CN117812716A

CN117812716A - Method and user equipment for wireless communication

Info

Publication number: CN117812716A
Application number: CN202311223057.3A
Authority: CN
Inventors: 程俊强; 陈滔
Original assignee: MediaTek Singapore Pte Ltd
Current assignee: MediaTek Singapore Pte Ltd
Priority date: 2022-09-30
Filing date: 2023-09-20
Publication date: 2024-04-02
Also published as: WO2024065730A1

Abstract

Methods and UEs for wireless communication are provided. Supporting transmission starting at one and/or more starting symbols within a slot. The PSCCH is configured to be transmitted on each starting symbol within the slot. Alternatively, only the PSSCH is transmitted on the other starting symbols except the first starting symbol in the slot. The PSCCH is transmitted on the lowest subchannel of each RB set occupying BWP. Or, the PSCCH is transmitted on the lowest subchannel of the lowest RB set. The UE performs a type 1 channel access procedure before there is no PSFCH transmission available for the shared COT and performs one of a type 2A/2B/2C channel access procedure before there is a PSFCH transmission available for the shared COT. By using the present invention, wireless communication can be performed better.

Description

Method and user equipment for wireless communication

Technical Field

The present invention relates to wireless communications, and more particularly to Sidelink (SL) communication transmissions over unlicensed spectrum (unlicensed spectrum).

Background

Side-link communications are introduced to enable direct transmission between two User Equipments (UEs), which may also be referred to as device-to-device (D2D) communications. With the progress of 3GPP specification work, the scenario of side-links expands to UE-to-network relay, public safety, vehicle-to-infrastructure (V2X) communication, and so on. The key role of the sidelink in long term evolution (long term evolution, LTE) and New Radio (NR) makes it a necessary improvement in supporting various use cases for future wireless communications.

In order to meet the increasing demand for wireless data services (traffic), the use of unlicensed bands has attracted widespread attention in the wireless industry to increase the capacity of future wireless communication systems. The use of unlicensed spectrum for sidelink communications is considered the most promising direction for the further development of sidelink communications. In order to occupy the unlicensed band for side-link transceiving, the UE needs to perform channel sensing, such as listen-before-talk (LBT) procedure. The sensing procedure places additional demands on the side-link transceivers and requires that the SL-U resources be allocated, used and configured more efficiently.

Improvements and enhancements to side-link resource allocation and resource usage in unlicensed bands are needed.

Disclosure of Invention

Apparatus and methods may be provided for SL transmission in a SL-U. In a novel aspect, one or more start symbols of a SL-U within a slot are supported to start transmission. In one embodiment, the PSCCH is configured to be transmitted on each starting symbol within the slot. In another embodiment, only the PSSCH is transmitted on the other starting symbols in the slot except the first starting symbol. In one embodiment, the control indicator indicates the PSSCH in the current complete slot when the PSCCH is preconfigured to start at any starting symbol within the slot. In another embodiment, the control indicator indicates the PSSCH in the past partial slot when the PSCCH is preconfigured to start only at the first starting symbol within the slot. In one embodiment, the control indicator is carried in at least one control message, the at least one control message including a first SCI and a second SCI. In another embodiment, the control indicator further indicates one or more elements comprising: symbol length, repetition configuration, combining configuration, and PSSCH DMRS.

In another novel aspect, the PSCCH is transmitted within one subchannel. In one embodiment, the PSCCH is transmitted on a fixed subchannel occupying each RB set of BWP. In another embodiment, the PSCCH is transmitted on a fixed subchannel of a pre-configured set of RBs. In one embodiment, the preconfigured one RB set is the lowest RB set occupied by the UE.

In another novel aspect, the UE establishes a SL connection with another device in the SL-U, performs LBT, and sets the cap value of the PSFCH to 1. In one embodiment, type 1 channel access is performed for the PSFCH.

By using the present invention, wireless communication can be performed better.

Other embodiments and advantages will be described in the detailed description that follows. This summary is not intended to define the invention. The invention is defined by the claims.

Drawings

The figures may illustrate embodiments of the invention, wherein like numerals may refer to like elements throughout.

Fig. 1 illustrates a system diagram showing an exemplary wireless network for side-link data communication in unlicensed bands according to an embodiment of the present invention.

Fig. 2 shows a schematic diagram of a start symbol configuration with multiple start symbols and PSSCH processing according to an embodiment of the present invention.

Fig. 3 shows a schematic diagram of a start symbol configuration and corresponding control indications according to an embodiment of the invention.

Fig. 4 shows a schematic diagram of a sub-channel and RB set configuration of a PSCCH of a UE for SL-U transceiving, where the UE is configured with occupied BWP, according to an embodiment of the present invention.

Fig. 5 shows a schematic diagram of a PSCCH configuration with one or more RB sets in an occupied BWP for SL-U transceiving by a UE, according to an embodiment of the present invention.

Fig. 6 shows a schematic diagram of a PSFCH configuration for SL-U transceiving according to an embodiment of the present invention.

Fig. 7 shows an exemplary flow chart for a UE to configure PSCCH with occupied BWP for SL-U transceiving according to an embodiment of the present invention.

Fig. 8 shows an exemplary flow chart for a UE to configure a PSSCH with multiple start symbols for SL-U transceiving according to an embodiment of the present invention.

Fig. 9 shows an exemplary flow chart for a UE configuring a PSFCH for SL-U transceiving according to an embodiment of the present invention.

Detailed Description

Reference will now be made in detail to some embodiments of the invention, examples of which are illustrated in the accompanying drawings.

Fig. 1 illustrates a system diagram showing an exemplary wireless network for side-link data communication in unlicensed bands according to an embodiment of the present invention. The wireless network 100 includes a plurality of communication devices or mobile stations, such as User Equipment (UEs) 111, 112, 113, 114, and 115, configured with side links in unlicensed bands. An exemplary mobile device in wireless network 100 has side-link capabilities. Side-link communication refers to direct communication between end nodes or UEs, data not passing through the network. For example, UE 113 communicates directly with UE 114, rather than through a link with a network element. The range of the side-uplink transmission also supports UE-to-network relay to extend the service range of the eNB/gNB, where the in-coverage UE acts as a relay node between the eNB/gNB and the out-of-coverage UE. For example, UE 112 connects with base station 101 through an access link. UE 112 provides network access to out-of-coverage UE 111 through side-uplink relay. A base station, such as base station 101, may also be referred to as an access point, an access terminal, a base station, node B, eNB, gNB, or other terminology used in the art. The network can be a homogeneous network or a heterogeneous network, and can be deployed in the same frequency or different frequencies. Base station 101 is an exemplary base station. With the demand for greater capacity and the development of side-link communications, it is important that side-link devices use unlicensed bands and coexist in harmony with devices of other radio access technologies (radio access technology, RAT) operating in the same unlicensed band. For example, neighboring UEs 116 and 117 communicate with base station 102 via other RATs (e.g., wi-Fi) that share the same unlicensed band. Adjacent UEs 118 and 119 communicate with base station 103 via other RATs (e.g., NRs) sharing the same unlicensed band.

For SL-U, in the time domain, it is considered that channel access operations (e.g., LBT) may succeed in the middle of a slot. For a conventional NR-U, the gNB/UE may access the channel at the symbol level after the channel access is completed, which may improve the channel access efficiency when competing with other RATs (e.g., wiFi). For conventional SL, the smallest unit of scheduling is a slot, which means that even if LBT is completed in one slot, transmission can only start at the next slot boundary. The gap between LBT end position and transmission start position increases the risk of losing channel occupancy time (channel occupancy time, COT). It is therefore necessary to introduce additional start symbols in the SL-U slot to increase the channel access opportunities. Accordingly, the necessary enhancement mechanisms (e.g., slot structure, physical side-uplink control channel (Physical Sidelink Control Channel, PSCCH)/physical side-uplink shared channel (Physical Sidelink Shared Channel, PSSCH)) need to be redesigned to better support the SL-U.

Fig. 1 also shows a simplified block diagram of a mobile device/UE for operating in the unlicensed frequency band. UE 111 has an antenna 125 that transmits and receives radio signals. A Radio Frequency (RF) transceiver circuit 123 is coupled to the antenna, receives RF signals from the antenna 125, converts them to baseband signals, and sends them to the processor 122. In one embodiment, the RF transceiver may include two RF modules (not shown). The RF transceiver 123 also converts the baseband signal received from the processor 122 into an RF signal and transmits it to the antenna 125. The processor 122 processes the received baseband signals and invokes different functional modules to perform functions in the UE 111. Memory (or storage medium or computer readable medium) 121 stores program instructions and data 126 to control operation of UE 111. The antenna 125 sends uplink transmissions to the base station and receives downlink transmissions from the base station.

UE 111 also includes a set of control modules for performing functional tasks. UE 111 may include only a subset of the set of control modules to perform one or more functional tasks. The set of control modules may be implemented in circuitry, software, firmware, or a combination thereof. A bandwidth part (BWP) module 191 may determine BWP for SL-U transceiving, wherein the BWP is configured with one or more Resource Block (RB) sets each having a plurality of subchannels. PSCCH configuration module 192 prepares PSCCH transmissions on one or more sets of RBs to communicate with a second UE over a SL connection. The PSCCH controller 193 transmits PSCCH on one or more pre-configured locations based on occupancy BWP (occupied BWP) configuration, wherein a subset or all of the configured set of RBs of the BWP are occupied by the UE. The start symbol configuration module 194 determines a plurality of candidate start symbols within a slot for SL transceiving in the wireless network, wherein the SL transceiving is SL-U transceiving. In one embodiment, the start symbol is determined based on a network configuration. In another embodiment, the starting symbol is determined by the UE. In one embodiment, the configuration module 194 determines a first candidate starting symbol and a second candidate starting symbol within one slot for SL transceiving in the wireless network, wherein the SL transceiving is on an unlicensed band. The channel access module 195 performs channel access before SL-U transceiving. PSCCH indication controller 196 transmits a PSCCH at a pre-configured starting symbol when the channel access procedure is successful, where a control indicator indicates the starting position of the PSCCH based on the pre-configured starting symbol for the PSCCH. SL-U controller 197 establishes a SL connection for SL-U transceiving in the wireless network. The physical side uplink feedback channel (Physical Sidelink Feedback Channel, PSFCH) controller 198 configures the cap value of the PSFCH to 1 and transmits the PSFCH when channel access is successful.

Fig. 2 shows a schematic diagram of a start symbol configuration and PSSCH processing for a mobile station having a plurality of start symbols according to an embodiment of the present invention. In a novel aspect, one or more start symbols within a slot are supported in a SL-U. Exemplary symbols #0 and #8 are configured as candidate start symbols. The exemplary slot N201 has 14 symbols. In slot N201, start symbols 211 and 212 may be configured. The next slot after slot N201 is slot n+1 202. Similarly, symbols #0 (213) and #8 (not shown) are configured as start symbols. In step 231, LBT starts at symbol #3 in slot N201. In step 232, LBT ends/succeeds in symbol #5 of slot N201. In one embodiment, a cyclic prefix extension (cyclic prefix extension, CPE) 233 is sent between the successful end of the LBT and the next starting symbol. CPE operation may be implemented to achieve microsecond to symbol boundary alignment so that the SL-U UE may begin transmitting on the channel immediately after the LBT procedure is completed. In one embodiment, at least the first start symbol is configured for automatic gain control purposes.

In one embodiment 210, the PSCCH may be transmitted on each starting symbol within a slot. In one embodiment, the PSCCH is preconfigured to start at any candidate starting symbol within the slot closest to the LBT procedure success. For example, PSCCH may begin on symbols 211, 212, and 213. At the end of the CPE, the PSCCH may be transmitted on the second starting symbol 212 of slot N201. The control indicator may indicate the PSSCH in the current full slot.

In another embodiment 220, the PSCCH is preconfigured to start only at the first starting symbol within the slot. For example, LBT succeeds in slot N201, where slot N201 is configured with start symbols 221 and 222. Similarly, the subsequent slot n+1 202 is configured with a start symbol at symbols #0 (223) and #8 (not shown). In this embodiment, the start symbols 221 and 223 may be used for the PSCCH. The start symbol 222 is not the first candidate start symbol for the slot and may be used only for the PSSCH. Since PSSCH transmissions are only made from other starting symbols than the first starting symbol, the UE may configure multiple starting symbols within one slot to achieve SL-U with comparable channel access capabilities to other RATs (e.g., wiFi and/or NR-U). In addition, in case only PSSCH (repetition) transmission is allowed on the other starting symbols than the first starting symbol within the slot, UE complexity and power consumption can be reduced due to blind detection/decoding of the PSCCH. The control indicator indicates the PSSCH in the past partial slot. The PSCCH located in the first starting symbol (e.g., starting symbol 223) of a complete slot indicates information and/or configuration of the past (partial) slot (e.g., slot N201 starting from starting symbol 222) as well as the current (slot n+1 202) and/or subsequent PSCCHs in the complete slot. In one embodiment, the PSCCH and PSSCH transmissions on the second starting symbol are different transport blocks than those transmitted in the subsequent full slot. In another embodiment, the PSCCH and PSSCH transmissions on the second starting symbol are repetitions of a subset of transport blocks transmitted in a subsequent full slot.

Fig. 3 shows a schematic diagram of a start symbol configuration and corresponding control indications according to an embodiment of the invention. In step 301, the ue determines one or more starting symbols within a slot. In one embodiment, one or two start symbols may be configured. In one embodiment 302, the control indicator indicates the corresponding PSSCH according to the configuration of the starting symbol. In one embodiment, the control indicator is carried in the first side uplink control indicator (sidelink control indicator, SCI) and/or the second SCI. For example, the configuration of the PSSCH in the portion and/or one or more slots can be indicated with additional bits (bits in the reserved bits) in the first SCI and/or the second SCI, respectively. Alternatively, it may be indicated by both the first SCI and the second SCI. For example, an additional bit in the first SCI may be used to indicate whether the current control is used only for the PSSCH in the current slot or for the PSSCH in the current slot and in the past (partial) slots. For the latter case, an indication of other configurations of the PSSCH can be carried and found in the second SCI. The bitmap and/or table may be (pre) configured and/or indicated to show the PSSCH configuration.

In one embodiment, the control indicators and/or configurations described above may include one or more elements including a starting position/offset of a symbol, and/or a starting symbol, and/or a symbol length, and/or configuration, repetition, combining, and demodulation reference signals (demodulation reference signal, DMRS) of an automatic gain control (automatic gain control, AGC). For example, the start symbol may be indicated for AGC/combining purposes.

In one embodiment 310, a UE configured with a PSCCH may start on any candidate starting symbol. In one embodiment, when the UE detects and decodes a control signal in one candidate start symbol of a slot, the UE may ignore control signals on other candidate start symbols in the slot. In one embodiment, when more than one candidate starting symbol is (pre) configured within a slot, the control signal/channel may be (pre) configured to be transmitted on multiple fixed symbols and/or on each starting symbol. For example, slot N305 and slot n+1 306 may be two consecutive slots that are used as SL resources. More than one candidate start symbol may be configured, such as symbols #0, #5, and #10. When the control indicator indicates that the PSCCH may be started on any candidate starting symbol, the UE may be configured to monitor each starting symbol within the slot. When the UE is (pre) configured to monitor a plurality of start symbols (e.g. symbols #0, #5 and # 10), the UE may decode only the (first) M control signals in one slot, as in the (pre) configuration. For example, the UE may be (pre) configured to decode only one control signal in each starting symbol. In step 311, the ue detects a control signal. In step 312, the ue may ignore control signals that may be present at symbols #5 and #10.

In one embodiment 320, the UE may be configured with PSCCH only on the first candidate starting symbol in the slot. The control indicator indicates the PSSCH in the past partial slot. For example, slot N307 and slot n+1 308 are two consecutive slots that are used as SL resources. More than one candidate start symbol may be configured, such as symbols #0, #5, and #10. When the PSCCH is configured to start only on the first candidate starting symbol, only symbol #0 carries the PSCCH. In one example, the PSCCH starts on symbol #0 of slot n+1 308. In one embodiment 321, the PSCCH from slot n+1 308 may indicate a past partial slot, which is symbols #10 to #13 of slot N307. In one embodiment 322, duplicate data may be sent over a past partial time slot.

In one embodiment 330, the UE may be (pre) configured with one or more additional PSSCH elements, including whether to buffer the PSSCH, how much to buffer in the past partial slots. The additional PSSCH element may be determined based on one or more factors including UE capabilities, UE capability reports, and UE implementation. In one embodiment, the UE may buffer all data/PSSCHs in the past (partial) slot and the current full slot to obtain the best combined performance. In another embodiment, the UE may buffer partial data/PSSCH in the past (partial) slot and all data/PSSCH in the current full slot to achieve a tradeoff between performance and buffer storage. In yet another embodiment, the UE may buffer only the PSSCH in the current full slot to achieve low buffering.

In a novel aspect, for PSCCH/PSSCH channel structure design, the sub-channels may be used as granularity of the frequency domain. For interlace-based transmission, 1 subchannel is equal to K interlaces in 1 RB set for interlace-RB based transmission, where K is (pre) configured. For a continuous-based transmission, 1 subchannel is equal to N consecutive RBs within 1 RB set for continuous-RB based transmission. In one embodiment, N is (pre) configured.

Fig. 4 shows a schematic diagram of a sub-channel and RB set configuration of a PSCCH of a UE for SL-U transceiving, where the UE is configured with occupied BWP, according to an embodiment of the present invention. In one embodiment, the UE is configured with BWP for SL transceiving in SL-U. In one embodiment, the BWP is configured by the network. The UE receives the BWP configuration from the network and determines the BWP accordingly. In another embodiment, the BWP is determined by the UE. For example, UE-1 establishes a SL connection with UE-2. SL BWP may have three RB sets, namely RB set 0 401, RB set 1 402, RB set 2 403. In scenario 410, each of UE-1 and UE-2 is configured with an occupied BWP, UE-1BWP 411 and UE-2BWP 412, respectively. BWP 411 and BWP 412 occupy RB set 0 401 and RB set 1 402. When UE-1 and UE-2 are configured with the same PSCCH subchannel configuration, UE-1 and UE-2 may detect the PSCCH. In scenario 420, each of UE-1 and UE-2 is configured with an occupied BWP, UE-1BWP 421 and UE-2BWP 422, respectively. BWP 421 occupies RB set 1 402 and RB set 2 403.BWP 422 occupies RB set 0 401 and RB set 1 402. When UE-1 and UE-2 are configured with the same PSCCH subchannel configuration, UE-1 and UE-2 may not be able to detect the PSCCH of the other UE. Similarly, in the context 430, each of UE-1 and UE-2 may be configured with an occupied BWP, UE-1BWP 431 and UE-2BWP 432, respectively. BWP 431 occupies RB set 0 401 and RB set 1 402.BWP 432 occupies RB set 1 402. When UE-1 and UE-2 are configured with the same PSCCH subchannel configuration, UE-1 and UE-2 may not be able to detect the PSCCH of the other UE.

In one novel aspect, a UE transmits PSCCH at one or more pre-configured locations based on an occupied BWP configuration, wherein a subset of the configured BWP or the entire set of RBs is occupied by the UE. In one embodiment, the PSCCH may be transmitted in a fixed subchannel. For example, for the case where the Tx UE uses multiple RB sets, the PSCCH may be transmitted within 1 fixed subchannel (e.g., first/lowest subchannel) of 1 RB set (e.g., first/lowest RB set) of the occupied multiple RB sets, and/or the PSCCH may be transmitted within 1 fixed subchannel (e.g., first/lowest subchannel) of each RB set of the occupied bandwidth. In addition, the PSCCH may be located in a subchannel having the smallest index among the subchannels of the corresponding PSCCH. In one embodiment, the PSCCH may be transmitted on the lowest subchannel of each set of resource blocks of a corresponding PSCCH. In another embodiment, the PSCCH may be transmitted on the lowest subchannel of the lowest set of resource blocks of the corresponding PSCCH. In step 461, the ue configures BWP for SL transceiving on the SL-U, wherein the BWP is configured with one or more RB sets, each RB set having a plurality of subchannels. BWP may be configured based on UE capabilities. The occupied BWP may also be based on the configuration of the SL transceiving. In step 462, the UE prepares/pre-configures PSCCH transmissions on one or more RB sets to communicate with a second UE over a SL connection. In one embodiment, the PSCCH is transmitted on fixed subchannels of each occupied RB set of one or more RB sets. In one embodiment, the PSCCH is transmitted on the lowest subchannel of each RB set. In one embodiment, the PSCCH is transmitted on a fixed subchannel of a pre-configured set of RBs. In one embodiment, the preconfigured set of RBs is the lowest set of RBs occupied by the UE. In another embodiment, one or more pre-configured locations may also be determined based on the COT. For example, the PSSCH may start from the first/lowest sub-channel of the occupied (total) bandwidth for out-of-COT operation and/or for transmissions immediately after and/or closest to the end of the LBT. For intra-COT operation, the PSSCH may be scheduled (e.g., by the COT initiator) to start from the first/lowest subchannel of the indicated/scheduled/allocated bandwidth. In one embodiment, the PSCCH starts with a subchannel over an RB set or multiple RB sets of the respective PSSCH scheduled by the COT initiator UE. In step 463, the ue may monitor the preconfigured PSCCH location to obtain control information. In one embodiment, the UE may detect the PSCCH based on a PSCCH location corresponding to a corresponding PSCCH. In one embodiment, when a PSCCH is detected, the UE ignores the subsequent PSCCH location.

Fig. 5 shows a schematic diagram of a PSCCH configuration with one or more RB sets in an occupied BWP for SL-U transceiving by a UE, according to an embodiment of the present invention. For example, the SL-U bandwidth may be configured with three RB sets: RB set 0 501, RB set 1 502, and RB set 2 503. In one embodiment 591, the PSCCH is transmitted on a fixed subchannel of a pre-configured set of RBs, where the pre-configured set of RBs is the lowest set of RBs occupied by the UE. For example, a UE with occupied BWP 510 may occupy RB set 0 501 and RB set 1 502, where the PSCCH may be configured at subchannel 511, with subchannel 511 being the lowest subchannel of the lowest RBs of BWP 510. Similarly, a UE occupying BWP 520 may occupy RB set 1 502 and RB set 2 503, where PSCCH may be configured at subchannel 521, the subchannel 521 being the lowest subchannel of the lowest RBs of BWP 520. A UE occupying BWP 530 may occupy RB set 1 502, where the PSCCH may be configured at subchannel 531, subchannel 531 being the lowest subchannel of the lowest RBs of BWP 530. A UE occupying BWP 540 may occupy RB set 0 501, RB set 1 502, RB set 2 503, where PSCCH may be configured at subchannel 541, subchannel 541 being the lowest subchannel of the lowest RBs of BWP 540.

In one embodiment 592, the PSCCH may be transmitted on fixed subchannels of each occupied RB set of one or more RB sets. In one embodiment, the fixed subchannel is the lowest subchannel of the RB set. For example, a UE occupying BWP 550 may occupy RB set 0 501 and RB set 1 502, with PSCCHs configured at subchannels 551 and 552. Similarly, a UE occupying BWP 560 may occupy RB set 1 502 and RB set 2 503, where PSCCH may be configured at subchannels 561 and 562. A UE occupying BWP 570 may occupy RB set 1 502, with PSCCH configured at subchannel 571. A UE occupying BWP 580 may occupy RB set 0 501, RB set 1 502, RB set 2 503, with PSCCHs configured at subchannels 581, 582, and 583.

Fig. 6 shows a schematic diagram of a PSFCH configuration for SL-U transceiving according to an embodiment of the present invention. In one novel aspect, a UE may establish a SL connection on a SL-U, perform channel access prior to transmitting a PSFCH, configure a channel access priority (channel access priority class, CPAC) value of the PSFCH to 1, and transmit the PSFCH when the channel access is successful. For transmission of the PSFCH, it may be (pre) configured to perform a type 1 channel access procedure without shared channel occupation and a type 2 channel access procedure with shared channel occupation. In one embodiment, the CAPC value of the PSFCH may be set to "1". In another embodiment, the CPACs are set to be the same as the corresponding PSSCHs based on the (pre) configuration. In step 601, the ue performs channel access. In step 602, when channel access is successful, the UE prepares for PSFCH transmission. In one embodiment 610, the CAPC value is set to "1". In step 620, the ue determines whether it is a shared channel occupation. If step 620 determines no, the UE performs type 1 channel access. In one embodiment, when the UE performs type 1 channel access for the PSFCH, the CAPC for the PSFCH may be set to "1". If step 620 determines yes, the UE performs one of the type 2A/2B/2C channel accesses. In another embodiment, for transmission of side-uplink synchronization signal blocks (sidelink synchronization signal block, S-SSB) in SL-U, it may be (pre) configured that S-SSB may be sent without sensing the channel.

Fig. 7 shows an exemplary flow chart for a UE to configure PSCCH with occupied BWP for SL-U transceiving according to an embodiment of the present invention. In step 701, the ue determines BWP for SL-U transceiving, wherein the BWP is configured with one or more RB sets, each RB set having a plurality of subchannels. In step 702, the UE prepares a PSSCH transmission over one or more RB sets to communicate with a second UE over a SL connection. In step 703, the ue transmits or receives a PSCCH corresponding to the PSSCH transmission in a subset of one or more RB sets occupied by the PSSCH transmission.

Fig. 8 shows an exemplary flow chart for a UE to configure a PSSCH with multiple start symbols for SL-U transceiving according to an embodiment of the present invention. In step 801, a ue determines a first starting symbol and a second starting symbol in a slot in a wireless network for SL transceiving, wherein the SL transceiving is SL-U transceiving. In step 802, the ue performs a channel access procedure before SL-U transceiving. In step 803, when the channel access procedure is successful, the UE transmits or receives the PSCCH at the first or second starting symbol within the slot.

Fig. 9 shows an exemplary flow chart for a UE configuring a PSFCH for SL-U transceiving according to an embodiment of the present invention. In step 901, the ue establishes a SL connection over an unlicensed band for SL-U transceiving in a wireless network. In step 902, the ue performs a type 1 channel access procedure before there is no PSFCH transmission for which a shared COT is available, and performs one of a type 2A/2B/2C channel access procedure before there is a PSFCH transmission for which a shared COT is available. In step 903, the ue transmits the PSFCH when the channel access procedure is successful.

Although the invention has been described above in connection with specific embodiments for instructional purposes, the invention is not limited thereto. Accordingly, various modifications, adaptations, and combinations of the various features of the described embodiments can be practiced without departing from the scope of the invention as set forth in the claims.

Claims

1. A method for wireless communication, wherein the method comprises:

determining a bandwidth portion for side-uplink transceiving on an unlicensed spectrum, wherein the bandwidth portion is configured with one or more sets of resource blocks, each set of resource blocks having a plurality of subchannels;

preparing a physical sidelink shared channel transmission on the set of one or more resource blocks for communication with a second user equipment over a sidelink connection; and

a physical side uplink control channel corresponding to the physical side uplink shared channel transmission is transmitted or received in a subset of the one or more sets of resource blocks occupied by the physical side uplink shared channel transmission.

2. The method for wireless communications of claim 1, wherein the physical side uplink control channel is transmitted on a lowest subchannel of each set of resource blocks of a corresponding physical side uplink shared channel.

3. The method for wireless communications of claim 1, wherein the physical side uplink control channel is transmitted on a lowest subchannel of a lowest set of resource blocks of a corresponding physical side uplink shared channel.

4. The method for wireless communication of claim 1, wherein the method further comprises:

the user equipment detects a physical-side downlink control channel based on a physical-side downlink control channel location corresponding to a corresponding physical-side downlink shared channel.

5. The method for wireless communication of claim 1, wherein one or more locations of the physical side uplink control channel are determined further based on a channel occupancy time indication.

6. The method for wireless communications according to claim 5, wherein the physical side uplink control channel is for operation within a channel occupancy time, wherein the physical side uplink control channel starts with one set of resource blocks or one subchannel over a plurality of sets of resource blocks of a corresponding physical side uplink shared channel scheduled by a channel occupancy time initiator user equipment.

7. A method for wireless communication, wherein the method comprises:

determining a first starting symbol and a second starting symbol within a time slot for a sidelink transceiver in a wireless network, wherein the sidelink transceiver is a sidelink transceiver on an unlicensed spectrum;

executing a channel access procedure prior to side-uplink transceiving on the unlicensed spectrum; and

when the channel access procedure is successful, a physical side uplink control channel is transmitted or received at the first starting symbol or the second starting symbol within the slot.

8. The method for wireless communication of claim 7, wherein the physical side uplink control channel is transmitted on the first starting symbol within the time slot, and the side uplink transceiving on the first starting symbol further comprises a physical side uplink shared channel transmission.

9. The method for wireless communication of claim 7, wherein the sidelink transceiver on the second starting symbol within the time slot comprises the physical sidelink control channel and a physical sidelink shared channel transmission.

10. The method for wireless communication of claim 7, wherein the sidelink transceiver on the second starting symbol within the time slot comprises only physical sidelink shared channel transmissions.

11. The method for wireless communication of claim 7, wherein the physical side uplink control channel and physical side uplink shared channel transmission on the second starting symbol is a different transport block than a transport block transmitted in a subsequent full slot.

12. The method for wireless communication of claim 7, wherein the physical side uplink control channel and physical side uplink shared channel transmission on the second starting symbol is a repetition of a subset of transport blocks transmitted in a subsequent full time slot.

13. The method for wireless communication of claim 7, wherein the physical side uplink control channel is preconfigured to include a control indicator.

14. The method for wireless communication of claim 13, wherein the control indicator indicates a physical side uplink shared channel in a portion of a time slot in which the channel access procedure is completed.

15. The method for wireless communication of claim 13, wherein the control indicator indicates a physical side uplink shared channel in a partial time slot and a physical side uplink shared channel in a subsequent one of the full time slots completing the channel access procedure.

16. The method for wireless communication of claim 7, wherein at least one start symbol is used for automatic gain control purposes.

17. The method for wireless communications of claim 7, wherein the user equipment monitors each starting symbol within the time slot for physical side uplink control channel detection.

18. The method for wireless communication of claim 7, wherein the user equipment stops monitoring for a subsequent starting symbol in the slot when a previous physical side uplink control channel within the slot is successfully detected.

19. A method for wireless communication, wherein the method comprises:

in a wireless network, establishing, by a user equipment, a sidelink connection over an unlicensed spectrum for sidelink transceiving over the unlicensed spectrum;

performing a type 1 channel access procedure before physical side uplink feedback channel transmission for which no shared channel occupation time is available, and performing one of a type 2A/2B/2C channel access procedure before physical side uplink feedback channel transmission for which shared channel occupation time is available; and

and when the channel access flow is successful, the physical side uplink feedback channel is sent.

20. The method for wireless communication of claim 19, wherein a channel access priority value of the type 1 channel access procedure is configured to be 1.

21. A user equipment for wireless communication, comprising:

a processor, which when executing program instructions stored in a memory, performs the method for wireless communication of any of claims 1-20.

22. A memory storing program instructions that, when executed by a processor, cause the processor to perform the method for wireless communication of any of claims 1-20.