User equipments, and communication methods

Abstract

A method performed by a user equipment (UE) is described. The method includes receiving an uplink and downlink TDD configuration, the uplink and downlink TDD configuration providing a number of slots with only uplink symbols, a number of uplink symbols; determining a number of sidelink (ST) slots at least by using the number of slots, the number of uplink symbols, and a symbol index; generating a bit sequence to indicate the determined number of ST slots; and transmitting, to another UE, an PSBCH, the PSBCH including the generated bit sequence, wherein, for operation with shared spectrum channel access, a SL BWP configuration includes a first parameter and a second parameter, the first parameter indicates a first starting symbol used for SL within a slot, the second parameter indicates a second starting symbol used for SL within a slot, and the symbol index is set to a symbol index of the first starting symbol.

Description

[DESCRIPTION][Title of Invention]USER EQUIPMENTS, AND COMMUNICATION METHODS[Technical Field]

[0001] The present disclosure relates to a user equipment, and a communication method.[Background Art]

[0002] At present, as a radio access system and a radio network technology aimed for the fifth-generation cellular system, technical investigation and standard development are being conducted, as extended standards of Long Term Evolution (LTE), on LTE-Advanced Pro (LTE-A Pro) and New Radio technology (NR) in The Third Generation Partnership Project (3GPP).

[0003] In the fifth-generation cellular system, three services of enhanced Mobile BroadBand (eMBB) to achieve high-speed and large-volume transmission, UltraReliable and Low Latency Communication (URLLC) to achieve low-latency and high- reliability communication, and massive Machine Type Communication (mMTC) to allow connection of a large number of machine type devices such as Internet of Things (loT) have been demanded as assumed scenarios.

[0004] For example, wireless communication devices may communicate with one or more device. For sidelink communication, two communication devices can communicate with each other via PC5 interface. However, given the existing sidelink communication methods cannot directly applied to unlicensed spectrum, the flexibility and / or the efficiency of the whole sidelink communication system would be limited. As illustrated by this discussion, systems and methods according to the present invention, supporting sidelink communication over unlicensed spectrum, which may improve the communication flexibility and / or efficiency, would be beneficial.[Brief Description of the Drawings]

[0005] Figure 1 is a block diagram illustrating one configuration of one or more base stations and one or more user equipments (UEs) in which systems and methods for generation of bit sequence in PSBCH to indicate SL slots may be implemented;

[0006] Figure 2 is a diagram illustrating one example 200 of a resource grid;

[0007] Figure 3 is a diagram illustrating one example 300 of common resource block grid, carrier configuration and BWP configuration by a UE 102 and a base station 160;

[0008] Figure 4 is a diagram illustrating one 400 example of CORESET configuration in a BWP by a UE 102 and a base station 160;

[0009] Figure 5 is a diagram illustrating one example 500 of interlaced transmission and reception in a BWP;

[0010] Figure 6 is a diagram illustrating one example 600 of a SL BWP and a resource pool within the SL BWP;

[0011] Figure 7 is a diagram illustrating one implementation of a method 700 for determination of slots which may belong to a resource pool by a UE 102;

[0012] Figure 8 is a diagram illustrating one implementation of a method 800 for generating a bit sequence to indicate SL slots in PSBCH by a UE 102;

[0013] Figure 9 is a diagram illustrating one example 900 of generating a bit sequence to indicate SL slots in PSBCH by a UE 102;

[0014] Figure 10 illustrates various components that may be utilized in a UE;

[0015] Figure 11 illustrates various components that may be utilized in a base station;[Description of Embodiments]

[0016] A user equipment (UE) is described. The UE includes reception unit configured to receive an uplink and downlink TDD configuration, the uplink and downlink TDD configuration providing a number of slots with only uplink symbols, a number of uplink symbols; a control circuitry configured to determine a number of sidelink (SL) slots at least by using the number of slots, the number of uplink symbols, and a symbol index, and to generate a bit sequence to indicate the determined number of SL slots; and a transmission circuitry configured to transmit, to another UE, an PSBCH, the PSBCH including the generated bit sequence, wherein, for operation with shared spectrum channel access, a SL BWP configuration includes a first parameter and a second parameter, the first parameter indicates a first starting symbol used for SL within a slot, the second parameter indicates a second starting symbol used for SL within a slot, and the symbol index is set to a symbol index of the first starting symbol.

[0017] A communication method performed by a user equipment (UE) is described. The method includes receiving an uplink and downlink TDD configuration, the uplinkand downlink TDD configuration providing a number of slots with only uplink symbols, a number of uplink symbols; determining a number of sidelink (SL) slots at least by using the number of slots, the number of uplink symbols, and a symbol index; generating a bit sequence to indicate the determined number of SL slots; and transmitting, to another UE, an PSBCH, the PSBCH including the generated bit sequence, wherein, for operation with shared spectrum channel access, a SL BWP configuration includes a first parameter and a second parameter, the first parameter indicates a first starting symbol used for SL within a slot, the second parameter indicates a second starting symbol used for SL within a slot, and the symbol index is set to a symbol index of the first starting symbol.

[0018] 3GPP Long Term Evolution (LTE) is the name given to a project to improve the Universal Mobile Telecommunications System (UMTS) mobile phone or device standard to cope with future requirements. In one aspect, UMTS has been modified to provide support and specification for the Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN). 3GPP NR (New Radio) is the name given to a project to improve the LTE mobile phone or device standard to cope with future requirements. In one aspect, LTE has been modified to provide support and specification (TS 38.331, 38.321, 38.300, 37.340, 38.211, 38.212, 38.213, 38.214, etc.) for the New Radio Access (NR) and Next generation - Radio Access Network (NG-RAN).

[0019] At least some aspects of the systems and methods disclosed herein may be described in relation to the 3GPP LTE, LTE-Advanced (LTE-A), LTE-Advanced Pro, New Radio Access (NR), and other 3G / 4G / 5G standards (e.g., 3GPP Releases 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, and / or 18, and / or Narrow Band-Internet of Things (NB-IoT)). However, the scope of the present disclosure should not be limited in this regard. At least some aspects of the systems and methods disclosed herein may be utilized in other types of wireless communication systems.

[0020] A wireless communication device may be an electronic device used to communicate voice and / or data to a base station, which in turn may communicate with a network of devices (e.g., public switched telephone network (PSTN), the Internet, etc.). In describing systems and methods herein, a wireless communication device may alternatively be referred to as a mobile station, a UE (User Equipment), an access terminal, a subscriber station, a mobile terminal, a remote station, a user terminal, aterminal, a subscriber unit, a mobile device, a relay node, etc. Examples of wireless communication devices include cellular phones, smart phones, personal digital assistants (PDAs), laptop computers, netbooks, e-readers, wireless modems, industrial wireless sensors, video surveillance, wearables, vehicles, roadside units, infrastructure devices, etc. In 3GPP specifications, a wireless communication device is typically referred to as a UE. However, as the scope of the present disclosure should not be limited to the 3GPP standards, the terms “UE” and “wireless communication device” may be used interchangeably herein to mean the more general term “wireless communication device”.

[0021] In 3 GPP specifications, a base station is typically referred to as a gNB, a Node B, an eNB, a home enhanced or evolved Node B (HeNB) or some other similar terminology. As the scope of the disclosure should not be limited to 3GPP standards, the terms “base station,”, “gNB”, “Node B,” “eNB,” and “HeNB” may be used interchangeably herein to mean the more general term “base station.” Furthermore, one example of a “base station” is an access point. An access point may be an electronic device that provides access to a network (e.g., Local Area Network (LAN), the Internet, etc.) for wireless communication devices. The term “communication device” may be used to denote both a wireless communication device and / or a base station.

[0022] It should be noted that as used herein, a “cell” may be any communication channel that is specified by standardization or regulatory bodies to be used for International Mobile Telecommunications-Advanced (IMT-Advanced), IMT-2020 (5G) and all of it or a subset of it may be adopted by 3GPP as licensed bands (e.g., frequency bands) to be used for communication between a base station and a UE. It should also be noted that in NR, NG-RAN, E-UTRA and E-UTRAN overall description, as used herein, a “cell” may be defined as “combination of downlink and optionally uplink resources.” The linking between the carrier frequency of the downlink resources and the carrier frequency of the uplink resources may be indicated in the system information transmitted on the downlink resources.

[0023] “Configured cells” are those cells of which the UE is aware and is allowed by a base station to transmit or receive information. “Configured cell(s)” may be serving cell(s). The UE may receive system information and perform the required measurements on configured cells. “Configured cell(s)” for a radio connection may consist of a primary cell and / or no, one, or more secondary cell(s). “Activated cells”are those configured cells on which the UE is transmitting and receiving. That is, activated cells are those cells for which the UE monitors the physical downlink control channel (PDCCH) and in the case of a downlink transmission, those cells for which the UE decodes a physical downlink shared channel (PDSCH). “Deactivated cells” are those configured cells that the UE is not monitoring the transmission PDCCH. It should be noted that a “cell” may be described in terms of differing dimensions. For example, a “cell” may have temporal, spatial (e.g., geographical) and frequency characteristics.

[0024] The base stations may be connected by the NG interface to the 5G - core network (5G-CN). 5G-CN may be called as to NextGen core (NGC), or 5G core (5GC). The base stations may also be connected by the SI interface to the evolved packet core (EPC). For instance, the base stations may be connected to a NextGen (NG) mobility management function by the NG-2 interface and to the NG core User Plane (UP) functions by the NG-3 interface. The NG interface supports a many-to-many relation between NG mobility management functions, NG core UP functions and the base stations. The NG-2 interface is the NG interface for the control plane and the NG-3 interface is the NG interface for the user plane. For instance, for EPC connection, the base stations may be connected to a mobility management entity (MME) by the Sl- MME interface and to the serving gateway (S-GW) by the Sl-U interface. The SI interface supports a many-to-many relation between MMEs, serving gateways and the base stations. The SI -MME interface is the SI interface for the control plane and the S 1 -U interface is the S 1 interface for the user plane. The Uu interface is a radio interface between the UE and the base station for the radio protocol.

[0025] The radio protocol architecture may include the user plane and the control plane. The user plane protocol stack may include packet data convergence protocol (PDCP), radio link control (RLC), medium access control (MAC) and physical (PHY) layers. A DRB (Data Radio Bearer) is a radio bearer that carries user data (as opposed to control plane signaling). For example, a DRB may be mapped to the user plane protocol stack. The PDCP, RLC, MAC and PHY sublayers (terminated at the base station 460a on the network) may perform functions (e.g., header compression, ciphering, scheduling, ARQ and HARQ) for the user plane. PDCP entities are located in the PDCP sublayer. RLC entities may be located in the RLC sublayer. MAC entities may be located in the MAC sublayer. The PHY entities may be located in the PHY sublayer.

[0026] The control plane may include a control plane protocol stack. The PDCP sublayer (terminated in base station on the network side) may perform functions (e.g., ciphering and integrity protection) for the control plane. The RLC and MAC sublayers (terminated in base station on the network side) may perform the same functions as for the user plane. The Radio Resource Control (RRC) (terminated in base station on the network side) may perform the following functions. The RRC may perform broadcast functions, paging, RRC connection management, radio bearer (RB) control, mobility functions, UE measurement reporting and control. The Non-Access Stratum (NAS) control protocol (terminated in MME on the network side) may perform, among other things, evolved packet system (EPS) bearer management, authentication, evolved packet system connection management (ECM)-IDLE mobility handling, paging origination in ECM-IDLE and security control.

[0027] Signaling Radio Bearers (SRBs) are Radio Bearers (RB) that may be used only for the transmission of RRC and NAS messages. Three SRBs may be defined. SRBO may be used for RRC messages using the common control channel (CCCH) logical channel. SRB1 may be used for RRC messages (which may include a piggybacked NAS message) as well as for NAS messages prior to the establishment of SRB2, all using the dedicated control channel (DCCH) logical channel. SRB2 may be used for RRC messages which include logged measurement information as well as for NAS messages, all using the DCCH logical channel. SRB2 has a lower priority than SRB1 and may be configured by a network (e.g., base station) after security activation. A broadcast control channel (BCCH) logical channel may be used for broadcasting system information. Some of BCCH logical channel may convey system information which may be sent from the network to the UE via BCH (Broadcast Channel) transport channel. BCH may be sent on a physical broadcast channel (PBCH). Some of BCCH logical channel may convey system information which may be sent from the network to the UE via DL-SCH (Downlink Shared Channel) transport channel. Paging may be provided by using paging control channel (PCCH) logical channel.

[0028] System information may be divided into the Master Informations lock (MIB) and a number of SystemlnformationBlocks (SIBs).

[0029] The UE may receive one or more RRC messages from the base station to obtain RRC configurations or parameters. The RRC layer of the UE may configure RRC layer and / or lower layers (e.g., PHY layer, MAC layer, RLC layer, PDCP layer)of the UE according to the RRC configurations or parameters which may be configured by the RRC messages, broadcasted system information, and so on. The base station may transmit one or more RRC messages to the UE to cause the UE to configure RRC layer and / or lower layers of the UE according to the RRC configurations or parameters which may be configured by the RRC messages, broadcasted system information, and so on.

[0030] The size of various fields in the time domain is expressed in time units 4096. The constant,f = rs / rc= 642048.

[0031] Multiple OFDM numerologies are supported as given by Table 4.2-1 of [TS 38.211] where p and the cyclic prefix for a bandwidth part are obtained from the higher- layer parameter subcarrierSpacing and cyclicPrefix, respectively.

[0032] The size of various fields in the time domain may be expressed as a number of time units Tc=l / (15000x2048) seconds. Downlink and uplink transmissions are organized into frames with■ Tc= 10ms duration, each consisting of ten subframes of TSf — (A^^A^ / 1000) • Tc= 1ms duration. The number of consecutive OFDM symbols per subframe is ^sym^ame^=^symb^s^ot^rame'11' Each frame is divided into two equally-sized halfframes of five subframes each with half-frame 0 consisting of subframes 0 -4 and halfframe 1 consisting of subframes 5 - 9.

[0033] For subcarrier spacing (SCS) configuration p, slots are numberedE {0, ... , N^ob / rame'lJ' — 1} in increasing order within a subframe and— 1} in increasing order within a frame.number of slots per subframe for subcarrier spacing configuration p. There areconsecutive OFDM symbols in a slot wheredepends on the cyclic prefix as given by Tables 4.3.2-1 and 4.3.2-2 of [TS 38.211]. The start of slot rd1in a subframe is aligned in time with the start of OFDM symbolin the same subframe. Subcarrier spacing refers to a spacing (or frequency bandwidth) between two consecutive subcarriers in the frequency domain. For example, the subcarrier spacing can be set to 15kHz (i.e., / z=0), 30kHz (i.e. p=V), 60kHz (i.e. p=2), 120kHz (i.e. p=3), or 240kHz (i.e. p=4). A resource block is defined as a number of consecutive subcarriers (e.g., 12) in thefrequency domain. For a carrier with different frequency, the applicable subcarrier may be different. For example, for a carrier in a frequency rang 1, a subcarrier spacing only among a set of {15kHz, 30kHz, 60kHz} is applicable. For a carrier in a frequency rang 2, a subcarrier spacing only among a set of {60kHz, 120kHz, 240kHz} is applicable. The base station may not configure an inapplicable subcarrier spacing for a carrier.

[0034] OFDM symbols in a slot can be classified as 'downlink', 'flexible', or 'uplink'. Signaling of slot formats is described in subclause 11.1 of [TS 38.213],

[0035] In a slot in a downlink frame, the UE may assume that downlink transmissions only occur in 'downlink' or 'flexible' symbols. In a slot in an uplink frame, the UE may only transmit in 'uplink' or 'flexible' symbols.

[0036] Various examples of the systems and methods disclosed herein are now described with reference to the Figures, where like reference numbers may indicate functionally similar elements. The systems and methods as generally described and illustrated in the Figures herein could be arranged and designed in a wide variety of different implementations. Thus, the following more detailed description of several implementations, as represented in the Figures, is not intended to limit scope, as claimed, but is merely representative of the systems and methods.

[0037] Figure 1 is a block diagram illustrating one configuration of one or more base stations 160 (e.g., eNB, gNB) and one or more user equipments (UEs) 102 in which systems and methods for generation of bit sequence in PSBCH to indicate SL slots may be implemented. The one or more UEs 102 may communicate with one or more base stations 160 using one or more antennas 122a-n. For example, a UE 102 transmits electromagnetic signals to the base station 160 and receives electromagnetic signals from the base station 160 using the one or more antennas 122a-n. The base station 160 communicates with the UE 102 using one or more antennas 180a-n. Additionally, one or more UEs 102 may communicate with one or more UEs 102 using one or more antennas 122a-n. For example, a UE 102 transmits electromagnetic signals to another UE(s) 102 and receives electromagnetic signals from another UE(s) 102 using the one or more antennas 122a— n. That is, one or more UEs communicate with each other via sidelink communication.

[0038] The UEs 102 may directly communicate with each other by using the sidelink communication. For illustration, UE(s) 102 capable of sidelink communication include a UE 1A, a UE IB and a UE 1C. The UE lAmay be located within the coverageof the base station 160. The UE IB and the UE 1C may be located outside the coverage of the base station 160. The UE 1A and the base station 160 may communicate with each other via downlink and uplink communication. In addition, the UE 1 A and the UE IB may directly communicate with each other via sidelink communication. In addition, the UE IB and the UE 1C may directly communicate with each other via sidelink communication.

[0039] It should be noted that in some configurations, one or more of the UEs 102 described herein may be implemented in a single device. For example, multiple UEs 102 may be combined into a single device in some implementations. Additionally or alternatively, in some configurations, one or more of the base stations 160 described herein may be implemented in a single device. For example, multiple base stations 160 may be combined into a single device in some implementations. In the context of Figure 1, for instance, a single device may include one or more UEs 102 in accordance with the systems and methods described herein. Additionally or alternatively, one or more base stations 160 in accordance with the systems and methods described herein may be implemented as a single device or multiple devices.

[0040] The UE 102 and the base station 160 may use one or more channels 119, 121 to communicate with each other. For example, a UE 102 may transmit information or data to the base station 160 using one or more uplink (UL) channels 121 and signals. Examples of uplink channels 121 include a physical uplink control channel (PUCCH) and a physical uplink shared channel (PUSCH), etc. Examples of uplink signals include a demodulation reference signal (DMRS) and a sounding reference signal (SRS), etc. The one or more base stations 160 may also transmit information or data to the one or more UEs 102 using one or more downlink (DL) channels 119 and signals, for instance. Examples of downlink channels 119 include a PDCCH, a PDSCH, etc. A PDCCH can be used to schedule DL transmissions on PDSCH and UL transmissions on PUSCH, where the Downlink Control Information (DCI) on PDCCH includes downlink assignment and uplink scheduling grants. A PDCCH can be also used for scheduling of sidelink transmissions on PSCCH and PSSCH in one cell, where the Downlink Control Information (DCI) on PDCCH includes sidelink scheduling grants. The PDCCH is used for transmitting Downlink Control Information (DCI) in a case of downlink radio communication (radio communication from the base station to the UE). Here, one or more DCIs (may be referred to as DCI formats) are defined for transmission ofdownlink control information. Information bits are mapped to one or more fields defined in a DCI format. Examples of downlink signals include a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a cell-specific reference signal (CRS), a non-zero power channel state information reference signal (NZP CSI-RS), and a zero-power channel state information reference signal (ZP CSI- RS), etc. Other kinds of channels or signals may be used.

[0041] For the UE(s) 102 capable of sidelink communication, the UEs 102 may use one or more sidelink channels 123 to communicate with each other. For example, a UE 102 may transmit information or data to another UE 102 using one or more sidelink (SL) channels 123 and signals. Examples of sidelink channels 123 include a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), a physical sidelink feedback channel (PSFCH), and a physical sidelink broadcast channel (PSBCH). Examples of sidelink signals include a demodulation reference signal (DMRS), a phase-tracking reference signal (PT-RS), a channel-state information reference signal (CSI-RS), a sidelink primary synchronization signal (S-PSS), and a sidelink secondary synchronization signal (S-SSS).

[0042] Each of the one or more UEs 102 may include one or more transceivers 118, one or more demodulators 114, one or more decoders 108, one or more encoders 150, one or more modulators 154, one or more data buffers 104 and one or more UE operations modules 124. For example, one or more reception and / or transmission paths may be implemented in the UE 102. For convenience, only a single transceiver 118, decoder 108, demodulator 114, encoder 150 and modulator 154 are illustrated in the UE 102, though multiple parallel elements (e.g., transceivers 118, decoders 108, demodulators 114, encoders 150 and modulators 154) may be implemented.

[0043] The transceiver 118 may include one or more receivers (reception units) 120 and one or more transmitters (transmission units) 158. The one or more receivers 120 may receive signals (e.g., downlink channels, downlink signals, sidelink channels, sidelink signals) from the base station 160 or from another UE 102 using one or more antennas 122a-n. For example, the receiver 120 may receive and downconvert signals to produce one or more received signals 116. The one or more received signals 116 may be provided to a demodulator 114. The one or more transmitters 158 may transmit signals (e.g., uplink channels, uplink signals, sidelink channels, sidelink signals) to the base station 160 or to another UE 102 using one or more antennas 122a-n. For example,the one or more transmitters 158 may upconvert and transmit one or more modulated signals 156.

[0044] The demodulator 114 may demodulate the one or more received signals 116 to produce one or more demodulated signals 112. The one or more demodulated signals 112 may be provided to the decoder 108. The UE 102 may use the decoder 108 to decode signals. The decoder 108 may produce one or more decoded signals 106, 110. For example, a first UE-decoded signal 106 may comprise received payload data, which may be stored in a data buffer 104. A second UE-decoded signal 110 may comprise overhead data and / or control data. For example, the second UE-decoded signal 110 may provide data that may be used by the UE operations module 124 to perform one or more operations.

[0045] As used herein, the term “module” may mean that a particular element or component may be implemented in hardware, software or a combination of hardware and software. Elowever, it should be noted that any element denoted as a “module” herein may alternatively be implemented in hardware. For example, the UE operations module 124 may be implemented in hardware, software or a combination of both.

[0046] In general, the UE operations module 124 may enable the UE 102 to communicate with the one or more base stations 160. For a UE capable of sidelink communication, the UE operations module 124 may enable the UE 102 to communicate with the one or more other UE. The UE operations module 124 may include a UE RRC information configuration module 126. For a UE capable of sidelink communication, the UE operations module 124 may include a UE sidelink (SL) control module (unit) 128. In some implementations, the UE operations module 124 may include physical (PHY) entities, Medium Access Control (MAC) entities, Radio Link Control (RLC) entities, packet data convergence protocol (PDCP) entities, and a Radio Resource Control (RRC) entity. For example, the UE RRC information configuration module 126 may process RRC parameter for random access configurations, initial UL BWP configuration, maximum bandwidth the UE can support, and cell specific PUCCH resource configuration(s).

[0047] For a UE capable of sidelink transmission, the UE RRC information configuration module 126 may process parameters included in the (pre-)configuration(s) related to sidelink communications. The UE RRC information configuration module 126 may include a memory unit to store the (pre-)configuration(s)related to sidelink communications. For example, the UE RRC information configuration module 126 may, based on the parameters, determine a SL BWP, one or more resource pools within the SL BWP in frequency domain and time domain for SL communications. The UE RRC information configuration module 126 may provide information related to SL BWP configuration and resource pool configuration to the UE SL control module 128. The UE SL control module 128 may set the SL BWP configuration and the resource pool configuration.

[0048] The UE SL control module 128 may determine the frequency resources, the time resources, the code resources, and / or numerologies for transmission or reception of the PSCCH, the PSSCH, S-SS / PSBCH and / or the PSFCH. The frequency resources for transmission or reception of the PSCCH, the PSSCH and the PSFCH include information related to assigned sub-channel(s) (or interlace(s)) and RB set(s).

[0049] The UE SL control module 128 may determine whether a slot is available for a SL resource pool based on whether at least of one symbol of a symbol duration within a slot is not set as uplink symbol. The determination of the symbol duration is performed by the UE SL control module 128 based on: for operation without shared spectrum channel access, the starting symbol index of the symbol duration is set to a symbol index of a third symbol; for operation with shared spectrum channel access, the starting symbol index of the symbol duration is set to a symbol index of a first symbol.

[0050] The UE SL control module 128 may determine a number of SL slots at least by using a number of slots with only uplink symbols, a number of uplink symbols and a symbol index. The number of slots and the number of uplink symbols are provided by an uplink and downlink TDD configuration. The determination of the symbol index is performed by the UE SL control module 128 based on: for operation without shared spectrum channel access, the symbol index is set to a symbol index of a third symbol; for operation with shared spectrum channel access, the symbol index is set to a symbol index of a first symbol.

[0051] The UE operations module 124 may provide information 148 to the one or more receivers 120. For example, the UE operations module 124 may inform the receiver(s) 120 when or when not to receive transmissions based on the Radio Resource Control (RRC) message (e.g., broadcasted system information, RRC reconfiguration message), MAC control element, SCI (Sidelink Control Information) and / or the DCI (Downlink Control Information). The UE operations module 124 may provideinformation 148, including the PDCCH monitoring occasions, DCI format size, PSCCH monitoring occasions and SCI format size, to the one or more receivers 120. The UE operation module 124 may inform the receiver(s) 120 when or where to receive / monitor the PDCCH candidate for DCI formats and / or the PSCCH candidate for SCI formats. DCI formats can be used at least for scheduling of SL transmission(s) (PSCCH and / or PSSCH transmission(s)) in one cell and / or for scheduling of PUSCH and / or PDSCH in one cell.

[0052] The UE operations module 124 may provide information 138 to the demodulator 114. For example, the UE operations module 124 may inform the demodulator 114 of a modulation pattern anticipated for transmissions from the base station 160.

[0053] The UE operations module 124 may provide information 136 to the decoder 108. For example, the UE operations module 124 may inform the decoder 108 of an anticipated encoding for transmissions from the base station 160. For example, the UE operations module 124 may inform the decoder 108 of an anticipated PDCCH candidate encoding with which DCI size for transmissions from the base station 160. The UE operations module 124 may inform the decoder 108 of an anticipated PSCCH candidate encoding with which SCI size for transmissions from another UE 102.

[0054] The UE operations module 124 may provide information 142 to the encoder 150. The information 142 may include data to be encoded and / or instructions for encoding. For example, the UE operations module 124 may instruct the encoder 150 to encode transmission data 146 and / or other information 142.

[0055] The encoder 150 may encode transmission data 146 and / or other information 142 provided by the UE operations module 124. For example, encoding the data 146 and / or other information 142 may involve error detection and / or correction coding, mapping data to space, time and / or frequency resources for transmission, multiplexing, etc. The encoder 150 may provide encoded data 152 to the modulator 154.

[0056] The UE operations module 124 may provide information 144 to the modulator 154. For example, the UE operations module 124 may inform the modulator 154 of a modulation type (e.g., constellation mapping) to be used for transmissions to the base station 160. The modulator 154 may modulate the encoded data 152 to provide one or more modulated signals 156 to the one or more transmitters 158.

[0057] The UE operations module 124 may provide information 140 to the one or more transmitters 158. This information 140 may include instructions for the one or more transmitters 158. For example, the UE operations module 124 may instruct the one or more transmitters 158 when to transmit a signal to the base station 160 or another UE 102. The one or more transmitters 158 may upconvert and transmit the modulated signal(s) 156 to one or more base stations 160 or another one or more UEs 102.

[0058] The base station 160 may include one or more transceivers 176, one or more demodulators 172, one or more decoders 166, one or more encoders 109, one or more modulators 113, one or more data buffers 162 and one or more base station operations modules 182. For example, one or more reception and / or transmission paths may be implemented in a base station 160. For convenience, only a single transceiver 176, decoder 166, demodulator 172, encoder 109 and modulator 113 are illustrated in the base station 160, though multiple parallel elements (e.g., transceivers 176, decoders 166, demodulators 172, encoders 109 and modulators 113) may be implemented.

[0059] The transceiver 176 may include one or more receivers (reception units) 178 and one or more transmitters (transmission units) 117. The one or more receivers 178 may receive signals (e.g., uplink channels, uplink signals) from the UE 102 using one or more antennas 180a-n. For example, the receiver 178 may receive and downconvert signals to produce one or more received signals 174. The one or more received signals 174 may be provided to a demodulator 172. The one or more transmitters 117 may transmit signals (e.g., downlink channels, downlink signals) to the UE 102 using one or more antennas 180a-n. For example, the one or more transmitters 117 may upconvert and transmit one or more modulated signals 115.

[0060] The demodulator 172 may demodulate the one or more received signals 174 to produce one or more demodulated signals 170. The one or more demodulated signals 170 may be provided to the decoder 166. The base station 160 may use the decoder 166 to decode signals. The decoder 166 may produce one or more decoded signals 164, 168. For example, a first base station-decoded signal 164 may comprise received payload data, which may be stored in a data buffer 162. A second base station-decoded signal 168 may comprise overhead data and / or control data. For example, the second base station-decoded signal 168 may provide data (e.g., PUSCH transmission data) that may be used by the base station operations module 182 to perform one or more operations.

[0061] In general, the base station operations module 182 may enable the base station 160 to communicate with the one or more UEs 102. For a base station capable of sidelink communication, the UE operations module 124 may enable the base station 160 to communicate with the one or more UEs 102 capable of sidelink communication. The base station operations module 182 may include a base station RRC information configuration module 194. For a base station capable of sidelink communication, the base station operations module 182 may include a base station sidelink (SL) control module 196 (or a base station SL processing module 196). The base station operations module 182 may include PHY entities, MAC entities, RLC entities, PDCP entities, and an RRC entity.

[0062] For a base station capable of sidelink transmission, the base station SL control module 196 may determine, for respective UE, the time and frequency resources for scheduling PSCCH and PSSCH and input the information to the base station RRC information configuration module 194.

[0063] The base station operations module 182 may provide the benefit of performing PDCCH candidate search and monitoring efficiently. The base station operations module 182 may provide information 190 to the one or more receivers 178. For example, the base station operations module 182 may inform the receiver(s) 178 when or when not to receive transmissions based on the RRC message (e.g., broadcasted system information, RRC reconfiguration message), MAC control element, and / or the DCI (Downlink Control Information).

[0064] The base station operations module 182 may provide information 188 to the demodulator 172. For example, the base station operations module 182 may inform the demodulator 172 of a modulation pattern anticipated for transmissions from the UE(s) 102.

[0065] The base station operations module 182 may provide information 186 to the decoder 166. For example, the base station operations module 182 may inform the decoder 166 of an anticipated encoding for transmissions from the UE(s) 102.

[0066] The base station operations module 182 may provide information 101 to the encoder 109. The information 101 may include data to be encoded and / or instructions for encoding. For example, the base station operations module 182 may instruct the encoder 109 to encode transmission data 105 and / or other information 101.

[0067] In general, the base station operations module 182 may enable the base station 160 to communicate with one or more network nodes (e.g., a NG mobility management function, a NG core UP functions, a mobility management entity (MME), serving gateway (S-GW), gNBs). The base station operations module 182 may also generate a RRC reconfiguration message to be signaled to the UE 102.

[0068] The encoder 109 may encode transmission data 105 and / or other information 101 provided by the base station operations module 182. For example, encoding the data 105 and / or other information 101 may involve error detection and / or correction coding, mapping data to space, time and / or frequency resources for transmission, multiplexing, etc. The encoder 109 may provide encoded data 111 to the modulator 113. The transmission data 105 may include network data to be relayed to the UE 102.

[0069] The base station operations module 182 may provide information 103 to the modulator 113. This information 103 may include instructions for the modulator 113. For example, the base station operations module 182 may inform the modulator 113 of a modulation type (e.g., constellation mapping) to be used for transmissions to the UE(s) 102. The modulator 113 may modulate the encoded data 111 to provide one or more modulated signals 115 to the one or more transmitters 117.

[0070] The base station operations module 182 may provide information 192 to the one or more transmitters 117. This information 192 may include instructions for the one or more transmitters 117. For example, the base station operations module 182 may instruct the one or more transmitters 117 when to (or when not to) transmit a signal to the UE(s) 102. The base station operations module 182 may provide information 192, including the PDCCH monitoring occasions and DCI format size, to the one or more transmitters 117. The base station operation module 182 may inform the transmitter(s) 117 when or where to transmit the PDCCH candidate for DCI formats with which DCI size. The one or more transmitters 117 may upconvert and transmit the modulated signal(s) 115 to one or more UEs 102.

[0071] It should be noted that one or more of the elements or parts thereof included in the base station(s) 160 and UE(s) 102 may be implemented in hardware. For example, one or more of these elements or parts thereof may be implemented as a chip, circuitry or hardware components, etc. It should also be noted that one or more of the functions or methods described herein may be implemented in and / or performed using hardware.For example, one or more of the methods described herein may be implemented in and / or realized using a chipset, an application-specific integrated circuit (ASIC), a large-scale integrated circuit (LSI) or integrated circuit, etc.

[0072] Abase station may generate a RRC message including the one or more RRC parameters and may transmit the RRC message to a UE. A UE may receive, from a base station, a RRC message including one or more RRC parameters. In the present disclosure, the terms ‘RRC parameter(s)’, ‘RRC information element(s)’, ‘higher layer parameter(s)’ can be used interchangeably. In the present disclosure, higher layer may refer to a layer upper than the physical layer (i.e., Layer 1), for example, MAC layer, RLC layer, PDCP layer, SDAP layer, RRC layer, and / or application layer.

[0073] A RRC parameter may further include one or more RRC parameter(s). In the present disclosure, a RRC message may include system information, a RRC message may include one or more RRC parameters. A RRC message may be sent on a broadcast control channel (BCCH) logical channel, a common control channel (CCCH) logical channel or a dedicated control channel (DCCH) logical channel.

[0074] In the present disclosure, a description “a UE is configured with or is provided a parameter” also implies the description “the UE may receive, from the base station, an RRC message (or information) which includes the parameter”. Likewise, the description “a base station configures the UE with or provides the UE the parameter” also implies the description “the base station may transmit, to the UE, an RRC message (or information) which includes the parameter”.

[0075] Figure 2 is a diagram illustrating one example of a resource grid 200.

[0076] For each numerology (i.e., for each SCS u) and carrier, a resource grid of N grids 'ze’pNsJ® subcarriers and NSymbsltb^rame'IJOFDM symbols is defined, starting at common resource block NSnislar,’>iindicated by higher layer signaling. There is one set of resource grids per transmission direction (uplink or downlink) with the subscript x set to DL and UL for downlink and uplink, respectively. There is one resource grid for a given antenna port p, subcarrier spacing configuration p, and the transmission direction (downlink or uplink). When there is no risk for confusion, the subscript x may be dropped.

[0077] In the Figure 2, the resource gird 200 includes the Ngrids '^Nsc1^ (202) subcarriers in the frequency domain and includes Nsymbs'lb^rame41(204) symbols in the time domain. In the Figure 2, as an example for illustration, the subcarrier spacingconfiguration p is set to 0. That is, in the Figure 2, the number of consecutive OFDM symbols Nsyrnf"^''0^^ (204) per subframe is equal to 14.

[0078] The carrier bandwidth TVgrid5^""for subcarrier spacing configuration / / is given by the higher-layer (RRC) parameter carrier Bandwidth in the SCS-SpecificCarrier IE. The starting position Ngnftar,,fJfor subcarrier spacing configuration p is given by the higher-layer parameter offsetToCarrier in the SCS- SpecificCarrier IE. The frequency location of a subcarrier refers to the center frequency of that subcarrier.

[0079] In the Figure 2, for example, a value of offset is provided by the higher-layer parameter offsetToCarrier. That is, k = 12 X offset is the lowest usable subcarrier on this carrier.

[0080] Each element in the resource grid for antenna port p and subcarrier spacing configuration p is called a resource element and is uniquely identified by (k, Z)PiMwhere k is the index in the frequency domain and I refers to the symbols position in the time domain relative to same reference point. The resource element consists of one subcarrier during one OFDM symbol.

[0081] A resource block is defined as A''SCRB=12 consecutive subcarriers in the frequency domain. As shown in the Figure 2, a resource block 206 includes 12 consecutive subcarriers in the frequency domain. Resource block can be classified as common resource block (CRB) and physical resource block (PRB).

[0082] Common resource blocks are numbered from 0 and upwards in the frequency domain for subcarrier spacing configuration p. The center of subcarrier 0 of common resource block with index 0 (i.e. CRB0) for subcarrier spacing configuration p coincides with point A. The relation between the common resource block number nBRBin the frequency domain and resource element (k, Z) for subcarrier spacing configuration p is given by Formula (1) ncR^=floor{k / NscRB') where k is defined relative to the point A such that / c=0 corresponds to the subcarrier centered around the point A. The function floor(A) hereinafter is floor operation to output a maximum integer not larger than the A.

[0083] Point A refers to as a common reference point. Point A coincides with subcarrier 0 (i.e., A=0) of a CRB 0 for all subcarrier spacing. Point A can be obtained from a RRC parameter offsetToPointA or a RRC parameter absoluteFrequencyPointA.The RRC parameter offsetToPointA is used for a PCell downlink and represents the frequency offset between point A and the lowest subcarrier of the lowest resource block, which has the subcarrier spacing provided by a higher-layer parameter subCarrierSpacingCommon and overlaps with the SS / PBCH block used by the UE for initial cell selection, expressed in units of resource blocks assuming 15 kHz subcarrier spacing for frequency range (FR) 1 and 60 kHz subcarrier spacing for frequency range (FR2). FR1 corresponds to a frequency range between 410MHz and 7125MHz. FR2 corresponds to a frequency range between 24250MHz and 52600MHz. The RRC parameter absoluteFrequencyPointA is used for all cased other than the PCell case and represents the frequency-location of point A expressed as in ARFCN. The frequency location of point A can be the lowest subcarrier of the carrier bandwidth ( or the actual carrier). Additionally, point A may be located outside the carrier bandwidth ( or the actual carrier).

[0084] As above mentioned, the information element (IE) SCS-SpecificCarrier provides parameters determining the location and width of the carrier bandwidth or the actual carrier. That is, a carrier (or a carrier bandwidth, or an actual carrier) is determined (identified, or defined) at least by a RRC parameter offsetToCarrier, a RRC parameter subcarrierSpacing, and a RRC parameter carrierBandwidth in the SCS- SpecificCarrier IE.

[0085] The subcarrierSpacing indicates (or defines) a subcarrier spacing of the carrier. The offsetToCarrier indicates an offset in frequency domain between point A and a lowest usable subcarrier on this carrier in number of resource blocks (e.g. CRBs) using the subcarrier spacing defined for the carrier. The carrierBandwidth indicates width of this carrier in number of resource blocks (e.g., CRBs or PRBs) using the subcarrier spacing defined for the carrier. A carrier includes at most 275 resource blocks.

[0086] Physical resource blocks for subcarrier spacing configuration p are defined within a bandwidth part and numbered form 0 to NB wpflze4Jwhere i is the number of the bandwidth part. The relation between the physical resource block npp / T in bandwidth part (BWP) i and the common resource block ncRjf is given by Formula (2) na<F = npRBT + NBWP,is,art' where NBWP,i5tar1’pis the common resource block where bandwidth part i starts relative to common resource block 0 (CRB0). When there is no risk for confusion the index p may be dropped.

[0087] A BWP is a subset of contiguous common resource block for a given subcarrier spacing configuration / / on a given carrier. To be specific, a BWP can be identified (or defined) at least by a subcarrier spacing p indicated by the RRC parameter subcarrierSpacing, a cyclic prefix determined by the RRC parameter cyclicPrefix, a frequency domain location, a bandwidth, an BWP index indicated by bwp-Id and so on. The locationAndBandwidth can be used to indicate the frequency domain location and bandwidth of a BWP. The value indicated by the locationAndBandwidth is interpreted as resource indicator value (RIV) corresponding to an offset (a starting resource block) Restart and a length L RB in terms of contiguously resource blocks. The offset RRstart is a number of CRBs between the lowest CRB of the carrier and the lowest CRB of the BWP. The NBwp,istart^ is given as Formula (3) NBWP.ISTART’A=OCarrier+RBstan. The value of Ocarrier is provided by offsetTocarrier for the corresponding subcarrier spacing configuration p.

[0088] A UE 102 configured to operate in BWPs of a serving cell, is configured by higher layers for the serving cell a set of at most four BWPs in the downlink for reception. At a given time, a single downlink BWP is active. The bases station 160 may not transmit, to the UE 102, PDSCH and / or PDCCH outside the active downlink BWP. A UE 102 configured to operate in BWPs of a serving cell, is configured by higher layers for the serving cell a set of at most four BWPs for transmission. At a given time, a single uplink BWP is active. The UE 102 may not transmit to the base station 160, PUSCH or PUCCH outside the active BWP. The specific signaling (higher layers signaling) for BWP configurations are described later.

[0089] A UE 102, configured to operate in a SL BWP, is configured or preconfigured by higher layers for the serving cell or by a pre-configuration a SL BWP for sidelink reception and / or transmission. At a given time, a single SL BWP is active. The UE 102 may not transmit, to another UE 102, sidelink channel (PSCCH, PSCCH, and / or PSFCH) outside the active SL BWP.

[0090] Figure 3 is a diagram illustrating one example 300 of common resource block grid, carrier configuration and BWP configuration by a UE 102 and a base station 160.

[0091] Point A 301 is the lowest subcarrier of a CRB0 for all subcarrier spacing configurations. The CRB grid 302 and the CRB grid 312 are corresponding to two different subcarrier spacing configurations. The CRB grid 302 is for subcarrier spacingconfiguration p =0 (i.e., the subcarrier spacing with 15kHz). The CRB grid 312 is for subcarrier spacing configuration p =l (i.e., the subcarrier spacing with 30kHz).

[0092] One or more carriers are determined by respective SCS-SpecificCarrier lEs, respectively. In the Figure 3, the carrier 304 uses the subcarrier spacing configuration ^=0. And the carrier 314 uses the subcarrier spacing configuration ^=1. The starting positionof the carrier 304 is given based on the value of an offset 303 (i.e.Ocarrier) indicated by an offsetToCarrier in an SCS-SpecificCarrier IE. As shown in the Figure 3, for example, the offsetToCarrier indicates the value of the offset 303 as Ocamer =3. That is, the starting position 7Vgrid'sZort"uof the carrier 304 corresponds to the CRB3 of the CRB grid 302 for subcarrier spacing configuration p-0. In the meantime, the starting position Nsfftar^‘ of the carrier 314 is given based on the value of an offset 313 (i.e. Ocamer) indicated by an offsetToCarrier in another SCS-SpecificCarrier IE. For example, the offsetToCarrier indicates the value of the offset 313 as Ocarrier =1 . That is, the starting position Iffffart>,iof the carrier 314 corresponds to the CRB1 of the CRB grid 312 for subcarrier spacing configuration p=\ . A carrier using different subcarrier spacing configurations can occupy different frequency ranges.

[0093] As above-mentioned, a BWP is for a given subcarrier spacing configuration p. One or more BWPs can be configured for a same subcarrier spacing configuration p. For example, in the Figure 3, the BWP 306 is identified at least by the p=0, a frequency domain location, a bandwidth (ZRB), and an BWP index (index A). The first PRB (i.e. PRB0) of a BWP is determined at least by the subcarrier spacing of the BWP, an offset derived by the locationAndBandwidth and an offset indicated by the offsetToCarrier corresponding to the subcarrier spacing of the BWP. An offset 305 (Restart) is derived as 1 by the locationAndBandwidth. According to the Formulas (2) and (3), the PRB0 of BWP 306 corresponds to CRB 4 of the CRB grid 302, and the PRB1 of BWP 306 corresponds to CRB 5 of the CRB grid 302, and so on.

[0094] Additionally, in the Figure 3, the BWP 308 is identified at least by the p=0, a frequency domain location, a bandwidth (ZRB), and an BWP index (index B). For example, an offset 307 (Restart) is derived as 6 by the locationAndBandwidth. According to the Formulas (2) and (3), the PRB0 of BWP 308 corresponds to CRB 9 of the CRB grid 302, and the PRB 1 of BWP 308 corresponds to CRB 10 of the CRB grid 302, and so on.

[0095] Additionally, in the Figure 3, the BWP 316 is identified at least by the p=l, a frequency domain location, a bandwidth (ZRB), and an BWP index (index C). For example, an offset 315 (RBstart) is derived as 1 by the locationAndBandwidth. According to the Formulas (2) and (3), the PRBO of BWP 316 corresponds to CRB 2 of the CRB grid 312, and the PRB1 of BWP 316 corresponds to CRB 3 of the CRB grid 312, and so on.

[0096] In the present disclosure, a BWP illustrated in the Figure 3 may refer to a DL BWP, a UL BWP, or a sidelink BWP.

[0097] As shown in the Figure 3, a carrier with the defined subcarrier spacing locate in a corresponding CRB grid with the same subcarrier spacing. A BWP with the defined subcarrier spacing locate in a corresponding CRB grid with the same subcarrier spacing as well.

[0098] A base station may transmit a RRC message including one or more RRC parameters related to BWP configuration to a UE. A UE may receive the RRC message including one or more RRC parameters related to BWP configuration from a base station. For each cell, the base station may configure at least an initial DL BWP, one initial uplink bandwidth parts (initial UL BWP) and one sidelink BWP to the UE. Furthermore, the base station may configure additional UL and DL BWPs to the UE for a cell.

[0099] SIB1, which is a cell-specific system information block (SystemlnformationBlock, SIB), may contain information relevant when evaluating if a UE is allowed to access a cell and define the scheduling of other system information. SIB1 may also contain radio resource configuration information that is common for all UEs, and barring information applied to the unified access control. The RRC parameter ServingCellConfiigCommon is used to configure cell specific parameters of a UE's serving cell. The RRC parameter ServingCellConfig is used to configure (add or modify) the UE with a serving cell, which may be the SpCell or an SCell of an MCG or SCG. The RRC parameter ServingCellConfig herein are mostly UE specific but partly also cell specific.

[0100] The base station may configure the UE with a RRC parameter BWP- Downlink and a RRC parameter BWP-Uplink. The RRC parameter B WP-Downlink can be used to configure an additional DL BWP. The RRC parameter BWP-Uplink can be used to configure an additional UL BWP. The base station may transmit the BWP-Downlink and the BWP-Uplink which may be included in RRC parameter ServingCellConfig to the UE.

[0101] The UE may be configured by the based station, at least one initial BWP and up to 4 additional BWP(s). One of the initial BWP and the configured additional BWP(s) may be activated as an active BWP. The UE may monitor DCI format, and / or receive PDSCH in the active DL BWP. The UE may not monitor DCI format, and / or receive PDSCH in a DL BWP other than the active DL BWP. The UE may transmit PUSCH and / or PUCCH in the active UL BWP. The UE may not transmit PUSCH and / or PUCCH in a BWP other than the active UL BWP.

[0102] As above-mentioned, a UE may monitor DCI format in the active DL BWP. To be more specific, a UE may monitor a set of PDCCH candidates in one or more CORESETs on the active DL BWP on each activated serving cell configured with PDCCH monitoring according to corresponding search space set where monitoring implies decoding each PDCCH candidate according to the monitored DCI formats.

[0103] A set of PDCCH candidates for a UE to monitor is defined in terms of PDCCH search space sets. A search space set can be a CSS set or a USS set. A UE may monitor a set of PDCCH candidates in one or more of the search space sets.

[0104] Figure 4 is a diagram illustrating one 400 example of CORESET configuration in a BWP by a UE 102 and a base station 160.

[0105] Figure 4 illustrates that a UE 102 is configured with three CORESETs for receiving PDCCH transmission in two BWPs. In the Figure 4, 401 represent point A. 402 is an offset in frequency domain between point A 401 and a lowest usable subcarrier on the carrier 403 in number of CRBs, and the offset 402 is given by the offsetToCarrier in the SCS-SpecificCarrier IE. The BWP 405 with index A and the carrier 403 are for a same subcarrier spacing configuration p. The offset 404 between the lowest CRB of the carrier and the lowest CRB of the BWP in number of RBs is given by the locationAndBandwidth included in the BWP configuration for BWP A. The BWP 407 with index B and the carrier 403 are for a same subcarrier spacing configuration p. The offset 406 between the lowest CRB of the carrier and the lowest CRB of the BWP in number of RBs is given by the locationAndBandwidth included in the BWP configuration for BWP B.

[0106] For the BWP 405, two CORESETs are configured. As above-mentioned, a RRC parameter frequencyDomainResource in respective CORESET configurationindicates the frequency domain resource for respective CORESET. In the frequency domain, a CORESET is defined in multiples of RB groups and each RB group consists of 6 RBs. For example, in the Figure 4, the RRCfrequencyDomainResource provides a bit string with a fixed size (e.g., 45 bits) as like ‘ 11010000...000000’ for CORESET#1. That is, the first RB group, the second RB group, and the fourth RB group belong to the frequency domain resource of the CORESET#! . Additionally, the RRC parameter frequencyDomainResource provides a bit string with a fixed size (e.g., 45 bits) as like ‘00101110...000000’ for CORESET#2. That is, the third RB group, the fifth RB group, the sixth RB group and the seventh RB group belong to the frequency domain resource of the CORESET#2.

[0107] For the BWP 407, one CORESET is configured. As above-mentioned, a RRC parameter frequencyDomainResource in the CORESET configuration indicates the frequency domain resource for the CORESET #3. In the frequency domain, a CORESET is defined in multiples of RB groups and each RB group consists of 6 RBs. For example, in the Figure 4, the RRC parameter frequencyDomainResource provides a bit string with a fixed size (e.g., 45 bits) as like ‘ 11010000...000000’ for CORESET#3. That is, the first RB group, the second RB group, and the fourth RB group belong to the frequency domain resource of the CORESET#3. Although the bit string configured for CORESET#3 is same as that for CORESET# 1, the first RB group of the BWP B is different from that of the BWP A in the carrier. Therefore, the frequency domain resource of the CORESET#3 in the carrier is different from that of the CORESET# 1 as well.

[0108] For the communication system, spectrum is divided into licensed spectrum and unlicensed spectrum. The NR technologies have been developed in the licensed spectrum and in the unlicensed spectrum. The operation in unlicensed spectrum, used as a complementary solution, can increase the throughput of the overall wireless communication system. However, operation in unlicensed spectrum is subject to regulatory limitations and restrictions. For example, the European Telecommunications Standards Institute (ETSI) has defined regulations for operation over the unlicensed spectrum. For example, the occupied channel bandwidth (OCB), which is defined as a bandwidth containing 99% of the signal power, should be larger than a percentage of the nominal channel bandwidth (NCB). For example, according to the ETSI regulations, the OCB should be between 70% and 100% of the NCB for 5GHz band.

[0109] An unlicensed band (or a carrier, or a subband) would be divided into one or multiple non-overlapping channels of 20MHz bandwidth in the frequency domain. For a (nominal) channel bandwidth of 20MHz, one transmission should occupy a channel bandwidth larger than what the regulation on OCB requires, for example, one transmission should be larger than 80% of the channel bandwidth of 20MHz to meet the OCB requirement. To meet the OCB requirement, the design of interlaced transmission had been introduced where each interlace transmission within a channel bandwidth can occupy a channel bandwidth being larger than what the OCB requires. [OHO] The unlicensed band (unlicensed spectrum) may be or may be not configured with operation with shared spectrum channel access. Likewise, the licensed band (licensed spectrum) may be or may be not configured with operation with shared spectrum channel access. In the present disclosure, the unlicensed band (the unlicensed spectrum) configured with operation with shared spectrum channel access can be termed the unlicensed band A (the unlicensed spectrum A). The unlicensed band (unlicensed spectrum) not configured with operation with shared spectrum channel access can be termed the unlicensed band B (the unlicensed spectrum B). The licensed band (the licensed spectrum) configured with operation with shared spectrum channel access can be termed the licensed band C (the licensed spectrum C). The licensed band (licensed spectrum) not configured with operation with shared spectrum channel access can be termed the licensed band D (the licensed spectrum D).

[0111] Interlaced transmission (i.e., interlace RB-based transmission) had been introduced to ensure the compliance with the regulations on OCB and NCB requirements. Specifically, the interlaced transmission is designed such that each interlace can occupy the channel bandwidth where the occupied channel bandwidth can fulfill the requirement of the OCB.

[0112] An interlace includes a set of resource blocks that are spread out across the bandwidth of a carrier in the frequency domain. A number of interlaces Mis subject to the value of a SCS. That is, the number of interlaces Mmay be predefined according to a specific SCS. For example, if the SCS is equal to 15kHz, the number of resource block interlaces Mis correspondingly equal to 10. If the SCS is equal to 30kHz, the number of resource block interlaces Mis correspondingly equal to 5.

[0113] Figure 5 is a diagram illustrating one example 500 of interlaced transmission and reception in a BWP.

[0114] In the Figure 5, each block in the frequency domain refers to a common resource block. In the Figure 5, the subcarrier spacing is configured as 30kHz and the number of resource block interlaces M are 5. Then the interlaces are indexed from 0 to Af-1. That is, an interlace m, where m = 0, 1, . . M-l, consists of a plurality of common resource blocks with indexes {m, M+m, 2M+m, 3M+m, ... } . For example, in the Figure 5, the interlace m=0 consists of common resource blocks with indexes {0, 5, 10, 15, the interlace m=l consists of common resource blocks with indexes {1, 6, 11, 16, on.

[0115] In the frequency domain, a BWP 501 is determined as illustrated in Figure 3. An interlaced resource block in the BWP is denoted aswhere theis indexed from 0, 1, ..., in the BWP. The relation between the interlace resource blockniRB mar*d interlace m and the common resource block nRRrsis given by nRRB=The ^BWP^ *s^ecommonresource block where the BWP starts relative to common resource block 0 (i.e., a common resource block with index 0). In the Figure 5, the BWP 501 starts in a CRB with index 4 relative to the CRB with index 0.

[0116] At least for NR-U operation in, for example, 5GHz spectrum, a BWP may have a bandwidth of multiple of 20MHz. A sub-band may comprise 20MHz or a multiple of 20MHz bandwidth. A sub-band may also be referred to as a sub-channel, or a channel access bandwidth (e.g., a channel of 20MHz). Then a BWP may include one or more sub-bands in the frequency domain. A sub-band consists of multiple nonoverlapping RBs. The number of resource blocks within a sub-band may depend on the SCS of the BWP. For example, the sub-band size for SCS=15kHz may be equal to 108 for a 40MHz BWP, and the sub-band size for SCS=30kHz may be equal to 53 for a 40MHz BWP. That is, a sub-band is an RB set of non-overlapping and contiguous (common) resource blocks. And a sub-band can be defined by a starting common RB and an ending common RB in the frequency domain. Hereinafter, an RB set is used to refer to a sub-band. In other words, an RB set consists of non-overlapping resource blocks and can be defined by a starting common RB and an ending common RB.

[0117] As in the Figure 5, the BWP 501 includes two RB sets, i.e., a RB set 502 and a RB set 503. The RB sets within a BWP can be indexed from 0 in an increase order along with the frequency. According to higher layer (RRC) configurations, there maybe a gap 504 between two consecutive RB sets. The gap in unit of resource block can be indicated by the higher layer configurations. Additionally or alternatively, there may be no gap between two RB sets. In other words, there may be a separation of zero, one, or more RBs between two contiguous RB sets within the BWP in the frequency domain.

[0118] In the Figure 5, in the frequency domain, a interlace whose RBs have a lowest CRB index within the first RB set is the interlace m = 4, while the interlace whose RBs have a lowest CRB index within the second RB set is the m = 0.

[0119] In order to ensure a fair co-existence with another NR-U node and / or another radio access technology (RAT) node such as wireless LAN node, the base station 160 and / or the UE 102 may have to perform Listen Before Talk (LBT) procedure before their transmissions. LBT procedure is also referred to as Channel Access procedure. The base station 160 and / or the UE 102 may perform the channel access procedure to determine if there is the presence of other transmission in a channel before their transmission. There may be several types of Channel Access (CA) procedures. For example, Cat-1 LBT is a channel access procedure without channel sensing. Cat-2 LBT is a channel access procedure with one shot channel sensing. Cat-2 LBT may also be referred to as Type-2 channel access procedure. Cat-1 and Cat-2 LBTs may be allowed only inside COT. Cat-3 LBT is a channel access procedure with random backoff with a fixed contention window (CW) size. Cat-4 LBT is a channel access procedure with random backoff with an adaptive CW size. Cat-4 LBT may also be referred to as Type- 1 channel access procedure.

[0120] In a BWP, before a gNB and / or a UE attempt to transmit a signal, the gNB and / or the UE may first perform channel sensing in each RB set to check whether a channel (or one or more RB sets within the BWP allocated for transmission) is available or not for transmission. If the channel or the allocated RB set(s) is sensed to be considered to be idle (i.e., the channel is available for transmission or the gNB and / or the UE gets a channel access successfully), the gNB and / or the UE may transmit on the channel or on the allocated RB set(s). On the other hand, if the channel or the allocated RB set(s) is sensed to be considered to be busy (i.e., the channel is not available or the gNB and / or the UE does not get a channel access successfully), the gNB and / or the UE may not transmit on the channel or on the allocated RB set(s).

[0121] Vehicle-to-everything (V2X) communication technologies have been developed by 3 GPP for the automotive industry. V2X refers to a communicationtechnology through which a vehicle exchanges information with another vehicle, a pedestrian, an object having an infrastructure, and so on. The V2X is divided into 4 types, such as vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), vehicle-to- network (V2N), and vehicle-to-pedestrian (V2P). Therefore, the V2X communication is different from the communication between the UEs and gNBs. The V2X communication enables the communication between the UEs, which is also called as sidelink. That is, sidelink communication supports UE-to-UE direct communication via a PC5 interface. In other words, sidelink communication is directly performed or communicated between one transmitting UE and one or more receiving UEs.

[0122] Sidelink communication consists of unicast, groupcast and broadcast. The unicast may refer to a communication between two UEs, i.e., one transmitting UE and one receiving UE. The groupcast and / or the broadcast may refer to a communication between one transmitting UE and multiple receiving UEs.

[0123] Currently NR Sidelink communication supports two sidelink resource allocation modes, mode 1 and mode 2. The difference between the sidelink resource allocation mode 1 and the sidelink resource allocation mode 2 lies in which determine the resource to be used for the sidelink communication.

[0124] In mode 1, the sidelink resource allocation is provided or determined by the base station and / or the network. That is, for mode 1, the base station may manage the resource allocation for the UEs. For example, a base station may allocate the resources for sidelink communication to an in-coverage UE. In sidelink resource allocation mode 1 , dynamic grant, configured grant type 1 and configured grant type 2 are supported for PSSCH and PSCCH transmission. In sidelink resource allocation mode 1, for sidelink dynamic grant, the PSSCH transmission is scheduled by a DCI format 3_0. For sidelink configured grant type 1, the configured grant is provided (activated) or released (deactivated) by RRC signaling. For sidelink configured grant type 2, the configured grant is provided or released by PDCCH with the DCI format 3_0.

[0125] In mode 2, the sidelink resource allocation is determined by a TX UE itself. The UE may decide the sidelink transmission resources in a resource pool. The UE may carry out the resource allocation without involvement of the base station. These UEs may autonomously determine to select resources for sidelink communication based on a sensing-based procedure.

[0126] In mode 1, the DCI format 3_0 is used by the base station for scheduling of NR PSCCH and NR PSSCH in one cell. The base station may determine the scheduling information of NR PSCCH and NR PSSCH and provide the scheduling information to an in-coverage UE. The scheduling information may at least include a Resource pool index field, a time gap field, a HARQ process number field, a new data indicator field, a Lowest index of the subchannel allocation to the initial transmission field, SCI format 1 -A fields, and so on. The Resource pool index field is used to indicate an index of a resource pool for which the sidelink transmission is scheduled and the SCI format 1-A fields here refer to the frequency resource assignment field and the time resource assignment field. That is, in mode 1, the base station may determine the time and frequency resource assignment for scheduling of sidelink transmission and then generate the corresponding fields of the scheduling information in the DCI format 3_0. A TX UE (an in-coverage UE) that received the DCI format 3_0 may transmit the PSCCH with SCI format 1-A and the PSSCH in the resource assigned by the base station based on the scheduling information in the DCI format 3_0. Moreover, the SCI format 1 -A transmitted by the TX UE includes the frequency resource assignment field and the time resource assignment field which are as same as those included in the DCI format 3_0. ARX UE (an out-coverage UE and / or an in-coverage UE) that received the PSCCH with the SCI format 1-A can receive the PSSCH in the resource assigned by the base station.

[0127] In mode 2, a TX UE may autonomously determine to select resources for sidelink communication and generate the fields in SCI format 1-A to notify an RX UE of the time and frequency resource assignment. The RX UE that received the PSCCH with the SCI format 1 -A can receive the PSSCH in the resource assigned by the TX UE.

[0128] Sidelink communication supports physical channels such as Physical Sidelink Control Channel (PSCCH), Physical Sidelink Shared Channel (PSSCH), Physical Sidelink Feedback Channel (PSFCH), and Physical Sidelink Broadcast Channel (PSBCH).

[0129] The PSCCH is used for transmitting / receiving sidelink control information (e.g., the lst-stage SCI). For example, the PSCCH indicates resource and other transmission parameters used by a UE for PSSCH reception. PSCCH transmission is associated with a DM-RS. For PSCCH, QPSK is supported.

[0130] The PSSCH is used for transmitting / receiving sidelink control information (e.g., the 2nd-stage SCI), transport block(s) of data, and channel state information (CSI). The sidelink control information herein may include information, for example, for HARQ for HARQ procedures and CSI feedback triggers, etc. At least 6 OFDM symbols within a slot are used for PSSCH transmission. PSSCH transmission is associated with a DM-RS and may be associated with a PT-RS. For PSSCH, QPSK, 16QAM, 64QAM and 256QAM are supported.

[0131] Each PSSCH transmission is associated with an PSCCH transmission. A PSCCH transmission carries the 1ststage of the SCI where the 1ststage of the SCI may schedule one or more resources for one or more PSSCH transmissions. That is, the one or more PSSCH transmissions are associated with the PSCCH transmission. In other words, the PSCCH transmission (or the 1ststage of the SCI) may be associated with one or more PSSCH transmissions.

[0132] PSFCH is used for carrying HARQ feedback over the sidelink from a UE which is an intended recipient of a PSSCH transmission to the UE which performed the PSSCH transmission. PSFCH sequence is transmitted in one PRB repeated over two OFDM symbols near the end of the sidelink resource in a slot.

[0133] The PSBCH is used for transmitting broadcast information. PSBCH occupies 9 and 7 symbols for normal and extended CP cases respectively, including the associated DM-RS.

[0134] Sidelink communication supports physical signals such as demodulation reference signal (DM-RS), phase-tracking reference signal (PT-RS), channel-state information reference signal (CSI-RS), sidelink synchronization signals.

[0135] The DMRS(s) are associated with PSCCH, PSSCH and / or PSBCH. A transmitting UE may transmit the DMRS within the associated sidelink physical channel. A receiving UE may use the DMRS to estimate and / or decode the associated sidelink physical channel.

[0136] The PT-RS is used to mitigate the effect of phase noise. A transmitting UE may transmit the PT-RS within the PSSCH transmission. The receiving UE may receive the PT-RS and use the PT-RS to mitigate the effect of phase noise.

[0137] The CSI-RS is used for measuring channel state information. A transmitting UE may transmit sidelink CSI-RS within a unicast PSSCH transmission. A receivingUE may measure the channel state information by using the CSI-RS and transmit a CSI report based on the measurement to the transmitting UE.

[0138] The Sidelink synchronization signal consists of sidelink primary and sidelink secondary synchronization signals (S-PSS, S-SSS), each occupying 2 symbols and 127 subcarriers. The sidelink synchronization signals are transmitted together with the PSBCH in a slot. Specifically, reception occasions of a PSBCH, S-PSS, and S-SSS are in consecutive symbols in a slot and form a S-SS / PSBCH block. For a SL-BWP, the S-SS / PSBCH block has a same SCS as the PSCCH, the PSSCH, and / or the PSFCH.

[0139] In various implementations of the present disclosure, a UE may be provided NR sidelink communication (pre-)configuration(s). For simplicity, (pre-)configuration(s) hereinafter refer to the NR sidelink communication (pre-)configuration(s). (Pre-)configuration(s) in the present disclosure may include configuration(s) received by system information (e.g., SIB 12) from a base station, configuration(s) received by dedicated RRC signaling (e.g., RRC configuration / parameters / message) from a base station, and / or configuration(s) preconfigured in the UE (i.e., pre-configuration). Regarding the pre-configuration, a memory unit of the UE may store the pre-configuration in advance.

[0140] In various examples or implementations of the present disclosure, (pre-)configuration(s) may include configuration(s) of one or more sidelink BWPs for sidelink communication. That is, a UE may receive the configuration(s) of the one or more BWPs included in system information, in dedicated RRC signaling, and / or in a pre-configuration. In the present disclosure, a UE may be provided by the (pre-)configuration(s) a BWP for sidelink transmissions.

[0141] In various examples or implementations of the present disclosure, a SL BWP configuration may include configuration(s) of one or more resource pools for sidelink communication. That is, the configuration(s) of the one or more resource pools (the configuration(s) related to the one or more resource pools) may be received in system information, received in dedicated RRC signaling, and / or preconfigured in a preconfiguration. According to the configuration(s), a resource pool may be indicated to be used either for sidelink communication reception or for sidelink communication transmission. Additionally or alternatively, a resource pool may be indicated to be used for both sidelink communication reception and sidelink communication transmission.Each resource pool is associated with either the sidelink resource allocation Mode 1 or the sidelink resource allocation Mode 2.

[0142] Figure 6 is a diagram illustrating one example 600 of a SL BWP and a resource pool within the SL BWP.

[0143] A UE 102 is provided by a parameter SL-BWP-Config a BWP (a SL BWP) for sidelink transmission with numerology and resource grid. The determination of a SL BWP 601 is similar as how to determine a BWP specified in the Figure 3.

[0144] In the Figure 6, each block in the time domain represents a slot. One resource pool is configured within the SL BWP 601 . The resource pool can be for transmission of PSSCH, PSCCH and / or PSFCH, and / or for reception of PSSCH, PSCCH and / or PSFCH. The first RB of the resource pool relative to the first RB of SL BWP, 602, may be indicated by a parameter included in the (pre-)configurations.

[0145] Not all the slots within the SL BWP may be assigned to a resource pool within the SL BWP. That is, not all the slots may belong to a resource pool. A slot assigned to a resource pool (or a slot belongs to a resource pool) can be also referred to a slot available for the resource pool. On the contrary, a slot not assigned to a resource pool (or a slot does not belong to a resource pool) can be also referred to a slot unavailable for the resource pool. Therefore, a resource pool may consist of a plurality (set) of non-contiguous slots in the time domain. In a SL BWP, different resource pools may be assigned with different sets of slots. The UE may determine the set of slots assigned to a resource pool according to the (pre-)configurations. A transmitting UE may transmit one or more physical SL channels or one or more SL signals in one or more resource pools within a SL BWP, while a receiving UE may receive one or more physical SL channels or one or more SL signals in one or more resource pools within a SL BWP.

[0146] In the Figure 6, slot#0 refers to a first slot of a radio frame corresponding to SFN 0 of the serving cell or DFN 0. As illustrated in the Figure 6, a set of slots with indexes #4, #5, #7 and #10 belong to the resource pool. The slots in the set for a resource pool are re-indexed such that the logical slot indexes are successive from 0 to T'max-1 where the T'max is the number of the slot in the set. For example, in the Figure 6, the four slots in the set can be re-indexed as slots with logical slot indexes 0, 1, 2, and 3. The slots available for a resource pool may be provided or indicated by a parameter sl- TimeResource and may occur with a periodicity of 10240 ms.

[0147] The OFDM symbols within a slot assigned for sidelink transmission are provided by parameters included in the (pre-)configuration. To be specific, SL transmissions can start from a first symbol indicated by a parameter sl-StartSymbol and be within a number of consecutive symbols indicated by a parameter sl-LengthSymbols . As in the Figure 6, the duration 604 starts at the third OFDM symbol 603, which is indicated by the parameter sl-StartSymbol, and consists of 11 consecutive OFDM symbols which is indicated by the parameter sl-LengthSymbols . For a slot indicated for transmission of S-SS / PSBCH blocks, the first symbol and the number of consecutive symbols is predetermined.

[0148] In NR Releases 16 / 17, sidelink communication was developed to operate in licensed spectrum. In NR Release 18, to further support commercial use cases with increased sidelink data rate, sidelink communication over unlicensed spectrum is under discussion. Hereinafter, unlicensed spectrum refers to the above-mentioned unlicensed spectrum A, i.e., the shared spectrum.

[0149] As above-mentioned, operation over unlicensed spectrum should fulfill different regulatory limitations and restrictions, e.g., LBT requirements. For a sidelink transmission over the unlicensed spectrum, the UE may apply LBT procedure before performing a SL transmission. When LBT procedure is applied, the UE senses the channel to determine whether the channel is free or busy. Specifically, Physical layer may perform an LBT procedure before a SL transmission. In a case that the channel is sensed free, the UE (i.e., the Layer 1 of the UE) may perform the SL transmission. On the other hand, in a case that the channel is sensed busy, the UE (i.e., the Layer 1 of the UE 102) may not perform the SL transmission. Hereinafter, the SL transmission refers to a PSCCH / PSSCH transmission or a PSSCH transmission, unless stated otherwise in the present disclosure.

[0150] Given that LBT failure would prevent UE from performing a SL transmission, for a SL transmission within a slot, multiple SL starting locations within a slot can be configured in time domain such that opportunities of a SL transmission could be increased. In a present disclosure, for example, two sidelink starting locations within a slot may be configured in a SL BWP configuration.

[0151] However, when two sidelink starting locations within a slot are configured, how to determine SL slots available for resource pool(s) has not been specified. The present disclosure provides new methods and solutions on how to determine SL slotsthat are available for SL resource pool(s) for operation with shared spectrum channel access, which would provide a more efficient and flexible sidelink communication system.

[0152] Figure 7 is a diagram illustrating one implementation of a method 700 for determination of slots which may belong to a resource pool by a UE 102. In the present disclosure, a slot that may belong to a resource pool means the slot is able to be configured to a resource pool. However, a slot that may belong to a resource pool does not mean the slot must be configured to a resource pool. The term “a sidelink resource pool” here refers to a general category of resource pools and does not denote any specific resource pool. In the present disclosure, the term “a slot that may belong to a resource pool” and the term “a slot that is available for a resource pool” has same meaning and can be used interchangeably.

[0153] Hereinafter, for convenience of illustration, a SL slot may refer to a slot that may belong to a resource pool. In the time domain, a SL slot may be (pre-)configured or assigned to zero, one, or multiple resource pools. For example, a SL slot A may be (pre-)configured or assigned to one or more resource pools. In the time domain, a SL slot B may be (pre-)configured or assigned to a resource pool different from the one to which the SL slot A may be assigned. Conversely, a SL slot C in the time domain may not be (pre-)configured or assigned to any resource pool at all.

[0154] The UE 102 may receive 702, a first parameter, a second parameter, and a third parameter. These parameters are included in a SL BWP configuration. In other words, the UE may receive a SL BWP configuration wherein the SL BWP configuration may include the first parameter, the second parameter and the third parameter.

[0155] The first parameter indicates a location (i.e., a symbol index) of a first symbol used for sidelink transmission within a slot. For operation with shared spectrum channel access, in a case that the first parameter is present (included) in the SL BWP configuration, the UE may determine that the value of the first parameter indicates the symbol index of the first symbol used for sidelink within a slot. The first parameter may indicate the symbol index of the first symbol is one of 0, 1, 2, 3, 4, 5, 6. In a case that the first parameter is not present in the SL BWP configuration, the UE may determine that the symbol index of the first symbol used for sidelink within a slot is the symbol with index 0 within a slot.

[0156] The second parameter indicates a location (i.e., a symbol index) of a second symbol used for sidelink transmission within a slot. For operation with shared spectrum channel access, the second parameter is present in the SL BWP configuration and the UE may determine the value of the second parameter indicates the symbol index of the second symbol used for sidelink within a slot. The second parameter may indicate the symbol index of the second symbol is one of 3, 4, 5, 6, 7.

[0157] The third parameter indicates a number of consecutive symbols used for sidelink within a slot. The third parameter is present in the SL BWP configuration regardless of whether the UE may operate with shared spectrum channel access or without shared spectrum channel access.

[0158] In the implementation of the present disclosure, for operation with shared spectrum channel access, SL transmission may start from the first symbol and be within the number of the consecutive symbols within a SL slot or may start from the second symbol within a SL slot where the ending symbol of SL transmission starting from the first symbol is same as the ending symbol of SL transmission starting from the second symbol within a SL slot.

[0159] In the present disclosure, for operation without shared spectrum channel access, the SL BWP configuration may not include the first parameter and the second parameter and may include the fourth parameter. In other words, for operation without shared spectrum channel access, the UE may determine that a symbol index of a third symbol used for sidelink within a slot is indicated by the fourth parameter. For operation without shared spectrum channel access SL transmission may start from the third symbol and be within the number of the consecutive symbols within a SL slot. The fourth parameter may indicate the symbol index of the third symbol is one of 0, 1 , 2, 3, 4, 5, 6, 7.

[0160] On the other hand, for operation with shared spectrum channel access, in a case that the fourth parameter is present in the SL BWP configuration, the UE may not use the fourth parameter to determine the symbol index of a symbol used for sidelink within a slot, that is, the SL transmission may not start from the third symbol within a SL slot.

[0161] The first symbol used for sidelink within a slot may be also referred to as the first starting symbol within a slot. The second symbol used for sidelink within a slot may be also referred to as the second starting symbol within a slot. The third symbolused for sidelink within a slot may be also referred to as the third starting symbol within a slot.

[0162] The UE 102 may set 704, based on a received uplink and downlink TDD configuration, slot format per slot. The slot format includes downlink symbol, uplink symbols, and flexible symbols. In other words, an OFDM symbol in a slot can be classified as ‘downlink’, ‘flexible’, or ‘uplink’. Based on the uplink and downlink TDD configuration, the UE 102 is aware of symbol composition per slot.

[0163] In an example of 706 in the implementation, the UE 102 may determine, based on the first parameter and the third parameter, a symbol duration per slot. For each slot, the symbol duration starts from the first symbol indicated by the first parameter and is within the number of consecutive symbols indicated by the third parameter. The symbol duration is given or determined based on the first parameter and the third parameter. The symbol duration is given or determined not based on the second parameter. For each slot, the symbol duration starts from the first symbol indicated by the first parameter and is within the number of consecutive symbols indicated by the third parameter.

[0164] In another example of 706 in the implementation, the UE 102 may determine a symbol duration per slot wherein, for operation without shared spectrum channel access, the symbol duration in a slot is given based on the fourth parameter and the third parameter, and for operation with shared spectrum channel access, the symbol duration in a slot is given based on the first parameter and the third parameter. For operation without shared spectrum channel access, the symbol duration within a slot starts from the third symbol indicated by the fourth parameter and is within the number of consecutive symbols indicated by the third parameter. For operation with shared spectrum channel access, the symbol duration within a slot starts from the first symbol indicated by the first parameter and is within the number of consecutive symbols indicated by the third parameter.

[0165] Specifically, a slot is disqualified by the UE from being available for a resource pool if at least one symbol of the symbol duration in the slot is not configured as UL symbol. For purpose of illustration, in the present implementation, the symbol duration includes T-th, (T+l)-th, ..., (EEf-l)-th OFDM symbols in a slot. The UE 102 may determine that, for operation without shared spectrum channel access, the value of Y and the value of X are set (or indicated) by the fourth parameter and the thirdparameter, respectively; for operation with shared spectrum channel access, the value of 7 and the value of X are set (or indicated) by the first parameter and the third parameter, respectively. For operation with shared spectrum channel access, although the second parameter also provides a starting symbol in a slot, the UE 102 does not use the second parameter to set the value of Y.

[0166] The UE 102 may determine 708, whether a slot is available for a SL resource pool based on whether the symbol duration includes at least one symbol that is not uplink symbol. Specifically, in a case that at least one symbol of the symbol duration in a slot is not set as uplink symbol, the UE 102 may determine that the slot is not available for a SL resource pool, i.e., the slot may not belong to a resource pool. For a slot that is not available for a SL resource pool, the slot would not be assigned to any resource pool for SL transmission. The slot(s) that are not available for a SL resource pool based on the determination can be denoted as NnonSL.

[0167] In other words, the UE 102 may determine whether a slot is available for a SL resource pool based on the first parameter and the third parameter. The UE 102 may not use the second parameter to determine whether a slot is available for a SL resource pool.

[0168] Additionally or alternatively, the determination is performed as that, for operation without shared spectrum channel access, the UE 102 may determine whether a slot is available for a SL resource pool based on whether the symbol duration given by the fourth parameter and third parameter within the slot includes at least one symbol that is not configured as uplink symbol; for operation with shared spectrum channel access, the UE 102 may determine whether a slot is available for a SL resource pool based on whether the symbol duration given by the first parameter and third parameter within the slot includes at least one symbol that is not configured as uplink symbol.

[0169] In the present implementation, the UE 102 may also determine a slot is not available for a resource pool if the slot is configured for S-SS / PSBCH block transmission. The slot(s) configured for S-SS / PSBCH transmission can be denoted as N$-SSB -

[0170] The UE may further determine that reserved slots are not available for a resource pool. The determination of reserved slots is specified as below.

[0171] The UE may denote each slot during a time duration with 10240 msec. Then for a subcarrier spacing u, there are 10240 X 2Uslots per time duration. After excluding NS-SSBslot(s) and NnonSLslot(s) from the 10240 x 2Uslots, the remaining slots are denoted byarranged in increasing order of slot index. A slot lr(0 < r < 10240 x 2U— NS-SSB— NnonSB) belongs to thethe length of bitmap configured by higher layers.

[0172] For a resource pool, the UE 102 may assign a specific set of slots, from the slots that are available for the resource pool, to the resource pool based on utilizing the bitmap associated with the resource pool. Each resource pool has its corresponding bitmap, enabling the UE 102 to assign a distinct set of slots to each resource pool.

[0173] The UE 102 may perform 710, a SL transmission starting form the first symbol or the second symbol within a slot available for the resource pool. In other words, for operation with shared spectrum channel access and for an available slot, SL transmissions can start from a first symbol indicated by the first parameter and be within a number of consecutive symbols indicated by the third parameter, or from a second symbol indicated by the second parameter, where the ending symbol of SL transmissions starting from the first symbol is same as the ending symbol of SL transmissions starting from the second symbol.

[0174] In the present implementation, a method of determining whether slot(s) are available for a resource pool is provided, particularly for operation with shared spectrum channel access where two starting symbols within a slot are configured. In the method, SL transmission may commence from either the first symbol or the second symbol within a slot, depending on the outcome of LBT results. By prioritizing the first symbol, the method offers a more reliable way to identify suitable SL slots. The method can mitigate the risk that the available slot determined based on the second symbol can not be used for SL transmission. Therefore, an efficient SL communication system can be achieved according to the present implementation.

[0175] In sidelink communication, a SL UE in network coverage may transmit a S- SS / PSBCH block to other UEs that may be out of network coverage. The S-SS / PSBCH block may carry a bit sequence to indicate the receivers a number of SL slots that maybe used for SL transmission, Slots other the indicated SL slots may be used by the base station for downlink transmission. That is, the bit sequence can enable the receivers to be aware of the slots that the gNB may use for the downlink within the cell. Then receivers can then avoid causing interference to UEs that are receiving a downlink transmission in the cell by not performing SL transmissions in slots other than the indicated SL slots.

[0176] However, when two sidelink starting locations within a slot are configured, how to generate the bit sequence to be carried in the PSBCH has not been specified. The present disclosure provides new methods and solutions on how to generate a bit sequence to indicate SL slots for operation with shared spectrum channel access, which would provide a more efficient and flexible sidelink communication system.

[0177] Figure 8 is a diagram illustrating one implementation of a method 800 for generating a bit sequence to indicate SL slots in PSBCH by a UE 102. In the present implementation, for operation with shared spectrum channel access, there are two starting symbols for SL transmission configured within a slot.

[0178] The UE may receive 802, the first parameter and the second parameter. These parameters are included in a SL BWP configuration. In other words, the UE may receive a SL BWP configuration wherein the SL BWP configuration may include the first parameter and the second parameter. A SL transmission can be performed starting from the first symbol or from the second symbol within a SL slot.

[0179] The first parameter indicates a location (i.e., a symbol index) of a first symbol used for sidelink transmission within a slot. For operation with shared spectrum channel access, in a case that the first parameter is present (included) in the SL BWP configuration, the UE may determine that the value of the first parameter indicates the symbol index of the first symbol used for sidelink within a slot. The first parameter may indicate the symbol index of the first symbol is one of 0, 1, 2, 3, 4, 5, 6. In a case that the first parameter is not present in the SL BWP configuration, the UE may determine that the symbol index of the first symbol used for sidelink within a slot is the symbol with index 0 within a slot.

[0180] The second parameter indicates a location (i.e., a symbol index) of a second symbol used for sidelink transmission within a slot. For operation with shared spectrum channel access, the second parameter is present in the SL BWP configuration and the UE may determine the value of the second parameter indicates the symbol index of thesecond symbol used for sidelink within a slot. The second parameter may indicate the symbol index of the second symbol is one of 3, 4, 5, 6, 7.

[0181] In the implementation of the present disclosure, for operation without shared spectrum channel access, the SL B WP configuration may not include the first parameter and the second parameter and may include the fourth parameter. In other words, for operation without shared spectrum channel access, the UE may determine that a symbol index of a third symbol used for sidelink within a slot is indicated by the fourth parameter. For operation without shared spectrum channel access SL transmission may start from the third symbol and be within the number of the consecutive symbols within a SL slot. The fourth parameter may indicate the symbol index of the third symbol is one of 0, 1, 2, 3, 4, 5, 6, 7. On the other hand, for operation with shared spectrum channel access, in a case that the fourth parameter is present in the SL BWP configuration, the UE may not use the fourth parameter to determine the symbol index of a symbol used for sidelink within a slot, that is, the SL transmission may not start from the third symbol within a SL slot.

[0182] The UE may receive 804, an uplink and downlink TDD configuration. The uplink and downlink TDD configuration at least provides a number of slots with only uplink symbols and a number of uplink symbols. For illustration purpose, the number of slots with only uplink symbols can be denoted as usiots. The number of uplink symbols can be denoted as usym.

[0183] The UE 102 may determine or calculate 806, a number of SL slots at least by using the number of slots, the number of uplink symbols, and the symbol index of the first symbol. The number of SL slots can be denoted as u^iots. In other words, UE 102 may not use the symbol index of the second symbol to determine the number of SL slots. In other words, for the determination or calculation of the number of SL slotsUsiots, a symbol index Y is at least used where, for operation without shared spectrum channel access, the symbol index Y is the symbol index of the above-mentioned third symbol provided by the fourth parameter, and for operation with shared spectrum channel access, the symbol index Y is the symbol index of the above-mentioned first symbol provided by the first parameter.

[0184] To be specific, the number of SL slots is calculated asusiotsX+ 4. ure, is a reference subcarrier spacing that is providedby the uplink and downlink TDD configuration, u is the subcarrier spacing of the SLBWP that is provided by the SL BWP configuration. L is number of symbols in a slot. The determination of / xis based: if usymx 2u~Uref mod L > L — Y, the UE determine to set the value of 4 to 1, else, the UE determines to set the value of I±to 0. Here, the determination of Y is based: for operation without shared spectrum channel access, the UE may determine to set the value of Y to the symbol index of the above-mentioned third symbol provided by the fourth parameter, or for operation with shared spectrum channel access, the UE may determine to set the value of Y to the symbol index of the first symbol provided by the first parameter. Here, for operation with shared spectrum channel access, the UE may determine to not set the value of Y to the symbol index of the second symbol provided by the second parameter.

[0185] In other words, the UE may calculate the number of SL slots uf / Lotsby using the number of slots usiots, the number of uplink symbols usym, the SCS of the SL BWP u, the reference subcarriers spacing uref and the number of symbols in a slot L according to the formula The UE then maydetermine to whether increment u^iotsby 1 by using the value of Y, the number of uplink symbols usym, the SCS of the SL BWP u, the reference subcarriers spacing uree and the number of symbols in a slot L according to the formula usymX 2u~uref mod L > L — Y where, for operation without shared spectrum channel access, the UE may determine to set the value of Y to the symbol index of the above-mentioned third symbol provided by the fourth parameter, or for operation with shared spectrum channel access, the UE may determine to set the value of Y to the symbol index of the first symbol provided by the first parameter. Here, for operation with shared spectrum channel access, the UE may determine to not set the value of Y to the symbol index of the second symbol provided by the second parameter.

[0186] The UE 102 may then generate 808, a bit sequence to indicate the determined number of SL slots ufiots. In the implementation, the length of the bit sequence may be 7 bits.

[0187] The UE 102 may then transmit 810, to another UE, an PSBCH, the PSBCH including the generated bit sequence.

[0188] Figure 9 is a diagram illustrating one example 900 of generating a bit sequence to indicate SL slots in PSBCH by a UE 102. For convenience of illustration, in the example 900, the symbol index of the first symbol is indicated as 4 and the symbol index of the second symbol is indicated as 7. The SCS of the SL BWP is configured as u=0, i.e., 15kHz. The number of symbols in a slot L is equal to 14. The symbol index of the third symbol is indicated as 1.

[0189] The received uplink and downlink TDD configuration may include a RRC parameter referenceSubcarrierSpacing and a RRC parameter patternl. The RRC parameter referenceSubcarrierSpacing is used to indicate a SCS configuration (a reference SCS configuration) uref. The RRC parameter patternl may provide a slot configuration period of P msec by dl-UL-TransmissionPeriodicity, a number of slots dsiots with only downlink symbols by nrofDownlinkSlots, a number of downlink symbols asymby nrofDownlinkSymbols, a number of slots usiotswith only uplink symbols by nrofUplinkSlots, and a number of uplink symbols usyrrLby nrofUplinkSymbols. In the example, for convenience of illustration, the received uplink and downlink TDD configuration provides information such as the number of slots with only uplink symbols us[ots= 1 , the number of uplink symbols usym= 11 , the reference subcarrier spacing uref — 0 , i.e., 15kHz, the number of slots with only downlink symbol dsiots= 3(i.e., slot 901, slot 902, and slot 903), the number of uplink symbols dsym= 2, and P — 5msec. hr the example 900, the first dsym= 2 symbols of the slot 904 are downlink symbols. The last usym= 11 symbols of the slot 904 are uplink symbols. And the remaining 1 symbol in the slot 904 is flexible symbol.

[0190] The UE may calculate the number of SL slots ufiotsfor a period of P = 5msec by using the number of slots uslots, the number of uplink symbols usym, the SCS of the SL BWP u, the reference subcarriers spacing uref and the number of symbols in a slot L according to the formula ufyts= uslotsX 2u~Uref + In the example 900, the number of SL slotsis equal to 1. The UEthen may determine to whether increment u^otsby 1 by using the value of Y. For operation without shared spectrum channel access, the UE may determine to set the value of Y to the symbol index of the above-mentioned third symbol provided by the fourth parameter. In this case, given usymX 2u~Uref mod L = 11 is less than (L — Y =13), the Usiotsis not incremented by 1. That is, the number of u$iotsis 1. Then the UE may generate the bit sequence “0000001” to indicate the two SL slots.

[0191] For operation with shared spectrum channel access, the UE may determine to set the value of Y to the symbol index of the above-mentioned first symbol provided by the first parameter. In this case, given usymx 2u~Uref mod L = 11 is larger than (L — Y = 9), the Usiotsis incremented by 1. That is, the number of Ugiotsis 2. Then the UE may generate the bit sequence “0000010” to indicate the two SL slots.

[0192] In the present implementation, a method of generating a bit sequence to indicate a number of SL slots per period P is provided, for operation without shared spectrum channel access and operation with shared spectrum channel access where two starting symbols within a slot are configured. By utilizing the first symbol, a common understanding of how to interpret the bit sequence between a transmitter and a received could be aligned, which provides an efficient SL communication system.

[0193] Figure 10 illustrates various components that may be utilized in a UE 1002. The UE 1002 (UE 102) described in connection with Figure 10 may be implemented in accordance with the UE 102 described in connection with Figure 1. The UE 1002 includes a processor 1081 that controls operation of the UE 1002. The processor 1081 may also be referred to as a central processing unit (CPU). Memory 1087, which may include read-only memory (ROM), random access memory (RAM), a combination of the two or any type of device that may store information, provides instructions 1083a and data 1085a to the processor 1081. A portion of the memory 1087 may also include non-volatile random access memory (NVRAM). Instructions 1083b and data 1085b may also reside in the processor 1081 . Instructions 1083b and / or data 1085b loaded into the processor 1081 may also include instructions 1083a and / or data 1085a from memory 1087 that were loaded for execution or processing by the processor 1081. The instructions 1083b may be executed by the processor 1081 to implement one or more of the methods described above.

[0194] The UE 1002 may also include a housing that contains one or more transmitters 1058 and one or more receivers 1020 to allow transmission and reception of data. The transmitter(s) 1058 and receiver(s) 1020 may be combined into one or more transceivers 1018. One or more antennas 1022a-n are attached to the housing and electrically coupled to the transceiver 1018.

[0195] The various components of the UE 1002 are coupled together by a bus system 1089, which may include a power bus, a control signal bus and a status signal bus, in addition to a data bus. However, for the sake of clarity, the various buses are illustrated in Figure 10 as the bus system 1089. The UE 1002 may also include a digital signal processor (DSP) 1091 for use in processing signals. The UE 1002 may also include a communications interface 1093 that provides user access to the functions of the UE 1002. The UE 1002 illustrated in Figure 10 is a functional block diagram rather than a listing of specific components.

[0196] Figure 11 illustrates various components that may be utilized in a base station 1160. The base station 1160 described in connection with Figure 11 may be implemented in accordance with the base station 160 described in connection with Figure 1. The base station 1160 includes a processor 1181 that controls operation of the base station 1160. The processor 1181 may also be referred to as a central processing unit (CPU). Memory 1187, which may include read-only memory (ROM), random access memory (RAM), a combination of the two or any type of device that may store information, provides instructions 1183a and data 1185a to the processor 1181. A portion of the memory 1187 may also include non-volatile random access memory (NVRAM). Instructions 1183b and data 1185b may also reside in the processor 1181. Instructions 1183b and / or data 1185b loaded into the processor 1181 may also include instructions 1183a and / or data 1185a from memory 1187 that were loaded for execution or processing by the processor 1181. The instructions 1183b may be executed by the processor 1181 to implement one or more of the methods 300 described above.

[0197] The base station 1160 may also include a housing that contains one or more transmitters 1117 and one or more receivers 1178 to allow transmission and reception of data. The transmitter(s) 1117 and receiver(s) 1178 may be combined into one or more transceivers 1176. One or more antennas 1180a-n are attached to the housing and electrically coupled to the transceiver 1176.

[0198] The various components of the base station 1160 are coupled together by a bus system 1189, which may include a power bus, a control signal bus and a status signal bus, in addition to a data bus. However, for the sake of clarity, the various buses are illustrated in Figure 11 as the bus system 1189. The base station 1160 may also include a digital signal processor (DSP) 1191 for use in processing signals. The base station 1160 may also include a communications interface 1193 that provides useraccess to the functions of the base station 1160. The base station 1160 illustrated in Figure 11 is a functional block diagram rather than a listing of specific components.

[0199] The term “computer-readable medium” refers to any available medium that can be accessed by a computer or a processor. The term “computer-readable medium,” as used herein, may denote a computer- and / or processor-readable medium that is non- transitory and tangible. By way of example, and not limitation, a computer-readable or processor-readable medium may comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer or processor. Disk and disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray® disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers.

[0200] It should be noted that one or more of the methods described herein may be implemented in and / or performed using hardware. For example, one or more of the methods described herein may be implemented in and / or realized using circuitry, a chipset, an application-specific integrated circuit (ASIC), a large-scale integrated circuit (LSI) or integrated circuit, etc.

[0201] Each of the methods disclosed herein comprises one or more steps or actions for achieving the described method. The method steps and / or actions may be interchanged with one another and / or combined into a single step without departing from the scope of the claims. In other words, unless a specific order of steps or actions is required for proper operation of the method that is being described, the order and / or use of specific steps and / or actions may be modified without departing from the scope of the claims.

[0202] It is to be understood that the claims are not limited to the precise configuration and components illustrated above. Various modifications, changes and variations may be made in the arrangement, operation and details of the systems, methods and apparatus described herein without departing from the scope of the claims.

Claims

[CLAIMS]1. A user equipment (UE), comprising: a reception circuitry configured to receive an uplink and downlink TDD configuration, the uplink and downlink TDD configuration providing a number of slots with only uplink symbols, a number of uplink symbols; a control circuitry configured to determine a number of sidelink (SL) slots at least by using the number of slots, the number of uplink symbols, and a symbol index, and to generate a bit sequence to indicate the determined number of SL slots; and a transmission circuitry configured to transmit, to another UE, an PSBCH, the PSBCH including the generated bit sequence, wherein, for operation with shared spectrum channel access, a SL BWP configuration includes a first parameter and a second parameter, the first parameter indicates a first starting symbol used for SL within a slot, the second parameter indicates a second starting symbol used for SL within a slot, and the symbol index is set to a symbol index of the first starting symbol.

2. The UE according to the claim 1 : wherein in case that the first parameter is not included in the SL BWP configuration, a symbol index of the first starting symbol is determined as a symbol index 0 in a slot.

3. The UE according to the claim 1 : wherein the control circuitry is configured to determine that, for operation without shared spectrum channel access, the symbol index is set to a symbol index of a starting symbol, the starting symbol being indicated by a fourth parameter included in the SL BWP configuration.

4. The UE according to the claim 1 : wherein a length of the generated bit sequence is 7 bits.A communication method performed by a user equipment (UE), comprising: receiving an uplink and downlink TDD configuration, the uplink and downlink TDD configuration providing a number of slots with only uplink symbols, a number of uplink symbols; determining a number of sidelink (SL) slots at least by using the number of slots, the number of uplink symbols, and a symbol index; generating a bit sequence to indicate the determined number of SL slots; and transmitting, to another UE, an PSBCH, the PSBCH including the generated bit sequence, wherein, for operation with shared spectrum channel access, a SL BWP configuration includes a first parameter and a second parameter, the first parameter indicates a first starting symbol used for SL within a slot, the second parameter indicates a second starting symbol used for SL within a slot, and the symbol index is set to a symbol index of the first starting symbol.

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