signal for determining whether to perform reception and/or transmission between the UE and the BS. If the UE needs to transmit the response signal even for transmission that the UE has not received, the BS should always prepare for resources on which the UE is to transmit the response signal. Considering that the skipping method is based on configuring a sufficiently large number of resources within radio resources, configuring resources so that the UE may transmit the response signal even for transmission that the UE has not received may act as significant UL burden. Considering that these resources may be multiplexed between UEs, the burden of UL resources should be considered more important.
The size of the data, latency, and reliability required by each service may differ. For more accurate and rapid UL scheduling, the UE may transmit an SR to the BS, and upon receiving the SR, the BS may quickly transmit a UL grant to the UE. The SR may be associated with logical channels of the higher layer. Since the associated logical channels may be linked with services and traffic that have the same attributes or requirements, the UE may receive a plurality of SR configurations for services with different requirements.
When XR services or similar third-party services are used, the aforementioned aspects need to be considered. For instance, a plurality of semi-static configurations, such as SPS, CG, and/or SR configurations, may be required for a single service. Therefore, when such a service is in use, UE operations required when a plurality of semi-static configurations are used for a single service, such as a method of activating the associated semi-static configurations, need to be considered. The present disclosure describes method(s) for activating/deactivating semi-static configurations that may be associated with XR services, as well as method(s) of utilizing the activated semi-static configurations in accordance with the characteristics of the XR services.
Hereinbelow, while implementations of the present disclosure are described based on DL SPS and UL CG radio resources, which are semi-statically configured, the implementations of the present disclosure are not limited thereto and may be extensively applied to radio resources allocated through dynamic scheduling received by the UE. As an example, the implementation(s) of the present disclosure in which the UE determines one HARQ-ACK timing for a plurality of DL radio resources allocated thereto may be applied regardless of an SPS PDSCH and a PDSCH which is indicated by dynamic scheduling. Additionally, when a plurality of radio resources is not configured semi-statically and is configured through dynamic indication, for example, even when a plurality of radio resources is simultaneously configured through DCI, the implementations of the present disclosure may be applied. Therefore, the implementations of the present disclosure may be applied to all types of transmission/reception methods expected by the BS and the UE even if there is no separate explanation. Hereinafter, for convenience of description, the implementations of the present disclosure are described using SPS as a general term that collectively refers to semi-statically configured radio resources (e.g., DL/UL SPS and CG).
In some implementations of the present disclosure, a transmission occasion (TO) may refer to a radio resource configured for SPS/CG (e.g., an SPS PDSCH or a CG PUSCH). An entity performing transmission in a TO (e.g., a BS on DL or a UE on UL) may attempt to perform transmission in the TO, and a receiver (e.g., a UE on DL or a BS on UL) may attempt to perform reception while expecting that there will be transmission in each TO.
In the present disclosure, an SR transmission occasion (TO) may refer to radio resources allocated for SR purposes (e.g., SR PUCCH). An entity (i.e., UE) that performs transmission on an SR TO may attempt to transmit an SR on the SR TO, while a receiver (i.e., BS) may expect PUCCH transmission including the SR from the UE at each SR TO and attempt to receive an SR PUCCH.
Hereinbelow, while the implementations of the present disclosure will be described based on the NR system, the implementations of the present disclosure are not limited to the transmission/reception of NR. Additionally, while, in the present disclosure, the implementations of the present disclosure are described using characteristics and structures of the XR service as an example, the implementations of the present disclosure are not limited to support of the XR service. The implementations of the present disclosure may be applied to all wireless communication transmission/reception structures and services even without separate description.
The present disclosure describes implementations for activating/deactivating semi-static configurations. For example, the implementations of the present disclosure may include a method for the BS to allocate PDSCH/PUSCH radio resource(s) to the UE and a method for the UE to perform DL reception or UL transmission on the allocated radio resource(s). Some implementations of the present disclosure may include a method of transmitting a HARQ-ACK PUCCH response to a PDSCH reception result by the UE and a method of receiving retransmission DCI of the BS through a PDCCH after transmitting a PUSCH. In some implementations of the present disclosure, the UE may transmit signals and channels for announcing capabilities thereof and/or service requirements, and the BS may receive the signals and channels.
Some implementations of the present disclosure may be selectively applied in part. Some implementations of the present disclosure may be performed independently without combination with other implementations, or one or more implementations may be combined and performed in an associated form. Some terms, symbols, sequences, etc. used in the present disclosure may be replaced with other terms, symbols, sequences, etc. as long as the principle of implementations of the present disclosure is maintained.
The UE may receive a plurality of semi-static configurations (e.g., SPS, CG, and/or SR) from a BS through RRC signaling (S801). The semi-static configurations configured for the UE may be automatically activated or may initially be deactivated. The plurality of configured semi-static configurations may be activated/deactivated according to some implementations of the present disclosure (S803). For example, in some implementations, one or more semi-static configurations may be activated/deactivated through L1 signaling (e.g., DCI) and/or higher layer signaling from the BS. In some implementations, when transmission or reception is performed at the TO or SR TO of a specific semi-static configuration, another semi-static configuration may be activated/deactivated for a certain period of time or continuously. In some implementations, a group of configurations may be activated/deactivated based on a separately semi-statically configured or dynamically indicated activation/deactivation pattern. The UE may receive/transmit a PDSCH/PUSCH or transmit an SR PUCCH at the TO or SR TO of activated SPS/CG (S805). The UE is incapable of receiving/transmitting the PDSCH/PUSCH or transmitting the SR PUCCH at the TO or SR TO of deactivated SPS/CG. In some implementations of the present disclosure, the UE may assume that a deactivated semi-static configuration is not configured for the UE.
The BS may configure a plurality of semi-static configurations (e.g., SPS, CG, and/or SR) for the UE through RRC signaling (S901). The semi-static configurations configured for the UE may be automatically activated or may initially be deactivated. The plurality of configured semi-static configurations may be activated/deactivated according to some implementations of the present disclosure (S903). For example, in some implementations, one or more semi-static configurations may be activated/deactivated through L1 signaling (e.g., DCI) and/or higher layer signaling from the BS. In some implementations, when transmission or reception is performed at the TO or SR TO of a specific semi-static configuration, another semi-static configuration may be activated/deactivated for a certain period of time or continuously. In some implementations, a group of configurations may be activated/deactivated based on a separately semi-statically configured or dynamically indicated activation/deactivation pattern. The BS may transmit/receive a PDSCH/PUSCH or receive an SR PUCCH at the TO or SR TO of activated SPS/CG (S905). The BS is incapable of transmitting/receiving the PDSCH/PUSCH or receiving the SR PUCCH at the TO or SR TO of deactivated SPS/CG. In some implementations of the present disclosure, the BS may assume that a deactivated semi-static configuration is not configured for the UE.
The activation/deactivation according to some implementations of the present disclosure may be performed independently of conventional SPS/CG activation/deactivation (e.g., see Table 5 and Table 6). For example, unlike the conventional SPS/CG activation/deactivation that is used to newly allocate radio resources and release the allocated radio resources, in the activation/deactivation of a semi-static configuration according to some implementations of the present disclosure, resource allocation information for determining the TO or SR TO of each configuration may remain unchanged, but only the transmission and reception at the TO and/or SR TO of the corresponding configuration may be restricted. For instance, among the TOs of SPS/CG configurations that are activated or deactivated through the conventional SPS/CG activation/deactivation, TOs where actual transmission/reception is capable of being performed may be determined according to some implementations of the present disclosure. While the conventional SPS/CG activation/release involves configuring or releasing SPS/CG resources, the activation/release according to some implementations of the present disclosure may refer to temporarily turning on or off the SPS, CG, or SR, which has been activated, through the conventional SPS, CG, or SR activation. While the conventional activation/release is semi-static, SPS/CG/SR resources may be dynamically activated or released according to some implementations of the present disclosure
Some implementations of the present disclosure to be described below may be applied independently or in combination with two or more other implementations.
Some implementations of the present disclosure may be specified to be applied only when the UE receives relevant configuration information from the BS (or core network). To provide the configuration information, higher layer signaling (e.g., SIB or RRC signaling) or a method of indicating the activation/deactivation of the information configured for the UE through separate signaling (e.g., DCI or MAC control element) may be used. Additionally, the UE may be specified to report information regarding a capability to support the method(s) according to some implementations of the present disclosure, and the BS (or core network) may be specified to receive the information.
The UE and BS may activate or deactivate one or more semi-static configurations (SPS, CG, and/or SR) based on a semi-statically configured or dynamically indicated activation/deactivation pattern. In some implementations, one or more semi-static configurations (SPS, CG, and/or SR) may refer to only one or more semi-static configurations of the same type (SPS, CG, or SR). In some implementations, one or more semi-static configurations (SPS, CG, and/or SR) may refer to a semi-static configuration set consisting of one or more semi-static configurations in total, where the semi-static configuration set includes zero or more semi-static configurations of different types (SPS, CG, or SR) for each type.
The semi-statically configured or dynamically indicated activation/deactivation pattern may indicate whether a semi-static configuration is activated or deactivated for each specific time unit. For example, the activation/deactivation pattern may be a bitmap or bit sequence representing the activation or deactivation status of a semi-static configuration as 0 or 1 for each specific time unit (e.g., one slot length within a PCell or active DL BWP) over a certain period of time P. When such an activation/deactivation pattern is semi-statically configured and used, P may represent the period of the pattern.
The activation/deactivation pattern according to some implementations of the present disclosure may be indicated or configured for each type of semi-static configuration. Alternatively, the activation/deactivation pattern may be configured for each group of semi-static configurations if the groups exist. Alternatively, an activation/deactivation pattern with a unique identifier (ID) may be predefined or configured by the BS. Such a activation/deactivation pattern or groups of activation/deactivation patterns may be indicated to the UE through L1 signaling, for example, via scheduling DCI or group-common DCI or configured for each semi-static configuration SPS/CG/SR. When the activation/deactivation pattern is semi-statically configured and used for the SPS/CG/SR, the pattern may be applied from the start of an SPS/CG/SR period. For a time duration where the activation/deactivation pattern does not explicitly indicate activation or deactivation, a specific value (e.g., activation or deactivation) may be assumed.
The UE may determine whether to apply the activation/deactivation pattern according to some implementations of the present disclosure under a specific condition. For example, whether to apply the activation/deactivation pattern may be determined based on at least one of the following conditions.
When the activation/deactivation pattern is used or not used for SPS/CG/SR based on the above conditions, the application and release of the activation/deactivation pattern may be determined based on the start point of an SPS/CG/SR period. For a time duration where the activation/deactivation pattern does not explicitly indicate activation or deactivation, a specific value (e.g., activation or deactivation) may be assumed. Alternatively, if the activation/deactivation pattern is used or not used based on DCI reception/transmission, the application and release of the activation/deactivation pattern may be determined from the last symbol of a CORESET including a PDCCH carrying the DCI or from the start or end of a slot in which the PDCCH is received.
The UE may activate or deactivate one or more semi-static configurations (SPS, CG, and/or SR) based on a timer. The one or more semi-static configurations (SPS, CG, and/or SR) may refer to only one or more semi-static configurations of the same type (SPS, CG, or SR). Alternatively, the one or more semi-static configurations may refer to a semi-static configuration set consisting of one or more semi-static configurations in total, where the semi-static configuration set includes zero or more semi-static configurations of different types (SPS, CG, or SR) for each type.
For example, the UE may use the one or more semi-static configurations (SPS, CG, and/or SR) only while a specific timer is running. If the timer expires, the UE may stop using the corresponding configurations. On the other hand, the UE may not the corresponding configurations while the specific timer is running, and once the timer expires, the UE may use the corresponding configurations.
The length of the timer may be configured by L1 signaling and/or higher layer signaling from the BS, either for each semi-static configuration (SPS, CG, and/or SR) individually or commonly for one or more semi-static configurations (SPS, CG, and/or SR).
The timer may be started or restarted based on at least one of the following conditions.
In some implementations, if at least one of the applied conditions is triggered, the UE may not use associated SPS, CG, and/or SR configurations for a specific period of time (e.g., time window). Alternatively, if at least one of the applied conditions is triggered, the UE may use associated SPS, CG, and/or SR configurations only for a specific period of time (e.g., time window).
The UE may activate or deactivate one or more semi-static configurations (SPS, CG, and/or SR) based on an L1 indication (e.g., DCI) from the BS. The one or more semi-static configurations (SPS, CG, and/or SR) may refer to only one or more semi-static configurations of the same type (SPS, CG, or SR). Alternatively, the one or more semi-static configurations may refer to a semi-static configuration set consisting of one or more semi-static configurations in total, where the semi-static configuration set includes zero or more semi-static configurations of different types (SPS, CG, or SR) for each type.
The L1 indication may indicate a configuration ID of the one or more semi-static configurations (SPS, CG, and/or SR) or a group ID associated with the one or more semi-static configurations. Upon receiving L1 indication, the UE may activate or deactivate one or more semi-static configurations associated with the given ID.
Such activation/deactivation may be performed independently of the conventional SPS/CG activation/deactivation as described earlier.
The L1 indication may separately indicate the activation or deactivation. If the activation is indicated, the UE may activate the one or more semi-static configurations associated with the given ID in the L1 indication. If the deactivation is indicated, the UE may deactivate the one or more semi-static configurations associated with the given ID in the L1 indication.
The L1 indication may also implicitly indicate the activation or deactivation instead of explicitly specifying the activation or deactivation. For example, the UE may toggle the activation/deactivation state of the one or more semi-static configurations associated with the given ID in the L1 indication. For instance, upon receiving the L1 indication, if the one or more semi-static configurations associated with the given ID are in the activated state, the UE may deactivate the corresponding configurations. If the corresponding configurations are in the deactivated state, the UE may activate the corresponding configurations.
In applying Implementation 1, Implementation 2, and/or Implementation 3, the UE may determine the activation/deactivation of one or more semi-static configurations (SPS, CG, and/or SR) configured through L1 signaling and/or higher layer signaling from the BS. If the UE is configured with two or more semi-static configuration groups, the UE may perform switching between the two semi-static configuration groups based on an activation/deactivation indication and configuration according to some implementations of the present disclosure.
For example, if the UE is configured with semi-static configuration group A and semi-static configuration group B, the “activation” of group A according to Implementation 1, Implementation 2, and/or Implementation 3 may mean activating group A and deactivating group B. On the other hand, the “deactivation” of group A may mean deactivating group A and activating group B. In this case, there is a switching relationship of activation/deactivation between semi-static configuration group A and semi-static configuration group B. The switching relationship of activation/deactivation may be applied only in the case of activation or only in the case of deactivation.
A configuration group that has the switching relationship of activation/deactivation with another group, such as group B, may be determined by higher layer signaling from the BS. For example, group B, which has the switching relationship of activation/deactivation with group A, may be determined through RRC parameter(s) included in the configuration of group A.
A configuration group that has the switching relationship of activation/deactivation with another group, such as group B, does not always need to have a mutual activation/deactivation switching relationship. For example, even if group B, which has the switching relationship of activation/deactivation with group A, is determined through the RRC parameter(s) included in the configuration of group A, group B may have the switching relationship of activation/deactivation with another group, group C. In such a case, the activation of group A may activate group A and deactivate group B, while the deactivation of group B may activate group C and deactivate group B.
When the UE generates UCI and transmits the UCI on a PUCCH or PUSCH, semi-static configurations may be considered. Specifically, a configured SPS configuration and SPS PDSCH TO, and a positive SR and SR TO may be used by the UE to generate a HARQ-ACK codebook and to multiplex and transmit SR information, respectively. When the UE is capable of activating/deactivating semi-static configurations using Implementation 1, Implementation 2, and/or Implementation 3 described above, the following may be considered.
Different methods such as Method 1 and Method 2 may be used depending on the type of semi-static configuration (SPS, CG, or SR). Alternatively, one of Method 1 or Method 2 may be selected and used based on L1 signaling and/or higher layer signaling from the BS.
According to some implementations of the present disclosure, the UE and BS may activate/deactivate a plurality of semi-static configurations, such as SPS, CG, and SR configurations, through a (activation/deactivation) pattern or L1 indication. Accordingly, various resources required for XR services may be assigned to the UE without latency. Additionally, according to some implementations, switching between two semi-static configuration groups may be supported via a single signal.
The UE may perform operations according to some implementations of the present disclosure in association with downlink signal reception. The UE may include at least one transceiver; at least one processor; and at least one computer memory operably connectable to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations according to some implementations of the present disclosure. A processing device for a UE may include at least one processor; and at least one computer memory operably connectable to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations according to some implementations of the present disclosure. A computer readable (non-transitory) storage medium may store at least one computer program including instructions that, when executed by at least one processor, cause the at least one processor to perform operations according to some implementations of the present disclosure. A computer program or a computer program product may include instructions recorded in at least one computer readable (non-transitory) storage medium and causing, when executed, (at least one processor) to perform operations according to some implementations of the present disclosure. The computer program or the computer program product may be recorded in at least one computer-readable (non-transitory) storage medium and may include instructions that, when executed, cause (at least one processor) to perform operations according to some implementations of the present disclosure. In the UE, the processing device, the computer-readable (non-transitory) storage medium, and/or the computer program product, the operations include receiving a plurality of SPS configurations and pattern configuration information for a cell (S1201). Each of the plurality of SPS configurations may be related to a DL assignment occurring with a specific periodicity. The pattern configuration information may be related to at least one activation pattern that indicates activation or deactivation of each of a plurality of DL assignments occurring within a specific period, based on the plurality of SPS configurations. The operations may include: determining SPS PDSCH occasions based on the plurality of SPS configurations and the pattern configuration information (S1203); and receiving a PDSCH within the SPS PDSCH occasions (S1205).
In some implementations, the pattern configuration information may include information regarding a plurality of different activation patterns.
In some implementations, determining the SPS PDSCH occasions based on the plurality of SPS configurations and the pattern configuration information comprises determining the SPS PDSCH occasions by applying a first activation pattern among the plurality of activation patterns based on a predetermined condition being satisfied.
In some implementations, the predetermined condition may include receiving the PDSCH at an SPS PDSCH occasion determined based on a second activation pattern among the plurality of activation patterns.
In some implementations, the predetermined condition may include receiving DCI including indication information regarding the first activation pattern among the plurality of activation patterns.
In some implementations, the operations may include: generating a HARQ-ACK codebook including a HARQ-ACK information bit for the PDSCH based on the reception of the PDSCH; and transmitting the HARQ-ACK codebook in a slot related to an SPS PDSCH occasion at which the PDSCH is received. In some implementations, the HARQ-ACK codebook may exclude HARQ-ACK information corresponding to an SPS PDSCH occasion not activated by the activation pattern among SPS PDSCH occasions corresponding to the plurality of downlink assignments.
In some implementations, the operations may include: receiving respective activation PDCCHs for the plurality of SPS configurations. In some implementations, the pattern configuration information may be based on SPS configurations activated by the activation PDCCHs.
The BS may perform operations according to some implementations of the present disclosure in association with downlink signal transmission. The BS may include at least one transceiver; at least one processor; and at least one computer memory operably connectable to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations according to some implementations of the present disclosure. A processing device for a BS may include at least one processor; and at least one computer memory operably connectable to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations according to some implementations of the present disclosure. A computer readable (non-transitory) storage medium may store at least one computer program including instructions that, when executed by at least one processor, cause the at least one processor to perform operations according to some implementations of the present disclosure. A computer program or a computer program product may include instructions recorded in at least one computer readable (non-transitory) storage medium and causing, when executed, (at least one processor) to perform operations according to some implementations of the present disclosure. In the BS, the processing device, the computer-readable (non-transitory) storage medium, and/or the computer program product, the operations include transmitting a plurality of SPS configurations and pattern configuration information for a cell (S1301). Each of the plurality of SPS configurations may be related to a DL assignment occurring with a specific periodicity. The pattern configuration information may be related to at least one activation pattern that indicates activation or deactivation of each of a plurality of DL assignments occurring within a specific period, based on the plurality of SPS configurations. The operations may include: determining SPS PDSCH occasions based on the plurality of SPS configurations and the pattern configuration information (S1303); and transmitting a PDSCH within the SPS PDSCH occasions (S1305).
In some implementations, the pattern configuration information may include information regarding a plurality of different activation patterns.
In some implementations, determining the SPS PDSCH occasions based on the plurality of SPS configurations and the pattern configuration information comprises determining the SPS PDSCH occasions by applying a first activation pattern among the plurality of activation patterns based on a predetermined condition being satisfied.
In some implementations, the predetermined condition may include transmitting the PDSCH at an SPS PDSCH occasion determined based on a second activation pattern among the plurality of activation patterns.
In some implementations, the predetermined condition may include transmitting DCI including indication information regarding the first activation pattern among the plurality of activation patterns.
In some implementations, the operations may include receiving a HARQ-ACK codebook including a HARQ-ACK information bit for the PDSCH in a slot related to an SPS PDSCH occasion at which the PDSCH is transmitted, based on the transmission of the PDSCH. In some implementations, the HARQ-ACK codebook may exclude HARQ-ACK information corresponding to an SPS PDSCH occasion not activated by the activation pattern among SPS PDSCH occasions corresponding to the plurality of downlink assignments.
In some implementations, the operations may further include transmitting respective activation PDCCHs for the plurality of SPS configurations. In some implementations, the pattern configuration information may be based on SPS configurations activated by the activation PDCCHs.
The examples of the present disclosure as described above have been presented to enable any person of ordinary skill in the art to implement and practice the present disclosure. Although the present disclosure has been described with reference to the examples, those skilled in the art may make various modifications and variations in the example of the present disclosure. Thus, the present disclosure is not intended to be limited to the examples set for the herein, but is to be accorded the broadest scope consistent with the principles and features disclosed herein.
The implementations of the present disclosure may be used in a BS, a UE, or other equipment in a wireless communication system.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2022-0053035 | Apr 2022 | KR | national |
This application is a National Phase application under 35 U.S.C. 371 of International Application No. PCT/KR2023/005862, filed on Apr. 28, 2023, which claims the benefit of Korean Patent Application No. 10-2022-0053035, filed on Apr. 28, 2022, the contents of which are incorporated by reference herein in their entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/KR2023/005862 | 4/28/2023 | WO |
