Patent Application
20250167924
The present disclosure relates to a wireless communication system, and more specifically to a method and device for performing uplink transmission and reception in a wireless communication system.
A mobile communication system has been developed to provide a voice service while guaranteeing mobility of users. However, a mobile communication system has extended even to a data service as well as a voice service, and currently, an explosive traffic increase has caused shortage of resources and users have demanded a faster service, so a more advanced mobile communication system has been required.
The requirements of a next-generation mobile communication system at large should be able to support accommodation of explosive data traffic, a remarkable increase in a transmission rate per user, accommodation of the significantly increased number of connected devices, very low End-to-End latency and high energy efficiency. To this end, a variety of technologies such as Dual Connectivity, Massive Multiple Input Multiple Output (Massive MIMO), In-band Full Duplex, Non-Orthogonal Multiple Access (NOMA), Super wideband Support, Device Networking, etc. have been researched.
The technical problem of the present disclosure is to provide a method and device for performing uplink transmission and reception in a wireless communication system.
In addition, an additional technical problem of the present disclosure is to provide a method and device for performing PUSCH repeated transmission based on the number of PRACH preamble repeated transmissions.
The technical objects to be achieved by the present disclosure are not limited to the above-described technical objects, and other technical objects which are not described herein will be clearly understood by those skilled in the pertinent art from the following description.
According to one embodiment of the present disclosure, A method of performing uplink transmission by a user equipment (UE) in a wireless communication system may include receiving, from a base station, first information related to repeated transmission of a physical random access channel (PRACH) preamble; performing repeated transmission of the PRACH preamble based on the first information; receiving, from the base station, a random access response (PAR) including a field related to repeated transmission of a physical uplink shared channel (PUSCH); and performing repeated transmission of the PUSCH based on the RAR, and a number of the repeated transmission of the PUSCH may be based on a number of the repeated transmission of the PRACH preamble.
According to one embodiment of the present disclosure, a method of performing uplink reception by a base station in a wireless communication system may include transmitting, to a user equipment (UE), first information related to repeated transmission of a physical random access channel (PRACH) preamble; performing repeated reception of the PRACH preamble based on the first information; transmitting, to the UE, a random access response (RAR) including a field related to repeated transmission of a physical uplink shared channel (PUSCH); and performing repeated reception of the PUSCH based on the RAR, and a number of the repeated transmission of the PUSCH may be based on a number of the repeated transmission of the PRACH preamble.
According to an embodiment of the present disclosure, a method and device for performing uplink transmission and reception in a wireless communication system may be provided.
In addition, according to various embodiments of the present disclosure, a method and apparatus for performing PUSCH repetition transmission based on the number of PRACH preamble repetition transmissions can be provided.
In addition, according to various embodiments of the present disclosure, since the number of PRACH preamble repetition transmissions is related to the number of PUSCH repetition transmissions, the base station can manage uplink resources more efficiently.
Effects achievable by the present disclosure are not limited to the above-described effects, and other effects which are not described herein may be clearly understood by those skilled in the pertinent art from the following description.
Accompanying drawings included as part of detailed description for understanding the present disclosure provide embodiments of the present disclosure and describe technical features of the present disclosure with detailed description.
Hereinafter, embodiments according to the present disclosure will be described in detail by referring to accompanying drawings. Detailed description to be disclosed with accompanying drawings is to describe exemplary embodiments of the present disclosure and is not to represent the only embodiment that the present disclosure may be implemented. The following detailed description includes specific details to provide complete understanding of the present disclosure. However, those skilled in the pertinent art knows that the present disclosure may be implemented without such specific details.
In some cases, known structures and devices may be omitted or may be shown in a form of a block diagram based on a core function of each structure and device in order to prevent a concept of the present disclosure from being ambiguous.
In the present disclosure, when an element is referred to as being “connected”, “combined” or “linked” to another element, it may include an indirect connection relation that yet another element presents therebetween as well as a direct connection relation. In addition, in the present disclosure, a term, “include” or “have”, specifies the presence of a mentioned feature, step, operation, component and/or element, but it does not exclude the presence or addition of one or more other features, stages, operations, components, elements and/or their groups.
In the present disclosure, a term such as “first”, “second”, etc. is used only to distinguish one element from other element and is not used to limit elements, and unless otherwise specified, it does not limit an order or importance, etc. between elements. Accordingly, within a scope of the present disclosure, a first element in an embodiment may be referred to as a second element in another embodiment and likewise, a second element in an embodiment may be referred to as a first element in another embodiment.
A term used in the present disclosure is to describe a specific embodiment, and is not to limit a claim. As used in a described and attached claim of an embodiment, a singular form is intended to include a plural form, unless the context clearly indicates otherwise. A term used in the present disclosure, “and/or”, may refer to one of related enumerated items or it means that it refers to and includes any and all possible combinations of two or more of them. In addition, “/” between words in the present disclosure has the same meaning as “and/or”, unless otherwise described.
The present disclosure describes a wireless communication network or a wireless communication system, and an operation performed in a wireless communication network may be performed in a process in which a device (e.g., a base station) controlling a corresponding wireless communication network controls a network and transmits or receives a signal, or may be performed in a process in which a terminal associated to a corresponding wireless network transmits or receives a signal with a network or between terminals.
In the present disclosure, transmitting or receiving a channel includes a meaning of transmitting or receiving information or a signal through a corresponding channel. For example, transmitting a control channel means that control information or a control signal is transmitted through a control channel. Similarly, transmitting a data channel means that data information or a data signal is transmitted through a data channel.
Hereinafter, a downlink (DL) means a communication from a base station to a terminal and an uplink (UL) means a communication from a terminal to a base station. In a downlink, a transmitter may be part of a base station and a receiver may be part of a terminal. In an uplink, a transmitter may be part of a terminal and a receiver may be part of a base station. A base station may be expressed as a first communication device and a terminal may be expressed as a second communication device. A base station (BS) may be substituted with a term such as a fixed station, a Node B, an eNB (evolved-NodeB), a gNB (Next Generation NodeB), a BTS (base transceiver system), an Access Point (AP), a Network (5G network), an AI (Artificial Intelligence) system/module, an RSU (road side unit), a robot, a drone (UAV: Unmanned Aerial Vehicle), an AR (Augmented Reality) device, a VR (Virtual Reality) device, etc. In addition, a terminal may be fixed or mobile, and may be substituted with a term such as a UE (User Equipment), an MS (Mobile Station), a UT (user terminal), an MSS (Mobile Subscriber Station), an SS (Subscriber Station), an AMS (Advanced Mobile Station), a WT (Wireless terminal), an MTC (Machine-Type Communication) device, an M2M (Machine-to-Machine) device, a D2D (Device-to-Device) device, a vehicle, an RSU (road side unit), a robot, an AI (Artificial Intelligence) module, a drone (UAV: Unmanned Aerial Vehicle), an AR (Augmented Reality) device, a VR (Virtual Reality) device, etc.
The following description may be used for a variety of radio access systems such as CDMA, FDMA, TDMA, OFDMA, SC-FDMA, etc. CDMA may be implemented by a wireless technology such as UTRA (Universal Terrestrial Radio Access) or CDMA2000. TDMA may be implemented by a radio technology such as GSM (Global System for Mobile communications)/GPRS (General Packet Radio Service)/EDGE (Enhanced Data Rates for GSM Evolution). OFDMA may be implemented by a radio technology such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, E-UTRA (Evolved UTRA), etc. UTRA is a part of a UMTS (Universal Mobile Telecommunications System). 3GPP (3rd Generation Partnership Project) LTE (Long Term Evolution) is a part of an E-UMTS (Evolved UMTS) using E-UTRA and LTE-A (Advanced)/LTE-A pro is an advanced version of 3GPP LTE. 3GPP NR (New Radio or New Radio Access Technology) is an advanced version of 3GPP LTE/LTE-A/LTE-A pro.
To clarify description, it is described based on a 3GPP communication system (e.g., LTE-A, NR), but a technical idea of the present disclosure is not limited thereto. LTE means a technology after 3GPP TS (Technical Specification) 36.xxx Release 8. In detail, an LTE technology in or after 3GPP TS 36.xxx Release 10 is referred to as LTE-A and an LTE technology in or after 3GPP TS 36.xxx Release 13 is referred to as LTE-A pro. 3GPP NR means a technology in or after TS 38.xxx Release 15. LTE/NR may be referred to as a 3GPP system. “xxx” means a detailed number for a standard document. LTE/NR may be commonly referred to as a 3GPP system. For a background art, a term, an abbreviation, etc. used to describe the present disclosure, matters described in a standard document disclosed before the present disclosure may be referred to. For example, the following document may be referred to.
For 3GPP LTE, TS 36.211 (physical channels and modulation), TS 36.212 (multiplexing and channel coding), TS 36.213 (physical layer procedures), TS 36.300 (overall description), TS 36.331 (radio resource control) may be referred to.
For 3GPP NR, TS 38.211 (physical channels and modulation), TS 38.212 (multiplexing and channel coding), TS 38.213 (physical layer procedures for control), TS 38.214 (physical layer procedures for data), TS 38.300 (NR and NG-RAN (New Generation-Radio Access Network) overall description), TS 38.331 (radio resource control protocol specification) may be referred to.
Abbreviations of terms which may be used in the present disclosure is defined as follows.
As more communication devices have required a higher capacity, a need for an improved mobile broadband communication compared to the existing radio access technology (RAT) has emerged. In addition, massive MTC (Machine Type Communications) providing a variety of services anytime and anywhere by connecting a plurality of devices and things is also one of main issues which will be considered in a next-generation communication. Furthermore, a communication system design considering a service/a terminal sensitive to reliability and latency is also discussed. As such, introduction of a next-generation RAT considering eMBB (enhanced mobile broadband communication), mMTC (massive MTC), URLLC (Ultra-Reliable and Low Latency Communication), etc. is discussed and, for convenience, a corresponding technology is referred to as NR in the present disclosure. NR is an expression which represents an example of a 5G RAT.
A new RAT system including NR uses an OFDM transmission method or a transmission method similar to it. A new RAT system may follow OFDM parameters different from OFDM parameters of LTE. Alternatively, a new RAT system follows a numerology of the existing LTE/LTE-A as it is, but may support a wider system bandwidth (e.g., 100 MHz). Alternatively, one cell may support a plurality of numerologies. In other words, terminals which operate in accordance with different numerologies may coexist in one cell.
A numerology corresponds to one subcarrier spacing in a frequency domain. As a reference subcarrier spacing is scaled by an integer N, a different numerology may be defined.
In reference to
A NR system may support a plurality of numerologies. Here, a numerology may be defined by a subcarrier spacing and a cyclic prefix (CP) overhead. Here, a plurality of subcarrier spacings may be derived by scaling a basic (reference) subcarrier spacing by an integer N (or, μ). In addition, although it is assumed that a very low subcarrier spacing is not used in a very high carrier frequency, a used numerology may be selected independently from a frequency band. In addition, a variety of frame structures according to a plurality of numerologies may be supported in a NR system.
Hereinafter, an OFDM numerology and frame structure which may be considered in a NR system will be described. A plurality of OFDM numerologies supported in a NR system may be defined as in the following Table 1.
NR supports a plurality of numerologies (or subcarrier spacings (SCS)) for supporting a variety of 5G services. For example, when a SCS is 15 kHz, a wide area in traditional cellular bands is supported, and when a SCS is 30 kHz/60 kHz, dense-urban, lower latency and a wider carrier bandwidth are supported, and when a SCS is 60 kHz or higher, a bandwidth wider than 24.25 GHz is supported to overcome a phase noise. An NR frequency band is defined as a frequency range in two types (FR1, FR2). FR1, FR2 may be configured as in the following Table 2. In addition, FR2 may mean a millimeter wave (mmW).
Regarding a frame structure in an NR system, a size of a variety of fields in a time domain is expresses as a multiple of a time unit of Tc=1/(Δfmax·Nf). Here, Δfmax is 480-103 Hz and Nf is 4096. Downlink and uplink transmission is configured (organized) with a radio frame having a duration of Tf=1/(ΔfmaxNf/100)·Tc=10 ms. Here, a radio frame is configured with 10 subframes having a duration of Tsf=(ΔfmaxNf/1000) Tc=1 ms, respectively. In this case, there may be one set of frames for an uplink and one set of frames for a downlink. In addition, transmission in an uplink frame No. i from a terminal should start earlier by TTA=(NTA+NTA,offset)Tc than a corresponding downlink frame in a corresponding terminal starts. For a subcarrier spacing configuration μ, slots are numbered in an increasing order of nsμ∈{0, . . . , Nslotsubframe,μ−1} in a subframe and are numbered in an increasing order of ns,fμ∈{0, . . . , Nslotframe,μ−1} in a radio frame. One slot is configured with Nsymbslot consecutive OFDM symbols and Nsymbslot is determined according to CP. A start of a slot nsμ in a subframe is temporally arranged with a start of an OFDM symbol nsμNsymbslot in the same subframe. All terminals may not perform transmission and reception at the same time, which means that all OFDM symbols of a downlink slot or an uplink slot may not be used.
Table 3 represents the number of OFDM symbols per slot (Nsymbslot), the number of slots per radio frame (Nslotframe,μ) and the number of slots per subframe (Nslotsubframe,μ) in a normal CP and Table 4 represents the number of OFDM symbols per slot, the number of slots per radio frame and the number of slots per subframe in an extended CP.
Hereinafter, the physical resources which may be considered in an NR system will be described in detail. First, in relation to an antenna port, an antenna port is defined so that a channel where a symbol in an antenna port is carried can be inferred from a channel where other symbol in the same antenna port is carried. When a large-scale property of a channel where a symbol in one antenna port is carried may be inferred from a channel where a symbol in other antenna port is carried, it may be said that 2 antenna ports are in a QC/QCL (quasi co-located or quasi co-location) relationship.
In this case, the large-scale property includes at least one of delay spread, doppler spread, frequency shift, average received power, received timing.
In reference to
Point A plays a role as a common reference point of a resource block grid and is obtained as follows.
offsetToPointA for a primary cell (PCell) downlink represents a frequency offset between point A and the lowest subcarrier of the lowest resource block overlapped with a SS/PBCH block which is used by a terminal for an initial cell selection. It is expressed in resource block units assuming a 15 kHz subcarrier spacing for FR1 and a 60 kHz subcarrier spacing for FR2.
absoluteFrequencyPointA represents a frequency-position of point A expressed as in ARFCN (absolute radio-frequency channel number). Common resource blocks are numbered from 0 to the top in a frequency domain for a subcarrier spacing configuration μ. The center of subcarrier 0 of common resource block 0 for a subcarrier spacing configuration μ is identical to ‘point A’. A relationship between a common resource block number nCRBμ and a resource element (k,l) for a subcarrier spacing configuration μ in a frequency domain is given as in the following Equation 1.
In Equation 1, k is defined relatively to point A so that k=0 corresponds to a subcarrier centering in point A. Physical resource blocks are numbered from 0 to NBWP,isize,μ−1 in a bandwidth part (BWP) and i is a number of a BWP. A relationship between a physical resource block nPRB and a common resource block nCRB in BWP i is given by the following Equation 2.
NBWP,istart,μ is a common resource block that a BWP starts relatively to common resource block 0.
In reference to
A carrier includes a plurality of subcarriers in a frequency domain. An RB (Resource Block) is defined as a plurality of (e.g., 12) consecutive subcarriers in a frequency domain. A BWP (Bandwidth Part) is defined as a plurality of consecutive (physical) resource blocks in a frequency domain and may correspond to one numerology (e.g., an SCS, a CP length, etc.). A carrier may include a maximum N (e.g., 5) BWPs. A data communication may be performed through an activated BWP and only one BWP may be activated for one terminal. In a resource grid, each element is referred to as a resource element (RE) and one complex symbol may be mapped.
In an NR system, up to 400 MHz may be supported per component carrier (CC). If a terminal operating in such a wideband CC always operates turning on a radio frequency (FR) chip for the whole CC, terminal battery consumption may increase. Alternatively, when several application cases operating in one wideband CC (e.g., eMBB, URLLC, Mmtc, V2X, etc.) are considered, a different numerology (e.g., a subcarrier spacing, etc.) may be supported per frequency band in a corresponding CC. Alternatively, each terminal may have a different capability for the maximum bandwidth. By considering it, a base station may indicate a terminal to operate only in a partial bandwidth, not in a full bandwidth of a wideband CC, and a corresponding partial bandwidth is defined as a bandwidth part (BWP) for convenience. A BWP may be configured with consecutive RBs on a frequency axis and may correspond to one numerology (e.g., a subcarrier spacing, a CP length, a slot/a mini-slot duration).
Meanwhile, a base station may configure a plurality of BWPs even in one CC configured to a terminal. For example, a BWP occupying a relatively small frequency domain may be configured in a PDCCH monitoring slot, and a PDSCH indicated by a PDCCH may be scheduled in a greater BWP. Alternatively, when UEs are congested in a specific BWP, some terminals may be configured with other BWP for load balancing. Alternatively, considering frequency domain inter-cell interference cancellation between neighboring cells, etc., some middle spectrums of a full bandwidth may be excluded and BWPs on both edges may be configured in the same slot.
In other words, a base station may configure at least one DL/UL BWP to a terminal associated with a wideband CC. A base station may activate at least one DL/UL BWP of configured DL/UL BWP(s) at a specific time (by L1 signaling or MAC CE (Control Element) or RRC signaling, etc.). In addition, a base station may indicate switching to other configured DL/UL BWP (by L1 signaling or MAC CE or RRC signaling, etc.). Alternatively, based on a timer, when a timer value is expired, it may be switched to a determined DL/UL BWP. Here, an activated DL/UL BWP is defined as an active DL/UL BWP. But, a configuration on a DL/UL BWP may not be received when a terminal performs an initial access procedure or before a RRC connection is set up, so a DL/UL BWP which is assumed by a terminal under these situations is defined as an initial active DL/UL BWP.
In a wireless communication system, a terminal receives information through a downlink from a base station and transmits information through an uplink to a base station. Information transmitted and received by a base station and a terminal includes data and a variety of control information and a variety of physical channels exist according to a type/a usage of information transmitted and received by them.
When a terminal is turned on or newly enters a cell, it performs an initial cell search including synchronization with a base station or the like (S601). For the initial cell search, a terminal may synchronize with a base station by receiving a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) from a base station and obtain information such as a cell identifier (ID), etc. After that, a terminal may obtain broadcasting information in a cell by receiving a physical broadcast channel (PBCH) from a base station. Meanwhile, a terminal may check out a downlink channel state by receiving a downlink reference signal (DL RS) at an initial cell search stage.
A terminal which completed an initial cell search may obtain more detailed system information by receiving a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) according to information carried in the PDCCH (S602).
Meanwhile, when a terminal accesses to a base station for the first time or does not have a radio resource for signal transmission, it may perform a random access (RACH) procedure to a base station (S603 to S606). For the random access procedure, a terminal may transmit a specific sequence as a preamble through a physical random access channel (PRACH) (S603 and S605) and may receive a response message for a preamble through a PDCCH and a corresponding PDSCH (S604 and S606). A contention based RACH may additionally perform a contention resolution procedure.
A terminal which performed the above-described procedure subsequently may perform PDCCH/PDSCH reception (S607) and PUSCH (Physical Uplink Shared Channel)/PUCCH (physical uplink control channel) transmission (S608) as a general uplink/downlink signal transmission procedure. In particular, a terminal receives downlink control information (DCI) through a PDCCH. Here, DCI includes control information such as resource allocation information for a terminal and a format varies depending on its purpose of use.
Meanwhile, control information which is transmitted by a terminal to a base station through an uplink or is received by a terminal from a base station includes a downlink/uplink ACK/NACK (Acknowledgement/Non-Acknowledgement) signal, a CQI (Channel Quality Indicator), a PMI (Precoding Matrix Indicator), a RI (Rank Indicator), etc. For a 3GPP LTE system, a terminal may transmit control information of the above-described CQI/PMI/RI, etc. through a PUSCH and/or a PUCCH.
Table 5 represents an example of a DCI format in an NR system.
In reference to Table 5, DCI formats 0_0, 0_1 and 0_2 may include resource information (e.g., UL/SUL (Supplementary UL), frequency resource allocation, time resource allocation, frequency hopping, etc.), information related to a transport block (TB) (e.g., MCS (Modulation Coding and Scheme), a NDI (New Data Indicator), a RV (Redundancy Version), etc.), information related to a HARQ (Hybrid—Automatic Repeat and request) (e.g., a process number, a DAI (Downlink Assignment Index), PDSCH-HARQ feedback timing, etc.), information related to multiple antennas (e.g., DMRS sequence initialization information, an antenna port, a CSI request, etc.), power control information (e.g., PUSCH power control, etc.) related to scheduling of a PUSCH and control information included in each DCI format may be pre-defined.
DCI format 0_0 is used for scheduling of a PUSCH in one cell. Information included in DCI format 0_0 is CRC (cyclic redundancy check) scrambled by a C-RNTI (Cell Radio Network Temporary Identifier) or a CS-RNTI (Configured Scheduling RNTI) or a MCS-C-RNTI (Modulation Coding Scheme Cell RNTI) and transmitted.
DCI format 0_1 is used to indicate scheduling of one or more PUSCHs or configure grant (CG) downlink feedback information to a terminal in one cell. Information included in DCI format 0_1 is CRC scrambled by a C-RNTI or a CS-RNTI or a SP-CSI-RNTI (Semi-Persistent CSI RNTI) or a MCS-C-RNTI and transmitted.
DCI format 0_2 is used for scheduling of a PUSCH in one cell. Information included in DCI format 0_2 is CRC scrambled by a C-RNTI or a CS-RNTI or a SP-CSI-RNTI or a MCS-C-RNTI and transmitted.
Next, DCI formats 1_0, 11 and 1_2 may include resource information (e.g., frequency resource allocation, time resource allocation, VRB (virtual resource block)-PRB (physical resource block) mapping, etc.), information related to a transport block (TB) (e.g., MCS, NDI, RV, etc.), information related to a HARQ (e.g., a process number, DAI, PDSCH-HARQ feedback timing, etc.), information related to multiple antennas (e.g., an antenna port, a TCI (transmission configuration indicator), a SRS (sounding reference signal) request, etc.), information related to a PUCCH (e.g., PUCCH power control, a PUCCH resource indicator, etc.) related to scheduling of a PDSCH and control information included in each DCI format may be pre-defined.
DCI format 1_0 is used for scheduling of a PDSCH in one DL cell. Information included in DCI format 1_0 is CRC scrambled by a C-RNTI or a CS-RNTI or a MCS-C-RNTI and transmitted.
DCI format 1_1 is used for scheduling of a PDSCH in one cell. Information included in DCI format 1_1 is CRC scrambled by a C-RNTI or a CS-RNTI or a MCS-C-RNTI and transmitted.
DCI format 1_2 is used for scheduling of a PDSCH in one cell. Information included in DCI format 1_2 is CRC scrambled by a C-RNTI or a CS-RNTI or a MCS-C-RNTI and transmitted.
In the following description, a cell operating in a licensed-band (L-band) is defined as an LCell, and a carrier of the LCell is defined as a (downlink/uplink) LCC. In addition, a cell operating in an unlicensed band (U-band) is defined as a UCell, and a carrier of the UCell is defined as a (downlink/uplink) UCC. The carrier/carrier-frequency of a cell may mean an operating frequency (e.g., center frequency) of the cell. A cell/carrier (e.g., a component carrier (CC)) is collectively referred to as a cell.
As shown in (a) of
For example, the unlicensed band may be included in a specific frequency range (e.g., from 52.6 GHz to 71 GHz) higher than the existing frequency range (e.g., FR1 and FR2). The specific frequency range may be referred to as FR2-2 (in this case, the existing FR2 (i.e., 24250 MHz-52600 MHz) may be referred to as FR2-1) or may be referred to as FR3. The scope of this disclosure is not limited to the designations FR2-2 or FR3.
Referring to
A UE receives DCI for uplink scheduling (i.e., including scheduling information of a PUSCH) from a base station on a PDCCH (S1502).
DCI format 0_0, 0_1, or 0_2 may be used for uplink scheduling, and in particular, DCI format 0_1 includes the following information: an identifier for a DCI format, a UL/SUL (supplementary uplink) indicator, a bandwidth part indicator, a frequency domain resource assignment, a time domain resource assignment, a frequency hopping flag, a modulation and coding scheme (MCS), an SRS resource indicator (SRI), precoding information and number of layers, antenna port(s), an SRS request, a DMRS sequence initialization, a UL-SCH (Uplink Shared Channel) indicator
In particular, SRS resources configured in an SRS resource set associated with the higher upper layer parameter ‘usage’ may be indicated by an SRS resource indicator field. Additionally, the ‘spatialRelationInfo’ can be configured for each SRS resource, and its value can be one of {CRI, SSB, SRI}.
A UE transmits uplink data to a base station on a PUSCH (S1503).
When a UE detects a PDCCH including DCI formats 0_0, 0_1, and 0_2, it transmits a PUSCH according to indications by corresponding DCI.
Two transmission methods are supported for PUSCH transmission: codebook-based transmission and non-codebook-based transmission:
For codebook-based transmission, a PUSCH may be scheduled in DCI format 0_0, DCI format 0_1, DCI format 0_2, or semi-statically. If this PUSCH is scheduled by DCI format 0_1, a UE determines a PUSCH transmission precoder based on an SRI, a TPMI (Transmit Precoding Matrix Indicator), and a transmission rank from DCI, as given by an SRS resource indicator field and a precoding information and number of layers field. A TPMI is used to indicate a precoder to be applied across antenna ports, and corresponds to an SRS resource selected by an SRI when multiple SRS resources are configured.
Alternatively, if a single SRS resource is configured, a TPMI is used to indicate a precoder to be applied across antenna ports and corresponds to that single SRS resource. A transmission precoder is selected from an uplink codebook having the same number of antenna ports as the higher layer parameter ‘nrofSRS-Ports’. When a UE is configured with the higher layer parameter ‘txConfig’ set to ‘codebook’, the UE is configured with at least one SRS resource. An SRI indicated in slot n is associated with the most recent transmission of an SRS resource identified by the SRI, where the SRS resource precedes a PDCCH carrying the SRI (i.e., slot n).
A UE uses one or multiple SRS resources for SRS transmission, where the number of SRS resources can be configured for simultaneous transmission within the same RB based on a UE capability. Only one SRS port is configured for each SRS resource. Only one SRS resource can be configured with the higher layer parameter ‘usage’ set to ‘nonCodebook’. The maximum number of SRS resources that can be configured for non-codebook based uplink transmission is 4. An SRI indicated in slot n is associated with the most recent transmission of an SRS resource identified by the SRI, where the SRS transmission precedes a PDCCH carrying the SRI (i.e., slot n).
In order to improve UL coverage of a basic wireless communication system, a PRACH preamble repetition transmission operation may be performed. Hereinafter, a method for a terminal to enable PRACH preamble repetition transmission (or/and Msg. 3 PUSCH repetition transmission) according to an embodiment of the present disclosure will be described in detail.
Here, in the 4-step RACH procedure, Msg. 1 (message 1) may include a preamble (i.e., a PRACH preamble). Msg. 2 may include a random access response (RAR) corresponding to Msg 1. Msg. 3 may include a PUSCH based on uplink resource allocation information provided by the PAR.
The present disclosure may be applied in combination with the above-described contents (e.g., NR frame structure, RACH procedure, U-band system, etc.). In addition, the methods related to configuring PRACH transmission occasions to be described later may be equally applied to an uplink signal transmission and reception method.
For example, uplink transmission through methods related to PRACH transmission opportunity configuration described later can be performed in an L-cell and/or U-cell defined in an NR system or a U-Band system.
The UE may receive first information related to repeated transmission of a physical random access channel (PRACH) preamble from the base station (S910).
For example, the first information may include the number of repeated transmission of a PRACH preamble, etc. Here, the first information may include a number (candidates) of repeated transmission of a plurality of PRACH preambles. The number (candidates) of repeated transmission of a plurality of PRACH preamble may be configured as one set.
And, the UE may receive first information from the base station through RRC (radio resource control) signaling (or/and SIB) related to PRACH transmission. The RRC signaling related to PRACH transmission may include resource allocation information for repeated transmission of PRACH preamble.
Before or after S910, the UE may transmit second information (e.g., UE capability information) supporting repeated transmission of a PRACH preamble to the base station. Accordingly, the UE may notify the base station that it supports repeated transmission of a PRACH preamble.
The UE may implicitly inform the base station that it supports repeated transmission of a PUSCH by transmitting second information (e.g., UE capability information) supporting repeated transmission of the PRACH preamble to the base station.
The UE may perform repeated transmission of the PRACH preamble based on the first information (S920). That is, the UE may perform repetition transmission of the PRACH preamble based on RRC signaling related to PRACH transmission and/or the first information.
For example, the UE may perform repeated transmission of the PRACH preamble as many times as the number of repeated transmissions of the PRACH preamble included in the first information.
The UE may receive a random access response (EAR) including a field related to repeated transmission of a physical uplink shared channel (PUSCH) from the base station (S930).
For example, fields related to repeated transmission may include a repetition number field indicating the number of repeated transmission of a PRACH preamble.
Additionally or alternatively, RAR may include a field for indicating whether to repeat PUSCH preamble transmission (e.g., dynamic indication field), frequency/time resource allocation field for PUSCH transmission, etc.
In addition, all or part of the resources allocated for PUSCH repeated transmission may be allocated for PRACH preamble repeated transmission.
The UE may perform repeated transmission of the PUSCH based on RAR (S940).
Here, the number of repeated transmission of the PUSCH may be based on the number of repeated transmission of the PRACH preamble.
For example, a set of candidate values for the number of the repeated transmission of the PUSCH (i.e., a set of values that can be the number of PUSCH repetition transmissions) may be configured based on the number of repeated transmission of the PRACH preamble.
As another example, the number of the repeated transmission of the PUSCH may be a value indicated by a field related to the repeated transmission of the PUSCH among the number of the repeated transmission of the plurality of PRACH preambles.
As another example, the set of candidate values of the number of PUSCH repetition transmissions may be configured to a set of default numbers corresponding to the number of PRACH preamble repetition transmissions. For example, based on the number of repeated transmission of the PRACH preamble being N, the number of repeated transmission of the PRACH preamble may be configured to {a, b, c, d}. In this case, based on the number of the repeated transmission of the PRACH preamble being 2N, the set of the number of the repeated transmission of the PRACH preamble may be configured to {2a, 2b, 2c, 2d}.
The base station may transmit first information related to repeated transmission of a PRACH preamble to the UE (S1010).
For example, a base station may receive capability information indicating that the UE supports PRACH preamble repetition transmission. The base station may determine that the UE supports PUSCH repetition transmission through the capability information.
The base station may transmit first information including the number of times a PRACH preamble is repeated to the UE via higher layer signaling (e.g., RRC signaling or/and SIB1).
The base station may perform repeated reception of the PRACH preamble based on the first information (S1020).
The base station may transmit a random access response (PAR) including a field related to repeated transmission of a physical uplink shared channel (PUSCH) to the UE (S1030).
The base station may perform repeated reception of the PUSCH based on RAR (S1040).
The operations and parameters related to S1010, S1020, S1030, and S1040 may correspond to the operations and parameters related to S910, S920, S930, and S940, so redundant descriptions are omitted.
Hereinafter, a PRACH repetition transmission method for improving coverage of a wireless communication system is specifically described.
Embodiment 1 relates to a method for configuring PRACH repeated transmission for a UE and a method for the UE to perform PRACH repeated transmission.
In a basic wireless communication system, the PRACH preamble transmission method includes a method of transmitting a PRACH preamble once at a specific time to a RO (RACH occasion) selected by a UE among the ROs determined by the PRACH configuration configured by the base station and the SSB-to-RO mapping rule.
Here, if a specific terminal is far from the cell center or is in a place with poor signal strength, the initial access procedure cannot help but be long with only one preamble transmission. Accordingly, the PRACH preamble repetition transmission method can be applied.
First, in order to inform the UE of the number of PRACH preamble repetitions, the base station may transmit the (PRACH) repetition number (or RO bundling number) to the UE cell-specifically (or cell common) through the higher layer signaling (e.g., SIB1, other SIB, or RRC signaling, etc.), etc.
Specifically, the number of repetitions may be configured/indicated to the UE together with the higher layer signaling related to RACH configuration (or, in the same signal/channel). Here, the number of repetitions may be configured as a positive integer. For example, the number of repetitions may be configured in the form of an exponent of 2 (e.g., 20 or 21 or 2N, etc.).
Additionally, the number of repetitions may configure/indicate the total number of times the UE should repeatedly transmit the PRACH preamble.
Additionally or alternatively, the repetition number may configure/indicate the total number of ROs that the UE should select to repeatedly transmit the PRACH preamble.
Additionally or alternatively, the repetition number may be configured to only one per RACH configuration (or per BWP/cell/carrier), but is not limited thereto. The repetition number may be configured to two or more repetition numbers per RACH configuration (or per BWP/cell/carrier).
Additionally, the base station may configure/indicate the UE to allocate resources for repeated transmission of PRACH preambles (or, on the same signal/channel) in addition to the higher layer signaling related to RACH configuration.
For example, the resource may include a specific RO, or a specific RAPID (Random access preamble ID) of each RO (e.g., a RO allocated to a specific (even or odd index) RACH slot, or an even or slot odd index RO of each RACH slot) (e.g., set to a starting RAPID+total number of RAPIDs), etc. Additionally, the base station may configure/indicate the UE to allocate resources for each of one or more repetition numbers in a similar manner as described above.
Additionally, the UE may receive the above information (e.g., repetition number, RACH related configuration information and/or resources allocated for repeated transmission of PRACH preamble, etc.) from the base station through higher layer signaling.
Here, if a specific condition that is preconfigured/defined/indicated is not satisfied, the UE may be configured/indicated/defined not to perform PRACH preamble repetition transmission, but to perform the RACH procedure of the basic wireless communication system. On the other hand, if a specific condition is satisfied, the UE may be configured/instructed/defined to perform PRACH preamble repetition transmission. In addition, the specific condition may be subdivided, and the UE may select one of a plurality of repetition numbers.
For example, the specific criterion may include a criterion related to the RSRP (Reference Signals Received Power) value of the UE.
Specifically, if the total number of repetitions that the UE can select is A, including cases where PRACH repeat transmission is not performed (e.g., when the repetition number is 1), the base station may configure/indicate A-1 RSRP thresholds to the UE through the higher layer signaling (together with RACH configuration). Here, the UE may be configured/indicated/defined to select an appropriate repetition number based on multiple RSRP thresholds indicated by the base station and the RSRP value of the UE.
Additionally, the RSRP threshold, which is the criterion for selecting the repetition level/number of times, may be preset to be associated with a parameter (e.g., ‘RSRP-ThresholdSSBlock’) that is the criterion for selecting the SSB index. When RSRP-ThresholdSSBlock is configured for a UE, the UE may select an SSB and the corresponding PRACH resource for path loss estimation and (re)transmission based on an SSB that satisfies the threshold.
For example, the base station may set A-1 RSRP-ThresholdSSBlock associated with each of the A-1 repetition selection thresholds for the UE. Thereafter, the UE may select a repetition number X corresponding thereto based on the repetition threshold interval. The UE may be configured/indicated/defined to perform X repetition transmissions by selecting ROs linked to the selected SSB index based on the RSRP-ThresholdSSBlock set for the selected repetition number X.
Here, a condition for the UE to select the repetition number may be preset. As an example of the condition, if at least one SSB index corresponds (satisfies) to a specific repetition threshold interval, the UE may be configured to select the repetition number corresponding to the repetition threshold interval. And, considering beam diversity, if at least M (Here, M may be predefined or may be indicated by the base station through the higher layer signaling) or more SSB indexes correspond to a specific repetition threshold interval, the UE may be configured to select the repetition number corresponding to the repetition threshold interval.
Additionally or alternatively, RSRP-ThresholdSSBlock may be configured for the UE only when the PRACH preamble is not repeatedly transmitted (i.e., only when the number of PRACH preamble repetitions=1). And, the UE may be configured to select both the number of repetitions and the SSB index using only the A-1 repetition selection thresholds.
For example, assume that at least one SSB index corresponds to (or satisfies) a specific repetition number interval. If a repetition number X corresponding to the repetition threshold interval is selected, the UE may be configured to perform X repetition transmissions by selecting one SSB index based on the (same) repetition threshold interval and thereby selecting ROs linked with the SSB index.
The UE may be configured to perform a PRACH preamble repetition transmission operation based on a selected repetition number until the RACH procedure being performed is completed or the UL sync access fails.
As another example of the present disclosure, assume that the base station does not indicate the UE to repeat a number of times greater than 1, or that the base station does not provide the UE with resource allocation information for PRACH preamble repetition. In this case, the UE may determine that the base station does not allow PRACH preamble repetition transmission in the corresponding PRACH configuration, and may be configured to perform a RACH procedure of a basic wireless communication system.
In one embodiment of the present disclosure, the UE may be configured to select a best SSB index among the measured SSB indices, and compare the SSB index and an RSRP threshold value to select a repetition number.
That is, if the best SSB index (or RSRP of the SSB) selected by the UE is included in a specific repetition threshold interval, the UE may select the number of repetitions associated with the interval and perform PRACH preamble repetition transmission using the ROs mapped to the SSB index.
A parameter/UE characteristic indicating whether Msg. 3 PUSCH is repeatedly transmitted may be defined. To this end, the base station may indicate an RSRP threshold for Msg. 3 PUSCH repeated transmission to the UE. The UE may determine whether to request Msg. 3 PUSCH repeated transmission to the base station based on the RSRP threshold.
Additionally or alternatively, if a parameter/UE characteristic indicating whether to repeat PRACH preamble transmission is defined, the base station may indicate to the UE an RSRP threshold for repeated PRACH preamble transmission.
For example, the base station may provide/configure an RSRP threshold for PRACH preamble repetition transmission independently of the RSRP threshold for Msg. 3 PUSCH repetition transmission to the UE through the higher layer signaling.
For example, assume that the RSRP threshold for PRACH preamble repetition transmission is configured for the UE (and/or, if the base station indicates the UE to a value other than 1 as the number of PRACH preamble repetitions) and the base station does not separately indicate the UE to the RSRP threshold for PRACH preamble repetition transmission (i.e., if the base station does not provide the UE with a parameter indicating the RSRP threshold for PRACH preamble repetition transmission through the higher layer signaling).
Here, the UE may be configured to reuse the RSRP threshold for repeated transmission of Msg. 3 PUSCH as the RSRP threshold for repeated transmission of PRACH preamble. That is, the UE may interpret that the RSRP threshold for repeated transmission of PRACH preamble and the RSRP threshold for repeated transmission of Msg. 3 PUSCH are the same.
As another example of the present disclosure, the UE may be configured to use the same value as the RSRP threshold for the conventional Msg. 3 PUSCH repeated transmission as the RSRP threshold for the PRACH preamble repeated transmission. That is, the RSRP threshold for the PRACH preamble repeated transmission may not be separately configured for the UE.
Accordingly, no new parameters for similar operations may be added, and the UE may determine whether to repeat transmission of the PRACH preamble and/or Msg. 3 PUSCH through the common RSRP threshold. Accordingly, signaling overhead and UE implementation complexity may be reduced.
For repeated transmission of Msg. A (PRACH preamble and PUSCH) in 2-step RACH, the base station may configure/indicate the UE the number of repetitions using the method described below.
For example, if the base station configures/indicates the UE to repeat N times, the repetition number N may be defined/applied to the Msg. A preamble transmission. When selecting N ROs through a pre-agreed operation, the UE may not consider whether there is a Msg. A PUSCH resource paired to each RO. Accordingly, the Msg. A preamble may be repeatedly transmitted N times (assuming there is no RO dropping), and the Msg. A PUSCH may be repeatedly transmitted a number of times less than or equal to N.
As another example, if the base station configures/indicates the repetition number N to the UE, the repetition number N may be defined/applied to the Msg. A preamble and the Msg. A PUSCH (i.e., the Msg. A preamble is transmitted N times and the Msg. A PUSCH is also transmitted N times). Accordingly, when selecting N ROs through a pre-agreed operation, the UE may select only the ROs in which the Msg. A PUSCH resources paired to each RO exist.
As another example, the base station may configure/indicate to transmit the Msg. A preamble repeatedly N times and the Msg. A PUSCH repeatedly M times using independent parameters. Accordingly, when selecting N ROs through a pre-agreed operation, the UE may select the ROs such that there are at least M Msg. A PUSCH resources paired to each RO.
Embodiment 2 relates to a method for repeating transmission of Msg. 3 PUSCH according to PRACH repetition configurations.
The base station may configure/indicate the UE parameters and/or resources for PRACH preamble repetition transmission through the higher layer signaling, and additionally, the base station may configure/indicate the UE parameters and/or resources for Msg. 3 PUSCH repetition transmission through the higher layer signaling.
Here, if the UE performs a PRACH preamble repeat transmission operation, the UE may be configured to expect that the Msg. 3 PUSCH transmission will also be scheduled as a repeat transmission through the RAR. That is, the UE may be configured to interpret the UL grant information of the PAR provided by the base station as scheduling information for the Msg. 3 PUSCH repeat transmission. Here, the UL grant information of the PAR may include PUSCH frequency/time resource allocation information, CSI request information, etc.
Afterwards, the UE may be configured to interpret the UL grant of DCI format 0_0 used for Msg. 3 PUSCH retransmission as scheduling information for Msg. 3 PUSCH repeat transmission.
In a basic wireless communication system, if a UE transmits a preamble by selecting a preamble resource (i.e., RAPID) allocated for repeated transmission of Msg. 3 PUSCH, the UE may expect that the base station will schedule Msg. 3 PUSCH by configuring the UL grant of RAR as a field for repeated transmission of Msg 3 PUSCH. And, the UE may interpret the UL grant as a field configuration for repeated transmission of Msg. 3 PUSCH.
In addition to the operation in the basic wireless communication system described above, (regardless of the operation of the UE selecting the RAPID allocated for Msg. 3 PUSCH repetition) when the UE repeatedly transmits the preamble (by selecting the preamble repetition transmission operation), the UE may expect that the base station will schedule the Msg. 3 PUSCH by configuring the UL grant of the PAR as a field configuration for Msg. 3 PUSCH repetition transmission. That is, the UE may be configured to interpret the UL grant as a field configuration for Msg. 3 PUSCH repetition transmission.
As described above, the UE may be configured to interpret the UL grant of DCI format 0_0 used for subsequent Msg. 3 PUSCH retransmission as a field configuration for Msg. 3 PUSCH repeat transmission.
Assume that the base station detects a resource for repeated transmission of a preamble in a specific RO. At this time, the base station may determine that the UE that transmitted the preamble will perform repeated transmission of Msg. 3 PUSCH (or implicitly requests repeated transmission of Msg. 3 PUSCH), and may provide the UE with a RAR UL grant as a field configuration for repeated transmission of Msg. 3 PUSCH.
To operate as in the above-described embodiment, if the UE supports preamble repetition transmission, the UE may be configured to always support Msg. 3 PUSCH repetition transmission. As an example, the UE may transmit UE capability information indicating whether to support preamble repetition transmission/Msg. 3 PUSCH to the base station.
As another example, it may be defined that the UE implicitly reports to the base station that it is capable of repeating preamble transmissions by reporting to the base station that it is capable of repeating Msg. 3 PUSCH transmissions. If the base station also receives a report from the UE that it is capable of repeating preamble transmissions, the base station may be defined to identify the UE as a UE capable of repeating Msg. 3 PUSCH transmissions as well as repeating preamble transmissions.
Embodiment 2-2 relates to a method for configuring RACH resources that a base station configures/indicates for preamble repetition transmission.
For example, the base station may share ROs with UEs of a basic wireless communication system (hereinafter, legacy terminals) and may assign some of the preamble indices of the ROs to the UEs for repeated preamble transmission. For another example, the base station may provide a new PRACH configuration different from the PRACH configuration of the basic wireless communication system and assign an independent RO to the UEs.
As another example, the base station may configure/indicate the UE to transmit preamble repeats, all or part of the RACH resources (e.g., preamble index group or independent RO) allocated for Msg. 3 PUSCH repeat transmission. A UE that requires preamble repeat transmission may also require Msg. 3 PUSCH repeat transmission. Therefore, the base station may configure/indicate the UE to transmit preamble repeats, all or part of the RACH resources allocated for Msg. 3 PUSCH repeat transmission.
As a result, the base station may allocate all or part of the RACH resources allocated for Msg. 3 PUSCH repeated transmission to the UE for preamble repeated transmission.
For example, assume that the base station allocates N preamble indices from among the preamble indices included in a specific RO among the ROs allocated for Msg. 3 PUSCH repeated transmission. In addition, the base station may allocate M of the lowest indexes (or, from the most recent index or a specific preamble index indicated by the base station) among the N preamble indices for repeated preamble transmission.
Here, the base station may configure/indicate that the number of preamble indices allocated for preamble repetition transmission within a specific RO does not exceed the number of preamble indices allocated for Msg. 3 PUSCH repetition transmission.
As another example, assume that the base station provides independent PRACH configurations, thereby allocating ROs independent of the ROs to be used by legacy terminals for repeated transmission of Msg 3 PUSCH.
Here, the base station may additionally allocate specific L ROs among the ROs for preamble repetition transmission. Alternatively, the base station may allocate specific K preamble indices among all or some ROs allocated for Msg. 3 PUSCH repetition transmission for preamble repetition transmission. To this end, the base station may allocate a starting preamble index and/or the number of preamble indices K to the UE. As another example, the base station may allocate K lowest indices (or most recent indices) among the preamble indices to the UE for preamble repetition transmission.
Embodiment 2-3 relates to a method in which the number of repeated transmissions of Msg. 3 PUSCH is set in relation to the number of repeated transmissions of a preamble.
That is, the number of Msg. 3 PUSCH repetition transmissions that the UE may select may be determined based on the number of repetition transmissions (or, a set of repetition transmission numbers) that the UE used for preamble repetition transmission.
For example, assume that the base station configures/indicates the UE to transmit multiple repetitions for preamble repetition transmission.
Specifically, the number of repetition transmissions for preamble repetition transmission may be configured as a set of repetition transmission numbers of Msg. 3 PUSCH, and the base station may configure/indicate the number of repetition transmissions through the repetition number field of the RAR UL grant (or, Msg. 3 PUSCH retransmission UL grant of DCI format 0_0).
That is, the number of times of multiple preamble repetition transmissions may be configured/indicated/defined to correspond to a set of the number of times of multiple Msg. 3 PUSCH repetition transmissions. In other words, when the number of times of Msg. 3 PUSCH repetition transmissions is indicated by a RAR UL grant, the set of indicated values may be equal to the number of times of multiple repetition transmissions configured for preamble repetition transmissions.
For example, assume that the base station has configured four repetition transmission numbers (e.g., 1, 2, 4, and 8) for the UE for preamble repetition transmission. When the base station indicates the number of Msg. 3 PUSCH repetition transmissions through the RAR UL grant, the set of values that may be indicated can be the four repetition transmission numbers configured for preamble repetition transmission.
As another example, among the multiple preamble repetition transmission numbers configured by the base station, a previously indicated X (e.g., X=4) number of repetition transmission numbers may be configured/indicated/defined as being used as a set of the number of repetition transmissions of Msg. 3 PUSCH. The base station may configure/indicate one of the multiple preamble repetition transmission numbers as the number of repetition transmissions of Msg. 3 PUSCH to the UE using the repetition number field of the RAR UL grant (or, Msg. 3 PUSCH retransmission UL grant of DCI format 0_0).
As another example, assume that the base station does not separately set/provide the number of repetition transmissions for Msg. 3 PUSCH to the UE through RRC signaling (i.e., a predefined default value is used for Msg. 3 PUSCH).
Here, the number of repetition transmissions for Msg. 3 PUSCH may be configured differently depending on the number of repetition transmissions of the preamble selected by the UE.
Specifically, if the number of preamble repetitions selected by the UE (or configured by the base station) is N, the number of repetitions of Msg. 3 PUSCH may be configured to {a, b, c, d}(e.g., a=1, b=2, c=3, d=4). In this case, if the number of preamble repetitions selected by the UE (or configured by the base station) is 2N, the number of repetitions of Msg 3 PUSCH may be configured to {2a, 2b, 2c, 2d}.
As another example, the set for the number of Msg. 3 PUSCH repetition transmissions may be configured differently depending on the number of preamble repetition transmissions (or the number of preamble repetition transmissions corresponding to the RO selected by the UE) transmitted/selected by the UE (or configured by the base station). Accordingly, the UE may be configured to interpret the code-point of the value indicated by the base station differently based on the sets for the number of Msg. 3 PUSCH repetition transmissions that are configured differently.
That is, through the above-described method, the base station may directly configure a set of the number of repetitions of Msg. 3 PUSCH for the UE. Specifically, if the number of repetitions of the preamble transmitted/selected by the UE (or configured by the base station) is K1, the set related to the number of repetitions of Msg. 3 PUSCH may be configured to {X1, Y1, Z1, W1}. As another example, if the number of repetitions of the preamble is K2, the set related to the number of repetitions of Msg. 3 PUSCH may be configured to {X2, Y2, Z2, W2}.
It is assumed that the PRACH repetition number (set) and the Msg. 3 PUSCH repetition number (set) are indicated/configured in advance to the UE via RRC signaling, and the PRACH repetition number or/and the Msg. 3 PUSCH repetition number are fixed to a specific value (or a set of specific values) (or the UE selects one of the candidates belonging to the set of fixed values).
Here, the dynamic indication field for Msg. 3 PUSCH repetition included in the RAR UL grant (or, DCI format 0_0 for Msg 3 PUSCH retransmission) may be configured/defined to be disabled. Accordingly, the UE may interpret that the dynamic indication field for Msg. 3 PUSCH repetition is disabled, and understands and operates as a bit field in the basic wireless communication system that the RAR UL grant (or, DCI format 0_0 for Msg. 3 PUSCH) configuration is configured.
The above-described embodiments may be configured/applied to other UL signals/channels such as PUSCH/PUCCH. Information on whether the above-described embodiments are applicable (or information on the rules of the above-described proposed methods) may be defined as a rule so that the base station notifies the UE through a signal (e.g., a physical layer signal or a higher layer signal) defined/configured in advance.
Here, the UE/network side is an example and may be replaced with various devices as described with reference to
In the following description, the network side may be one base station including multiple TRPs, or may be one cell including multiple TRPs. Alternatively, the network side may include a plurality of remote radio heads (RRH)/remote radio units (RRU). For example, ideal/non-ideal backhaul may be set between TRP 1 and TRP 2, which constitute the network side. In addition, the following description is based on multiple TRPs, but it can be equally extended and applied to transmission through multiple panels/cells, and can also be extended and applied to transmission through multiple RRHs/RRUs, etc.
In addition, it is described based on a “TRP” in the following description, but as described above, a “TRP” may be applied by being substituted with an expression such as a panel, an antenna array, a cell (e.g., a macro cell/a small cell/a pico cell, etc.), a TP (transmission point), a base station (gNB, etc.), etc. As described above, a TRP may be classified according to information on a CORESET group (or a CORESET pool) (e.g., a CORESET index, an ID).
Here, the panel may refer to a unit consisting of at least one antenna, antenna port, beam, and up/downlink RS/channel resources of the UE. For example, if one UE is configured to transmit and receive with multiple TRPs (or cells), this may mean that multiple CORESET groups (or CORESET pools) are configured for one UE. Configuration of such a CORESET group (or CORESET pool) may be performed through higher layer signaling (e.g., RRC signaling, etc.).
In addition, a base station may generally mean an object which performs transmission and reception of data with a terminal. For example, the base station may be a concept which includes at least one TP (Transmission Point), at least one TRP (Transmission and Reception Point), etc. In addition, a TP and/or a TRP may include a panel, a transmission and reception unit, etc. of a base station.
Referring to
The base station may transmit remaining minimum system information (RMSI) and other system information (OSI) to the terminal (S1204). RMSI may include information required for the terminal to initially access the base station (e.g., PRACH configuration information). Here, the UE may identify the best SSB after performing SSB detection.
Thereafter, the UE may transmit a RACH preamble (Message 1, Msg1) to the base station using the PRACH resource linked/corresponding to the index (i.e., beam) of the best SSB (S1206).
The beam direction of the RACH preamble may be associated with a PRACH resource. The association between the PRACH resource (and/or the RACH preamble) and the SSB index can be established via system information (e.g., RMSI).
Here, the UE may perform PRACH preamble repetition transmission. The UE may perform PRACH preamble repetition transmission based on configuration information related to PRACH repetition transmission received from the base station.
Thereafter, as part of the RACH process, the base station may transmit a Random Access Response (RAR) (Msg2) to the terminal in response to the PRACH preamble (S1208).
The RAR may include at least one of a field related to PUSCH repeated transmission, a field for indicating whether to repeat PUSCH preamble transmission, or a PUSCH time/frequency resource field.
The UE may transmit Msg. 3 PUSCH (e.g., RRC Connection Request) using the uplink grant in the RAR (S1210).
The UE may perform PUSCH repeated transmission based on RAR. Here, the number of PUSCH repeated transmissions may be based on the number of PRACH preamble repeated transmissions.
The base station may transmit a contention resolution message (Msg4) to the terminal (S1212). Msg4 may include RRC connection setup.
When an RRC connection is established between a base station and a UE through the RACH process, subsequent beam alignment may be performed based on SSB/CSI-RS (in downlink) and SRS (in uplink). For example, the UE may receive SSB/CSI-RS (S1214). SSB/CSI-RS may be used by the UE to generate beam/CSI report.
And, the base station may request the UE to report beam/CSI through DCI (S1216). Here, the UE may generate the beam/CSI report based on SSB/CSI-RS and transmit the generated beam/CSI report to the base station through PUSCH/PUCCH (S1218) The beam/CSI report may include beam measurement results, information about preferred beams, etc. The base station and the UE may switch beams based on the beam/CSI report (S1220a, S1220b).
Thereafter, the UE and the base station may perform the embodiments described/proposed above. For example, the UE and the base station may process information in the memory and transmit a wireless signal or process a received wireless signal and store it in the memory based on the configuration information obtained in the network access procedure (e.g., system information acquisition procedure, RRC connection procedure via RACH, etc.) according to the embodiment of the present disclosure. Here, the wireless signal may include at least one of PDCCH, PDSCH, and RS (Reference Signal) in the case of downlink, and at least one of PUCCH, PUSCH, and SRS in the case of uplink.
General Device to which the Present Disclosure May be Applied
In reference to
A first device 100 may include one or more processors 102 and one or more memories 104 and may additionally include one or more transceivers 106 and/or one or more antennas 108. A processor 102 may control a memory 104 and/or a transceiver 106 and may be configured to implement description, functions, procedures, proposals, methods and/or operation flow charts included in the present disclosure.
For example, a processor 102 may transmit a wireless signal including first information/signal through a transceiver 106 after generating first information/signal by processing information in a memory 104. In addition, a processor 102 may receive a wireless signal including second information/signal through a transceiver 106 and then store information obtained by signal processing of second information/signal in a memory 104.
A memory 104 may be connected to a processor 102 and may store a variety of information related to an operation of a processor 102. For example, a memory 104 may store a software code including commands for performing all or part of processes controlled by a processor 102 or for performing description, functions, procedures, proposals, methods and/or operation flow charts included in the present disclosure. Here, a processor 102 and a memory 104 may be part of a communication modem/circuit/chip designed to implement a wireless communication technology (e.g., LTE, NR). A transceiver 106 may be connected to a processor 102 and may transmit and/or receive a wireless signal through one or more antennas 108. A transceiver 106 may include a transmitter and/or a receiver. A transceiver 106 may be used together with a RF (Radio Frequency) unit. In the present disclosure, a wireless device may mean a communication modem/circuit/chip.
A second device 200 may include one or more processors 202 and one or more memories 204 and may additionally include one or more transceivers 206 and/or one or more antennas 208. A processor 202 may control a memory 204 and/or a transceiver 206 and may be configured to implement description, functions, procedures, proposals, methods and/or operation flows charts included in the present disclosure. For example, a processor 202 may generate third information/signal by processing information in a memory 204, and then transmit a wireless signal including third information/signal through a transceiver 206. In addition, a processor 202 may receive a wireless signal including fourth information/signal through a transceiver 206, and then store information obtained by signal processing of fourth information/signal in a memory 204. A memory 204 may be connected to a processor 202 and may store a variety of information related to an operation of a processor 202. For example, a memory 204 may store a software code including commands for performing all or part of processes controlled by a processor 202 or for performing description, functions, procedures, proposals, methods and/or operation flow charts included in the present disclosure. Here, a processor 202 and a memory 204 may be part of a communication modem/circuit/chip designed to implement a wireless communication technology (e.g., LTE, NR). A transceiver 206 may be connected to a processor 202 and may transmit and/or receive a wireless signal through one or more antennas 208. A transceiver 206 may include a transmitter and/or a receiver. A transceiver 206 may be used together with a RF unit. In the present disclosure, a wireless device may mean a communication modem/circuit/chip.
Hereinafter, a hardware element of a device 100, 200 will be described in more detail. It is not limited thereto, but one or more protocol layers may be implemented by one or more processors 102, 202. For example, one or more processors 102, 202 may implement one or more layers (e.g., a functional layer such as PHY, MAC, RLC, PDCP, RRC, SDAP). One or more processors 102, 202 may generate one or more PDUs (Protocol Data Unit) and/or one or more SDUs (Service Data Unit) according to description, functions, procedures, proposals, methods and/or operation flow charts included in the present disclosure. One or more processors 102, 202 may generate a message, control information, data or information according to description, functions, procedures, proposals, methods and/or operation flow charts included in the present disclosure. One or more processors 102, 202 may generate a signal (e.g., a baseband signal) including a PDU, a SDU, a message, control information, data or information according to functions, procedures, proposals and/or methods disclosed in the present disclosure to provide it to one or more transceivers 106, 206.
One or more processors 102, 202 may receive a signal (e.g., a baseband signal) from one or more transceivers 106, 206 and obtain a PDU, a SDU, a message, control information, data or information according to description, functions, procedures, proposals, methods and/or operation flow charts included in the present disclosure. One or more processors 102, 202 may be referred to as a controller, a micro controller, a micro processor or a micro computer. One or more processors 102, 202 may be implemented by a hardware, a firmware, a software, or their combination. In an example, one or more ASICs (Application Specific Integrated Circuit), one or more DSPs (Digital Signal Processor), one or more DSPDs (Digital Signal Processing Device), one or more PLDs (Programmable Logic Device) or one or more FPGAs (Field Programmable Gate Arrays) may be included in one or more processors 102, 202. Description, functions, procedures, proposals, methods and/or operation flow charts included in the present disclosure may be implemented by using a firmware or a software and a firmware or a software may be implemented to include a module, a procedure, a function, etc. A firmware or a software configured to perform description, functions, procedures, proposals, methods and/or operation flow charts included in the present disclosure may be included in one or more processors 102, 202 or may be stored in one or more memories 104, 204 and driven by one or more processors 102, 202. Description, functions, procedures, proposals, methods and/or operation flow charts included in the present disclosure may be implemented by using a firmware or a software in a form of a code, a command and/or a set of commands.
One or more memories 104, 204 may be connected to one or more processors 102, 202 and may store data, a signal, a message, information, a program, a code, an instruction and/or a command in various forms. One or more memories 104, 204 may be configured with ROM, RAM, EPROM, a flash memory, a hard drive, a register, a cash memory, a computer readable storage medium and/or their combination. One or more memories 104, 204 may be positioned inside and/or outside one or more processors 102, 202. In addition, one or more memories 104, 204 may be connected to one or more processors 102, 202 through a variety of technologies such as a wire or wireless connection.
One or more transceivers 106, 206 may transmit user data, control information, a wireless signal/channel, etc. mentioned in methods and/or operation flow charts, etc. of the present disclosure to one or more other devices. One or more transceivers 106, 206 may receiver user data, control information, a wireless signal/channel, etc. mentioned in description, functions, procedures, proposals, methods and/or operation flow charts, etc. included in the present disclosure from one or more other devices. For example, one or more transceivers 106, 206 may be connected to one or more processors 102, 202 and may transmit and receive a wireless signal. For example, one or more processors 102, 202 may control one or more transceivers 106, 206 to transmit user data, control information or a wireless signal to one or more other devices. In addition, one or more processors 102, 202 may control one or more transceivers 106, 206 to receive user data, control information or a wireless signal from one or more other devices. In addition, one or more transceivers 106, 206 may be connected to one or more antennas 108, 208 and one or more transceivers 106, 206 may be configured to transmit and receive user data, control information, a wireless signal/channel, etc. mentioned in description, functions, procedures, proposals, methods and/or operation flow charts, etc. included in the present disclosure through one or more antennas 108, 208. In the present disclosure, one or more antennas may be a plurality of physical antennas or a plurality of logical antennas (e.g., an antenna port). One or more transceivers 106, 206 may convert a received wireless signal/channel, etc. into a baseband signal from a RF band signal to process received user data, control information, wireless signal/channel, etc. by using one or more processors 102, 202. One or more transceivers 106, 206 may convert user data, control information, a wireless signal/channel, etc. which are processed by using one or more processors 102, 202 from a baseband signal to a RF band signal. Therefore, one or more transceivers 106, 206 may include an (analogue) oscillator and/or a filter.
Embodiments described above are that elements and features of the present disclosure are combined in a predetermined form. Each element or feature should be considered to be optional unless otherwise explicitly mentioned. Each element or feature may be implemented in a form that it is not combined with other element or feature. In addition, an embodiment of the present disclosure may include combining a part of elements and/or features. An order of operations described in embodiments of the present disclosure may be changed. Some elements or features of one embodiment may be included in other embodiment or may be substituted with a corresponding element or a feature of other embodiment. It is clear that an embodiment may include combining claims without an explicit dependency relationship in claims or may be included as a new claim by amendment after application.
It is clear to a person skilled in the pertinent art that the present disclosure may be implemented in other specific form in a scope not going beyond an essential feature of the present disclosure. Accordingly, the above-described detailed description should not be restrictively construed in every aspect and should be considered to be illustrative. A scope of the present disclosure should be determined by reasonable construction of an attached claim and all changes within an equivalent scope of the present disclosure are included in a scope of the present disclosure
A scope of the present disclosure includes software or machine-executable commands (e.g., an operating system, an application, a firmware, a program, etc.) which execute an operation according to a method of various embodiments in a device or a computer and a non-transitory computer-readable medium that such a software or a command, etc. are stored and are executable in a device or a computer. A command which may be used to program a processing system performing a feature described in the present disclosure may be stored in a storage medium or a computer-readable storage medium and a feature described in the present disclosure may be implemented by using a computer program product including such a storage medium. A storage medium may include a high-speed random-access memory such as DRAM, SRAM, DDR RAM or other random-access solid state memory device, but it is not limited thereto, and it may include a nonvolatile memory such as one or more magnetic disk storage devices, optical disk storage devices, flash memory devices or other nonvolatile solid state storage devices. A memory optionally includes one or more storage devices positioned remotely from processor(s). A memory or alternatively, nonvolatile memory device(s) in a memory include a non-transitory computer-readable storage medium. A feature described in the present disclosure may be stored in any one of machine-readable mediums to control a hardware of a processing system and may be integrated into a software and/or a firmware which allows a processing system to interact with other mechanism utilizing a result from an embodiment of the present disclosure. Such a software or a firmware may include an application code, a device driver, an operating system and an execution environment/container, but it is not limited thereto.
Here, a wireless communication technology implemented in a device 100, 200 of the present disclosure may include Narrowband Internet of Things for a low-power communication as well as LTE, NR and 6G. Here, for example, an NB-IoT technology may be an example of a LPWAN (Low Power Wide Area Network) technology, may be implemented in a standard of LTE Cat NB1 and/or LTE Cat NB2, etc. and is not limited to the above-described name. Additionally or alternatively, a wireless communication technology implemented in a wireless device 100, 200 of the present disclosure may perform a communication based on a LTE-M technology. Here, in an example, a LTE-M technology may be an example of a LPWAN technology and may be referred to a variety of names such as an eMTC (enhanced Machine Type Communication), etc. For example, an LTE-M technology may be implemented in at least any one of various standards including 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (non-Bandwidth Limited), 5) LTE-MTC, 6) LTE Machine Type Communication, and/or 7) LTE M and so on and it is not limited to the above-described name. Additionally or alternatively, a wireless communication technology implemented in a wireless device 100, 200 of the present disclosure may include at least any one of a ZigBee, a Bluetooth and a low power wide area network (LPWAN) considering a low-power communication and it is not limited to the above-described name. In an example, a ZigBee technology may generate PAN (personal area networks) related to a small/low-power digital communication based on a variety of standards such as IEEE 802.15.4, etc. and may be referred to as a variety of names.
A method proposed by the present disclosure is mainly described based on an example applied to 3GPP LTE/LTE-A, 5G system, but may be applied to various wireless communication systems other than the 3GPP LTE/LTE-A, 5G system.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2022-0024528 | Feb 2022 | KR | national |
| 10-2022-0052398 | Apr 2022 | KR | national |
This application is a National Stage application under 35 U.S.C. § 371 of International Application No. PCT/KR2023/002410, filed on Feb. 20, 2023, which claims the benefit of earlier filing date and right of priority to KR Application No. 10-2022-0024528, filed on Feb. 24, 2022, and KR Application No. 10-2022-0052398, filed on Apr. 27, 2022 the contents of which are all hereby incorporated by reference herein in their entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/KR2023/002410 | 2/20/2023 | WO |
