Patent Application
20240276463
This disclosure relates to a wireless communication system.
Sidelink (SL) communication is a communication scheme in which a direct link is established between User Equipments (UEs) and the UEs exchange voice and data directly with each other without intervention of a base station. SL communication is under consideration as a solution to the overhead of a base station caused by rapidly increasing data traffic. Vehicle-to-everything (V2X) refers to a communication technology through which a vehicle exchanges information with another vehicle, a pedestrian, an object having an infrastructure (or infra) established therein, and so on. The V2X may be divided into 4 types, such as vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), vehicle-to-network (V2N), and vehicle-to-pedestrian (V2P). The V2X communication may be provided via a PCS interface and/or Uu interface.
Meanwhile, as a wider range of communication devices require larger communication capacities, the need for mobile broadband communication that is more enhanced than the existing Radio Access Technology (RAT) is rising. Accordingly, discussions are made on services and user equipment (UE) that are sensitive to reliability and latency. And, a next generation radio access technology that is based on the enhanced mobile broadband communication, massive Machine Type Communication (MTC), Ultra-Reliable and Low Latency Communication (URLLC), and so on, may be referred to as a new radio access technology (RAT) or new radio (NR). Herein, the NR may also support vehicle-to-everything (V2X) communication.
Regarding V2X communication, a scheme of providing a safety service, based on a V2X message such as Basic Safety Message (BSM). Cooperative Awareness Message (CAM), and Decentralized Environmental Notification Message (DENM) is focused in the discussion on the RAT used before the NR. The V2X message may include position information, dynamic information, attribute information, or the like. For example, a UE may transmit a periodic message type CAM and/or an event triggered message type DENM to another UE.
Thereafter, regarding V2X communication, various V2X scenarios are proposed in NR. For example, the various V2X scenarios may include vehicle platooning, advanced driving, extended sensors, remote driving, or the like.
Meanwhile, if a transmission time interval (TTI) is different between long term evolution (LTE) SL and NR SL, a transient period may occur in the middle of LTE SL or NR SL transmission if the UE transmits LTE SL and NR SL simultaneously. From the perspective of reception of the UE, additional automatic gain control (AGC) may be required in the middle of LTE SL or NR SL reception, or AGC performed only at the front end of reception may operate inefficiently. More specifically, if the UE has performed AGC on the first symbol in a subframe of LTE SL, and NR SL transmission starts in the middle of LTE SL reception, some signals (exceeding the maximum reception power configured by AGC) may be clipped due to a sudden increase in the total received power.
In an embodiment, provided is a method for performing wireless communication by a first device. The method may comprise: obtaining information related to a first resource pool for long term evolution (LTE) sidelink (SL) communication; obtaining information related to a second resource pool for NR SL communication; triggering resource selection in a first slot; determining a selection window based on the first slot and a packet delay budget (PDB); and selecting, based on sensing, a first SL resource among slots belonging to the second resource pool within the selection window, wherein the first SL resource is a resource included in a slot that overlaps in time domain with a start of a first subframe within the first resource pool.
In an embodiment, provided is a first device adapted to perform wireless communication. The first device may comprise: one or more memories storing instructions; one or more transceivers; and one or more processors connected to the one or more memories and the one or more transceivers. For example, the one or more processors may execute the instructions to: obtain information related to a first resource pool for long term evolution (LTE) sidelink (SL) communication; obtain information related to a second resource pool for NR SL communication; trigger resource selection in a first slot; determine a selection window based on the first slot and a packet delay budget (PDB); and select, based on sensing, a first SL resource among slots belonging to the second resource pool within the selection window, wherein the first SL resource is a resource included in a slot that overlaps in time domain with a start of a first subframe within the first resource pool.
In an embodiment, provided is a processing device adapted to control a first device performing wireless communication. The processing device may comprise: one or more processors; and one or more memories operably connected to the one or more processors and storing instructions. The one or more processors may execute the instructions to: obtain information related to a first resource pool for long term evolution (LTE) sidelink (SL) communication; obtain information related to a second resource pool for NR SL communication; trigger resource selection in a first slot; determine a selection window based on the first slot and a packet delay budget (PDB); and select, based on sensing, a first SL resource among slots belonging to the second resource pool within the selection window, wherein the first SL resource is a resource included in a slot that overlaps in time domain with a start of a first subframe within the first resource pool.
SL communication based on different RATs can coexist efficiently.
In the present disclosure, “A or B” may mean “only A”, “only B” or “both A and B.” In other words, in the present disclosure. “A or B” may be interpreted as “A and/or B”. For example, in the present disclosure, “A, B, or C” may mean “only A”, “only B”. “only C”, or “any combination of A, B, C”.
A slash (/) or comma used in the present disclosure may mean “and/or”. For example, “A/B” may mean “A and/or B”. Accordingly, “A/B” may mean “only A”, “only B”, or “both A and B”. For example, “A, B, C” may mean “A, B, or C”.
In the present disclosure, “at least one of A and B” may mean “only A”, “only B”, or “both A and B”. In addition, in the present disclosure, the expression “at least one of A or B” or “at least one of A and/or B” may be interpreted as “at least one of A and B”.
In addition, in the present disclosure, “at least one of A, B, and C” may mean “only A”, “only B”, “only C”, or “any combination of A, B, and C”. In addition, “at least one of A, B. or C” or “at least one of A, B, and/or C” may mean “at least one of A, B, and C”.
In addition, a parenthesis used in the present disclosure may mean “for example”. Specifically, when indicated as “control information (PDCCH)”, it may mean that “PDCCH” is proposed as an example of the “control information”. In other words, the “control information” of the present disclosure is not limited to “PDCCH”, and “PDCCH” may be proposed as an example of the “control information”. In addition, when indicated as “control information (i.e., PDCCH)”, it may also mean that “PDCCH” is proposed as an example of the “control information”.
A technical feature described individually in one figure in the present disclosure may be individually implemented, or may be simultaneously implemented.
The technology described below may be used in various wireless communication systems such as code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), single carrier frequency division multiple access (SC-FDMA), and so on. The CDMA may be implemented with a radio technology, such as universal terrestrial radio access (UTRA) or CDMA-2000. The TDMA may be implemented with a radio technology, such as global system for mobile communications (GSM)/general packet ratio service (GPRS)/enhanced data rate for GSM evolution (EDGE). The OFDMA may be implemented with a 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), and so on. IEEE 802.16m is an evolved version of IEEE 802.16e and provides backward compatibility with a system based on the IEEE 802.16e. The UTRA is part of a universal mobile telecommunication system (UMTS). 3rd generation partnership project (3GPP) long term evolution (LTE) is part of an evolved UMTS (E-UMTS) using the E-UTRA. The 3GPP LTE uses the OFDMA in a downlink and uses the SC-FDMA in an uplink. LTE-advanced (LTE-A) is an evolution of the LTE.
5G NR is a successive technology of LTE-A corresponding to a new Clean-slate type mobile communication system having the characteristics of high performance, low latency, high availability, and so on. 5G NR may use resources of all spectrum available for usage including low frequency bands of less than 1 GHz, middle frequency bands ranging from 1 GHz to 10 GHz, high frequency (millimeter waves) of 24 GHz or more, and so on.
For clarity in the description, the following description will mostly focus on LTE-A or 5G NR. However, technical features according to an embodiment of the present disclosure will not be limited only to this.
Referring to
The embodiment of
Layers of a radio interface protocol between the UE and the network can be classified into a first layer (layer 1, L1), a second layer (layer 2, L2), and a third layer (layer 3, L3) based on the lower three layers of the open system interconnection (OST) model that is well-known in the communication system. Among them, a physical (PHY) layer belonging to the first layer provides an information transfer service by using a physical channel, and a radio resource control (RRC) layer belonging to the third layer serves to control a radio resource between the UE and the network. For this, the RRC layer exchanges an RRC message between the UE and the BS.
Referring to
Between different physical layers, i.e., a physical layer of a transmitter and a physical layer of a receiver, data are transferred through the physical channel. The physical channel is modulated using an orthogonal frequency division multiplexing (OFDM) scheme, and utilizes time and frequency as a radio resource.
The MAC layer provides services to a radio link control (RLC) layer, which is a higher layer of the MAC layer, via a logical channel. The MAC layer provides a function of mapping multiple logical channels to multiple transport channels. The MAC layer also provides a function of logical channel multiplexing by mapping multiple logical channels to a single transport channel. The MAC layer provides data transfer services over logical channels.
The RLC layer performs concatenation, segmentation, and reassembly of Radio Link Control Service Data Unit (RLC SDU). In order to ensure diverse quality of service (QoS) required by a radio bearer (RB), the RLC layer provides three types of operation modes, i.e., a transparent mode (TM), an unacknowledged mode (UM), and an acknowledged mode (AM). An AM RLC provides error correction through an automatic repeat request (ARQ).
A radio resource control (RRC) layer is defined only in the control plane. The RRC layer serves to control the logical channel, the transport channel, and the physical channel in association with configuration, reconfiguration and release of RBs. The RB is a logical path provided by the first layer (i.e., the physical layer or the PHY layer) and the second layer (i.e., a MAC layer, an RLC layer, a packet data convergence protocol (PDCP) layer, and a service data adaptation protocol (SDAP) layer) for data delivery between the UE and the network.
Functions of a packet data convergence protocol (PDCP) layer in the user plane include user data delivery, header compression, and ciphering. Functions of a PDCP layer in the control plane include control-plane data delivery and ciphering/integrity protection.
A service data adaptation protocol (SDAP) layer is defined only in a user plane. The SDAP layer performs mapping between a Quality of Service (QOS) flow and a data radio bearer (DRB) and QoS flow ID (QFI) marking in both DL and UL packets.
The configuration of the RB implies a process for specifying a radio protocol layer and channel properties to provide a particular service and for determining respective detailed parameters and operations. The RB can be classified into two types, i.e., a signaling RB (SRB) and a data RB (DRB). The SRB is used as a path for transmitting an RRC message in the control plane. The DRB is used as a path for transmitting user data in the user plane.
When an RRC connection is established between an RRC layer of the UE and an RRC layer of the E-UTRAN, the UE is in an RRC_CONNECTED state, and, otherwise, the UE may be in an RRC_IDLE state. In case of the NR, an RRC_INACTIVE state is additionally defined, and a UE being in the RRC_INACTIVE state may maintain its connection with a core network whereas its connection with the BS is released.
Data is transmitted from the network to the UE through a downlink transport channel. Examples of the downlink transport channel include a broadcast channel (BCH) for transmitting system information and a downlink-shared channel (SCH) for transmitting user traffic or control messages. Traffic of downlink multicast or broadcast services or the control messages can be transmitted on the downlink-SCH or an additional downlink multicast channel (MCH). Data is transmitted from the UE to the network through an uplink transport channel. Examples of the uplink transport channel include a random access channel (RACH) for transmitting an initial control message and an uplink SCH for transmitting user traffic or control messages.
Examples of logical channels belonging to a higher channel of the transport channel and mapped onto the transport channels include a broadcast channel (BCCH), a paging control channel (PCCH), a common control channel (CCCH), a multicast control channel (MCCH), a multicast traffic channel (MTCH), etc.
Referring to
In case of using a normal CP, each slot may include 14 symbols. In case of using an extended CP, each slot may include 12 symbols. Herein, a symbol may include an OFDM symbol (or CP-OFDM symbol) and a Single Carrier-FDMA (SC-FDMA) symbol (or Discrete Fourier Transform-spread-OFDM (DFT-s-OFDM) symbol).
Table 1 shown below represents an example of a number of symbols per slot (Nslotsymb), a number slots per frame (Nframe,uslot), and a number of slots per subframe (Nsubframe,uslot) based on an SCS configuration (u), in a case where a normal CP is used.
Table 2 shows an example of a number of symbols per slot, a number of slots per frame, and a number of slots per subframe based on the SCS, in a case where an extended CP is used.
In an NR system, OFDM(A) numerologies (e.g., SCS, CP length, and so on) between multiple cells being integrate to one UE may be differently configured. Accordingly, a (absolute time) duration (or section) of a time resource (e.g., subframe, slot or TTI) (collectively referred to as a time unit (TU) for simplicity) being configured of the same number of symbols may be differently configured in the integrated cells.
In the NR, multiple numerologies or SCSs for supporting diverse 5G services may be supported. For example, in case an SCS is 15 kHz, a wide area of the conventional cellular bands may be supported, and, in case an SCS is 30 KHz/60 kHz a dense-urban, lower latency, wider carrier bandwidth may be supported. In case the SCS is 60 kHz or higher, a bandwidth that is greater than 24.25 GHz may be used in order to overcome phase noise.
An NR frequency band may be defined as two different types of frequency ranges. The two different types of frequency ranges may be FR1 and FR2. The values of the frequency ranges may be changed (or varied), and, for example, the two different types of frequency ranges may be as shown below in Table 3. Among the frequency ranges that are used in an NR system. FR1 may mean a “sub 6 GHz range”, and FR2 may mean an “above 6 GHz range” and may also be referred to as a millimeter wave (mmW).
As described above, the values of the frequency ranges in the NR system may be changed (or varied). For example, as shown below in Table 4, FR1 may include a band within a range of 410 MHz to 7125 MHz. More specifically, FR1 may include a frequency band of 6 GHz (or 5850, 5900, 5925 MHz, and so on) and higher. For example, a frequency band of 6 GHz (or 5850, 5900, 5925 MHz, and so on) and higher being included in FR1 mat include an unlicensed band. The unlicensed band may be used for diverse purposes, e.g., the unlicensed band for vehicle-specific communication (e.g., automated driving).
Referring to
A carrier includes a plurality of subcarriers in a frequency domain. A Resource Block (RB) may be defined as a plurality of consecutive subcarriers (e.g., 12 subcarriers) in the frequency domain. A Bandwidth Part (BWP) may be defined as a plurality of consecutive (Physical) Resource Blocks ((P)RBs) in the frequency domain, and the BWP may correspond to one numerology (e.g., SCS, CP length, and so on). A carrier may include a maximum of N number BWPs (e.g., 5 BWPs). Data communication may be performed via an activated BWP. Each element may be referred to as a Resource Element (RE) within a resource grid and one complex symbol may be mapped to each element.
Hereinafter, a bandwidth part (BWP) and a carrier will be described.
The BWP may be a set of consecutive physical resource blocks (PRBs) in a given numerology. The PRB may be selected from consecutive sub-sets of common resource blocks (CRBs) for the given numerology on a given carrier
For example, the BWP may be at least any one of an active BWP, an initial BWP, and/or a default BWP. For example, the UE may not monitor downlink radio link quality in a DL BWP other than an active DL BWP on a primary cell (PCell). For example, the UE may not receive PDCCH, physical downlink shared channel (PDSCH), or channel state information-reference signal (CSI-RS) (excluding RRM) outside the active DL BWP. For example, the UE may not trigger a channel state information (CSI) report for the inactive DL BWP. For example, the UE may not transmit physical uplink control channel (PUCCH) or physical uplink shared channel (PUSCH) outside an active UL BWP. For example, in a downlink case, the initial BWP may be given as a consecutive RB set for a remaining minimum system information (RMSI) control resource set (CORESET) (configured by physical broadcast channel (PBCH)). For example, in an uplink case, the initial BWP may be given by system information block (SIB) for a random access procedure. For example, the default BWP may be configured by a higher layer. For example, an initial value of the default BWP may be an initial DL BWP. For energy saving, if the UE fails to detect downlink control information (DCI) during a specific period, the UE may switch the active BWP of the UE to the default BWP
Meanwhile, the BWP may be defined for SL. The same SL BWP may be used in transmission and reception. For example, a transmitting UE may transmit an SL channel or an SL signal on a specific BWP, and a receiving UE may receive the SL channel or the SL signal on the specific BWP. In a licensed carrier, the SL BWP may be defined separately from a Uu BWP, and the SL BWP may have configuration signaling separate from the Uu BWP. For example, the UE may receive a configuration for the SL BWP from the BS/network. For example, the UE may receive a configuration for the Uu BWP from the BS/network. The SL BWP may be (pre-)configured in a carrier with respect to an out-of-coverage NR V2X UE and an RRC_IDLE UE. For the UE in the RRC_CONNECTED mode, at least one SL BWP may be activated in the carrier.
Referring to
The BWP may be configured by a point A, an offset NstartBWP from the point A. and a bandwidth NsizeBWP. For example, the point A may be an external reference point of a PRB of a carrier in which a subcarrier 0 of all numerologies (e.g., all numerologies supported by a network on that carrier) is aligned. For example, the offset may be a PRB interval between a lowest subcarrier and the point A in a given numerology. For example, the bandwidth may be the number of PRBs in the given numerology.
Hereinafter, V2X or SL communication will be described.
A sidelink synchronization signal (SLSS) may include a primary sidelink synchronization signal (PSSS) and a secondary sidelink synchronization signal (SSSS), as an SL-specific sequence. The PSSS may be referred to as a sidelink primary synchronization signal (S-PSS), and the SSSS may be referred to as a sidelink secondary synchronization signal (S-SSS). For example, length-127 M-sequences may be used for the S-PSS, and length-127 gold sequences may be used for the S-SSS. For example, a UE may use the S-PSS for initial signal detection and for synchronization acquisition. For example, the UE may use the S-PSS and the S-SSS for acquisition of detailed synchronization and for detection of a synchronization signal ID.
A physical sidelink broadcast channel (PSBCH) may be a (broadcast) channel for transmitting default (system) information which must be first known by the UE before SL signal transmission/reception. For example, the default information may be information related to SLSS, a duplex mode (DM), a time division duplex (TDD) uplink/downlink (UL/DL) configuration, information related to a resource pool, a type of an application related to the SLSS, a subframe offset, broadcast information, or the like. For example, for evaluation of PSBCH performance, in NR V2X, a payload size of the PSBCH may be 56 bits including 24-bit cyclic redundancy check (CRC).
The S-PSS, the S-SSS, and the PSBCH may be included in a block format (e.g., SL synchronization signal (SS)/PSBCH block, hereinafter, sidelink-synchronization signal block (S-SSB)) supporting periodical transmission. The S-SSB may have the same numerology (i.e., SCS and CP length) as a physical sidelink control channel (PSCCH)/physical sidelink shared channel (PSSCH) in a carrier, and a transmission bandwidth may exist within a (pre-)configured sidelink (SL) BWP. For example, the S-SSB may have a bandwidth of 11 resource blocks (RBs). For example, the PSBCH may exist across 11 RBs. In addition, a frequency position of the S-SSB may be (pre-)configured. Accordingly, the UE does not have to perform hypothesis detection at frequency to discover the S-SSB in the carrier.
Referring to
For example, the UE 1 may select a resource unit corresponding to a specific resource in a resource pool which implies a set of series of resources. In addition, the UE 1 may transmit an SL signal by using the resource unit. For example, a resource pool in which the UE 1 is capable of transmitting a signal may be configured to the UE 2 which is a receiving UE, and the signal of the UE 1 may be detected in the resource pool.
Herein, if the UE 1 is within a connectivity range of the BS, the BS may inform the UE 1 of the resource pool. Otherwise, if the UE 1 is out of the connectivity range of the BS, another UE may inform the UE 1 of the resource pool, or the UE 1 may use a pre-configured resource pool.
In general, the resource pool may be configured in unit of a plurality of resources, and each UE may select a unit of one or a plurality of resources to use it in SL signal transmission thereof.
Hereinafter, resource allocation in SL will be described.
For example, (a) of
For example, (b) of
Referring to (a) of
Referring to (b) of
For example, the UE may assist the SL resource selection for another UE. For example, in the NR resource allocation mode 2, the UE may be provided/allocated with a configured grant for SL transmission. For example, in the NR resource allocation mode 2, the UE may schedule SL transmission of another UE. For example, in the NR resource allocation mode 2, the UE may reserve an SL resource for blind retransmission.
For example, in the NR resource allocation mode 2, the UE 1 may use the SCI to indicate a priority of SL transmission to the UE 2. For example, the UE 2 may decode the SCI, and the UE 2 may perform sensing and/or resource (re)selection on the basis of the priority. For example, the resource (re)selection procedure may include a step in which the UE 2 identifies a candidate resource in a resource selection window and a step in which the UE 2 selects a resource for (re)transmission among the identified candidate resources. For example, the resource selection window may be a time interval for selecting a resource for SL transmission by the UE. For example, after the UE 2 triggers resource (re)selection, the resource selection window may start at T1≥0, and the resource selection window may be restricted by a remaining packet delay budget of the UE 2. For example, in the step in which the UE 2 identifies the candidate resource in the resource selection window, if a specific resource is indicated by the SCI received by the UE 2 from the UE 1 and if an L1 SL RSRP threshold for the specific resource exceeds an SL RSRP threshold, the UE 2 may not determine the specific resource as the candidate resource. For example, the SL RSRP threshold may be determined based on a priority of SL transmission indicated by the SCI received by the UE 2 from the UE 1 and a priority of SL transmission on a resource selected by the UE 2.
For example, the L1 SL RSRP may be measured based on an SL demodulation reference signal (DMRS). For example, one or more PSSCH DMRS patterns may be configured or pre-configured in a time domain for each resource pool. For example, a PDSCH DMRS configuration type 1 and/or type 2 may be identical or similar to a frequency domain pattern of the PSSCH DMRS. For example, a correct DMRS pattern may be indicated by the SCI. For example, in the NR resource allocation mode 2, the transmitting UE may select a specific DMRS pattern from among configured or pre-configured DMRS patterns for the resource pool.
For example, in the NR resource allocation mode 2, the transmitting UE may perform initial transmission of a transport block (TB) without reservation, based on the sensing and resource (re)selection procedure. For example, the transmitting UE may use an SCI related to a first/initial RB to reserve an SL resource for initial transmission of a second TB, based on the sensing and resource (re)selection procedure.
For example, in the NR resource allocation mode 2, the UE may reserve a resource for feedback-based PSSCH retransmission, through signaling related to previous transmission of the same TB. For example, the maximum number of SL resources reserved by one transmission including current transmission may be 2, 3, or 4. For example, the maximum number of SL resources may be identical irrespective of whether HARQ feedback is enabled. For example, the maximum number of HARQ (re)transmissions for one TB may be restricted by a configuration or a pre-configuration. For example, the maximum number of HARQ (re)transmissions may be up to 32. For example, in the absence of the configuration or the pre-configuration, the maximum number of HARQ (re)transmissions may not be designated. For example, the configuration or the pre-configuration may be for the transmitting UE. For example, in the NR resource allocation mode 2, HARQ feedback for releasing a resource not used by the UE may be supported.
For example, in the NR resource allocation mode 2, the UE may use the SCI to indicate to another UE one or more sub-channels and/or slots used by the UE. For example, the UE may use the SCI to indicate to another UE one or more sub-channels and/or slots reserved by the UE for PSSCH (re)transmission. For example, a minimum allocation unit of an SL resource may be a slot. For example, a size of a sub-channel may be configured for the UE or may be pre-configured.
Hereinafter, a hybrid automatic repeat request (HARQ) procedure will be described.
In case of SL unicast and groupcast. HARQ feedback and HARQ combining in the physical layer may be supported. For example, when a receiving UE operates in a resource allocation mode 1 or 2, the receiving UE may receive the PSSCH from a transmitting UE, and the receiving UE may transmit HARQ feedback for the PSSCH to the transmitting UE by using a sidelink feedback control information (SFCI) format through a physical sidelink feedback channel (PSFCH).
For example, the SL HARQ feedback may be enabled for unicast. In this case, in a non-code block group (non-CBG) operation, if the receiving UE decodes a PSCCH of which a target is the receiving UE and if the receiving UE successfully decodes a transport block related to the PSCCH, the receiving UE may generate HARQ-ACK. In addition, the receiving UE may transmit the HARQ-ACK to the transmitting UE. Otherwise, if the receiving UE cannot successfully decode the transport block after decoding the PSCCH of which the target is the receiving UE, the receiving UE may generate the HARQ-NACK. In addition, the receiving UE may transmit HARQ-NACK to the transmitting UE.
For example, the SL HARQ feedback may be enabled for groupcast. For example, in the non-CBG operation, two HARQ feedback options may be supported for groupcast.
(1) Groupcast option 1: After the receiving UE decodes the PSCCH of which the target is the receiving UE, if the receiving UE fails in decoding of a transport block related to the PSCCH, the receiving UE may transmit HARQ-NACK to the transmitting UE through a PSFCH. Otherwise, if the receiving UE decodes the PSCCH of which the target is the receiving UE and if the receiving UE successfully decodes the transport block related to the PSCCH, the receiving UE may not transmit the HARQ-ACK to the transmitting UE.
(2) Groupcast option 2: After the receiving UE decodes the PSCCH of which the target is the receiving UE, if the receiving UE fails in decoding of the transport block related to the PSCCH, the receiving UE may transmit HARQ-NACK to the transmitting UE through the PSFCH. In addition, if the receiving UE decodes the PSCCH of which the target is the receiving UE and if the receiving UE successfully decodes the transport block related to the PSCCH, the receiving UE may transmit the HARQ-ACK to the transmitting UE through the PSFCH.
For example, if the groupcast option 1 is used in the SL HARQ feedback, all UEs performing groupcast communication may share a PSFCH resource. For example, UEs belonging to the same group may transmit HARQ feedback by using the same PSFCH resource.
For example, if the groupcast option 2 is used in the SL HARQ feedback, each UE performing groupcast communication may use a different PSFCH resource for HARQ feedback transmission. For example, UEs belonging to the same group may transmit HARQ feedback by using different PSFCH resources.
For example, when the SL HARQ feedback is enabled for groupcast, the receiving UE may determine whether to transmit the HARQ feedback to the transmitting UE based on a transmission-reception (TX-RX) distance and/or reference signal received power (RSRP).
For example, in the groupcast option 1, in case of the TX-RX distance-based HARQ feedback, if the TX-RX distance is less than or equal to a communication range requirement, the receiving UE may transmit HARQ feedback for the PSSCH to the transmitting UE. Otherwise, if the TX-RX distance is greater than the communication range requirement, the receiving UE may not transmit the HARQ feedback for the PSSCH to the transmitting UE. For example, the transmitting UE may inform the receiving UE of a location of the transmitting UE through SCI related to the PSSCH. For example, the SCI related to the PSSCH may be second SCI. For example, the receiving UE may estimate or obtain the TX-RX distance based on a location of the receiving UE and the location of the transmitting UE. For example, the receiving UE may decode the SCI related to the PSSCH and thus may know the communication range requirement used in the PSSCH.
For example, in case of the resource allocation mode 1, a time (offset) between the PSFCH and the PSSCH may be configured or pre-configured. In case of unicast and groupcast, if retransmission is necessary on SL, this may be indicated to a BS by an in-coverage UE which uses the PUCCH. The transmitting UE may transmit an indication to a serving BS of the transmitting UE in a form of scheduling request (SR)/buffer status report (BSR), not a form of HARQ ACK/NACK In addition, even if the BS does not receive the indication, the BS may schedule an SL retransmission resource to the UE. For example, in case of the resource allocation mode 2, a time (offset) between the PSFCH and the PSSCH may be configured or pre-configured.
For example, from a perspective of UE transmission in a carrier, TDM between the PSCCH/PSSCH and the PSFCH may be allowed for a PSFCH format for SL in a slot. For example, a sequence-based PSFCH format having a single symbol may be supported. Herein, the single symbol may not an AGC duration. For example, the sequence-based PSFCH format may be applied to unicast and groupcast.
For example, in a slot related to a resource pool, a PSFCH resource may be configured periodically as N slot durations, or may be pre-configured. For example, N may be configured as one or more values greater than or equal to 1. For example, N may be 1, 2, or 4. For example, HARQ feedback for transmission in a specific resource pool may be transmitted only through a PSFCH on the specific resource pool.
For example, if the transmitting UE transmits the PSSCH to the receiving UE across a slot #X to a slot #N, the receiving UE may transmit HARQ feedback for the PSSCH to the transmitting UE in a slot #(N+A). For example, the slot #(N+A) may include a PSFCH resource. Herein, for example, A may be a smallest integer greater than or equal to K. For example, K may be the number of logical slots. In this case, K may be the number of slots in a resource pool. Alternatively, for example, K may be the number of physical slots. In this case, K may be the number of slots inside or outside the resource pool.
For example, if the receiving UE transmits HARQ feedback on a PSFCH resource in response to one PSSCH transmitted by the transmitting UE to the receiving UE, the receiving UE may determine a frequency domain and/or code domain of the PSFCH resource based on an implicit mechanism in a configured resource pool. For example, the receiving UE may determine the frequency domain and/or code domain of the PSFCH resource, based on at least one of a slot index related to PSCCH/PSSCH/PSFCH, a sub-channel related to PSCCH/PSSCH, and/or an identifier for identifying each receiving UE in a group for HARQ feedback based on the groupcast option 2. Additionally/alternatively, for example, the receiving UE may determine the frequency domain and/or code domain of the PSFCH resource, based on at least one of SL RSRP, SINR, L1 source ID, and/or location information.
For example, if HARQ feedback transmission through the PSFCH of the UE and HARQ feedback reception through the PSFCH overlap, the UE may select any one of HARQ feedback transmission through the PSFCH and HARQ feedback reception through the PSFCH based on a priority rule. For example, the priority rule may be based on at least priority indication of the related PSCCH/PSSCH.
For example, if HARQ feedback transmission of a UE through a PSFCH for a plurality of UEs overlaps, the UE may select specific HARQ feedback transmission based on the priority rule. For example, the priority rule may be based on at least priority indication of the related PSCCH/PSSCH.
Hereinafter, sidelink control information (SCI) will be described.
Control information transmitted by a BS to a UE through a PDCCH may be referred to as downlink control information (DCI), whereas control information transmitted by the UE to another UE through a PSCCH may be referred to as SCI. For example, the UE may know in advance a start symbol of the PSCCH and/or the number of symbols of the PSCCH, before decoding the PSCCH. For example, the SCI may include SL scheduling information. For example, the UE may transmit at least one SCI to another UE to schedule the PSSCH. For example, one or more SCI formats may be defined.
For example, a transmitting UE may transmit the SCI to a receiving UE on the PSCCH. The receiving UE may decode one SCI to receive the PSSCH from the transmitting UE.
For example, the transmitting UE may transmit two consecutive SCIs (e.g., 2-stage SCI) to the receiving UE on the PSCCH and/or the PSSCH. The receiving UE may decode the two consecutive SCIs (e.g., 2-stage SCI) to receive the PSSCH from the transmitting UE. For example, if SCI configuration fields are divided into two groups in consideration of a (relatively) high SCI payload size. SCI including first SCI configuration field group may be referred to as first SCI or 1st SCI, and SCI including second SCI configuration field group may be referred to as second SCI or 2nd SCI. For example, the transmitting UE may transmit the first SCI to the receiving UE through the PSCCH. For example, the transmitting UE may transmit the second SCI to the receiving UE on the PSCCH and/or the PSSCH. For example, the second SCI may be transmitted to the receiving UE through an (independent) PSCCH, or may be transmitted in a piggyback manner together with data through the PSSCH. For example, two consecutive SCIs may also be applied to different transmissions (e.g., unicast, broadcast, or groupcast).
For example, the transmitting UE may transmit the entirety or part of information described below to the receiving UE through the SCI. Herein, for example, the transmitting UE may transmit the entirety or part of the information described below to the receiving UE through the first SCI and/or the second SCI.
For example, the first SCI may include information related to channel sensing. For example, the receiving UE may decode the second SCI by using a PSSCH DMRS. A polar code used in a PDCCH may be applied to the second SCI. For example, in a resource pool, a payload size of the first SCI may be identical for unicast, groupcast, and broadcast. After decoding the first SCI, the receiving UE does not have to perform blind decoding of the second SCI. For example, the first SCI may include scheduling information of the second SCI.
Meanwhile, in various embodiments of the present disclosure, since a transmitting UE may transmit at least one of SCI, first SCI, and/or second SCI to a receiving UE through a PSCCH, the PSCCH may be replaced/substituted with at least one of the SCI, the first SCI and/or the second SCI. Additionally/alternatively, for example, the SCI may be replaced/substituted with at least one of the PSCCH, the first SCI, and/or the second SCI. Additionally/alternatively, for example, since a transmitting UE may transmit second SCI to a receiving UE through a PSSCH, the PSSCH may be replaced/substituted with the second SCI.
In the present disclosure, the term “configuration/configured or definition/defined” may be interpreted as being (pre-)configured from the base station or the network (through predefined signaling (e.g., SIB, MAC signaling. RRC signaling)). For example, “A may be configured” may include “that the base station or the network (pre-)configures/defines or informs A to the UE”. Alternatively, the term “configuration/configured or definition/defined” may be interpreted as being pre-configured or pre-defined in the system. For example, “A may be configured” may include “that A is pre-configured/defined in the system”.
A resource pool may be a set of time-frequency resources that can be used for SL transmission and/or SL reception. From the perspective of the UE, the time domain resources within the resource pool may be non-contiguous. A plurality of resource pools may be (pre-)configured for the UE within a single carrier. From the perspective of a physical layer, the UE may perform unicast communication, groupcast communication, and broadcast communication, using a configured or pre-configured resource pool.
Meanwhile, in the next-generation system, the UE may be allowed to transmit and/or receive sidelink channels/signals based on different RATs (e.g., LTE and/or NR) on a single carrier or cell. In embodiments of the present disclosure, the above situation can be extended to a case where the UE simultaneously performs sidelink transmit and receive operations based on a plurality of different RATs with a single RF device and/or a single baseband (BB) device. Meanwhile, depending on RAT, waveform and/or signal generation method and/or direct current (DC) location and/or subcarrier spacing (SCS) and/or subcarrier offset and/or CP length, etc. for sidelink transmission and reception or transmission and reception for PSCCH and/or PSSCH may be different. More specifically, in the case of LTE sidelink, SC-FDMA or DFT-PRECODED OFDM scheme may be used, and the SCS may be 15 kHz. and the DC location may have a subcarrier offset with 7.5 KHz in the center of the system bandwidth, and the CP length can be normal CP and extended CP. On the other hand, in the case of NR sidelink. OFDM or CP-OFDM scheme may be used, and the SCS may be 15 kHz. 30 kHz. 60 kHz. 120 KHz, etc. depending on the (pre-)configuration, and the DC location may be a specific subcarrier location within a SL BWP or an RB grid or a specific location outside the SL BWP or the RB grid depending on the (pre-)configuration, and the subcarrier offset can be +7.5 kHz. 0 kHz, −7.5 kHz, depending on the (pre-)configuration, and the CP length can be normal CP, and the CP length can be extended CP only if the SCS is 60 kHz. In addition, in the case of LTE sidelink, all symbols in a subframe or a slot may be available for SL communication, whereas in the case of NR sidelink, only a symbol period equal to the number of SL symbols (hereinafter referred to as SL_SYMBOL_LENGTH) in a slot from a starting SL symbol index (hereinafter referred to as SL_SYMBOL_START) configured in the (pre-)configuration may be available for SL communication.
Meanwhile, if a transmission time interval (TTI) is different between LTE SL and NR SL, a transient period may occur in the middle of LTE SL or NR SL transmission if the UE transmits LTE SL and NR SL simultaneously. From the perspective of reception of the UE, additional automatic gain control (AGC) may be required in the middle of LTE SL or NR SL reception, or AGC performed only at the front end of reception may operate inefficiently. More specifically, if the UE has performed AGC on the first symbol in a subframe of LTE SL, and NR SL transmission starts in the middle of LTE SL reception, some signals (exceeding the maximum reception power configured by AGC) may be clipped due to a sudden increase in the total received power.
Referring to
Specifically, referring to
Alternatively, if there are both LTE SL and NR SL in the first symbol within a subframe or a slot, the UE may perform AGC. In this case, if NR SL is no longer present in the middle of LTE SL reception, the received power of the UE may be relatively small, and the quantization level adjusted by the initial AGC may be inefficient. Accordingly, quantization errors may occur.
Based on various embodiments of the present disclosure, a method for coexisting SL communications based on different RATs and a device supporting the same are described. For convenience of description, the description will focus on the coexistence of LTE SL and NR SL, but the technical ideas of the present disclosure are not limited thereto. The technical ideas of the present disclosure may also apply to coexistence of communications based on different RATs.
For example, if the UE performs sidelink channel/signal transmission and/or reception based on different RATs (e.g., LTE and/or NR) in a single carrier or cell, the UE may expect/determine that LTE SL and NR SL have the same TTI. More specifically, for example, the same TTI may include that SCS of NR SL is the same as SCS of LTE SL (e.g., 15 KHz). For example, the same TTI may include that SL_SYMBOL_START is set to the first symbol (index value 0) in a slot and/or SL_SYMBOL_LENGTH is set to 14 in a SL BWP configuration for NR SL. For example, the same TTI may include that a PSFCH resource is not configured in a resource pool configuration for NR SL (e.g., PSFCH resource period value is 0). For example, the boundary of the TTI for LTE SL and the TTI for NR SL may be aligned. Alternatively, for example, the time difference between boundaries of the TTI for LTE SL and the TTI for NR SL may be less than or equal to a certain level (e.g., 32 usec or equivalent value or CP length).
Referring to
For example, if the UE performs sidelink channel/signal transmission and/or reception based on different RATs (e.g., LTE and/or NR) in a single carrier or cell, a synchronization source for LTE SL and a synchronization source for NR SL may be the same. For example, the UE may inherit synchronization information (e.g., source and/or DFN0 location and/or subframe and/or slot and/or symbol and/or frame boundary, etc.) used for LTE SL operation and use it for NR SL operation. For example, a subframe boundary for LTE SL and a subframe boundary for NR SL may be the same. For example, if the UE performs sidelink channel/signal transmission and/or reception based on different RATs (e.g., LTE and/or NR) in a single carrier or cell, the synchronization source of NR SL may be a base station (e.g., eNB) and/or a GNSS and/or a UE having the GNSS as the synchronization source and/or a UE having the base station (e.g., eNB) as the synchronization source.
For example, if the UE performs sidelink channel/signal transmission and/or reception based on different RATs (e.g., LTE and/or NR) in a single carrier or cell, the UE may apply slot aggregation for NR SL. For example, based on the above slot aggregation method, the boundary of an interval of the aggregated slots and a subframe of LTE SL may be aligned. More specifically, for example, if SCS of NR SL is 30 kHz. NR SL transmission and reception may be performed in the form of aggregating two slots. For example, if SCS of NR SL is 60 KHz, NR SL transmissions and reception may be performed in the form of aggregating four slots. For example, if SCS of NR SL is 120 KHz, NR SL transmissions and reception may be performed in the form of aggregating eight slots. For example, the start of the aggregated slots of NR SL may be aligned with the start of a subframe of LTE SL. For example, the difference value between the start of the aggregated slots of NR SL and the start of the subframe of LTE SL may be less than or equal to a certain level (e.g., 32 usec or equivalent value or CP length). For example, the UE may perform resource selection from a resource pool by changing a unit of a resource pool selection procedure of NR SL from a slot to aggregated slots. For example, the unit of the resource selection of the UE in NR SL may be aggregated slots. In this case, for example, the UE may use all slots in the aggregated slots for SL transmission in NR SL operation. For example, the UE may not use all slots in the aggregated slots for SL transmission in NR SL operation. For example, the UE may not expect to use only some slots for SL transmission. For example, a PSCCH/PSSCH structure and/or whether a PSFCH resource is present may be configured to be the same for all aggregated slots. For example, the start and end symbols for PSCCH/PSSCH resources may be the same for all aggregated slots. For example, in the case of an empty symbol for a TX-RX switching period in the remaining slots except the last slot among the aggregated slots, the UE may perform PSCCH/PSSCH or PSFCH transmission in the symbol corresponding to the TX-RX switching period if the UE performs slot aggregation. For example, in the symbol corresponding to the TX-RX switching period, the UE may perform transmission by inheriting the mapping of the AGC symbol for the PSCCH/PSSCH or PSFCH transmission. For example, in the symbol corresponding to the TX-RX switching period, the UE may perform transmission by inheriting the mapping of the last symbol of the PSCCH/PSSCH or PSFCH actual transmission. For example, in the symbol corresponding to the TX-RX switching period, the UE may transmit dummy data. For example, the UE may apply the slot aggregation for NR SL only for NR SL that overlap with an LTE SL subframe, depending on a resource pool configuration for LTE SL, and the UE may still perform resource selection on a slot-by-slot basis for the remaining NR SL.
Referring to
For example, if the UE performs sidelink channel/signal transmission and/or reception based on different RATs (e.g., LTE and/or NR) in a single carrier or cell, the UE may be restricted to include at least the earliest slot among NR SL slots that overlap with an LTE SL subframe when the UE performs resource selection for NR SL transmission. For example, the NR SL slot subject to the resource selection may be an NR SL slot that overlaps with an AGC symbol in the LTE SL subframe (e.g., the first symbol in the LTE subframe). For example, the NR SL slot subject to the resource selection may be an NR SL slot that includes an AGC symbol in the LTE SL subframe (e.g., the first symbol in the LTE subframe). For example, only if the UE includes the first slot of NR SL slots that overlap with the LTE SL subframe in the resource selection for NR SL transmission, the UE may include the remaining NR SL slots that overlap with the LTE SL subframe in the resource selection. For example, if SCS of NR SL is 60 kHz, there may be four NR SL slots that overlap with an LTE SL subframe, and the UE may include the first slot of the four NR SL slots that is earlier in time in resource selection. In this case, if the UE selects a resource in the first slot as a PSCCH/PSSCH transmission resource, the UE may select all or part of the remaining three NR SL slots as PSCCH/PSSCH transmission resource(s). On the other hand, for example, if the UE does not select the first slot of the four NR SL slots that overlap the LTE SL subframe as the PSCCH/PSSCH transmission resource, the UE may also exclude the remaining three NR SL slots from PSCCH/PSSCH transmission resources. For example, if the UE selects a resource for PSCCH/PSSCH transmission in the first slot of NR SL slots that overlap with an LTE SL subframe, the UE may select the remaining NR SL slots for PSCCH/PSSCH transmission that overlap with the LTE SL subframe by a certain level or more. For example, the certain level may be (pre-)configured for the UE in the form of the number of slots or in the form of a minimum ratio of the number of NR SL slots to be used for transmission to the total number of NR SL slots overlapping with the LTE SL subframe. For example, the UE may apply the above restriction in resource selection for NR SL only for NR SL that overlaps with the LTE SL subframe according to a resource pool configuration for LTE SL, and the UE may perform resource selection for the remaining NR SL without the above restriction.
Referring to
For example, if the UE performs sidelink channel/signal transmission and/or reception based on different RATs (e.g., LTE and/or NR) in a single carrier or cell, the UE performing LTE SL operation may be provided with a configuration (e.g., configuration for a SL BWP and/or configuration for a resource pool, etc.) for NR SL operating on a carrier on which the LTE SL is operating. For example, the UE performing LTE SL operation may be provided with information regarding slots belonging to a resource pool and/or TTI information (e.g., SL_SYMBOL_START and/or SL_SYMBOL_LENGTH) for NR SL operation through the (pre-)configuration or from the base station. In this case, for example, the UE performing LTE SL operation may, based on the resource pool information and the TTI information of the NR SL, configure a duration or a location in which AGC operation is to be further performed when receiving LTE SL. For example, if the UE performs sidelink channel/signal transmission and/or reception based on different RATs (e.g., LTE and/or NR) in a single carrier or cell, the UE performing NR SL operation may receive a configuration (including a configuration for subframes belonging to a resource pool) for LTE SL operating on a carrier on which the NR SL is operating through the (pre-)configuration or from the base station.
Meanwhile, when the UE performs a resource selection procedure in NR SL, if the ratio of the number of available resources to the total number of resources within a resource selection window is less than or equal to (or below) a (pre-)configured X %, the UE may boost an RSRP threshold such that the ratio of available resources is greater than or equal to (or above) X %. For example, if the UE performs sidelink channel/signal transmission and/or reception based on different RATs (e.g., LTE and/or NR) in a single carrier or cell, and if the UE performs a resource selection procedure, the ratio of available resources may be configured to be a ratio of the number of available resources in the first slot overlapping LTE SL subframes to the total number of resources in the first slot overlapping LTE SL subframes within a resource selection window.
In an embodiment of the present disclosure, the above method(s) for mitigating AGC issues when operating SL based on different RATs may be limited to a case where a frequency domain in which LTE SL operates and a frequency domain in which NR SL operates are overlap each other or adjacent to a certain level or less.
In the embodiment of the present disclosure, the case of simultaneous operation of LTE SL and NR SL on the same carrier is described, but the technical ideas of the present disclosure can be extended to a case where other RAT-based SL or V2X and NR SL are operating simultaneously or a case where NR SL are operating simultaneously with different transmission parameters (e.g., SCS and/or subcarrier offset and/or DC location, etc.).
In the embodiment of the present disclosure, the resource selection procedure in NR SL operation may include resource reselection and/or pre-emption operation. Alternatively, the UE may operate by selecting different methods from the above embodiments for resource selection, resource reselection, and pre-emption.
Based on various embodiments of the present disclosure, communication based on different RATs can coexist efficiently. For example, the UE may preferentially select the earliest NR SL slot among a plurality of NR SL slots that overlap with the LTE SL subframe, thereby preventing the clipping problem described above from occurring. In this way, the reliability of communication based on different RATs may be ensured.
Referring to
Referring to
For example, based on that the first SL resource overlapping with the start of the first subframe is selected, the first device may be allowed to select a second SL resource that overlaps in time domain with the first subframe. For example, the second SL resource may be a resource included in a slot that does not overlap in time domain with the start of the first subframe.
For example, based on that a third SL resource overlapping in time domain with a start of a second subframe within the first resource pool is not selected, the first device may not be allowed to select a fourth SL resource that overlaps in time domain with the second subframe. For example, the fourth SL resource may be a resource included in a slot that does not overlap in time domain with the start of the second subframe.
For example, the start of the first subframe may be an initial symbol (the first symbol) within the first subframe.
For example, the first SL resource may include a plurality of aggregated SL resources. For example, a start of the first SL resource including the plurality of aggregated SL resources may be aligned with the start of the first subframe, and an end of the first SL resource including the plurality of aggregated SL resources may be aligned with an end of the first subframe. For example, a difference between a start of the first SL resource including the plurality of aggregated SL resources and the start of the first subframe may be less than or equal to a threshold, and a difference between an end of the first SL resource including the plurality of aggregated SL resources and an end of the first subframe may be less than or equal to the threshold.
For example, a transmission time interval (TTI) for the LTE SL communication may be the same as a TTI for the NR SL communication. For example, sub-carrier spacing (SCS) related to the NR SL communication may be 15 kHz. and a SL bandwidth part (BWP) configuration related to the second resource pool may include SL starting symbol information configured to be 0 and SL symbol length information configured to be 14. For example, a period of a physical sidelink feedback channel (PSFCH) resource within the second resource pool may be configured to be zero.
For example, a synchronization reference for the LTE SL communication and a synchronization reference for the NR SL communication may be the same.
The proposed method can be applied to the device(s) based on various embodiments of the present disclosure. First, the processor 102 of the first device 100 may obtain information related to a first resource pool for long term evolution (LTE) sidelink (SL) communication. In addition, the processor 102 of the first device 100 may obtain information related to a second resource pool for NR SL communication. In addition, the processor 102 of the first device 100 may trigger resource selection in a first slot. In addition, the processor 102 of the first device 100 may determine a selection window based on the first slot and a packet delay budget (PDB). In addition, the processor 102 of the first device 100 may select, based on sensing, a first SL resource among slots belonging to the second resource pool within the selection window. For example, the first SL resource may be a resource included in a slot that overlaps in time domain with a start of a first subframe within the first resource pool.
Based on an embodiment of the present disclosure, a first device adapted to perform wireless communication may be provided. For example, the first device may comprise: one or more memories storing instructions; one or more transceivers; and one or more processors connected to the one or more memories and the one or more transceivers. For example, the one or more processors may execute the instructions to: obtain information related to a first resource pool for long term evolution (LTE) sidelink (SL) communication; obtain information related to a second resource pool for NR SL communication; trigger resource selection in a first slot; determine a selection window based on the first slot and a packet delay budget (PDB); and select, based on sensing, a first SL resource among slots belonging to the second resource pool within the selection window. For example, the first SL resource may be a resource included in a slot that overlaps in time domain with a start of a first subframe within the first resource pool.
Based on an embodiment of the present disclosure, a processing device adapted to control a first device performing wireless communication may be provided. For example, the processing device may comprise: one or more processors; and one or more memories operably connected to the one or more processors and storing instructions. For example, the one or more processors may execute the instructions to: obtain information related to a first resource pool for long term evolution (LTE) sidelink (SL) communication; obtain information related to a second resource pool for NR SL communication; trigger resource selection in a first slot; determine a selection window based on the first slot and a packet delay budget (PDB); and select, based on sensing, a first SL resource among slots belonging to the second resource pool within the selection window. For example, the first SL resource may be a resource included in a slot that overlaps in time domain with a start of a first subframe within the first resource pool.
Based on an embodiment of the present disclosure, a non-transitory computer-readable storage medium storing instructions may be provided. For example, the instructions, when executed, may cause a first device to: obtain information related to a first resource pool for long term evolution (LTE) sidelink (SL) communication; obtain information related to a second resource pool for NR SL communication; trigger resource selection in a first slot; determine a selection window based on the first slot and a packet delay budget (PDB); and select, based on sensing, a first SL resource among slots belonging to the second resource pool within the selection window. For example, the first SL resource may be a resource included in a slot that overlaps in time domain with a start of a first subframe within the first resource pool.
Referring to
For example, based on that the first SL resource overlapping with the start of the first subframe is selected, the first device may be allowed to select a second SL resource that overlaps in time domain with the first subframe. For example, the second SL resource may be a resource included in a slot that does not overlap in time domain with the start of the first subframe.
For example, based on that a third SL resource overlapping in time domain with a start of a second subframe within the first resource pool is not selected, the first device may not be allowed to select a fourth SL resource that overlaps in time domain with the second subframe. For example, the fourth SL resource may be a resource included in a slot that does not overlap in time domain with the start of the second subframe.
For example, the start of the first subframe may be an initial symbol (the first symbol) within the first subframe.
For example, the first SL resource may include a plurality of aggregated SL resources. For example, a start of the first SL resource including the plurality of aggregated SL resources may be aligned with the start of the first subframe, and an end of the first SL resource including the plurality of aggregated SL resources may be aligned with an end of the first subframe. For example, a difference between a start of the first SL resource including the plurality of aggregated SL resources and the start of the first subframe may be less than or equal to a threshold, and a difference between an end of the first SL resource including the plurality of aggregated SL resources and an end of the first subframe may be less than or equal to the threshold.
For example, a transmission time interval (TTI) for the LTE SL communication may be the same as a TTI for the NR SL communication. For example, sub-carrier spacing (SCS) related to the NR SL communication may be 15 KHz, and a SL bandwidth part (BWP) configuration related to the second resource pool may include SL starting symbol information configured to be 0 and SL symbol length information configured to be 14. For example, a period of a physical sidelink feedback channel (PSFCH) resource within the second resource pool may be configured to be zero.
For example, a synchronization reference for the LTE SL communication and a synchronization reference for the NR SL communication may be the same.
The proposed method can be applied to the device(s) based on various embodiments of the present disclosure. First, the processor 202 of the second device 200 may control the transceiver 206 to receive, from a first device, based on a first sidelink (SL) resource, first sidelink control information (SCI) for scheduling of second SCI and a physical sidelink shared channel (PSSCH), through a physical sidelink control channel (PSCCH). In addition, the processor 202 of the second device 200 may control the transceiver 206 to receive, from the first device, based on the first SL resource, the second SCI and data, through the PSSCH. For example, the first SL resource selected within a second resource pool for NR SL communication may be a resource included in a slot that overlaps in time domain with a start of a first subframe within a first resource pool for long term evolution (LTE) SL communication.
Based on an embodiment of the present disclosure, a second device adapted to perform wireless communication may be provided. For example, the second device may comprise: one or more memories storing instructions; one or more transceivers; and one or more processors connected to the one or more memories and the one or more transceivers. For example, the one or more processors may execute the instructions to: control the one or more transceivers to receive, from a first device, based on a first sidelink (SL) resource, first sidelink control information (SCI) for scheduling of second SCI and a physical sidelink shared channel (PSSCH), through a physical sidelink control channel (PSCCH); and control the one or more transceivers to receive, from the first device, based on the first SL resource, the second SCI and data, through the PSSCH. For example, the first SL resource selected within a second resource pool for NR SL communication may be a resource included in a slot that overlaps in time domain with a start of a first subframe within a first resource pool for long term evolution (LTE) SL communication.
Based on an embodiment of the present disclosure, a processing device adapted to control a second device performing wireless communication may be provided. For example, the processing device may comprise: one or more processors; and one or more memories operably connected to the one or more processors and storing instructions. For example, the one or more processors may execute the instructions to: receive, from a first device, based on a first sidelink (SL) resource, first sidelink control information (SCI) for scheduling of second SCI and a physical sidelink shared channel (PSSCH), through a physical sidelink control channel (PSCCH); and receive, from the first device, based on the first SL resource, the second SCI and data, through the PSSCH. For example, the first SL resource selected within a second resource pool for NR SL communication may be a resource included in a slot that overlaps in time domain with a start of a first subframe within a first resource pool for long term evolution (LTE) SL communication.
Based on an embodiment of the present disclosure, a non-transitory computer-readable storage medium storing instructions may be provided. For example, the instructions, when executed, may cause a second device to: receive, from a first device, based on a first sidelink (SL) resource, first sidelink control information (SCI) for scheduling of second SCI and a physical sidelink shared channel (PSSCH), through a physical sidelink control channel (PSCCH); and receive, from the first device, based on the first SL resource, the second SCI and data, through the PSSCH. For example, the first SL resource selected within a second resource pool for NR SL communication may be a resource included in a slot that overlaps in time domain with a start of a first subframe within a first resource pool for long term evolution (LTE) SL communication.
Various embodiments of the present disclosure may be combined with each other.
Hereinafter, device(s) to which various embodiments of the present disclosure can be applied will be described.
The various descriptions, functions, procedures, proposals, methods, and/or operational flowcharts of the present disclosure described in this document may be applied to, without being limited to, a variety of fields requiring wireless communication/connection (e.g., 5G) between devices.
Hereinafter, a description will be given in more detail with reference to the drawings. In the following drawings/description, the same reference symbols may denote the same or corresponding hardware blocks, software blocks, or functional blocks unless described otherwise.
Referring to
Here, wireless communication technology implemented in wireless devices 100a to 100f of the present disclosure may include Narrowband Internet of Things for low-power communication in addition to LTE. NR, and 6G. In this case, for example, NB-IoT technology may be an example of Low Power Wide Area Network (LPWAN) technology and may be implemented as standards such as LTE Cat NB1, and/or LTE Cat NB2, and is not limited to the name described above. Additionally or alternatively, the wireless communication technology implemented in the wireless devices 100a to 100f of the present disclosure may perform communication based on LTE-M technology. In this case, as an example, the LTE-M technology may be an example of the LPWAN and may be called by various names including enhanced Machine Type Communication (eMTC), and the like. For example, the LTE-M technology may be implemented as at least any one of various standards such as 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. and is not limited to the name described above. Additionally or alternatively, the wireless communication technology implemented in the wireless devices 100a to 100f of the present disclosure may include at least one of Bluetooth, Low Power Wide Area Network (LPWAN), and ZigBee considering the low-power communication, and is not limited to the name described above. As an example, the ZigBee technology may generate personal area networks (PAN) related to small/low-power digital communication based on various standards including IEEE 802.15.4, and the like, and may be called by various names.
The wireless devices 100a to 100f may be connected to the network 300 via the BSs 200. An 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, 150b, or 150c may be established between the wireless devices 100a to 100f/BS 200, or BS 200/BS 200. Herein, the wireless communication/connections may be established through various RATs (e.g., 5G NR) such as uplink/downlink communication 150a, sidelink communication 150b (or, D2D communication), or inter BS communication (e.g. relay, Integrated Access Backhaul (IAB)). The wireless devices and the BSs/the wireless devices may transmit/receive radio signals to/from each other through the wireless communication/connections 150a and 150b. For example, the wireless communication/connections 150a and 150b may transmit/receive signals through various physical channels. 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.
Referring to
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 descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document. 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 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 store software code including commands for performing a part or the entirety of processes controlled by the processor(s) 102 or for performing the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document. Herein, 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 may be interchangeably used with Radio Frequency (RF) unit(s). In the present disclosure, the wireless device may represent a 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 descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document. 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 store software code including commands for performing a part or the entirety of processes controlled by the processor(s) 202 or for performing the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document. Herein, 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 may be interchangeably used with RF unit(s). In the present disclosure, the wireless device may represent a communication modem/circuit/chip.
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 PHY, MAC, RLC. PDCP. RRC, and SDAP). The one or more processors 102 and 202 may generate one or more Protocol Data Units (PDUs) and/or one or more Service Data Unit (SDUs) according to the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document. The one or more processors 102 and 202 may generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document. 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 descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document 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 descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document.
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 descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document 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 descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document 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 descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document 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, instructions, and/or commands. 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 this document, 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 descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document, 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 and 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 descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document, through the one or more antennas 108 and 208. In this document, 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.
Referring to
Codewords may be converted into radio signals via the signal processing circuit 1000 of
Specifically, the codewords may be converted into scrambled bit sequences by the scramblers 1010. Scramble sequences used for scrambling may be generated based on an initialization value, and the initialization value may include ID information of a wireless device. The scrambled bit sequences may be modulated to modulation symbol sequences by the modulators 1020. A modulation scheme may include pi/2-Binary Phase Shift Keying (pi/2-BPSK), m-Phase Shift Keying (m-PSK), and m-Quadrature Amplitude Modulation (m-QAM). Complex modulation symbol sequences may be mapped to one or more transport layers by the layer mapper 1030. Modulation symbols of each transport layer may be mapped (precoded) to corresponding antenna port(s) by the precoder 1040. Outputs z of the precoder 1040 may be obtained by multiplying outputs y of the layer mapper 1030 by an N*M precoding matrix W. Herein, N is the number of antenna ports and M is the number of transport layers. The precoder 1040 may perform precoding after performing transform precoding (e.g., DFT) for complex modulation symbols. Alternatively, the precoder 1040 may perform precoding without performing transform precoding.
The resource mappers 1050 may map modulation symbols of each antenna port to time-frequency resources. The time-frequency resources may include a plurality of symbols (e.g., a CP-OFDMA symbols and DFT-s-OFDMA symbols) in the time domain and a plurality of subcarriers in the frequency domain. The signal generators 1060 may generate radio signals from the mapped modulation symbols and the generated radio signals may be transmitted to other devices through each antenna. For this purpose, the signal generators 1060 may include Inverse Fast Fourier Transform (IFFT) modules, Cyclic Prefix (CP) inserters, Digital-to-Analog Converters (DACs), and frequency up-converters.
Signal processing procedures for a signal received in the wireless device may be configured in a reverse manner of the signal processing procedures 1010 to 1060 of
Referring to
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
In
Hereinafter, an example of implementing
Referring to
The communication unit 110 may transmit and receive signals (e.g., data and control signals) to and from other wireless devices or BSs. The control unit 120 may perform various operations by controlling constituent elements of the hand-held device 100. The control unit 120 may include an Application Processor (AP). The memory unit 130 may store data/parameters/programs/code/commands needed to drive the hand-held device 100. The memory unit 130 may store input/output data/information. The power supply unit 140a may supply power to the hand-held device 100 and include a wired/wireless charging circuit, a battery, etc. The interface unit 140b may support connection of the hand-held device 100 to other external devices. The interface unit 140b may include various ports (e.g., an audio I/O port and a video I/O port) for connection with external devices. The I/O unit 140c may input or output video information/signals, audio information/signals, data, and/or information input by a user. The I/O unit 140c may include a camera, a microphone, a user input unit, a display unit 140d, a speaker, and/or a haptic module.
As an example, in the case of data communication, the I/O unit 140c may acquire information/signals (e.g., touch, text, voice, images, or video) input by a user and the acquired information/signals may be stored in the memory unit 130. The communication unit 110 may convert the information/signals stored in the memory into radio signals and transmit the converted radio signals to other wireless devices directly or to a BS. The communication unit 110 may receive radio signals from other wireless devices or the BS and then restore the received radio signals into original information/signals. The restored information/signals may be stored in the memory unit 130 and may be output as various types (e.g., text, voice, images, video, or haptic) through the I/O unit 140c.
Referring to
The communication unit 110 may transmit and receive signals (e.g., data and control signals) to and from external devices such as other vehicles. BSs (e.g., gNBs and road side units), and servers. The control unit 120 may perform various operations by controlling elements of the vehicle or the autonomous vehicle 100. The control unit 120 may include an Electronic Control Unit (ECU) The driving unit 140a may cause the vehicle or the autonomous vehicle 100 to drive on a road. The driving unit 140a may include an engine, a motor, a powertrain, a wheel, a brake, a steering device, etc. The power supply unit 140b may supply power to the vehicle or the autonomous vehicle 100 and include a wired/wireless charging circuit, a battery, etc. The sensor unit 140c may acquire a vehicle state, ambient environment information, user information, etc. The sensor unit 140c may include an Inertial Measurement Unit (IMU) sensor, a collision sensor, a wheel sensor, a speed sensor, a slope sensor, a weight sensor, a heading sensor, a position module, a vehicle forward/backward sensor, a battery sensor, a fuel sensor, a tire sensor, a steering sensor, a temperature sensor, a humidity sensor, an ultrasonic sensor, an illumination sensor, a pedal position sensor, etc. The autonomous driving unit 140d may implement technology for maintaining a lane on which a vehicle is driving, technology for automatically adjusting speed, such as adaptive cruise control, technology for autonomously driving along a determined path, technology for driving by automatically setting a path if a destination is set, and the like.
For example, the communication unit 110 may receive map data, traffic information data, etc. from an external server. The autonomous driving unit 140d may generate an autonomous driving path and a driving plan from the obtained data. The control unit 120 may control the driving unit 140a such that the vehicle or the autonomous vehicle 100 may move along the autonomous driving path according to the driving plan (e.g., speed/direction control).
In the middle of autonomous driving, the communication unit 110 may aperiodically/periodically acquire recent traffic information data from the external server and acquire surrounding traffic information data from neighboring vehicles. In the middle of autonomous driving, the sensor unit 140c may obtain a vehicle state and/or surrounding environment information. The autonomous driving unit 140d may update the autonomous driving path and the driving plan based on the newly obtained data/information. The communication unit 110 may transfer information about a vehicle position, the autonomous driving path, and/or the driving plan to the external server. The external server may predict traffic information data using AI technology, etc., based on the information collected from vehicles or autonomous vehicles and provide the predicted traffic information data to the vehicles or the autonomous vehicles.
Claims in the present description can be combined in a various way. For instance, technical features in method claims of the present description can be combined to be implemented or performed in an apparatus, and technical features in apparatus claims can be combined to be implemented or performed in a method. Further, technical features in method claim(s) and apparatus claim(s) can be combined to be implemented or performed in an apparatus. Further, technical features in method claim(s) and apparatus claim(s) can be combined to be implemented or performed in a method.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2021-0078329 | Jun 2021 | KR | national |
| 10-2021-0078869 | Jun 2021 | KR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/KR2022/008467 | 6/15/2022 | WO |
