WO2019195505A1

WO2019195505A1 - Control information signaling and procedure for new radio (nr) vehicle-to-everything (v2x) communications

Info

Publication number: WO2019195505A1
Application number: PCT/US2019/025714
Authority: WO
Inventors: Chunxuan Ye; Fengjun Xi; Kyle Jung-Lin Pan
Original assignee: Idac Holdings, Inc.
Priority date: 2018-04-04
Filing date: 2019-04-04
Publication date: 2019-10-10
Also published as: TW202005317A

Abstract

Methods and apparatus are disclosed for new radio (NR) vehicle-to-everything (V2X) communications. A transmitting wireless transmit/receive unit (WTRU) may generate and attach cyclic redundancy check (CRC) bits to sidelink data. The WTRU may low-density parity check (LDPC) encode and rate match the sidelink data and the CRC bits attached to the sidelink data. The WTRU may scramble the rate matched sidelink data with a data scrambling sequence, and the data scrambling sequence may be based on at least a source identifier (ID). Also, the WTRU may modulate the scrambled sidelink data to generate a sidelink data message, and then transmit the sidelink data message to a receiving WTRU. Also, the data scrambling sequence may be based on a data scrambling sequence initialization value, which value may include at least one of a full sidelink control information (SCI) CRC, a partial SCI CRC, a destination ID or a data scrambling constant.

Description

CONTROL INFORMATION SIGNALING AND PROCEDURE FOR NEW RADIO (NR) VEHICLE-

TO-EVERYTHING (V2X) COMMUNICATIONS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 62/652,845, filed April 4, 2018 and U.S. Provisional Application No. 62/753,378, filed October 31 , 2018, the contents of which are incorporated herein by reference.

BACKGROUND

[0002] Vehicle-to-everything (V2X) communications architecture has been developed for wireless communication systems, including those which use an evolved packet core (EPC). V2X communications may include one or more of vehicle-to-vehicle (V2V) communications, vehicle-to- pedestrian (V2P) communications, vehicle-to-infrastructure (V2I) communications and Vehicle-to- Network (V2N) communications.

[0003] In New Radio (NR) several deployment scenarios are defined, for example, indoor hotspot, dense urban, rural, urban macro, high speed, etc. On top of these deployment scenarios, three use cases are defined: Enhanced Mobile Broadband (eMBB), Massive Machine Type Communications (mMTC) and Ultra Reliable and Low Latency Communications (URLLC). Different use cases may focus on different requirements such as higher data rate, higher spectrum efficiency, low power and higher energy efficiency, lower latency and higher reliability. Each deployment scenario and use case will require different control information signaling.

SUMMARY

[0004] Methods and apparatus are disclosed for data and control information signaling and procedures for new radio (NR) vehicle-to-everything (V2X) communications. In an example, a transmitting wireless transmit/receive unit (WTRU) may generate and attach cyclic redundancy check (CRC) bits to sidelink data. The WTRU may then low-density parity check (LDPC) encode and rate matching the sidelink data and the CRC bits attached to the sidelink data. Further, the WTRU may scramble the rate matched sidelink data with a data scrambling sequence, and the data scrambling sequence may be based on at least a source identifier (ID). Also, the WTRU may modulate the scrambled sidelink data to generate a sidelink data message. The WTRU may then transmit the sidelink data message to a receiving WTRU. In a further example, the data scrambling sequence may be based on a data scrambling sequence initialization value. Further, the data scrambling sequence initialization value may include at least one of a full sidelink control information (SCI) CRC, a partial SCI CRC, a destination ID or a data scrambling constant. In a further example, the data scrambling constant may have a value of between 1008 and 1023.

[0005] Moreover, the sidelink data message may be transmitted over a sidelink data channel. In a further example, the sidelink data channel may be a physical sidelink shared channel (PSSCH). In an additional example, the receiving WTRU may be part of a group of receiving WTRUs. In a further example, the destination ID may be a destination group ID.

[0006] In another example, the transmitting WTRU may reorder SCI payload bits. The

WTRU may then generate and attach CRC bits to the reordered SCI payload bits. Further, the WTRU may polar encode and rate match the reordered SCI payload bits and the CRC bits attached to the SCI payload. Subsequently, the WTRU may scramble the rate matched SCI payload bits with an SCI scrambling sequence. Also, the WTRU may then modulate the scrambled SCI payload bits to generate an SCI message. In addition, the WTRU may transmit the generated SCI message to the receiving WTRU.

[0007] In a further example, the SCI scrambling sequence may be based on an SCI scrambling sequence initialization value. Further, the SCI scrambling sequence initialization value may include at least one of a full SCI CRC, a partial SCI CRC, a destination ID, a source ID, a radio network temporary identifier (RNTI) or an SCI scrambling constant. In an example, the SCI scrambling constant may have a value of between 1008 and 1023.

[0008] In an additional example, the SCI payload may include at least one of a frequency resource location of the current transmission field, a modulation and coding scheme field, a new data indicator field, a hybrid automatic repeat request (FIARQ) process number field, a redundancy version field, a transmit power control (TPC) command field, a Code Block Group Transmission Information (CBGTI) field, a sidelink assignment index field, or a time duration for PSSCH transmission field. In a further example, the SCI message may be transmitted over a sidelink control channel.

[0009] In another example, the sidelink data and the SCI message may be transmitted as part of at least one of a unicast transmission or a groupcast transmission. In a further example, the sidelink control channel may be a physical sidelink control channel (PSCCFI). Further, the transmitting WTRU may receive a feedback SCI message from the receiving WTRU over the PSCCFI. Moreover, the feedback SCI message may include at least one of FIARQ feedback or channel state information (CSI) feedback. In another example, the received feedback SCI message may be transmitted over the PSSCH or may be transmitted piggybacked on the PSSCH.

[0010] In an additional example, a receiving WTRU may receive a sidelink data message from a transmitting WTRU. The WTRU may then demap one or more data channel resources of a sidelink data channel to obtain modulation symbols, based on a decoded SCI field of time duration for PSSCH transmission. Further, the WTRU may demodulate sidelink data from the received sidelink data message based on the modulation symbols. In an example, the modulation symbols may be based on one or more decoded SCI modulation and coding scheme (MCS) fields. Also, the WTRU may descramble the demodulated sidelink data with a data scrambling sequence. In another example, the data scrambling sequence may be based on at least a source ID. Moreover, the WTRU may rate-dematch the descrambled sidelink data and CRC bits attached to the descrambled sidelink data. Subsequently, the WTRU may LDPC encode the rate dematched sidelink data and CRC bits attached to the descrambled sidelink data. In addition, the WTRU may perform a CRC check on and remove the CRC bits attached to the descrambled sidelink data.

[001 1] Moreover, the sidelink data message may be received over the sidelink data channel. Further, the receiving WTRU may transmit a feedback SCI message over the PSCCFI to the transmitting WTRU. Moreover, the feedback SCI message may include at least one of FIARQ feedback or CSI feedback. In another example, the transmitted feedback SCI message may be transmitted over the PSSCH or transmitted piggybacked on the PSSCH.

[0012] In another example, the receiving WTRU may receive an SCI message from the transmitting WTRU. Further, the receiving WTRU may demap one or more control channel resources of a sidelink control channel to obtain modulation symbols. In addition, the receiving WTRU may demodulate SCI payload bits from the received SCI message based on the modulation symbols. Also, the receiving WTRU may descramble the demodulated SCI payload bits with an SCI scrambling sequence. Moreover, the receiving WTRU may rate dematch and polar decode the descrambled SCI payload bits and CRC bits attached to the descrambled SCI payload bits. Further, the receiving WTRU may perform a CRC demask and check on and remove the CRC bits attached to the descrambled SCI payload bits. Additionally, the receiving WTRU may reorder the checked SCI payload bits on a condition that the CRC check is passed.

[0013] Further, the SCI message may be received over a sidelink control channel. Also, the sidelink data and the SCI message may be received as part of at least one of a unicast transmission or a groupcast transmission. Moreover, the sidelink control channel may be a PSCCFI. In addition, a feedback SCI may be transmitted by the receiving WTRU to the transmitting WTRU over the PSCCFI. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] A more detailed understanding may be had from the following description, given by way of example in conjunction with the accompanying drawings, wherein like reference numerals in the figures indicate like elements, and wherein:

[0015] FIG. 1A is a system diagram illustrating an example communications system in which one or more disclosed embodiments may be implemented;

[0016] FIG. 1 B is a system diagram illustrating an example wireless transmit/receive unit

(WTRU) that may be used within the communications system illustrated in FIG. 1A according to an embodiment;

[0017] FIG. 1 C is a system diagram illustrating an example radio access network (RAN) and an example core network (CN) that may be used within the communications system illustrated in FIG. 1A according to an embodiment;

[0018] FIG. 1 D is a system diagram illustrating a further example RAN and a further example CN that may be used within the communications system illustrated in FIG. 1A according to an embodiment;

[0019] FIG. 2 is an example diagram of a polar coding procedure for V2X Downlink Control

Information (DCIs) or Sidelink Control Information (SCI);

[0020] FIG. 3 is an example diagram of DCI payload mapping;

[0021] FIG. 4 is an example diagram of SCI payload mapping;

[0022] FIG. 5 is an example diagram of initialization values of the scrambling sequence for broadcast sidelink;

[0023] FIG. 6 is an example diagram of initialization values of the scrambling sequence for unicast or groupcast sidelink that depend on a destination identifier (ID);

[0024] FIG. 7 is an example diagram of initialization values of the scrambling sequence for unicast or groupcast sidelink that depend on both the destination ID and a physical sidelink control channel (PSCCFI) cyclic redundancy check (CRC);

[0025] FIG. 8 is an example diagram of initialization values of the scrambling sequence for unicast or groupscast sidelink that on both destination ID and source ID;

[0026] FIG. 9 is an example diagram of initialization values of the scrambling sequence for unicast or groupcast sidelink that depend on destination ID, source ID, and PSCCFI CRC;

[0027] FIG. 10 is a flow diagram of a procedure for setting the initialization values for a physical sidelink shared channel (PSSCFH) scrambling sequence;

[0028] FIG. 1 1 is another flow diagram of a procedure for setting the initialization values for a PSSCFH scrambling sequence; [0029] FIG. 12 is a flow diagram of an example process for a sidelink WTRU transmitter to process a control channel and a data channel; and

[0030] FIG. 13 is a flow diagram of an example process for a sidelink WTRU receiver to process a control channel and a data channel.

DETAILED DESCRIPTION

[0031] FIG. 1A is a diagram illustrating an example communications system 100 in which one or more disclosed embodiments may be implemented. The communications system 100 may be a multiple access system that provides content, such as voice, data, video, messaging, broadcast, etc., to multiple wireless users. The communications system 100 may enable multiple wireless users to access such content through the sharing of system resources, including wireless bandwidth. For example, the communications systems 100 may employ one or more channel access methods, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single-carrier FDMA (SC-FDMA), zero-tail unique-word discrete Fourier transform Spread orthogonal frequency division multiplexing (OFDM) (ZT-UW-DFT-S-OFDM), unique word OFDM (UW-OFDM), resource block-filtered OFDM, filter bank multicarrier (FBMC), and the like.

[0032] As shown in FIG. 1A, the communications system 100 may include wireless transmit/receive units (WTRUs) 102a, 102b, 102c, 102d, a radio access network (RAN) 104, a core network (ON) 106, a public switched telephone network (PSTN) 108, the Internet 1 10, and other networks 1 12, though it will be appreciated that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and/or network elements. Each of the WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and/or communicate in a wireless environment. By way of example, the WTRUs 102a, 102b, 102c, 102d, any of which may be referred to as a station (STA), may be configured to transmit and/or receive wireless signals and may include a user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a subscription-based unit, a pager, a cellular telephone, a personal digital assistant (PDA), a smartphone, a laptop, a netbook, a personal computer, a wireless sensor, a hotspot or Mi-Fi device, an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, a medical device and applications (for example, remote surgery), an industrial device and applications (for example, a robot and/or other wireless devices operating in an industrial and/or an automated processing chain contexts), a consumer electronics device, a device operating on commercial and/or industrial wireless networks, and the like. Any of the WTRUs 102a, 102b, 102c and 102d may be interchangeably referred to as a UE. [0033] The communications systems 100 may also include a base station 1 14a and/or a base station 114b. Each of the base stations 1 14a, 1 14b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks, such as the CN 106, the Internet 1 10, and/or the other networks 112. By way of example, the base stations 1 14a, 1 14b may be a base transceiver station (BTS), a NodeB, an eNode B (eNB), a Home Node B, a Home eNode B, a next generation NodeB, such as a gNode B (gNB), a new radio (NR) NodeB, a site controller, an access point (AP), a wireless router, and the like. While the base stations 1 14a, 1 14b are each depicted as a single element, it will be appreciated that the base stations 1 14a, 114b may include any number of interconnected base stations and/or network elements.

[0034] The base station 1 14a may be part of the RAN 104, which may also include other base stations and/or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), relay nodes, and the like. The base station 1 14a and/or the base station 1 14b may be configured to transmit and/or receive wireless signals on one or more carrier frequencies, which may be referred to as a cell (not shown). These frequencies may be in licensed spectrum, unlicensed spectrum, or a combination of licensed and unlicensed spectrum. A cell may provide coverage for a wireless service to a specific geographical area that may be relatively fixed or that may change over time. The cell may further be divided into cell sectors. For example, the cell associated with the base station 1 14a may be divided into three sectors. Thus, in one embodiment, the base station 1 14a may include three transceivers, i.e., one for each sector of the cell. In an embodiment, the base station 1 14a may employ multiple-input multiple output (MIMO) technology and may utilize multiple transceivers for each sector of the cell. For example, beamforming may be used to transmit and/or receive signals in desired spatial directions.

[0035] The base stations 114a, 1 14b may communicate with one or more of the WTRUs

102a, 102b, 102c, 102d over an air interface 1 16, which may be any suitable wireless communication link (for example, radio frequency (RF), microwave, centimeter wave, micrometer wave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 1 16 may be established using any suitable radio access technology (RAT).

[0036] More specifically, as noted above, the communications system 100 may be a multiple access system and may employ one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and the like. For example, the base station 1 14a in the RAN 104 and the WTRUs 102a, 102b, 102c may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may establish the air interface 116 using wideband CDMA (WCDMA). WCDMA may include communication protocols such as High-Speed Packet Access (HSPA) and/or Evolved HSPA (HSPA+). HSPA may include High-Speed Downlink (DL) Packet Access (HSDPA) and/or High-Speed Uplink (UL) Packet Access (HSUPA).

[0037] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface 1 16 using Long Term Evolution (LTE) and/or LTE-Advanced (LTE-A) and/or LTE-Advanced Pro (LTE-A Pro).

[0038] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as NR Radio Access, which may establish the air interface 1 16 using NR.

[0039] In an embodiment, the base station 1 14a and the WTRUs 102a, 102b, 102c may implement multiple radio access technologies. For example, the base station 1 14a and the WTRUs 102a, 102b, 102c may implement LTE radio access and NR radio access together, for instance using dual connectivity (DC) principles. Thus, the air interface utilized by WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and/or transmissions sent to/from multiple types of base stations (for example, an eNB and a gNB).

[0040] In other embodiments, the base station 1 14a and the WTRUs 102a, 102b, 102c may implement radio technologies such as IEEE 802.1 1 (i.e., Wireless Fidelity (WiFi), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), and the like.

[0041] The base station 1 14b in FIG. 1A may be a wireless router, Home Node B, Home eNode B, or access point, for example, and may utilize any suitable RAT for facilitating wireless connectivity in a localized area, such as a place of business, a home, a vehicle, a campus, an industrial facility, an air corridor (for example, for use by drones), a roadway, and the like. In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.1 1 to establish a wireless local area network (WLAN). In an embodiment, the base station 1 14b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In yet another embodiment, the base station 114b and the WTRUs 102c, 102d may utilize a cellular-based RAT (for example, WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR etc.) to establish a picocell or femtocell. As shown in FIG. 1A, the base station 1 14b may have a direct connection to the Internet 1 10. Thus, the base station 1 14b may not be required to access the Internet 1 10 via the CN 106. [0042] The RAN 104 may be in communication with the CN 106, which may be any type of network configured to provide voice, data, applications, and/or voice over internet protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may have varying quality of service (QoS) requirements, such as differing throughput requirements, latency requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, and the like. The CN 106 may provide call control, billing services, mobile location- based services, pre-paid calling, Internet connectivity, video distribution, etc., and/or perform high- level security functions, such as user authentication. Although not shown in FIG. 1A, it will be appreciated that the RAN 104 and/or the CN 106 may be in direct or indirect communication with other RANs that employ the same RAT as the RAN 104 or a different RAT. For example, in addition to being connected to the RAN 104, which may be utilizing a NR radio technology, the CN 106 may also be in communication with another RAN (not shown) employing a GSM, UMTS, CDMA 2000, WiMAX, E-UTRA, or WiFi radio technology.

[0043] The CN 106 may also serve as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 1 10, and/or the other networks 1 12. The PSTN 108 may include circuit-switched telephone networks that provide plain old telephone service (POTS). The Internet 1 10 may include a global system of interconnected computer networks and devices that use common communication protocols, such as the transmission control protocol (TCP), user datagram protocol (UDP) and/or the internet protocol (IP) in the TCP/IP internet protocol suite. The networks 1 12 may include wired and/or wireless communications networks owned and/or operated by other service providers. For example, the networks 1 12 may include another CN connected to one or more RANs, which may employ the same RAT as the RAN 104 or a different RAT.

[0044] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communications system

100 may include multi-mode capabilities (for example, the WTRUs 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks over different wireless links). For example, the WTRU 102c shown in FIG. 1A may be configured to communicate with the base station 1 14a, which may employ a cellular-based radio technology, and with the base station 1 14b, which may employ an IEEE 802 radio technology.

[0045] FIG. 1 B is a system diagram illustrating an example WTRU 102. As shown in FIG.

1 B, the WTRU 102 may include a processor 1 18, a transceiver 120, a transmit/receive element 122, a speaker/microphone 124, a keypad 126, a display/touchpad 128, non-removable memory 130, removable memory 132, a power source 134, a global positioning system (GPS) chipset 136, and/or other peripherals 138, among others. It will be appreciated that the WTRU 102 may include any subcombination of the foregoing elements while remaining consistent with an embodiment. [0046] The processor 1 18 may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), any other type of integrated circuit (IC), a state machine, and the like. The processor 1 18 may perform signal coding, data processing, power control, input/output processing, and/or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 1 18 may be coupled to the transceiver 120, which may be coupled to the transmit/receive element 122. While FIG. 1 B depicts the processor 1 18 and the transceiver 120 as separate components, it will be appreciated that the processor 1 18 and the transceiver 120 may be integrated together in an electronic package or chip.

[0047] The transmit/receive element 122 may be configured to transmit signals to, or receive signals from, a base station (for example, the base station 1 14a) over the air interface 1 16. For example, in one embodiment, the transmit/receive element 122 may be an antenna configured to transmit and/or receive RF signals. In an embodiment, the transmit/receive element 122 may be an emitter/detector configured to transmit and/or receive IR, UV, or visible light signals, for example. In yet another embodiment, the transmit/receive element 122 may be configured to transmit and/or receive both RF and light signals. It will be appreciated that the transmit/receive element 122 may be configured to transmit and/or receive any combination of wireless signals.

[0048] Although the transmit/receive element 122 is depicted in FIG. 1 B as a single element, the WTRU 102 may include any number of transmit/receive elements 122. More specifically, the WTRU 102 may employ MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit/receive elements 122 (for example, multiple antennas) for transmitting and receiving wireless signals over the air interface 1 16.

[0049] The transceiver 120 may be configured to modulate the signals that are to be transmitted by the transmit/receive element 122 and to demodulate the signals that are received by the transmit/receive element 122. As noted above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers for enabling the WTRU 102 to communicate via multiple RATs, such as NR and IEEE 802.1 1 , for example.

[0050] The processor 1 18 of the WTRU 102 may be coupled to, and may receive user input data from, the speaker/microphone 124, the keypad 126, and/or the display/touchpad 128 (for example, a liquid crystal display (LCD) display unit or organic light-emitting diode (OLED) display unit). The processor 1 18 may also output user data to the speaker/microphone 124, the keypad 126, and/or the display/touchpad 128. In addition, the processor 1 18 may access information from, and store data in, any type of suitable memory, such as the non-removable memory 130 and/or the removable memory 132. The non-removable memory 130 may include random-access memory (RAM), read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. In other embodiments, the processor 1 18 may access information from, and store data in, memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0051] The processor 1 18 may receive power from the power source 134, and may be configured to distribute and/or control the power to the other components in the WTRU 102. The power source 134 may be any suitable device for powering the WTRU 102. For example, the power source 134 may include one or more dry cell batteries (for example, nickel-cadmium (NiCd), nickel- zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, and the like.

[0052] The processor 1 18 may also be coupled to the GPS chipset 136, which may be configured to provide location information (for example, longitude and latitude) regarding the current location of the WTRU 102. In addition to, or in lieu of, the information from the GPS chipset 136, the WTRU 102 may receive location information over the air interface 1 16 from a base station (for example, base stations 1 14a, 114b) and/or determine its location based on the timing of the signals being received from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information by way of any suitable location-determination method while remaining consistent with an embodiment.

[0053] The processor 1 18 may further be coupled to other peripherals 138, which may include one or more software and/or hardware modules that provide additional features, functionality and/or wired or wireless connectivity. For example, the peripherals 138 may include an accelerometer, an e-compass, a satellite transceiver, a digital camera (for photographs and/or video), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands free headset, a Bluetooth® module, a frequency modulated (FM) radio unit, a digital music player, a media player, a video game player module, an Internet browser, a Virtual Reality and/or Augmented Reality (VR/AR) device, an activity tracker, and the like. The peripherals 138 may include one or more sensors. The sensors may be one or more of a gyroscope, an accelerometer, a hall effect sensor, a magnetometer, an orientation sensor, a proximity sensor, a temperature sensor, a time sensor; a geolocation sensor, an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, a humidity sensor and the like.

[0054] The WTRU 102 may include a full duplex radio for which transmission and reception of some or all of the signals (for example, associated with particular subframes for both the UL (for example, for transmission) and DL (for example, for reception) may be concurrent and/or simultaneous. The full duplex radio may include an interference management unit to reduce and or substantially eliminate self-interference via either hardware (for example, a choke) or signal processing via a processor (for example, a separate processor (not shown) or via processor 118). In an embodiment, the WTRU 102 may include a half-duplex radio for which transmission and reception of some or all of the signals (for example, associated with particular subframes for either the UL (for example, for transmission) or the DL (for example, for reception)).

[0055] FIG. 1 C is a system diagram illustrating the RAN 104 and the CN 106 according to an embodiment. As noted above, the RAN 104 may employ an E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0056] The RAN 104 may include eNode-Bs 160a, 160b, 160c, though it will be appreciated that the RAN 104 may include any number of eNode-Bs while remaining consistent with an embodiment. The eNode-Bs 160a, 160b, 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 1 16. In one embodiment, the eNode-Bs 160a, 160b, 160c may implement MIMO technology. Thus, the eNode-B 160a, for example, may use multiple antennas to transmit wireless signals to, and/or receive wireless signals from, the WTRU 102a.

[0057] Each of the eNode-Bs 160a, 160b, 160c may be associated with a particular cell

(not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the UL and/or DL, and the like. As shown in FIG. 1 C, the eNode-Bs 160a, 160b, 160c may communicate with one another over an X2 interface.

[0058] The CN 106 shown in FIG. 1 C may include a mobility management entity (MME)

162, a serving gateway (SGW) 164, and a packet data network (PDN) gateway (PGW) 166. While the foregoing elements are depicted as part of the CN 106, it will be appreciated that any of these elements may be owned and/or operated by an entity other than the CN operator.

[0059] The MME 162 may be connected to each of the eNode-Bs 162a, 162b, 162c in the

RAN 104 via an S1 interface and may serve as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, bearer activation/deactivation, selecting a particular serving gateway during an initial attach of the WTRUs 102a, 102b, 102c, and the like. The MME 162 may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as GSM and/or WCDMA.

[0060] The SGW 164 may be connected to each of the eNode Bs 160a, 160b, 160c in the

RAN 104 via the S1 interface. The SGW 164 may generally route and forward user data packets to/from the WTRUs 102a, 102b, 102c. The SGW 164 may perform other functions, such as anchoring user planes during inter-eNode B handovers, triggering paging when DL data is available for the WTRUs 102a, 102b, 102c, managing and storing contexts of the WTRUs 102a, 102b, 102c, and the like.

[0061] The SGW 164 may be connected to the PGW 166, which may provide the WTRUs

102a, 102b, 102c with access to packet-switched networks, such as the Internet 1 10, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0062] The CN 106 may facilitate communications with other networks. For example, the

CN 106 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices. For example, the CN 106 may include, or may communicate with, an IP gateway (for example, an IP multimedia subsystem (IMS) server) that serves as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to the other networks 1 12, which may include other wired and/or wireless networks that are owned and/or operated by other service providers.

[0063] Although the WTRU is described in FIGS. 1A-1 D as a wireless terminal, it is contemplated that in certain representative embodiments that such a terminal may use (for example, temporarily or permanently) wired communication interfaces with the communication network.

[0064] In representative embodiments, the other network 1 12 may be a WLAN.

[0065] A WLAN in Infrastructure Basic Service Set (BSS) mode may have an Access Point

(AP) for the BSS and one or more stations (STAs) associated with the AP. The AP may have access or an interface to a Distribution System (DS) or another type of wired/wireless network that carries traffic in to and/or out of the BSS. Traffic to STAs that originates from outside the BSS may arrive through the AP and may be delivered to the STAs. Traffic originating from STAs to destinations outside the BSS may be sent to the AP to be delivered to respective destinations. Traffic between STAs within the BSS may be sent through the AP, for example, where the source STA may send traffic to the AP and the AP may deliver the traffic to the destination STA. The traffic between STAs within a BSS may be considered and/or referred to as peer-to-peer traffic. The peer- to-peer traffic may be sent between (for example, directly between) the source and destination STAs with a direct link setup (DLS). In certain representative embodiments, the DLS may use an 802.1 1 e DLS or an 802.1 1 z tunneled DLS (TDLS). A WLAN using an Independent BSS (IBSS) mode may not have an AP, and the STAs (for example, all of the STAs) within or using the IBSS may communicate directly with each other. The IBSS mode of communication may sometimes be referred to herein as an“ad-hoc” mode of communication. [0066] When using the 802.1 1 ac infrastructure mode of operation or a similar mode of operations, the AP may transmit a beacon on a fixed channel, such as a primary channel. The primary channel may be a fixed width (for example, 20 MHz wide bandwidth) or a dynamically set width. The primary channel may be the operating channel of the BSS and may be used by the STAs to establish a connection with the AP. In certain representative embodiments, Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) may be implemented, for example in 802.11 systems. For CSMA/CA, the STAs (for example, every STA), including the AP, may sense the primary channel. If the primary channel is sensed/detected and/or determined to be busy by a particular STA, the particular STA may back off. One STA (for example, only one station) may transmit at any given time in a given BSS.

[0067] High Throughput (HT) STAs may use a 40 MHz wide channel for communication, for example, via a combination of the primary 20 MHz channel with an adjacent or nonadjacent 20 MHz channel to form a 40 MHz wide channel.

[0068] Very High Throughput (VHT) STAs may support 20MHz, 40 MHz, 80 MHz, and/or

160 MHz wide channels. The 40 MHz, and/or 80 MHz, channels may be formed by combining contiguous 20 MHz channels. A 160 MHz channel may be formed by combining 8 contiguous 20 MHz channels, or by combining two non-contiguous 80 MHz channels, which may be referred to as an 80+80 configuration. For the 80+80 configuration, the data, after channel encoding, may be passed through a segment parser that may divide the data into two streams. Inverse Fast Fourier Transform (IFFT) processing, and time domain processing, may be done on each stream separately. The streams may be mapped on to the two 80 MHz channels, and the data may be transmitted by a transmitting STA. At the receiver of the receiving STA, the above described operation for the 80+80 configuration may be reversed, and the combined data may be sent to the Medium Access Control (MAC).

[0069] Sub 1 GHz modes of operation are supported by 802.1 1 af and 802.1 1 ah. The channel operating bandwidths, and carriers, are reduced in 802.1 1 af and 802.1 1 ah relative to those used in 802.1 1 h, and 802.1 1 ac. 802.11 af supports 5 MHz, 10 MHz, and 20 MHz bandwidths in the TV White Space (TVWS) spectrum, and 802.11 ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using non-TVWS spectrum. According to a representative embodiment, 802.11 ah may support Meter Type Control/Machine-Type Communications (MTC), such as MTC devices in a macro coverage area. MTC devices may have certain capabilities, for example, limited capabilities including support for (for example, only support for) certain and/or limited bandwidths. The MTC devices may include a battery with a battery life above a threshold (for example, to maintain a very long battery life). [0070] WLAN systems, which may support multiple channels, and channel bandwidths, such as 802.11 h, 802.1 1 ac, 802.11 at, and 802.1 1 ah, include a channel which may be designated as the primary channel. The primary channel may have a bandwidth equal to the largest common operating bandwidth supported by all ST As in the BSS. The bandwidth of the primary channel may be set and/or limited by a STA, from among all STAs in operating in a BSS, which supports the smallest bandwidth operating mode. In the example of 802.1 1 ah, the primary channel may be 1 MHz wide for STAs (for example, MTC type devices) that support (for example, only support) a 1 MHz mode, even if the AP, and other STAs in the BSS support 2 MHz, 4 MHz, 8 MHz, 16 MHz, and/or other channel bandwidth operating modes. Carrier sensing and/or Network Allocation Vector (NAV) settings may depend on the status of the primary channel. If the primary channel is busy, for example, due to a STA (which supports only a 1 MHz operating mode) transmitting to the AP, all available frequency bands may be considered busy even though a majority of the available frequency bands remains idle.

[0071] In the United States, the available frequency bands, which may be used by

802.1 1 ah, are from 902 MHz to 928 MHz. In Korea, the available frequency bands are from 917.5 MHz to 923.5 MHz. In Japan, the available frequency bands are from 916.5 MHz to 927.5 MHz. The total bandwidth available for 802.1 1 ah is 6 MHz to 26 MHz depending on the country code.

[0072] FIG. 1 D is a system diagram illustrating the RAN 104 and the CN 106 according to an embodiment. As noted above, the RAN 104 may employ an NR radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0073] The RAN 104 may include gNBs 180a, 180b, 180c, though it will be appreciated that the RAN 104 may include any number of gNBs while remaining consistent with an embodiment. The gNBs 180a, 180b, 180c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 1 16. In one embodiment, the gNBs 180a, 180b, 180c may implement MIMO technology. For example, gNBs 180a, 108b may utilize beamforming to transmit signals to and/or receive signals from the gNBs 180a, 180b, 180c. Thus, the gNB 180a, for example, may use multiple antennas to transmit wireless signals to, and/or receive wireless signals from, the WTRU 102a. In an embodiment, the gNBs 180a, 180b, 180c may implement carrier aggregation technology. For example, the gNB 180a may transmit multiple component carriers to the WTRU 102a (not shown). A subset of these component carriers may be on unlicensed spectrum while the remaining component carriers may be on licensed spectrum. In an embodiment, the gNBs 180a, 180b, 180c may implement Coordinated Multi-Point (CoMP) technology. For example, WTRU 102a may receive coordinated transmissions from gNB 180a and gNB 180b (and/or gNB 180c). [0074] The WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using transmissions associated with a scalable numerology. For example, the OFDM symbol spacing and/or OFDM subcarrier spacing may vary for different transmissions, different cells, and/or different portions of the wireless transmission spectrum. The WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using subframe or transmission time intervals (TTIs) of various or scalable lengths (for example, containing a varying number of OFDM symbols and/or lasting varying lengths of absolute time).

[0075] The gNBs 180a, 180b, 180c may be configured to communicate with the WTRUs

102a, 102b, 102c in a standalone configuration and/or a non-standalone configuration. In the standalone configuration, WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c without also accessing other RANs (for example, such as eNode-Bs 160a, 160b, 160c). In the standalone configuration, WTRUs 102a, 102b, 102c may utilize one or more of gNBs 180a, 180b, 180c as a mobility anchor point. In the standalone configuration, WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using signals in an unlicensed band. In a non- standalone configuration WTRUs 102a, 102b, 102c may communicate with/connect to gNBs 180a, 180b, 180c while also communicating with/connecting to another RAN such as eNode-Bs 160a, 160b, 160c. For example, WTRUs 102a, 102b, 102c may implement DC principles to communicate with one or more gNBs 180a, 180b, 180c and one or more eNode-Bs 160a, 160b, 160c substantially simultaneously. In the non-standalone configuration, eNode-Bs 160a, 160b, 160c may serve as a mobility anchor for WTRUs 102a, 102b, 102c and gNBs 180a, 180b, 180c may provide additional coverage and/or throughput for servicing WTRUs 102a, 102b, 102c.

[0076] Each of the gNBs 180a, 180b, 180c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the UL and/or DL, support of network slicing, DC, interworking between NR and E-UTRA, routing of user plane data towards User Plane Function (UPF) 184a, 184b, routing of control plane information towards Access and Mobility Management Function (AMF) 182a, 182b and the like. As shown in FIG. 1D, the gNBs 180a, 180b, 180c may communicate with one another over an Xn interface.

[0077] The CN 106 shown in FIG. 1D may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one Session Management Function (SMF) 183a, 183b, and possibly a Data Network (DN) 185a, 185b. While the foregoing elements are depicted as part of the CN 106, it will be appreciated that any of these elements may be owned and/or operated by an entity other than the CN operator. [0078] The AMF 182a, 182b may be connected to one or more of the gNBs 180a, 180b,

180c in the RAN 104 via an N2 interface and may serve as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, support for network slicing (for example, handling of different protocol data unit (PDU) sessions with different requirements), selecting a particular SMF 183a, 183b, management of the registration area, termination of non-access stratum (NAS) signaling, mobility management, and the like. Network slicing may be used by the AMF 182a, 182b in order to customize CN support for WTRUs 102a, 102b, 102c based on the types of services being utilized WTRUs 102a, 102b, 102c. For example, different network slices may be established for different use cases such as services relying on ultrareliable low latency (URLLC) access, services relying on enhanced massive mobile broadband (eMBB) access, services for MTC access, and the like. The AMF 182a, 182b may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as LTE, LTE-A, LTE-A Pro, and/or non-3^rd Generation Partnership Project (non-3GPP) access technologies such as WiFi.

[0079] The SMF 183a, 183b may be connected to an AMF 182a, 182b in the CN 106 via an N1 1 interface. The SMF 183a, 183b may also be connected to a UPF 184a, 184b in the CN 106 via an N4 interface. The SMF 183a, 183b may select and control the UPF 184a, 184b and configure the routing of traffic through the UPF 184a, 184b. The SMF 183a, 183b may perform other functions, such as managing and allocating UE IP address, managing PDU sessions, controlling policy enforcement and QoS, providing DL data notifications, and the like. A PDU session type may be IP-based, non-IP based, Ethernet-based, and the like.

[0080] The UPF 184a, 184b may be connected to one or more of the gNBs 180a, 180b,

180c in the RAN 104 via an N3 interface, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. The UPF 184, 184b may perform other functions, such as routing and forwarding packets, enforcing user plane policies, supporting multihomed PDU sessions, handling user plane QoS, buffering DL packets, providing mobility anchoring, and the like.

[0081] The CN 106 may facilitate communications with other networks. For example, the

CN 106 may include, or may communicate with, an IP gateway (for example, an IP multimedia subsystem (IMS) server) that serves as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to the other networks 1 12, which may include other wired and/or wireless networks that are owned and/or operated by other service providers. In one embodiment, the WTRUs 102a, 102b, 102c may be connected to a local DN 185a, 185b through the UPF 184a, 184b via the N3 interface to the UPF 184a, 184b and an N6 interface between the UPF 184a, 184b and the DN 185a, 185b.

[0082] In view of FIGs. 1A-1 D, and the corresponding description of FIGs. 1A-1 D, one or more, or all, of the functions described herein with regard to one or more of: WTRU 102a-d, Base Station 1 14a-b, eNode-B 160a-c, MME 162, SGW 164, PGW 166, gNB 180a-c, AMF 182a-b, UPF 184a-b, SMF 183a-b, DN 185a-b, and/or any other device(s) described herein, may be performed by one or more emulation devices (not shown). The emulation devices may be one or more devices configured to emulate one or more, or all, of the functions described herein. For example, the emulation devices may be used to test other devices and/or to simulate network and/or WTRU functions.

[0083] The emulation devices may be designed to implement one or more tests of other devices in a lab environment and/or in an operator network environment. For example, the one or more emulation devices may perform the one or more, or all, functions while being fully or partially implemented and/or deployed as part of a wired and/or wireless communication network in order to test other devices within the communication network. The one or more emulation devices may perform the one or more, or all, functions while being temporarily implemented/deployed as part of a wired and/or wireless communication network. The emulation device may be directly coupled to another device for purposes of testing and/or performing testing using over-the-air wireless communications.

[0084] The one or more emulation devices may perform the one or more, including all, functions while not being implemented/deployed as part of a wired and/or wireless communication network. For example, the emulation devices may be utilized in a testing scenario in a testing laboratory and/or a non-deployed (for example, testing) wired and/or wireless communication network in order to implement testing of one or more components. The one or more emulation devices may be test equipment. Direct RF coupling and/or wireless communications via RF circuitry (for example, which may include one or more antennas) may be used by the emulation devices to transmit and/or receive data.

[0085] 3GPP vehicle-to-everything (V2X) Use Cases are discussed herein. In the 3GPP

V2X standardization process, there are several developed use cases. These include vehicle platooning, sensor and state map sharing, remote driving, and automated cooperative driving.

[0086] Vehicle platooning may be considered to be operating a group of vehicles in a closely linked manner so that the vehicles move like a train with virtual strings attached between vehicles. To maintain vehicle distance, the vehicles may share status information among themselves. By using platooning, the distances between vehicles can be reduced, and the number of needed drivers can be reduced. This could lower overall fuel consumption. In the 5G V2X evaluation methodology study, vehicle platooning is one of the prioritized use cases.

[0087] A vehicle blockage scenario is examined herein. Vehicle blockage may result in the dramatic reduction of signal strength, especially for a high carrier frequency, say above 6 gigahertz (GHz). A proposal is to treat vehicle blockage as a separate state, beyond a line-of-sight state and a non-line-of-sight state.

[0088] In 3GPP V2X, a vehicle may be in transmission mode 3, and may be described as a mode 3 user, or may be in transmission mode 4, and may be described as a mode 4 user. A mode 3 user directly uses the resources allocated by a base station for sidelink (SL) communication among vehicles or between a vehicle and a pedestrian. Mode 4 user may obtain a list of candidate resources allocated by a base station, and may select a resource among the candidate resources for its SL communication. In NR V2X, a vehicle may be in transmission mode 1 , similar to transmission mode 3 in LTE V2X. Also, in NR V2X, a vehicle may be in transmission mode 2, similar to transmission 4 in LTE V2X. In the following descriptions, transmission mode 1 may be used interchangeable with mode 3, and remain consistent with the examples provided herein. Also, transmission mode 2 may be used interchangeable with mode 4, and remain consistent with the examples provided herein.

[0089] It should be noted that the user, UE, or WTRU may refer to a vehicle, a vehicle user or a user in a vehicle. These terms may be used interchangeably and remain consistent with the examples provided herein.

[0090] LTE V2X control information is discussed herein. In LTE, downlink control information (DCI) format 5A may be used for the scheduling of a physical sidelink control channel (PSCCH). Also, several sidelink control information (SCI) format 1 fields may be used for the scheduling of a physical sidelink shared channel (PSSCH).

[0091] In an example in sidelink communication, a transmitting WTRU may transmit control information over the PSCCH to a receiving WTRU. Further, the transmitting WTRU may transmit data over the PSSCH to the receiving WTRU. In addition, the receiving WTRU may also transmit feedback over at least one of the PSCCH or the PSSCH to the transmitting WTRU. The transmitting WTRU may also be referred to as a transmitter WTRU, a WTRU transmitter, a source WTRU or an originating WTRU, and these terms may be used interchangeably and remain consistent with the examples provided herein. Further, the receiving WTRU may also be referred to as a receiver WTRU, a WTRU receiver or a destination WTRU, and these terms may be used interchangeably and remain consistent with the examples provided herein. [0092] The payload of DCI format 5A may include: a carrier indicator, which may be 3 bits; a lowest index of the subchannel allocation to the initial transmission, which may be flog₂ (A¾,_channel )] bits; one or more SCI format 1 fields; and an SL index field, which may be 2 bits. The one or more SCI format 1 fields may include a field for frequency resource location of initial transmission and retransmission, and a field for a time gap between initial transmission and retransmission. Further, the SL index field may be present only for cases with time division duplex (TDD) operation with one or more of uplink-downlink configurations 0-6. When the DCI format 5A cyclic redundancy check (CRC) is scrambled with a SL-SPS-V-RNTI, the following fields may be present: an SL SPS configuration index, which may be 3 bits; and an activation/release indication, which may be 1 bit.

[0093] If the number of information bits in format 5A mapped onto a given search space is less than the payload size of format 0 mapped onto the same search space, zeros shall be appended to format 5A until the payload size equals that of format 0 including any padding bits appended to format 0. If the format 5A CRC is scrambled by SL-V-RNTI, if the number of information bits in format 5A mapped onto a given search space is less than the payload size of format 5A with CRC scrambled by SL-SPS-V-RNTI mapped onto the same search space, and if format 0 is not defined on the same search space, zeros shall be appended to format 5A until the payload size equals that of format 5A with CRC scrambled by SL-SPS-V-RNTI.

[0094] In LTE, SCI format 1 is used for the scheduling of PSSCH. The payload of SCI format 1 may include: a priority field, which may be 3 bits; a resource reservation field, which may be 4 bits; a frequency resource location of initial transmission and retransmission field, which may be expressed as

+i)/ 2)1 bits; a field for a time gap between initial transmission and retransmission, which may be 4 bits; a modulation and coding scheme, which may be 5 bits; a retransmission index, which may be 1 bit; and reserved information bits, which may be added until the size of SCI format 1 is equal to 32 bits. The reserved bits are set to zero.

[0095] In LTE V2X, the control information or data information is encoded and rate matched. Before modulating these coded and rate matched bits, they are scrambled with a scrambling sequence. The general scrambling sequence is a length 31 gold sequence. The scrambling sequence generator shall be initialized by an initialization value, which is denoted by C_init. For PSCCH, C_init is equal to 510. A reason for this initialization value is because the PSCCH is supposed to be received by all the nearby WTRUs, as it is for broadcast sidelink, and it contains necessary information for all the WTRUs, for example, for resource reservation purpose, even those WTRUS which are not interested in receiving the corresponding PSSCH data. For PSSCH, C_init is set to n _D 2¹⁴ + n_ssf 2⁹ + 510, where n _D equals the decimal representation of CRC (16 bits) on the PSCCH transmitted in the same subframe as the PSSCH, and n_ssf denotes the subframe index in a radio frame (5 bits).

[0096] In NR, the scrambling of a physical downlink control channel (PDCCH) is based on a gold sequence with an initialization value C_init set to (n_RNTI 2¹⁶ + n_ID) mod 2³¹, where n_ID equals the cell identifier (ID) (10 bits) or PDCCH demodulation reference signal (DMRS) scrambling ID (16 bits) if configured. The scrambling of a physical uplink control channel (PUCCH) (format 2/3/4) is based on a gold sequence with an initialization value C_init set to n_RNXI 2¹⁵ + n_ID, where n_ID equals cell ID (10 bits) or physical uplink shared channel PUSCH data scrambling ID (10 bits) if configured. In NR, the scrambling of physical downlink shared channel (PDSCH) is based on a gold sequence with an initialization value C_init set to n_RNTI 2¹⁵ + q 2¹⁴ + n_ID, where n_ID equals cell ID (10 bits) or PDSCH data scrambling ID (10 bits) if configured and q is the codedword index. The scrambling of PUSCH is based on a gold sequence with an initialization value C_init set to ⁿRNTi ' 2¹⁵ + n_ID, where n_ID equals cell ID (10 bits) or PUSCH data scrambling ID (10 bits) if configured. Also in NR, the DMRS for PDCCH is scrambled by a gold sequence with an initialization value C_init set

)mod 2³¹, where 1 is the OFDM symbol number within the slot, n)?_f is the slot number within a frame, and N_ID is the PDCCH DMRS scrambling ID or cell ID. The DMRS for PDSCH is scrambled by a gold sequence with an initialization value C_init set to C_init = (2¹⁷

+ ⁿsciD)^m°d 2³¹, where the quantity n_SCID e {0,1} is given by the DMRS sequence initialization field.

[0097] Accordingly, several problems should be addressed with respect to NR V2X control information contents, and NR V2X control information coding procedures. Several DCI formats are defined in NR for the transmissions on the Uu link. However, the DCI format to specifically schedule the V2X transmissions has not yet been defined in NR. Furthermore, the SCI format has not yet been defined in NR for the transmissions on the sidelink. Hence, it is desirable to define the DCI format and the SCI format for the NR V2X operations. This is mainly for the support of new V2X use cases, using the new features introduced in NR. Furthermore, the DCI format and the SCI format for NR device-to-device (D2D) operations may also be designed. In addition, new DCI and SCI formats may be used for other use cases.

[0098] The control information in LTE is coded by tail-biting convolutional codes (TBCC) or

Reed-Muller (RM) codes. In NR, polar codes and RM codes are used for control information. Specifically, if the uplink control information (UCI) payload size is above 1 1 bits, then it is encoded by a polar code. Otherwise, it is encoded by an RM code. The DCI is always encoded by a polar code. The channel coding procedures for some DCI and UCI have been specified in NR. However, the polar coding procedures for SCI and V2X-related DCI have not yet been specified in NR. Hence, it is desirable to design the polar coding procedure for SCI and V2X-related DCI.

[0099] Further, a scrambling solution for NR V2X sidelink is needed. The LTX V2X sidelink only supports broadcast, where both the PSCCH and PSSCH are supposed to be capable of being received by any nearby WTRU, such as a WTRU in a vehicle. Hence, the scrambling of the PSCCH is based on a common gold sequence with a constant initialization value. The scrambling of the PSSCH is based on the subframe index, as well as the CRC of its associated PSCCH. This scrambling approach could avoid the mismatch between the PSCCH and PSSCH.

[0100] In NR V2X, the sidelink could be either broadcast, groupcast or unicast. The

PSSCH data for groupcast or unicast may not be leaked to an irrelevant WTRU. The scrambling of PSSCH should be based on a WTRU specific sequence. This could also reduce interference. In addition, the subcarrier spacing in NR is flexible, and the number of slots in a radio frame depends on the NR numerology used. The number of supported physical cell IDs in NR is increased to 1008, while this number is 504 in LTE. Hence, it is desirable to redesign the scrambling of the NR PSSCH to include scrambling for NR V2X sidelink communication.

[0101] New and modified DCI formats for V2X transmissions are discussed herein. In an example, zero padding in V2X-related DCI is provided. In LTE, the DCI format 0 is used to schedule the PUSCH in one UL cell, and the DCI format 5A is used to schedule the PSCCH and PSSCH. The payload size of DCI format 5A is matched up to the payload size of format 0, since the SL transmissions use the resources of UL transmissions.

[0102] In NR, it is expected that the SL transmissions also use the resources of UL transmissions. If a new DCI format is designed for NR V2X transmissions, then the payload of this DCI format could be matched to the DCI formats for PUSCH scheduling. Here, the zero padding bits may be used. Instead of padding zeros to the end of the information bits as in LTE, part or all of the zero-padding bits could be assigned in different locations relative to information bits. This could be based on polar code features to achieve better block error rate (BLER) performance.

[0103] Two new DCI formats for V2X are provided in examples. In NR, there are two DCI formats for PUSCH scheduling: DCI format 0_0 and DCI format 0_1. The DCI format 0_0 is for scheduling PUSCH in a legacy way, while the DCI format 0_1 is for scheduling PUSCH in a new way or in a way supporting new features of NR. These two DCI formats could be extended to the V2X-related DCI formats. Suppose two new DCI formats are designed for V2X. As discussed further herein, these two DCI formats may be referred to as DCI format 3_0 and DCI format 3_1. The payload size of DCI format 3_0 may match the payload size of DCI format 0_0 and the payload size of DCI format 3_1 may match the payload size of DCI format 0_1.

[0104] There is an alternative way to separate the usage of DCI format 3_0 and DCI format 3_1. In LTE V2X, the sidelink transmission is mainly broadcast. To support new V2X use cases, the sidelink transmission could be unicast or multicast. In an example, multicast transmission may be considered to be equivalent to a groupcast transmission. In an example, some unicast sidelink transmissions are used in advanced driving use cases. To support new unicast sidelink use cases, the contents of the corresponding DCI could be designed properly. The DCI for scheduling unicast/multicast sidelink could be associated with DCI format 3_1 , while the DCI for scheduling broadcast sidelink could be associated with DCI format 3_0.

[0105] Contents for an NR DCI format are proposed herein. Consider LTE DCI format 5A with the following payloads: a carrier indicator; a lowest index of the subchannel allocation to the initial transmission; SCI format 1 fields with frequency resource location of initial transmission and retransmission; SCI format 1 fields with a time gap between initial transmission and retransmission; an SL index; an SL SPS configuration index; and an activation/release indication. In an example, the last two items are only used in the semi-persistent scheduling (SPS) configuration case.

[0106] The NR DCI format could contain one or more of the following fields. This may apply to either DCI format 3_0 or DCI format 3_1. For example, the carrier indicator field may contain cross-carrier scheduling information. In an example, this field could be 0 or 3 bits.

[0107] Further, the bandwidth part indicator field may contain the information regarding which bandwidth part (BWP) could be used for the sidelink transmissions. In an example, this field could be 0, 1 or 2 bits, depending on the system configurations of the BWP.

[0108] Moreover, the lowest index of the sub-channel allocation to the initial transmission may be a field in the NR DCI format. In an example, the number of subchannels in SL, for example in the BWP, may be N _subchannel- This SL may occupy the whole band or occupy the BWP. This field may have log₂ [W_s¾,_cftanneil bits.

[0109] In addition, a time domain resource assignment may be a field in the NR DCI format. The transmissions on NR sidelink are assumed to be slot based, where the slot duration may vary. Hence, the time domain resource assignment may be needed to schedule the time resource for the PSCCH transmission. The time domain resource assignment may provide a row index of a higher layer configured table. The table may be referred to as a pssch-symbol Allocation, and may define the slot offset, the start and length indicator and the PSSCH mapping type to be applied in the PSSCH transmission. [01 10] Also, an SCI contents field may be a field in the NR DCI format, and may include frequency resource location of initial transmission and retransmission. This SCI field may have l°g₂ \N subchannel (Subchannel + 1 ] bits, indicating the starting and the length of contiguously allocated subchannels.

[01 1 1] Further, another SCI contents field may be a field in the NR DCI format, and may include a time gap between initial transmission and retransmission. In LTE, this SCI field is 4 bits to provides up to a 15 sub-frames, or 15 millisecond (ms), gap. In NR, this time gap could be expressed in the unit of slots. This time gap may depend on the numerology configured. For example, for larger subcarrier spacing, more bits on the time gap could be used. This is because each slot has a shorter duration, and the absolute time difference between the initial transmission and retransmission could be expressed in terms of a greater number of slots. For smaller subcarrier spacing, fewer bits on the time gap could be used. This is because each slot has a longer duration, and the absolute time difference between the initial transmission and retransmission could be expressed in terms of a fewer number of slots. For example, for a sub-carrier spacing of 15 kilohertz (KHz), 4 bits could be used to indicate up to a 15 ms gap with a granularity of 1 ms. For a subcarrier spacing of 30 KHz, 5 bits could be used to indicate up to a 15 ms gap with a granularity of 0.5 ms. For a sub-carrier spacing of 60 KHz, 6 bits could be used to indicate up to a 15 ms gap with a granularity of 0.25 ms. For a subcarrier spacing of 120 KHz, 7 bits could be used to indicate up to a 15 ms gap with a granularity of 0.125 ms. For a subcarrier spacing of 240 KHz, 8 bits could be used to indicate up to a 15 ms gap with a granularity of 0.0625 ms. In summary, the number of bits could be 4-Hog_2 (SP/(15 KHz)) bits, where SP is the subcarrier spacing.

[01 12] In further examples, the time gap may be expressed in other ways, such as in time symbols. In addition, this field may be ignored if the sidelink communication applies the new transmission schemes as discussed elsewhere herein.

[01 13] In addition, a further SCI contents field may be a field in the NR DCI format, and may include an SL index. The SL index may indicate the slot offset of the sidelink transmissions. This also may define an SL channel with a specific frequency domain channel offset value. It is expected that the number of sidelink channels in NR V2X could be larger than in LTE V2X. Hence, it is propose to have more than 2 bits for the SL index. For example, there could be 3 bits for the SL index which maps to the indicated value m as in the following table: Table 1 : Exemplary mapping of NR DCI format offset field to indicated value m

[01 14] This indicated value of m may specify the starting slot for the PSSCH/PSCCH transmissions. In case there are x bits of the SL index field for transmission mode 3 UE, then there may be a PSSCH/PSCCH transmission no earlier than T_DL -

x T_s + ( 2^X + m) x Time_siot,

where TDL is the start of the DL slot carrying the DCI, N_TA and T_s are used to determine the timing advance, and Time_siot is the time duration for a slot. The length of the SL index field may depend on the numerology of the system, which may related, for example, to the subcarrier spacing used. For a smaller subcarrier spacing, the length of the SL index field may be larger. For a larger subcarrier spacing, the length of SL index field may be smaller.

[01 15] An SL SPS (configured grant type 2) configuration index field may be a field in the

NR DCI format, and may provide the SPS configuration index used for sidelink. This field could have 3 bits, in an example.

[01 16] Also, an activation/release indication field may be a field in the NR DCI format, and may indicate whether the DCI is to activate or release the SPS configuration. This field has 1 bit, in an example.

[01 17] In addition, a padding bits field may be a field in the NR DCI format, and may contain a certain number of zero-padding bits, so that the overall payload size of DCI format 3_0 is equal to that of DCI format 0_0, and the overall payload size of DCI format 3_1 is equal to that of DCI format 0_1. A further number of padding bits may be used for other DCI formats, in other examples.

[01 18] New example SCI formats for V2X transmissions are described herein. An LTE SCI format 1 may include the following payloads: priority; resource reservation; frequency resource location of initial transmission and retransmission; time gap between initial transmission and retransmission; modulation and coding scheme (MCS); retransmission index; and reserved information bits.

[01 19] Two SCI formats for V2X are proposed herein in examples. There could be two NR

SCI formats for PSSCH scheduling. For example, these formats may be SCI format 1_0 and SCI format 1_1. The SCI format 1_0 may be used for scheduling PSSCH in a legacy way, while the SCI format 1_1 may be used for scheduling PSSCH in a new way or in a way supporting new features of NR.

[0120] An alternative way to separate SCI format 1_0 and SCI format 1_1 is that the scheduling unicast/multicast sidelink may be associated with SCI format 1_1 , while the scheduling broadcast sidelink may be associated with SCI format 1_0. In addition examples, further information could be provided by way of the SCI formats.

[0121] Example contents for NR SCI formats are also proposed herein. In LTE V2X, the sidelink transmission is mainly for broadcast. To support new V2X use cases, the sidelink transmission may be unicast or multicast. For example, some unicast sidelink transmissions are used in advanced driving use cases. Some multicast sidelink transmissions are used in the vehicle platooning use cases. To support new unicast or multicast sidelink use cases, the contents of the corresponding SCI could be designed properly. For example, a new SCI format to support the unicast or multicast V2X sidelink may be proposed.

[0122] The NR SCI format may contain one or more of the following fields. For example, a priority field may specify the data priority level, which may be associated with resource reservation. In examples, this field may have 3 bits, or it may have 4 bits to support one or more of more priority levels, a latency requirement or a reliability level.

[0123] In another example, a resource reservation field may specify the resource reservations for the future sidelink communications. This field may have 4 bits, or more bits to support more resource reservation cases.

[0124] In a further example, a frequency resource location of the current transmission field may specify the frequency resource location used for PSSCH transmission. In an example, the number bits of the payload may be

+ l)/2], indicating the start or the duration of the PSSCH. In another example, the number bits of payload may be ^g₂ \N_s ^si_bchannei \, indicating the duration of the PSSCH.

[0125] In an additional example, a modulation and coding scheme field may contain the

MCS index used for PSSCH channel. Several MCS tables may be defined for eMBB and URLLC. The selection among different MCS tables may be configured by a radio resource control (RRC) configuration. The MCS index may be 5 bits, as for an eMBB case, or it may be 4 bits for some simplified MCS tables.

[0126] Also, a new data indicator field may be used for the SCI to support unicast transmissions. For example, this field may be used to indicate when new data is scheduled in the current PSSCH transmission. In an example, this field may be 1 bit.

[0127] Moreover, a hybrid automatic repeat request (HARQ) process number may be used. Specifically, for unicast-based sidelink, multiple HARQ processes could be supported. This field may identify which HARQ process the current PSSCH transmission belongs to. In an example, the HARQ processes supported for NR V2X could be smaller than that in NR eMBB use cases, due to the latency requirement. Hence, the payload size for the HARQ process number could be less than 4 bits, for example, 1 bit, 2 bits or 3 bits.

[0128] In yet another example, a redundancy version field may be used. In an example, multiple redundancy versions (RV)s may be supported for the retransmissions of the data. Although low-density parity check (LDPC) codes are used for a data channel with up to 4 RVs, one could use only a partial amount of the RVs for sidelink transmissions. For example, only RV0 and RV2 may be used to obtain the best BLER performance. In another example, only RV0 and RV3 may be used to obtain the self-decodable feature of each RV in case some transmissions are corrupted.

[0129] It is also possible to support the reverse order on the modulation mapper for an RV, such as RV0. For example, one RV may provide natural order modulation mapping, while another RV may provide reverse order modulation mapping. In a specific example, let b_Q, b₁, b₂, b₃ be 4 continuous rate matched bits to be transmitted. If the RV is 0, then ( b₀ , b_x, b₂, b₃) is mapped a 16- quadrature amplitude modulation (QAM) symbol. If the RV is 1 , then ( b₃ , b₂, b_lt b₀) is mapped to a 16-QAM symbol. Hence, the payload size for an RV could be 1 bit, in an example.

[0130] In still another example, a transmit power control (TPC) command for a scheduled

PSSCH field may contain the TPC command used for setting the power of the PSSCH. The field may be 2 bits, for example.

[0131] In addition, a. Code Block Group Transmission Information (CBGTI) field may contain the CBGTI information for the current transmission. It may be a bitmap with length of configured code block groups (CBGs). The bit 0 may indicate the CBG is not contained in the current transmission, and the bit 1 may indicate the CBG is contained in the current transmission. It is possible that the set of the size of configured CBGs for sidelink communication could be a subset of the set of the size of configured CBGs for downlink/uplink communication. This is because the transport block size in sidelink communication could be less than that in downlink/uplink communication, and consequently, the total number of scheduled CBGs could be less in the sidelink case. For example, the configured CBGs could be {0, 2} or {0, 2, 4} or {0, 2, 4, 6}. Hence, the payload of CBGTI could be 0, 2, 4 or 6 bits, in examples.

[0132] Also, a sidelink assignment index field may indicate the number of sidelink subframes with PSCCH that are to be acknowledged. In other words, the value may indicate the number of SL HARQ-ACK reports that are to be transmitted on PSSCH or PSCCH. This field may be 1 or 2 bits, depending on whether a semi-static HARQ-ACK codebook or dynamic HARQ-ACK codebook is used.

[0133] Moreover, a time duration for PSSCH transmission field may be used. In LTE, the

PSSCH and PSCCH occur in the same sub-frame. To support the high data rate in NR V2X use cases, the time domain resource in NR PSSCH could be more than 1 subframe (or slot), and may be different from an LTE PSSCH. Hence, an example may specify the duration of the NR PSSCH. Suppose that a single sidelink transmission could occupy up to N^ax slots- slots. Then ^{this fielcl} could contain log₂ v a_{X Siot}] bits, indicating the time duration of this transmission. Further, the time duration of this transmission may be provided in terms of slots. The maximum number of slots may be N^ax slots- Further, the maximum number of slots for aggregation can be configured, preconfigured or fixed.

[0134] Further a padding bits or reserved bits field may be used. This field may be included to match the payload of the new SCI format to some fixed size.

[0135] New radio network temporary identifiers (RNTIs) for multicast and unicast sidelink are provided in examples herein. To support the unicast or multicast V2X sidelink, one or more new RNTIs could be defined. For example, besides an SL-V-RNTI and an SL-SPS-V-RNTI, one may define an SL-VG-RNTI and an SL-SPS-VG-RNTI, where the source vehicle and target group of vehicles could use these RNTIs in their communications. The SL-VG-RNTI and SL-SPS-VG-RNTI could be used to scramble the CRC bits of the SCI and/or could be used to initialize the scrambling sequence which will be used on the PSSCH rate matched bits. In an example, the scrambling sequence may be a gold sequence.

[0136] Examples involving feedback SCI are discussed herein. In an example, HARQ-ACK bits may be sent back from the receiver vehicle to the transmitter vehicle. The semi-static or dynamic HARQ-ACK codebook could be used. It is possible that the channel state information (CSI) may or may not be included in SCI. This feedback SCI may be sent over the PSCCH channel, the PSSCH channel or piggybacked on the PSSCH channel. The terms feedback SCI and sidelink feedback control information (SFCI) may be used interchangeably and remain consistent with the examples provided herein.

[0137] The CSI bits may be sent back from the receiver vehicle to the transmitter vehicle, together with the HARQ-ACK bits, in an example. In another example, the CSI bits may be sent alone from the receiver vehicle to the transmitter vehicle.

[0138] Examples polar coding procedures for V2X DCI are provided herein. Further, example DCI formats and mapping blocks may be used in the polar coding procedures.

[0139] FIG. 2 is an example diagram of a polar coding procedure for V2X DCIs or SCI. In an example shown in diagram 200, DCI format 3_0 or DCI format 3_1 may be used. Further, as shown in diagram 200, a payload mapping block 220 may provide a payload to a CRC attachment block 230, which may attach a CRC to the payload. The combined output of the CRC attachment block 230 may then undergo polar encoding at a polar encoding block 240. Further, the output of the polar encoding block 240 may be rated matched at a rate matching block 250, whose output may then in turn be scrambled at a scrambling block 260.

[0140] Further, payload mapping block 220 may be used for V2X DCI in an example shown in diagram 200. For example, in DCI format 3_0 or DCI format 3_1 , there may a field named zero-padding. This field may be used to match the payload size of DCI format 3_0 to that of DCI format 0_0. Also, this field may be used to match the payload size of DCI format 3_1 to that of DCI format 0_1. The zero-padding may be appended to the information bits in LTE. In NR, a polar code is used for DCI. The zero padding bits can be considered as known information which could be placed in the front bit channels of the information bit set. These zero padding bits could be treated as frozen bits at the polar decoder. This could improve the BLER performance as the effective code rate is reduced. These zero padding bits could also improve the decoding speed, as the decoding of these padding bits is not needed in the successive cancellation list decoding.

[0141] It is possible that the number of information bits is not a constant in V2X DCI.

Flence, the number of padding bits may not be a constant. It is possible to calculate the lower bound on the number of padding bits. Suppose that the lower bound is A, then only set A padding bits may be mapped to the front of the bit channels of the information bit set. The remaining padding bits could still be placed at the end of the information bits.

[0142] In an additional or alternative example scheme, all or part of the padding bits could be placed at the least reliable bit channels of the information bit set. This could improve the bit error rate (BER) of certain fields of V2X DCI. For example, the PSCCFI scheduling information could be placed at the most reliable bit channels in order for the scheduling information to be better protected.

[0143] It should be noted that the assignment of the padding bits in the natural front order or in the least reliable order of the bit channels should consider the interleaving pattern introduced by a distributed CRC scheme of polar coding. Specifically, an interleaving pattern known in LTE could be used, in an example.

[0144] FIG. 3 is an example diagram of DCI payload mapping. The detailed reordering may depend on the payload size, by taking into account the interleaving pattern in an example shown in diagram 300.

[0145] As shown in FIG. 3, a DCI payload may include a carrier indicator 320, BWP information 330, PSCCFI scheduling information 340, PSSCH scheduling information 350, and padding bits 360. The DCI payload bits may then undergo reordering to produce a reordered DCI payload 390, as shown in FIG. 3.

[0146] The 24 bits CRC may be generated for the reordered DCI payload 390, and interleaving may be applied on the CRC bits and payload bits, in an example. The last 16 bits of the CRC bits may be XOR-ed by SL-V-RNTI, SL-SPS-V-RNTI, SL-V-G-RNTI or SL-SPS-V-G-RNTI.

[0147] In an example, the interleaved and masked CRC and payload bits may be sent to the polar encoder, in which a fixed polar sequence may be used. In an example, the polar encoder may be in the polar encoding block 240. The polar encoded bits may be rate matched by using a circular buffer. In an example, the circular buffer rate matching may be in the rate matching block 250. The rate matched bits may be further scrambled by a scrambling sequence. The scrambling sequence may be a gold sequence which may be initialized by (SL-V-RNTI, SL-SPS-V-RNTI, SL-V- G-RNTI or SL-SPS-V-G-RNTI) and/or cell ID. In an example, the scrambling sequence may scramble the rate matched bits in scrambling block 260. An example formula for the initialization sequence of the NR DCI formats could be used as

Cini_t = 0 v77 2¹⁶ + n_ID) mod 2³¹ Equation 1 where the n_RNTI could be SL-V-RNTI, SL-SPS-V-RNTI, SL-V-G-RNTI or SL-SPS-V-G-RNTI, and n_ID could be the cell ID or PDCCH DMRS scrambling ID, if configured.

[0148] A polar coding procedure for V2X SCI is discussed in an example herein. For example, the procedure shown in FIG. 2 may be used for polar coding for V2X SCI. In the legacy SCI format or the new SCI format defined elsewhere herein, there may be a field named zeropadding or reserved information. This field is used to match the payload size of SCI to a fixed number, which may facilitate polar decoding. [0149] The zero padding or reserved bits can be considered as known information which could be placed in the front bit channels of the information bit set. These zero padding or reserved bits could be treated as frozen bits at the polar decoder. This could improve the BLER performance as the effective code rate is reduced. It could also improve the decoding speed, as the decoding of these padding bits are not needed in the polar code successive cancellation list decoding.

[0150] It is possible that the number of information bits is not a constant in V2X SCI.

Hence, the number of padding or reserved bits may not be a constant. It is possible to calculate the lower bound on the number of padding or reserved bits. Suppose that the lower bound is A, then one may only set A padding bits or reserved bits to the front of the bit channels of the information bit set. The remaining padding bits or reserved bits could still be placed at the end of the information bits.

[0151] In an additional or alternative example scheme, all or part of the padding or reserved bits could be placed at the least reliable bit channels of the information bit set. This could improve the BER of certain fields of the V2X SCI.

[0152] FIG. 4 is an example diagram of SCI payload mapping. The detailed reordering shown in an example in diagram 400 may depend on the payload size, by taking into account the interleaving pattern. In an example shown in FIG. 4, an SCI payload may include a priority field 420, a resource reservation field 430, a frequency resource location field 440, an MCS field 450 and padding or reserved bits 460. The SCI payload may then undergo reordering to produce a reordered SCI payload, as shown in FIG. 4.

[0153] In one example way, an 1 1 bits CRC will be generated for the re-ordered SCI payload. The 1 1 CRC bits may be XOR-ed by part of the SL-V-G-RNTI or SL-SPS-V-G-RNTI for example, if the SCI is for unicast or multicast. For example, the first or the last 11 bits of the SL-V-G- RNTI or SL-SPS-V-G-RNTI may be masked to the CRC bits.

[0154] In another example way, a 24 bits CRC will be generated for the re-ordered SCI payload. In an example, the last 16 CRC bits could be XOR-ed by the SL-V-G-RNTI or SL-SPS-V- G-RNTI or destination (group) ID for example, if the SCI is for unicast or multicast.

[0155] The masked CRC and payload bits may be sent to the polar encoder, in which a fixed polar sequence may be used. In an example, the polar encoder may be in the polar encoding block 240. The polar encoded bits may be rate matched by using a circular buffer. In an example, the circular buffer rate matching may be in the rate matching block 250. The rate matched bits may be further scrambled by a scrambling sequence. The scrambling sequence could be a gold sequence which may be initialized by an SL-V-RNTI, an SL-SPS-V-RNTI, an SL-V-G-RNTI, an SL- SPS-V-G-RNTI and/or a cell ID. In an example, the scrambling sequence may scramble the rate matched bits in scrambling block 260. For example, the initialization sequence could be

Cinit = n_RNTi 2⁹ + 510 Equation 2 where n_RNTI could be SL-V-RNTI, SL-SPS-V-RNTI, SL-V-G-RNTI or SL-SPS-V-G-RNTI of the destination vehicle. Here, the shift of 2⁹ may have the non-overlap of the n_RNTI and the cell ID with constant value of 510. If the physical cell ID is to identify more than 512 physical cells, the value of 510 could be increased and the shift of 2⁹ could be extended accordingly. Note that the constant could be some value other than 510 and the shift of n_RNTI could be adjusted accordingly.

[0156] Extensions to D2D-related DCI and SCI are described in examples herein. In LTE, the following information may be transmitted by means of DCI format 5: resource(s) for the PSCCH, which may be 6 bits; a TPC command for the PSCCH and the PSSCH, which may be 1 bit; a frequency hopping flag, which may be an SCI format 0 field; a resource block assignment and hopping resource allocation, which may be another SCI format 0 field; a time resource pattern, which may be yet another SCI format 0 field; and padding bits to match the payload size to DCI format 0.

[0157] Examples provided herein include a modified NR DCI format, for example, a format

4_0, which could be designed for the D2D-related PSCCH/PSSCH scheduling. Besides the existing contents in LTE DCI format 5, the modified NR DCI format could contain one more field: a bandwidth part indicator field. This field may contain the information regarding which BWP could be used for sidelink transmissions. Further, this field could be 0, 1 or 2 bits, depending on the system configurations of the BWP.

[0158] In LTE, the following information may be transmitted by means of SCI format 0: a frequency hopping flag, which may be 1 bit; a resource block assignment and hopping resource allocation field, which may be fiog₂ (/v¾ (/v¾ + i) / 2) | bits; a time resource pattern, which may be 7 bits; an MCS field, which may be 5 bits; a timing advance indication, which may be 1 1 bits; and a group destination ID, which may be 8 bits.

[0159] Besides the fields contained in LTE SCI format 0, the modified NR SCI format may contain one or more of the following modified or new fields. For example, a modified modulation and coding scheme field may contain the MCS index used for the PSSCH channel. Several MCS tables may be defined for eMBB and URLLC. The selection among different MCS tables may be configured by RRC configuration. The MCS index could be 5 bits, as for an eMBB case, or it could be 4 bits for some simplified MCS tables. The MCS index could be a different number of bits in other examples. [0160] A data indicator field may be used for the SCI to support unicast transmissions.

Further, this field may be used to indicate when new data is scheduled in the current PSSCH transmission. This field could be 1 bit of information.

[0161] Also, a HARQ process number field may be used for unicast based sidelink.

Accordingly, multiple HARQ processes could be supported. This HARQ process number field may identify which HARQ process the current PSSCH transmission belongs to. It is expected that the HARQ processes supported for NR D2D could be smaller than that in NR eMBB use cases, due to the latency requirement. Hence, the payload size for the HARQ process number could be less than 4 bits, for example, 1 bit, 2 bits or 3 bits.

[0162] In addition, a redundancy version field may be included because multiple RVs may be supported for the retransmission of the data. Although LDPC coding may be used for the data channel with up to 4 RVs, one could use only part of the number of RVs for sidelink transmissions. For example, only RV0 and RV2 may be used to obtain the best BLER performance. Or, only RV0 and RV3 may be used to obtain a self-decodable feature of each RV in case some transmissions are corrupted. Hence, the payload size for redundancy version could be 1 bit.

[0163] Moreover, a TPC command for scheduled PSSCH field may be included to provide the TPC command used for setting the power of the PSSCH. In an example, the field could be 2 bits.

[0164] In another example, a CBGTI field may be included to provide the CBGTI information for the current transmission. The CBGTI field may be a bitmap with a length of configured CBGs. The bit 0 may indicate the CBG is not contained in the current transmission, and the bit 1 may indicate the CBG is contained in the current transmission. It is possible that the set of the size of configured CBGs for sidelink communication could be a subset of the set of the size of configured CBGs for downlink/uplink communication. This is because the transport block size in sidelink communications could be less than that in downlink/uplink communications, and consequently, the total number of scheduled CBGs could be less in the sidelink case. For example, the configured CBGs could be {0, 2} or {0, 2, 4} or {0, 2, 4, 6}. Hence, the payload of CBGTI could be 0, 2, 4 or 6 bits.

[0165] In a further example, a sidelink assignment index field may be included to match the number of sidelink subframes with a PSCCH that are to be acknowledged. In other words, the value of the field may indicate the number of SL HARQ-ACK reports that is to be transmitted on the PSSCH or the PSCCH. [0166] In yet another example, a padding bits field may be included to match the payload of the modified SCI format to some fixed size. Moreover, the D2D-related DCI and SCI could follow a similar polar coding procedure as V2X-related DCI and SCI.

[0167] Examples of scrambling for a PSCCH, a PSSCH and a DMRS are described herein. Like in NR UL/DL and LTE V2X, the gold sequence of length-31 may be used for the scrambling of the PSCCH and PSSCH. In the following the gold sequence of length-31 may be used. Other sequences may also be applied. Examples below considerer the initialization values of the gold sequence or other possible sequences.

[0168] For sidelink unicast and groupcast, in an example, the physical layer destination ID may be known to both the transmitter and receiver, in the session establishment process. In an example, the physical layer destination ID may be a destination group ID. In another example, the destination ID may be used to replace destination group ID, as in the following. The destination ID could be between 8 bits and 16 bits. It could be equal to a receiving WTRU’s RNTI in the case of sidelink unicast. The destination ID length is assumed to be A bits in following example discussions.

[0169] For sidelink unicast and groupcast, the physical layer source ID may also be known to both the transmitter and receiver. The source ID could be between 8 bits and 16 bits. It could be equal to a transmitter WTRU’s RNTI. The source ID length is assumed to be C bits in following example discussions. The source ID length C may be equal to or may be different from the destination ID length A.

[0170] Example PSCCH scrambling is considered herein. If the single part SCI is applied, the SCI information may need to be known to all the other WTRUs, no matter if the transmission is broadcast, unicast or groupcast. This SCI information may be used for other WTRU’s resource selection. Hence, as in LTE V2X, the initialization value C_init for PSCCH scrambling could be a constant. In LTE, there are 504 possible physical layer cell IDs, and the C_init for the PSCCH is set as a constant larger than 504. In NR, there are 1008 possible physical layer cell IDs, and the C_init for PSCCH may be set as a constant larger than 1008. To restrict to 10 bits, C_init for PSCCH could be any value between 1008 and 1023. For example, we could set C_init = 1022.

[0171] If a two part SCI is applied, the first part SCI information may need to be known to all the other WTRUs for their resource selection. Hence, the scrambling sequence of first part SCI could have initialization value C_init set as any value between 1008 and 1023, for example, C_init = 1022. For sidelink broadcast, the second part SCI information may also need to be known to all the other WTRUs. Hence, C_init can be set as that for the first part SCI information.

[0172] For sidelink unicast and groupcast, the second part SCI information may need to be known to only the destination WTRUs for their PSSCH decoding. Hence, the scrambling sequence of the second part SCI could have initialization value C_init set as depending on the destination ID and/or source ID.

[0173] The initialization value C_init can be set as n_{dest ID} 2^31~A + B, where the value

B may be set as any constant values between 1008 and 1023, and the shift of 31 - A is aimed to avoid the overlap with B. For instance, if the destination ID length is A=8/10/16 bits, then the shift (31 -A) is 23/21/15 bits. The value of B may distinguish the NR sidelink transmissions from NR UL/DL transmissions where the last 10 bits of C_init are less than 1008. If we consider the destination ID for SL broadcast is all 0’s, then this C_init is a unified formula for SL broadcast, groupcast and unicast. Other examples of the initialization value C_init could be as follows.

Cjnit ^— ^dest_in Equation 3

Cinit

Equation 4 where the source ID length is C bits.

Cjnit

Equation 5 where the destination ID length is A bits.

[0174] Example PSSCH scrambling for broadcast sidelink is considered herein. In LTE

V2X, the CRC length of PSCCH is 16 bits. In NR V2X, the CRC length of PSCCH could be 24 bits. The usage of PSCCH CRC bits in the PSSCH scrambling could be still applied for broadcast sidelink, in consideration of the CRC length difference between LTE PSCCH and NR PSCCH.

[0175] In one example way, the initialization value for PSSCH scrambling sequence may be set as

Cjnit = ⁿio 2¹⁰ + B Equation 6 where the value B may be set as any constant values between 1008 and 1023.

[0176] FIG. 5 is an example diagram of initialization values of the scrambling sequence for broadcast sidelink. In an example shown in diagram 500, the length of n _D could be 21 bits. The n _D could be part 534 of the 24-bit PSCCH CRC. For example, n _D could be the last or the first 21 bits of the 24-bit PSCCH CRC. This is shown in an example in initialization value 530, which may also include constant 537.

[0177] In another example way shown in FIG. 5, the initialization value 540 for PSSCH scrambling sequence may be set as

Cjnit = ⁿ ' 2¹⁵ + n_ssf 2¹⁰ + B Equation 7 where the value B may be set as any constant value 547 between 1008 and 1023, n_ssf could be the (part of) slot index 546 of the radio frame, n _D could be 16 bits and could be part 544 of the 24-bit PSCCH CRC. For example, n _D could be the last or the first 16 bits of the 24-bit PSCCH CRC. In case of subcarrier spacing (SCS) less than or equal to 30 kHz, the n_ssf is the full slot index of the radio frame. In case of SCS larger than 30 kHz, the n_ssf could be the first or the last 5 bits of the slot index of the radio frame.

[0178] In yet another example way, the initialization value 550 for PSSCH scrambling sequence may be set as

Cinit = ⁿio ' 2^31-A + B Equation 8 where the value B may be set as any constant value 557 between 1008 and 1023, and the n _D could be part 554 of the 24-bit PSCCH CRC. In an example, the part may be the last or the first A bits of the PSCCH CRC. For example, if the destination ID length is equal to A =8/10/16 bits, then the shift (31 - A) is equal to 23/21/15. For the example cases of A=8 bits or >1=10 bits, the destination ID could be part of the full physical layer destination ID. This length is for a unified design for sidelink unicast, groupcast and broadcast. In other words, the n_/Dis set to the destination ID for the sidelink unicast or groupcast, or set to the part of the CRC bits for the sidelink broadcast. Further, initialization value 550 may include zeros 555 and shows an example of A = 16.

[0179] PSSCH scrambling of groupcast or unicast sidelink are discussed in examples herein. Such scrambling may be dependent on the destination ID. For broadcast sidelink, the association between PSSCH and PSCCH may be enhanced by applying the PSCCH CRC bits for the scrambling sequence of PSSCH. For unicast or groupcast sidelink, the association between PSSCH and PSCCH may be via the usage of a destination ID.

[0180] FIG. 6 is an example diagram of initialization values of the scrambling sequence for unicast or groupcast sidelink that depend on the destination ID. In one example way shown in diagram 600, the initialization value may be set as

Cinit = n_dest_ID 2^31-A + B Equation 9 where the value B may be set as any constant values between 1008 and 1023, and the n_destlD is the destination ID. Initialization value 630 of FIG. 6 shows an example of A = 16 and may include destination ID 639, zeros 635 and constant 637. Also, initialization value 640 shows and example of A = 8 and may include destination ID 649, zeros 645 and constant 64 7.

[0181] Scrambling may also depend on both destination ID and a PSCCH CRC, in a further example. If the unified scrambling design for sidelink unicast/groupcast and sidelink broadcast is not necessary, then the initialization value for sidelink unicast/groupcast could depend on both destination ID and PSCCH CRC bits. In this case, the constant value B in the above formulas may not be used, and could be replaced by destination ID. [0182] FIG. 7 is an example diagram of initialization values of the scrambling sequence for unicast or groupcast sidelink that depend on both the destination ID and the PSCCH CRC. In one example way shown in diagram 700, initialization value 730 may be set as C_init = nf_D 2^A + ⁿ _des_tID< where the shift A may be the destination ID length for sidelink unicast and groupcast, and the nf_D could be part 734 of the 24-bit PSCCH CRC. For example, the part 734 may be the last or the first (31 - A) bits of the PSCCH CRC. Further, the initialization value 730 may include destination ID 739.

[0183] In another example way shown in FIG. 7, the initialization value 740 may be set as

Cini_t = ⁿ _des_{tID '} 2^31~A + nf_D. Further, initialization value 740 may similarly include destination ID length 749 and part 744 of the 24-bit PSCCH CRC.

[0184] Scrambling may also depend on both destination ID and source ID, in an additional example. The initialization value for sidelink unicast/groupcast could depend on both destination ID and source ID.

[0185] FIG. 8 is an example diagram of initialization values of the scrambling sequence for unicast or groupscast sidelink that on both destination ID and source ID. In one example way shown in diagram 700, the initialization value 830 may be set as C_init = n_sourcew 2^31~c + n_destw, where the C may be the source ID length for sidelink unicast and groupcast.

[0186] As seen in FIG. 8, initialization value 830 may include source ID 832, zeros 835 and destination ID 839. In case both source ID length and the destination ID length are equal to 16 bits, then the initialization value may be set as C_init = ( n_sourcew 2¹⁶ + n_dest[D) mod 2³¹.

[0187] In another example way shown in FIG. 8, the initialization value 840 may be set as

Cini_t = ⁿ _des_{tID '} 2^31~A + n_sourcew, where the A may be the destination ID length for sidelink unicast and groupcast. As seen in FIG. 8, initialization value 840 may include destination ID 849, zeros 845 and source ID 842. In an example case where both the source ID length and the destination ID length are equal to 16 bits, then the initialization value may be set as C_init =

[0188] Scrambling may also depend on destination ID, source ID and PSCCH CRC, in an additional example. The initialization value for sidelink unicast/groupcast could depend on destination ID, source ID and PSCCH CRC.

[0189] FIG. 9 is an example diagram of initialization values of the scrambling sequence for unicast or groupcast sidelink that depend on destination ID, source ID, and PSCCH CRC. In one example way shown in diagram 900, the initialization value 930 may be set as C_init = n_sourceiD 2^31~C + nf_D 2^A + n_destw, where A may be the destination ID length, C may be the source ID length, and nf_D is part of PSCCH CRC with length (31 - A - C). Accordingly, as shown in FIG. 9, initialization value 930 may include source ID 932, part of PSCCH CRC 934 and destination ID 939.

[0190] In another example way shown in FIG. 9, the initialization value 940 may be set as

Cinit = n_destID 2^31~A + nf_D 2^C + n_sourcew, where A may be the destination ID length, C may be the source ID length, and nf_D is part of PSCCH CRC with length (31 - A - C). In this way, as shown in FIG. 9, initialization value 940 may include destination ID 949, part of PSCCH CRC 944 and source ID 942.

[0191] Moreover, unified procedures for setting initialization value for unicast, groupcast and broadcast PSSCH scrambling are discussed in examples herein. The initialization value setting for the PSSCH scrambling sequence could follow a unified procedure for unicast, groupcast and broadcast.

[0192] FIG. 10 is a flow diagram of a procedure for setting the initialization values for a

PSSCH scrambling sequence. An exemplary procedure as shown in flow diagram 1000 may include first a WTRU setting 1020 the 10 last bits, or least significant bits (LSBs), of C_init as a constant between 1008 and 1023. The WTRU may then determine 1030 if the sidelink transmission is for unicast or groupcast on the one hand, or for broadcast on the other hand. If the sidelink transmission is for unicast or groupcast, the WTRU may set 1070 the destination ID to the A first bits, or most significant bits (MSBs), of C_init. If the sidelink transmission is for broadcast, the WTRU may set 1050 the A first bits, or MSBs, of C_init as the last A PSCCH CRC bits. In an example, the WTRU may equalize a PSCCH CRC in the broadcast case to the destination ID in the unicast/groupcast case. Further, the WTRU may finalize C_init 1080.

[0193] FIG. 1 1 is another flow diagram of a procedure for setting the initialization values for a PSSCH scrambling sequence. An exemplary procedure as shown in flow diagram 1 100 may include the WTRU determining 1 130 if the sidelink transmission is for unicast or groupcast on the one hand, or for broadcast on the other hand. Specifically, if the sidelink transmission is for unicast or groupcast, the WTRU may set 1 160 the C last bits, or LSBs, of C_init as a source ID. If the sidelink transmission is for broadcast, the WTRU may set 1 140 the C last bits, or LSBs, of C_init as the last C PSCCH CRC bits. If the sidelink transmission is for unicast or groupcast, the WTRU may set 1 170 the destination ID to the A first bits, or MSBs, of C_init. Otherwise, the WTRU may set 1150 the A first bits, or MSBs, of C_init as a constant. This scheme may equalize PSCCH CRC in the broadcast case to source ID in the unicast/groupcast case, and may equalizes the destination ID in the unicast/groupcast case to a constant in the broadcast case. Further, the WTRU may finalize [0194] Examples of PSCCH and PSSCH DMRS scrambling are disclosed herein. In an example, the PSCCH DMRS scrambling sequence could be a gold sequence with C_init set to Cini_t = (2¹⁷ (l4 ri_gj + l + l)(2 N_w + 1) + 2 N_ID)mod 2³¹, where l is the OFDM symbol number within the slot,

is the slot number within a frame, and N_w is a constant. The length of N_ID may 16 bits. In an example, the N_w could be all zeros or all ones. In another example,

[0195] In another example, the PSSCH DMRS scrambling sequence could be a gold sequence with C_init set t

2³¹, where l is the OFDM symbol number within the slot,

is the slot number within a frame, and N_w is a constant for broadcast sidelink or is equal to the destination ID, or PSSCH DMRS scrambling ID or (part of) PSCCH CRC bits.

[0196] FIG. 12 is a flow diagram of an example process for a sidelink WTRU transmitter to process a control channel and a data channel. In an example shown in flow diagram 1200 with one or more SCI payloads, a WTRU may first reorder 1210 the one or more SCI payloads by prepending partial zeros to the front. In an example, the WTRU may be a transmitting WTRU. In another example, the WTRU may be a source WTRU. In a further example, the WTRU may be an originating WTRU. Further, the prepending may be a rule-based zeros prepending, in an example.

[0197] Moreover, the WTRU may apply priority-based polar code bit channel mappings as part of the payload reordering 1210. Also, the reordered SCI payloads may be used to generate CRC bits, which may be attached 1215 to the reordered payload. In a further example, an optional CRC mask may be applied using the RNTI, the destination ID, the destination group ID or the source ID. In an example, the last 16 CRC bits may be masked with the RNTI of a destination WTRU, the destination ID of the destination WTRU, the destination group ID of the destination WTRUs, or the source ID of the source WTRU. In another example, the last 16 CRC bits may be masked with the RNTI of a receiving WTRU, the destination ID of the receiving WTRU, the destination group ID of the receiving WTRUs, or the source ID of the transmitting WTRU. Further details are provided other examples disclosed elsewhere herein.

[0198] The reordered payload and CRC bits may then be encoded by polar coding and rate matching may be applied on the polar coded bits 1230. The rate matching output bits may be scrambled 1250 with a scrambling sequence. In an example, the scrambling sequence may be an SCI scrambling sequence. Further, the SCI scrambling sequence may be based on an SCI initialization value. In an example, the SCI initialization value may be an SCI scrambling sequence initialization value. Moreover, the SCI initialization value may include at least one of a full SCI CRC, a partial SCI CRC, the RNTI, the destination ID, a source ID or an SCI scrambling constant. In an example, the SCI scrambling constant may have a value of between 1008 and 1023. In another example, the full CRC or the partial CRC may include PSCCH CRC bits. Further details may be provided in other examples disclosed elsewhere herein.

[0199] In examples, the scrambling sequence could be a gold sequence provided by a gold sequence generator. The initialization value for the scrambling sequence may be based on one or both of the RNTI or the destination ID, in examples. For example, a bit-wise concatenation of the destination ID and a scrambling constant may be used. In an example, this bit-wise concatenation may be used for an SL broadcast. Additionally, the scrambling sequence may undergo an exclusive disjunction, or be XOR’d, with the rate matching output bits.

[0200] Moreover, the scrambled SCI payload bits may be modulated 1270 and mapped

1290 to resources for a channel for transmission. In an example, the channel may be a control channel, such as a control channel used in SL communication. For example, the channel may be a PSCCH. In another example, the channel may be a D2D channel, such as a D2D control channel. In a further example, the channel may be a ProSe channel, such as a ProSe control channel. In an additional example, the channel may be a relay channel, such as a relay control channel. In yet a further example, the channel may be a data channel, such as a data channel used in SL communication. For example, the channel may be a PSSCH. In an additional example, the channel may be a D2D data channel. In yet another example, the channel may be a ProSe data channel. In yet an additional example, the channel may be a relay data channel.

[0201] In an additional example, data for a data channel may be used to generated CRC bits which may be attached 1220 to the data. Attaching CRC bits to the data 1220 may also be referred to as appending CRC bits to the data, in an example. Also, then the data with CRC bits may be encoded by LDPC codes 1225. In an example, the data channel may be an SL channel. For example, the channel may be a PSSCH. Further, the data may be SL data. For example, the data may be PSSCH data.

[0202] In an example, the encoded bits may be rate matched 1240 using SCI payloads, for example, one or more of an MCS, an RV, a HARQ process number, a new data indicator (NDI) or a CBGTI. The MCS may determine the number of bits selected from the circular buffer storing the LDPC encoded bits. The RV may determine the starting position of the bits to be selected from the circular buffer storing the LDPC encoded bits. The HARQ process number, NDI, and CBGTI may determine the circular buffer to be used.

[0203] The rate matched bits may be scrambled 1260 with a scrambling sequence. In an example, the scrambling sequence may be a data scrambling sequence. Further, the data scrambling sequence may be based on a data initialization value. In an example, the data initialization value may be a data scrambling sequence initialization value. Moreover, the data initialization value may include at least one of the destination ID, a full CRC , a partial CRC, a data scrambling constant and the source ID. In an example, the full CRC or the partial CRC may include PSCCH CRC bits. In another example, the data scrambling constant may have a value of between 1008 and 1023. Further details may be provided in other examples disclosed herein. Further, the scrambling operation could be different between broadcast sidelink and unicast/groupcast sidelink.

[0204] In examples, the scrambling sequence could be a gold sequence provided by a gold sequence generator. The initialization value for the scrambling sequence may be based on one or more of the destination ID, the source ID, or the SCI CRC, in examples. For example, a bit-wise concatenation of the destination ID, the source ID, a full SCI CRC, a partial SCI CRC and/or a scrambling constant may be used. In an example, this bit-wise concatenation may be used for an SL broadcast. Additionally, the scrambling sequence may undergo an exclusive disjunction, or be XOR’d, with the rate matching output bits.

[0205] The scrambled bits may be modulated 1280 and then mapped 1295 to resources for the data channel. In an example, the data channel may be an SL channel. For example, the channel may be a PSSCH. In another example, the channel may be a D2D channel, such as a D2D data channel. In a further example, the channel may be a ProSe channel, such as a ProSe data channel. In an additional example, the channel may be a relay channel, such as a relay data channel. One or both of the resources in the frequency domain and the resources in the time domain may be indicated in the SCI, where cross-slot resource allocation is allowed. Further details are provided in other examples disclosed elsewhere herein.

[0206] FIG. 13 is a flow diagram of an example process for a sidelink WTRU receiver to process a control channel and a data channel. For a given channel resource, a WTRU may first demap the channel resource 1310 to obtain modulation symbols for a received payload, as shown in an example in flow diagram 1300. In an example, the WTRU may be a receiving WTRU. In another example, the WTRU may be a destination WTRU. In an example, the channel resource may be a control channel resource, such as a control channel resource used in SL communication. For example, the channel resource may be a PSCCH resource. In a further example, the received payload may be a received SCI payload. The WTRU may then apply demodulation 1330 to the received payload. The demouldated bits may then be descrambled 1350 with a scrambling sequence by the WTRU. In a further example, the scrambling sequence may be an SCI scrambling sequence. Further, the SCI scrambling sequence may be based on an SCI initialization value. In an example, the SCI initialization value may be an SCI scrambling sequence initialization value. Moreover, the SCI initialization value may include at least one of a full SCI CRC, a partial SCI CRC, an SCI scrambling constant, an RNTI of the destination WTRU, a destination ID of the receiving WTRU, an RNTI of the transmitting WTRU or a source ID of the transmitting WTRU. In an example, the SCI scrambling constant may have a value of between 1008 and 1023. In another example, the full CRC or the partial CRC may include PSCCH CRC bits. Further, the source ID may be based on data for transmission from the transmitting WTRU over certain data links. Accordingly, the transmitting WTRU may relate to multiple source IDs. Further details may be provided in other examples disclosed herein.

[0207] The descrambling 1350 may involve a channel being descrambled. In an example, the channel may be a control channel, such as a control channel used in SL communication. For example, the channel may be a PSCCFI.

[0208] The descrambled bits may then be rate dematched and polar decoded 1370.

Further, a CRC demask, check and removal may be applied to the polar decoded bits 1375. If the CRC check is passed, the SCI payloads may be reordered and detected 1390.

[0209] In an example, a receiving WTRU may receive a sidelink data message from the transmitting WTRU. Based on the SCI payloads, a data channel could be decoded. In an example, the data channel may be an SL channel. For example, the channel may be a PSSCH. Based on decoded SCI fields of frequency resource location and time duration for data channel, one or more data channel resources may be demapped 1320 and the modulation symbols may be obtained by the receiving WTRU, in an example. The demapping of the one or more data channel resources may be based on on a decoded SCI field of time duration for PSSCH transmission. With the decoded SCI fields of MCS, demodulation 1340 may be performed by the receiving WTRU. The demodulated bits may then be descrambled 1360 by the receiving WTRU with a scrambling sequence based on a data initialization value. In an example, the data initialization value may be a data scrambling sequence initialization value. In a further example, the data initialization value may include at least one of of a source ID, a full SCI CRC, a partial SCI CRC, a destination ID or a data scrambling constant. In an example, the full CRC or the partial CRC may include PSCCH CRC bits. In a further example, the data scrambling constant may have a value of between 1008 and 1023. For example, the demodulated bits may then be descrambled 1360 with a scrambling sequence based on one or more of the RNTI of the destination WTRU, the destination ID of destination WTRU, the source ID of the source WTRU or the PSCCH CRC. Further details may be provided in other examples disclosed herein.

[0210] The descrambling 1360 may involve the data channel being descrambled. In an example, the data channel may be an SL channel. For example, the channel may be a PSSCH. [021 1] The descrambled sidelink data bits may be rate dematched 1365, using the decoded RV, MCS, HARQ process number, NDI and CBGTI. The HARQ process number, NDI and CBGTI may indicate which circular buffer is used for combining. The RV and MCS may indicate which portion of LDPC coded bits are used for combining. The rate dematched bits may be decoded using an LDPC code 1380. A CRC check and removal may be applied on the LDPC decoded bits 1385. In example cases of unicast or groupcast sidelink transmissions where feedback is required, then HARQ-ACK feedback and optional CSI feedback may be sent back 1395, as is described in other examples disclosed herein.

[0212] Although the solutions described herein consider New Radio (NR), 5G or LTE, LTE-

A specific protocols, it is understood that the solutions described herein are not restricted to this scenario and are applicable to other wireless systems as well.

[0213] Although features and elements are described above in particular combinations, one of ordinary skill in the art will appreciate that each feature or element can be used alone or in any combination with the other features and elements. In addition, the methods described herein may be implemented in a computer program, software, or firmware incorporated in a computer- readable medium for execution by a computer or processor. Examples of computer-readable media include electronic signals (transmitted over wired or wireless connections) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, a read only memory (ROM), a random access memory (RAM), a register, cache memory, semiconductor memory devices, magnetic media such as internal hard disks and removable disks, magneto-optical media, and optical media such as CD-ROM disks, and digital versatile disks

(DVDs). A processor in association with software may be used to implement a radio frequency transceiver for use in a WTRU, UE, terminal, base station, RNC, or any host computer.

Claims

CLAIMS What is claimed:

1. A method for a transmitting wireless transmit/receive unit (WTRU) to transmit sidelink data, the method comprising:

generating and attaching cyclic redundancy check (CRC) bits to sidelink data;

low-density parity check (LDPC) encoding and rate matching the sidelink data and the CRC bits attached to the sidelink data;

scrambling the rate matched sidelink data with a data scrambling sequence, wherein the data scrambling sequence is based on at least a source identifier (ID);

modulating the scrambled sidelink data to generate a sidelink data message; and transmitting the sidelink data message to a receiving WTRU.

2. The method of claim 1 , wherein the data scrambling sequence is further based on a data scrambling sequence initialization value; wherein the data scrambling sequence initialization value includes at least one of the source ID, a full sidelink control information (SCI) CRC, a partial SCI CRC, a destination ID or a data scrambling constant; and wherein the data scrambling constant has a value of between 1008 and 1023.

3. The method of claim 1 , wherein the sidelink data message is transmitted over a sidelink data channel.

4. The method of claim 3, further comprising:

receiving a feedback SCI message from the receiving WTRU, wherein the feedback SCI message includes at least one of HARQ feedback or channel state information (CSI) feedback; wherein the sidelink data channel is a physical sidelink shared channel (PSSCH); and wherein the feedback SCI message is at least one of received over the PSSCH or received piggybacked on the PSSCH.

5. The method of claim 2, wherein the receiving WTRU is part of a group of receiving WTRUs and destination ID is a destination group ID.

6. The method of claim 1 , further comprising:

reordering SCI payload bits;

generating and attaching CRC bits to the reordered SCI payload bits;

polar encoding and rate matching the reordered SCI payload bits and the CRC bits attached to the SCI payload;

scrambling the rate matched SCI payload bits with an SCI scrambling sequence;

modulating the scrambled SCI payload bits to generate an SCI message; and

transmitting the generated SCI message to the receiving WTRU.

7. The method of claim 6, wherein the SCI scrambling sequence is based on an SCI scrambling sequence initialization value; wherein the SCI scrambling sequence initialization value includes at least one of a full SCI CRC, a partial SCI CRC, a destination ID, a source ID, a radio network temporary identifier (RNTI) or an SCI scrambling constant; and wherein the SCI scrambling constant has a value of between 1008 and 1023.

8. The method of claim 6, wherein the SCI payload includes at least one of a frequency resource location of the current transmission field, a modulation and coding scheme field, a new data indicator field, a hybrid automatic repeat request (HARQ) process number field, a redundancy version field, a transmit power control (TPC) command field, a Code Block Group Transmission Information (CBGTI) field, a sidelink assignment index field, or a time duration for PSSCH transmission field.

9. The method of claim 6, wherein the SCI message is transmitted over a sidelink control channel; and wherein the sidelink data and the SCI message are transmitted as part of at least one of a unicast transmission or a groupcast transmission.

10. The method of claim 9, wherein the sidelink control channel is a physical sidelink control channel (PSCCH) and a feedback SCI message is received from the receiving WTRU over the PSCCH.

1 1. A method for a receiving wireless transmit/receive unit (WTRU) to receive sidelink data, the method comprising:

receiving a sidelink data message from a transmitting WTRU;

demapping one or more data channel resources of a sidelink data channel to obtain modulation symbols, based on a decoded sidelink control information (SCI) field of time duration for physical sidelink shared channel (PSSCH) transmission;

demodulating sidelink data from the received sidelink data message based on the modulation symbols, wherein the modulation symbols are based on one or more decoded SCI modulation and coding scheme (MCS) fields;

descrambling the demodulated sidelink data with a data scrambling sequence, wherein the data scrambling sequence is based on at least a source identifier (ID);

rate dematching the descrambled sidelink data and cyclic redundancy check (CRC) bits attached to the descrambled sidelink data;

low-density parity check (LDPC) decoding the rate dematched sidelink data and CRC bits attached to the descrambled sidelink data; and

performing a CRC check on and removing the CRC bits attached to the descrambled sidelink data.

12. The method of claim 1 1 , wherein the data scrambling sequence is further based on a data scrambling sequence initialization value; wherein the data scrambling sequence initialization value includes at least one of the source ID, a full sidelink control information (SCI) CRC, a partial SCI CRC, a destination ID or a data scrambling constant; and wherein the data scrambling constant has a value of between 1008 and 1023.

13. The method of claim 1 1 , wherein the sidelink data message is received over the sidelink data channel.

14. The method of claim 13, further comprising:

transmitting a feedback SCI message to the transmitting WTRU, wherein the feedback SCI message includes at least one of HARQ feedback or channel state information (CSI) feedback, wherein the sidelink data channel is a PSSCH and wherein the feedback SCI message is at least one of transmitted over the PSSCH or transmitted piggybacked on the PSSCH.

15. The method of claim 12, wherein the receiving WTRU is part of a group of receiving WTRUs and destination ID is a destination group ID.

16. The method of claim 1 1 , further comprising.

receiving an SCI message from a transmitting WTRU;

demapping one or more control channel resources of a sidelink control channel to obtain modulation symbols;

demodulating SCI payload bits from the received SCI message based on the modulation symbols;

descrambling the demodulated SCI payload bits with an SCI scrambling sequence;

rate dematching and polar decoding the descrambled SCI payload bits and CRC bits attached to the descrambled SCI payload bits;

performing a CRC demask and check on and removing the CRC bits attached to the descrambled SCI payload bits; and

on a condition that the CRC check is passed, reordering the checked SCI payload bits.

17. The method of claim 16, wherein the SCI scrambling sequence is based on an SCI scrambling sequence initialization value; wherein the SCI scrambling sequence initialization value includes at least one of a full SCI CRC, a partial SCI CRC, a destination ID, a source ID, a radio network temporary identifier (RNTI) or an SCI scrambling constant; and wherein the SCI scrambling constant has a value of between 1008 and 1023.

18. The method of claim 16, wherein the SCI payload includes at least one of a frequency resource location of the current transmission field, a modulation and coding scheme field, a new data indicator field, a hybrid automatic repeat request (HARQ) process number field, a redundancy version field, a transmit power control (TPC) command field, a Code Block Group Transmission Information (CBGTI) field, a sidelink assignment index field, or a time duration for PSSCH transmission field.

19. The method of claim 16, wherein the SCI message is received over the sidelink control channel; and wherein the sidelink data and the SCI message are received as part of at least one of a unicast transmission or a groupcast transmission.

20. The method of claim 19, wherein the sidelink control channel is a physical sidelink control channel (PSCCH) and a feedback SCI message is transmitted to the transmitting WTRU over the PSCCH.