Enabling / disabling HARQ feedback for multiple transport blocks scheduled by a single DCI

Abstract

A method for Hybrid Automatic Repeat Request (HARQ) feedback in a non-terrestrial network includes receiving, by a user equipment (UE), configuration parameters indicating whether HARQ feedback is enabled or disabled for a first HARQ process number and a second HARQ process number, respectively; receiving downlink control information (DCI) including scheduling information for a first transport block (TB) associated with the first HARQ process number and a second TB associated with the second HARQ process number, wherein the DCI indicates one of enabling the HARQ feedback or disabling the HARQ feedback; and enabling or disabling the HARQ feedback for the first TB and the second TB, wherein the enabling or disabling of the HARQ feedback for at least one of the first TB and the second TB is based on an indicator in the DCI, regardless of an indicator in the configuration parameters.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority under 35 U.S.C. §119(e) from U.S. Provisional Patent Application No. 63 / 430,830, filed December 7, 2022 (the "Provisional Application"), the contents of which are incorporated herein by reference. [Background technology]

[0002] The present invention is directed to 5G, the fifth generation mobile network, which is the new global wireless standard that follows 1G, 2G, 3G, and 4G networks. 5G enables networks designed to connect machines, objects, and devices.

[0003] The present invention is particularly directed to enabling / disabling HARQ feedback, including improvements to existing solutions when Downlink Control Information (DCI) schedules multiple downlink Transport Blocks (TBs) (e.g., DCI for multiple TB scheduling, DCI for Semi-Persistent Scheduling (SPS) activation, etc.) Exemplary embodiments provide improvements to existing solutions when DCI schedules multiple downlink TBs (e.g., DCI for multiple TB scheduling, DCI for SPS activation, etc.). Summary of the Invention

[0004] In an embodiment, the present invention provides a method for Hybrid Automatic Repeat Request (HARQ) feedback in a non-terrestrial network, the method including receiving, by a user equipment (UE), configuration parameters indicating whether HARQ feedback is enabled or disabled for a first HARQ process number and a second HARQ process number, respectively. The method includes receiving downlink control information (DCI) including scheduling information for a first transport block (TB) associated with the first HARQ process number and a second TB associated with the second HARQ process number, the DCI indicating one of enabling HARQ feedback or disabling HARQ feedback, and enabling or disabling HARQ feedback for the first TB and the second TB, wherein the enabling or disabling of HARQ feedback for at least one of the first TB and the second TB is based on an indicator in the DCI, regardless of an indicator in the configuration parameters.

[0005] A first hybrid automatic repeat request (HARQ) process number and a second HARQ process number may be associated with a first cell, and a first transport block (TB) and a second TB may be scheduled to be received via the first cell. The first hybrid automatic repeat request (HARQ) process number may be associated with the first cell, and a second HARQ process number may be associated with a second cell, and the first transport block (TB) may be scheduled to be received via the first cell, and the second TB is scheduled to be received via the second cell. Downlink control information (DCI) may include a field including a value indicating one of enabling hybrid automatic repeat request (HARQ) feedback and disabling HARQ feedback. The field may include a first bit, and the value of the first bit indicates one of enabling hybrid automatic repeat request (HARQ) feedback and disabling HARQ feedback.

[0006] A value of 1 for the first bit may indicate enabling of hybrid automatic repeat request (HARQ) feedback, and a value of 0 for the first bit may indicate disabling of HARQ feedback. Downlink control information (DCI) may indicate a configuration parameter override. Enabling or disabling of hybrid automatic repeat request (HARQ) feedback for both the first transport block (TB) and the second TB may be based on an indicator in the downlink control information (DCI), regardless of an indicator in the configuration parameter. Enabling or disabling of hybrid automatic repeat request (HARQ) feedback for one of the first transport block (TB) and the second TB may be based on an indicator in the downlink control information (DCI), regardless of an indicator in the configuration parameter. Enabling or disabling of hybrid automatic repeat request (HARQ) feedback for an earlier scheduled TB between the first transport block (TB) and the second TB may be based on an indicator in the downlink control information (DCI), regardless of an indicator in the configuration parameter.

[0007] Enabling or disabling hybrid automatic repeat request (HARQ) feedback for the other transport block may be based on an indication by a configuration parameter. Transmission of at least one of the first hybrid automatic repeat request (HARQ) feedback associated with the first transport block (TB) and the second HARQ feedback associated with the second TB is preferably based on enabling HARQ feedback for at least one of the first TB and the second TB in response to receiving downlink control information (DCI). The downlink control information (DCI) is for activating a semi-persistent scheduling (SPS) configuration. Furthermore, the method may include receiving SPS configuration parameters for the semi-persistent scheduling (SPS) configuration. The first transport block (TB) and the second TB may be associated with the semi-persistent scheduling (SPS) configuration.

[0008] The method may include receiving a first transport block (TB) and a second TB. In that case, the configuration parameters may indicate a bit string including a first bit and a second bit, where the first bit may be associated with a first hybrid automatic repeat request (HARQ) process number and the second bit may be associated with a second HARQ process number, and values ​​of the first bit and the second bit may indicate whether HARQ feedback for the first HARQ process number and the second HARQ process number is enabled or disabled, respectively. The configuration parameters may be radio resource control (RRC) configuration parameters. The configuration parameters may include a first parameter indicating that overriding of hybrid automatic repeat request (HARQ) feedback by downlink control information (DCI) is enabled. The configuration parameters may include a first parameter indicating the presence of at least one field for enabling hybrid automatic repeat request (HARQ) feedback or disabling HARQ feedback in the scheduling downlink control information (DCI).

[0009] In an embodiment, the present invention provides a method for Hybrid Automatic Repeat Request (HARQ) feedback in a non-terrestrial network, the method including: receiving, by a user equipment (UE), configuration parameters indicating whether HARQ feedback is enabled or disabled for a first HARQ process number and a second HARQ process number, respectively; receiving downlink control information (DCI) including scheduling information for a first transport block (TB) associated with the first HARQ process number and a second TB associated with the second HARQ process number; indicating whether HARQ feedback is enabled or disabled for the first TB; indicating whether HARQ feedback is enabled or disabled for the second TB; enabling or disabling HARQ feedback for the first TB based on an indicator in the DCI regardless of an indicator in the configuration parameters; and enabling or disabling HARQ feedback for the second TB based on an indicator in the DCI regardless of an indicator in the configuration parameters.

[0010] The first hybrid automatic repeat request (HARQ) process number and the second HARQ process number may be associated with a first cell, and the first transport block (TB) and the second TB may be scheduled to be received via the first cell. The first hybrid automatic repeat request (HARQ) process number may be associated with the first cell, and the second HARQ process number may be associated with a second cell, and the first transport block (TB) may be scheduled to be received via the first cell, and the second TB may be scheduled to be received via the second cell. Downlink control information (DCI) may include a first field including a first value indicating one of enabling hybrid automatic repeat request (HARQ) feedback or disabling HARQ feedback for the first transport block (TB), and a second field including a second value indicating one of enabling HARQ feedback or disabling HARQ feedback for the second TB.

[0011] The first field may include a first bit, a value of which indicates one of enabling hybrid automatic repeat request (HARQ) feedback or disabling HARQ feedback for the first transport block (TB), and the second field may include a second bit, a value of which indicates one of enabling HARQ feedback or disabling HARQ feedback for the second TB. A 1 value of the first bit may indicate enabling hybrid automatic repeat request (HARQ) feedback for the first transport block (TB), and a 0 value of the first bit may indicate disabling HARQ feedback for the first TB. A 1 value of the second bit may indicate enabling hybrid automatic repeat request (HARQ) feedback for the second transport block (TB), and a 0 value of the second bit may indicate disabling HARQ feedback for the second TB.

[0012] The downlink control information (DCI) may indicate a configuration parameter override. And, the method may also include, in response to receiving the downlink control information (DCI), transmitting at least one of a first hybrid automatic repeat request (HARQ) feedback associated with the first transport block (TB) and a second HARQ feedback associated with the second TB based on whether HARQ feedback is enabled or disabled for the first transport block (TB) and the second TB. The downlink control information (DCI) may be for activating a semi-persistent scheduling (SPS) configuration. The method may also include receiving SPS configuration parameters for the semi-persistent scheduling (SPS) configuration. The first transport block (TB) and the second TB are associated with the semi-persistent scheduling (SPS) configuration.

[0013] The method of the present invention may also include receiving a first transport block (TB) and a second TB. The configuration parameter may indicate a bit string including a first bit and a second bit, where the first bit may be associated with a first hybrid automatic repeat request (HARQ) process number and the second bit is associated with a second HARQ process number, and values ​​of the first bit and the second bit may indicate whether HARQ feedback is enabled or disabled for the first HARQ process number and the second HARQ process number, respectively. The configuration parameter may be a radio resource control (RRC) configuration parameter. The configuration parameter may include a first parameter indicating that overriding of hybrid automatic repeat request (HARQ) feedback by downlink control information (DCI) is enabled. And, the configuration parameter may include a first parameter indicating the presence of at least one field for enabling hybrid automatic repeat request (HARQ) feedback or disabling HARQ feedback in the scheduling downlink control information (DCI). [Brief explanation of the drawings]

[0014] [Figure 1] 1 illustrates an example of a mobile communication system in accordance with some aspects of various exemplary embodiments of the present disclosure. [Figure 2A] 1 illustrates an example of a user plane radio protocol stack in accordance with some aspects of various exemplary embodiments of the present disclosure. [Figure 2B] 1 illustrates an example of a control plane radio protocol stack in accordance with some aspects of various exemplary embodiments of the present disclosure. [Figure 3A] 1 illustrates an example mapping between logical channels and transport channels in the downlink in accordance with some aspects of various example embodiments of the present disclosure. [Figure 3B] 1 illustrates an example mapping between logical channels and transport channels in the uplink in accordance with some aspects of various example embodiments of the present disclosure. [Figure 3C] 1 illustrates an example mapping between logical channels and transport channels in a sidelink in accordance with some aspects of various example embodiments of the present disclosure. [Figure 4A] 1 illustrates an example mapping between transport channels and physical channels in the downlink in accordance with some aspects of various example embodiments of the present disclosure. [Figure 4B] 1 illustrates an example mapping between transport channels and physical channels in the uplink in accordance with some aspects of various example embodiments of the present disclosure. [Figure 4C] 1 illustrates an example mapping between transport channels and physical channels in a sidelink in accordance with some aspects of various example embodiments of the present disclosure. [Figure 5A] 1 illustrates an example radio protocol stack for NR sidelink communications in accordance with some aspects of various exemplary embodiments of the present disclosure. [Figure 5B] 1 illustrates an example radio protocol stack for NR sidelink communications in accordance with some aspects of various exemplary embodiments of the present disclosure. [Figure 5C] 1 illustrates an example radio protocol stack for NR sidelink communications in accordance with some aspects of various exemplary embodiments of the present disclosure. [Figure 5D] 1 illustrates an example radio protocol stack for NR sidelink communications in accordance with some aspects of various exemplary embodiments of the present disclosure. [Figure 6] 1 illustrates exemplary physical signals in the downlink, uplink, and sidelink in accordance with some aspects of some of the various exemplary embodiments of the present disclosure. [Figure 7] 1 illustrates examples of Radio Resource Control (RRC) states and transitions between different RRC states, in accordance with some aspects of various exemplary embodiments of the present disclosure. [Figure 8] 1 illustrates an example frame structure and physical resources in accordance with some aspects of various example embodiments of the present disclosure. [Figure 9] 1 illustrates example component carrier configurations in different carrier aggregation scenarios in accordance with some aspects of various example embodiments of the present disclosure. [Figure 10] 1 illustrates exemplary bandwidth portion configurations and switching in accordance with some aspects of various exemplary embodiments of the present disclosure. [Figure 11] 1 illustrates an example of a four-step contention-based and contention-free random access process in accordance with some aspects of various exemplary embodiments of the present disclosure. [Figure 12] 1 illustrates an example of a two-step contention-based and contention-free random access process in accordance with some aspects of various exemplary embodiments of the present disclosure. [Figure 13]1 illustrates an example time and frequency structure of synchronization signals and Physical Broadcast Channel (PBCH) blocks (SSBs) in accordance with some aspects of various example embodiments of the present disclosure. [Figure 14] 1 illustrates an exemplary SSB burst transmission in accordance with some aspects of various exemplary embodiments of the present disclosure. [Figure 15] 1 illustrates example components of a user equipment and a base station for transmission and / or reception in accordance with some aspects of various example embodiments of the present disclosure. [Figure 16] 1 illustrates an example process according to some aspects of some of various example embodiments of the present disclosure. [Figure 17] 1 illustrates an example process according to some aspects of some of various example embodiments of the present disclosure. [Figure 18] 1 illustrates an example process according to some aspects of some of various example embodiments of the present disclosure. [Figure 19] 1 illustrates an example process according to some aspects of some of various example embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0015] 1 illustrates an example of a mobile communication system 100 according to some aspects of some of the various exemplary embodiments of the present disclosure. The mobile communication system 100 may be operated by a wireless communication system operator, such as a Mobile Network Operator (MNO), a private network operator, a Multiple System Operator (MSO), an Internet of Things (IOT) network operator, etc., and may provide services such as voice, data (e.g., wireless Internet access), messaging, vehicular communication services such as Vehicle to Everything (V2X) communication services, safety services, mission-critical services, and services in residential, commercial, or industrial environments, such as IoT and industrial IOT (IIOT).

[0016] The mobile communication system 100 can enable various types of applications with different requirements in terms of delay, reliability, throughput, etc. Examples of supported applications include enhanced Mobile Broadband (eMBB), Ultra-Reliable Low-Latency Communications (URLLC), and massive Machine Type Communications (mMTC). eMBB can support stable connections at high peak data rates as well as stable connections at moderate rates for cell edge users. URLLC can support applications with stringent requirements in terms of delay and reliability as well as applications with moderate requirements in terms of data rate. An example of an mMTC application is a network of a huge number of IoT devices that are only sporadically active and transmit small data payloads.

[0017] The mobile communication system 100 may include a radio access network (RAN) portion and a core network portion. The example shown in FIG. 1 illustrates a Next Generation RAN (NG-RAN) 105 and a 5G Core Network (5GC) 110 as examples of the RAN and the core network, respectively. Other examples of the RAN and the core network may be implemented without departing from the scope of this disclosure. Other examples of the RAN include an Evolved Universal Terrestrial Radio Access Network (EUTRAN), a Universal Terrestrial Radio Access Network (UTRAN), etc. Other examples of the core network include an Evolved Packet Core (EPC), a UMTS Core Network (UCN), etc. The RAN implements a radio access technology (RAT) and resides between a user equipment (UE) 125 and the core network. Examples of such RATs include New Radio (NR), Long Term Evolution (LTE), also known as Evolved Universal Terrestrial Radio Access (EUTRA), and Universal Mobile Telecommunication System (UMTS). The RAT of the exemplary mobile communication system 100 may be NR. The core network exists between the RAN and one or more external networks (e.g., data networks, etc.) and is responsible for functions such as mobility management, authentication, session management, bearer setup, and application of various Quality of Services (QoS). The functional layer between the UE 125 and the RAN (e.g., the NG-RAN 105) may be referred to as the Access Stratum (AS), and the functional layer between the UE 125 and the core network (e.g., the 5GC 110) may be referred to as the Non-access Stratum (NAS).

[0018] The UE 125 may include wireless transmission and reception means for communicating with one or more nodes in a RAN, one or more relay nodes, one or more other UEs, etc. Examples of a UE include, but are not limited to, a smartphone, a tablet, a laptop, a computer, a wireless transmitting and / or receiving unit in a vehicle, a V2X or vehicle-to-vehicle (V2V) device, a wireless sensor, an IoT device, an IIOT device, etc. Other names may be used for a UE, such as a mobile station (MS), terminal equipment, terminal node, client device, mobile device, etc.

[0019] The RAN may include nodes (e.g., base stations) for communication with UEs. For example, the NG-RAN 105 of the mobile communication system 100 may include nodes for communication with the UE 125. Different names may be used for the RAN nodes depending, for example, on the RAT used for the RAN. A RAN node may be referred to as a Node B (NB) in a RAN using the UMTS RAT. A RAN node may be referred to as an Evolved Node B (eNB) in a RAN using the LTE / EUTRA RAT. With respect to the illustrative example of the mobile communication system 100 of FIG. 1 , a node of the NG-RAN 105 may be either a Next Generation Node B (gNB) 115 or a Next Generation Evolved Node B (ng-eNB) 120. In this specification, the terms base station, RAN node, gNB, and ng-eNB may be used interchangeably. The gNB 115 may provide NR user plane protocol termination and control plane protocol termination toward the UE 125. The ng-eNB 120 may provide E-UTRA user plane protocol termination and control plane protocol termination toward the UE 125. The interface between the gNB 115 and the UE 125, or between the ng-eNB 120 and the UE 125, may be referred to as a Uu interface. The Uu interface may be established using a user plane protocol stack and a control plane protocol stack. For the Uu interface, the direction from the base station (e.g., the gNB 115 or the ng-eNB 120) to the UE 125 may be referred to as the downlink, and the direction from the UE 125 to the base station (e.g., the gNB 115 or the ng-eNB 120) may be referred to as the uplink.

[0020] The gNB 115 and the ng-eNB 120 may be interconnected by an Xn interface. The Xn interface may include an Xn user plane (Xn-U) interface and an Xn control plane (Xn-C) interface. The transport network layer of the Xn-U interface is built on Internet Protocol (IP) transport, and the GPRS Tunneling Protocol (GTP) may be used on top of User Datagram Protocol (UDP) / IP to transport user plane protocol data units (PDUs). Xn-U provides non-guaranteed delivery of user plane PDUs and can support data forwarding and flow control. The transport network layer of the Xn-C interface may be built on the Stream Control Transport Protocol (SCTP) on top of IP. The application layer signaling protocol may be referred to as Xn Application Protocol (XnAP). The SCTP layer can guarantee delivery of application layer messages. The transport IP layer can deliver signaling PDUs using point-to-point transmission. The Xn-C interface can support Xn interface management, UE mobility management including context transfer and RAN paging, and dual connectivity.

[0021] The gNB 115 and the ng-eNB 120 may also be connected to the 5GC 110 via an NG interface, more specifically, to the Access and Mobility Management Function (AMF) 130 of the 5GC 110 via an NG-C interface and to the User Plane Function (UPF) 135 of the 5GC 110 via an NG-U interface. The transport network layer of the NG-U interface may be built on IP transport, and the GTP protocol may be used on top of UDP / IP to carry user plane PDUs between the NG-RAN node (e.g., the gNB 115 or the ng-eNB 120) and the UPF 135. The NG-U may provide non-guaranteed delivery of user plane PDUs between the NG-RAN node and the UPF. The transport network layer of the NG-C interface may be built on IP transport. SCTP may be added on top of IP to reliably transport signaling messages. The application layer signaling protocol may be referred to as the NG Application Protocol (NGAP). The SCTP layer can guarantee delivery of application layer messages. For transport, signaling PDUs can be delivered using point-to-point transmission at the IP layer. The NG-C interface can provide the following functions: NG interface management, UE context management, UE mobility management, transport of NAS messages, paging, PDU session management, transfer of configuration, and sending of alert messages.

[0022] The gNB115 or ng-eNB120 may host one or more of the following functions: Radio resource management functions such as radio bearer control, radio admission control, connection mobility control, dynamic allocation of resources to UEs in both uplink and downlink (e.g., scheduling); IP and Ethernet header compression, encryption, and data integrity protection; AMF selection at UE attachment time if routing to the AMF cannot be determined from information provided by the UE; routing of user plane data to UPF(s); routing of control plane information to the AMF; connection setup and release; scheduling and transmission of paging messages; scheduling and transmission of system broadcast information (e.g., originated from the AMF); measurement and measurement reporting configuration for mobility and scheduling; marking of transport-level packets in the uplink; session management; support for network slicing; QoS flow management and mapping to data radio bearers; support for UEs in RRC inactive state; distribution functions for NAS messages; radio access network sharing; dual connectivity; close interaction between NR and E-UTRA; and maintenance of security and radio settings for user plane 5G System (5GS) Cellular IoT (CIoT) optimization.

[0023] The AMF 130 may host one or more of the following functions: NAS signaling termination; NAS signaling security; AS security control; CN inter-node signaling for mobility between 3GPP access networks; idle mode UE reachability (including control and execution of paging retransmissions); registration area management; support for intra-system and inter-system mobility; access authentication; access authentication including checking roaming rights; mobility management control (subscription and policy); support for network slicing; Session Management Function (SMF) selection; and 5GS CIoT optimization selection.

[0024] The UPF 135 can host one or more of the following functions: anchor point for intra / inter-RAT mobility (if applicable); external PDU session point for interconnection to data networks; packet routing and forwarding; packet inspection and user plane part of policy rule enforcement; traffic usage reporting; uplink classifier to support routing of traffic flows to data networks; branching point to support multi-homed PDU sessions; user plane QoS processing, e.g., packet filtering, gating, UL / DL rate enforcement; uplink traffic validation (Service Data Flow (SDF) to QoS flow mapping); downlink packet buffering and downlink data notification triggering.

[0025] As shown in FIG. 1 , the NG-RAN 105 can support a PC5 interface between two UEs 125 (e.g., between UE 125A and UE 125B). In the PC5 interface, the direction of communication between two UEs (e.g., from UE 125A to UE 125B or vice versa) may be referred to as a sidelink. Sidelink transmission and reception over the PC5 interface can be supported when the UE 125 is within the coverage of the NG-RAN 105 and when the UE 125 is out of the coverage of the NG-RAN 105, regardless of the RRC state the UE is in. Support for V2X services over the PC5 interface can be provided by NR sidelink communication and / or V2X sidelink communication.

[0026] PC5-S signaling can be used to establish a unicast link via a direct communication request / accept message. A UE can self-assign the source layer-2 ID of a PC5 unicast link, for example, based on the V2X service type. During the unicast link establishment procedure, a UE can send the source layer-2 ID of a PC5 unicast link to a peer UE, for example, a UE from which the destination ID was received from a higher layer. The pair of source layer-2 ID and destination layer-2 ID can uniquely identify a unicast link. The receiving UE can verify that the destination ID is its own and accept the unicast link establishment request from the source UE. During the PC5 unicast link establishment procedure, a PC5-RRC procedure on the access stratum can be invoked for purposes such as UE sidelink context establishment, AS layer configuration, and capability exchange. PC5-RRC signaling can exchange UE capabilities and AS layer configuration, such as sidelink radio bearer configuration, between a pair of UEs between which a PC5 unicast link is established.

[0027] NR sidelink communication can support one of three transmission modes (e.g., unicast transmission, groupcast transmission, and broadcast transmission) for a pair of source and destination Layer-2 IDs in an AS. The unicast transmission mode can be characterized by supporting one PC5-RRC connection between peer UEs for the pair; transmitting and receiving control information and user traffic between peer UEs on the sidelink; supporting sidelink HARQ feedback; supporting sidelink transmit power control; supporting RLC Acknowledged Mode (AM); and detecting radio link failures of the PC5-RRC connection. The groupcast transmission can be characterized by transmitting and receiving user traffic between UEs belonging to a group on the sidelink; and supporting sidelink HARQ feedback. The broadcast transmission can be characterized by transmitting and receiving user traffic between UEs on the sidelink.

[0028] The source Layer-2 ID, destination Layer-2 ID, and PC5 link identifier may be used in NR sidelink communications. The source Layer-2 ID may be a link layer identity that identifies the device or group of devices that is the recipient of the sidelink communication frame. The destination Layer-2 ID may be a link layer identity that identifies the device that originates the sidelink communication frame. In some examples, the source Layer-2 ID and destination Layer-2 ID may be assigned by a management function in the core network. The source Layer-2 ID may identify the sender of data in NR sidelink communications. The source Layer-2 ID may be 24 bits long and may be split into two bit strings at the MAC layer. One bit string may be the least significant bit (8 bits) of the source Layer-2 ID and may be forwarded to the sender's physical layer. This may identify the source of the desired data in the sidelink control information and may be used for packet filtering at the receiver's physical layer. The second bit string may be the MSB portion (16 bits) of the source Layer-2 ID and may be carried within the Medium Access Control (MAC) header. This can be used for packet filtering at the receiver's MAC layer. The destination Layer-2 ID can identify the target of the data in NR sidelink communication. For NR sidelink communication, the destination Layer-2 ID may be 24 bits long and may be split into two bit strings at the MAC layer. One bit string is the LSB portion (16 bits) of the destination Layer-2 ID and may be forwarded to the sender's physical layer. This can identify the target of the desired data in the sidelink control information and can be used for packet filtering at the receiver's physical layer. The second bit string may be the MSB portion (8 bits) of the destination Layer-2 ID and may be carried within the MAC header. This can be used for packet filtering at the receiver's MAC layer. The PC5 link identifier can uniquely identify a PC5 unicast link within the UE for the lifetime of the PC5 unicast link.The PC5 link identifier may be used to indicate the PC5 unicast link on which a sidelink Radio Link failure (RLF) declaration has been made and the PC5-RRC connection has been released.

[0029] 2A and 2B illustrate example user and control plane radio protocol stacks, respectively, in accordance with some aspects of some of the various example embodiments of the present disclosure. As shown in FIG. 2A, the user plane protocol stack of the Uu interface (between the UE 125 and the gNB 115) includes Service Data Adaptation Protocol (SDAP) 201 and SDAP 211, Packet Data Convergence Protocol (PDCP) 202 and PDCP 212, Radio Link Control (RLC) 203 and RLC 213, MAC 204 and MAC 214 sublayers of Layer 2, and Physical (PHY) Layer 205 and PHY 215 layers (Layer 1, also referred to as L1).

[0030] The PHY205 and PHY215 provide transport channels 244 to the MAC204 and MAC214 sublayers. The MAC204 and MAC214 sublayers provide logical channels 243 to the RLC203 and RLC213 sublayers. The RLC203 and RLC213 sublayers provide RLC channels 242 to the PDCP202 and PCP212 sublayers. The PDCP202 and PDCP212 sublayers provide radio bearers 241 to the SDAP201 and SDAP211 sublayers. Radio bearers can be categorized into two groups: data radio bearers (DRBs) for user plane data and signaling radio bearers (SL SRBs) for control plane data. The SDAP201 and SDAP211 sublayers provide QoS flows 240 to the 5GC.

[0031] The main services and functions of the MAC204 or MAC214 sublayer include mapping between logical channels and transport channels; multiplexing / demultiplexing of MAC Service Data Units (SDUs) belonging to one or different logical channels into / from Transport Blocks (TBs) delivered to / from the physical layer on transport channels; scheduling of information reports; error correction with Hybrid Automatic Repeat Request (HARQ) (one HARQ entity per cell in case of carrier aggregation (CA)); prioritization between UEs with dynamic scheduling; prioritization between logical channels of one UE with Logical Channel Prioritization (LCP); prioritization between overlapping resources of one UE; and padding. A single MAC entity can support multiple numerologies, transmission timings, and cells. Mapping restrictions in the logical channel prioritization control which numerology(s), cell(s), and transmission timing(s) a logical channel can use.

[0032] The HARQ function can guarantee delivery between peer entities at Layer 1. If the physical layer is not configured for downlink / uplink spatial multiplexing, a single HARQ process can support one TB, and if the physical layer is configured for downlink / uplink spatial multiplexing, a single HARQ process can support one or more TBs.

[0033] The RLC203 or RLC213 sublayer can support three transmission modes: Transparent Mode (TM); Unacknowledged Mode (UM); and Acknowledged Mode (AM). The RLC configuration can be per logical channel independent of numerology and / or transmission period, and Automatic Repeat Request (ARQ) can operate with either the numerology and / or transmission period for which the logical channel is configured.

[0034] The main services and functions of the RLC203 or RLC213 sublayer depend on the transmission mode (e.g., TM, UM, or AM) and may include: transfer of upper layer PDUs; sequence numbering independent of the numbering in PDCP (UM and AM); error correction via ARQ (AM only); RLC SDU segmentation (AM and UM) and resegmentation (AM only); SDU reassembly (AM and UM); duplicate detection (AM only); RLC SDU discard (AM and UM); RLC re-establishment; and protocol error detection (AM only).

[0035] An automatic repeat request in the RLC203 or RLC213 sublayer may have the following characteristics: ARQ retransmits an RLC SDU or an RLC SDU segment based on an RLC status report; polling of the RLC status report can be used if required by the RLC; the RLC receiver can also trigger an RLC status report after detecting a missing RLC SDU or an RLC SDU segment.

[0036] The main services and functions of the PDCP202 or PDCP212 sublayer may include forwarding of data (user plane or control plane); maintenance of PDCP Sequence Number (SN); header compression and decompression using the Robust Header Compression (ROHC) protocol; header compression and decompression using the EHC protocol; encryption and decryption; integrity protection and integrity verification; timer-based SDU discarding; routing for split bearers; duplication; reordering and in-order delivery; out-of-order delivery; and duplicate discarding.

[0037] The main services and functions of the SDAP 201 or SDAP 211 include mapping between QoS flows and data radio bearers, and marking QoS Flow IDs (QFIs) in both downlink and uplink packets. A single protocol entity of the SDAP can be configured for each individual PDU session.

[0038] As shown in FIG. 2B, the control plane protocol stack of the Uu interface (between UE 125 and gNB 115) includes the PHY layer (Layer 1), the MAC sublayer, RLC sublayer, and PDCP sublayer of Layer 2, as described above, and additionally includes the RRC206 sublayer and the RRC216 sublayer. The main services and functions of the RRC206 and RRC216 sublayers on the Uu interface include: broadcasting of system information related to AS and NAS; paging initiated by 5GC or NG-RAN; establishment, maintenance, and release of RRC connections between the UE and NG-RAN (including adding, modifying, and releasing carrier aggregation, and adding, modifying, and releasing dual connectivity within NR or between E-UTRA and NR); security functions including key management; establishment, configuration, maintenance, and release of SRBs and DRBs; mobility functions (including handover and context transfer, UE cell selection and reselection, cell selection and reselection control, and inter-RAT mobility); QoS management functions; UE measurement reporting and reporting control; radio link failure detection and recovery; and message forwarding from the UE to the NAS / NAS to the UE. The NAS207 and NAS227 layers are control protocols (terminated in the AMF on the network side) that perform functions such as authentication, mobility management, and security control.

[0039] Sidelink specific services and functions of the RRC sublayer over the Uu interface include configuration of sidelink resource allocation via system information or dedicated signaling, reporting of UE sidelink information, sidelink related measurement configuration and reporting, and reporting of UE assistance information regarding SL traffic pattern(s).

[0040] 3A, 3B, and 3C illustrate example mappings between logical channels and transport channels in the downlink, uplink, and sidelink, respectively, according to some aspects of some of the various example embodiments of the present disclosure. Different types of data transfer services may be provided by the MAC. Each logical channel type may be defined according to the type of information transferred. The logical channels may be classified into two groups: control channels and traffic channels. The control channels may be used only for the transfer of control plane information. The Broadcast Control Channel (BCCH) is a downlink channel for broadcasting system control information. The Paging Control Channel (PCCH) is a downlink channel for carrying paging messages. The Common Control Channel (CCCH) is a channel for transmitting control information between a UE and a network. This channel may be used for UEs that do not have an RRC connection with the network. The Dedicated Control Channel (DCCH) is a point-to-point bidirectional channel that transmits dedicated control information between a UE and a network and may be used by UEs that have an RRC connection. The traffic channels may be used only for the transfer of user plane information. A dedicated traffic channel (DTCH) is a point-to-point channel dedicated to one UE for transferring user information. DTCH can exist in both the uplink and downlink. A sidelink control channel (SCCH) is a sidelink channel for transmitting control information (e.g., PC5-RRC and PC5-S messages) from one UE to other UE(s). A sidelink traffic channel (STCH) is a sidelink channel for transmitting user information from one UE to other UE(s). A sidelink broadcast control channel (SBCCH) is a sidelink channel for broadcasting sidelink system information from one UE to other UE(s).

[0041] Downlink transport channel types include the Broadcast Channel (BCH), the Downlink Shared Channel (DL-SCH), and the Paging Channel (PCH). The BCH may be characterized by a fixed, predefined transport format and a requirement to be broadcast throughout the coverage area of ​​a cell, either as a single message or by beamforming of different BCH instances. The DL-SCH may be characterized by support for HARQ, support for dynamic link adaptation by changing modulation, coding, and transmit power, the possibility of being broadcast throughout the cell, the possibility of using beamforming, support for both dynamic and semi-static resource allocation, and support for UE discontinuous reception (DRX) to enable UE power savings. The DL-SCH may be characterized by support for HARQ, support for dynamic link adaptation by changing modulation, coding, and transmit power, the possibility of being broadcast throughout the cell, the possibility of using beamforming, support for both dynamic and semi-static resource allocation, and support for UE discontinuous reception (DRX) to enable UE power savings. The PCH may be characterized by support for UE discontinuous reception (DRX) to enable UE power saving (DRX cycle indicated to the UE by the network), the requirement to be broadcast throughout the coverage area of ​​the cell either as a single message or by beamforming of different PCH instances, and being mapped to physical resources that can also be dynamically used for traffic / other control channels.

[0042] In the downlink, between the logical channels and the transport channels, there may be a BCCH which may be mapped to a BCH, a BCCH which may be mapped to a DL-SCH, a PCCH which may be mapped to a PCH, a CCCH which may be mapped to a DL-SCH, a DCCH which may be mapped to a DL-SCH, and a DTCH which may be mapped to a DL-SCH.

[0043] Types of uplink transport channels include the Uplink Shared Channel (UL-SCH) and Random Access Channel(s) (RACH). The UL-SCH may be characterized by the possibility of using beamforming, support for dynamic link adaptation by changing transmit power and possibly modulation and coding, support for HARQ, and support for both dynamic and semi-static resource allocation. The RACH may be characterized by limited control information and risk of collisions.

[0044] In the uplink, there may be connections between logical channels and transport channels: CCCH, which may be mapped to UL-SCH; DCCH, which may be mapped to UL-SCH; and DTCH, which may be mapped to UL-SCH.

[0045] Types of sidelink transport channels include a sidelink broadcast channel (SL-BCH) and a sidelink shared channel (SL-SCH). The SL-BCH may feature a predefined transport format. The SL-SCH may feature support for unicast, groupcast, and broadcast transmissions, support for both UE autonomous resource selection and scheduled resource allocation by the NG-RAN, support for both dynamic and semi-static resource allocation when the UE is assigned resources by the NG-RAN, support for HARQ, and support for dynamic link adaptation by changing transmit power, modulation, and coding.

[0046] In the sidelink, there may be connections between logical channels and transport channels: SCCH, which may be mapped to SL-SCH, STCH, which may be mapped to SL-SCH, and SBCCH, which may be mapped to SL-BCH.

[0047] 4A, 4B, and 4C illustrate example mappings between transport channels and physical channels in the downlink, uplink, and sidelink, respectively, in accordance with some aspects of some of various example embodiments of the present disclosure. Downlink physical channels include a Physical Downlink Shared Channel (PDSCH), a Physical Downlink Control Channel (PDCCH), and a Physical Broadcast Channel (PBCH). The PCH and DL-SCH transport channels are mapped to the PDSCH. The BCH transport channel is mapped to the PBCH. While no transport channels are mapped to the PDCCH, downlink control information (DCI) is transmitted via the PDCCH.

[0048] Physical channels in the uplink include the Physical Uplink Shared Channel (PUSCH), the Physical Uplink Control Channel (PUCCH), and the Physical Random Access Channel (PRACH). The UL-SCH transport channel may be mapped to the PUSCH, and the RACH transport channel may be mapped to the PRACH. No transport channel is mapped to the PUCCH, but uplink control information (UCI) is transmitted via the PUCCH.

[0049] Physical channels in the sidelink include the Physical Sidelink Shared Channel (PSSCH), the Physical Sidelink Control Channel (PSCCH), the Physical Sidelink Feedback Channel (PSFCH), and the Physical Sidelink Broadcast Channel (PSBCH). The Physical Sidelink Control Channel (PSCCH) may indicate the resources and other transmission parameters used by the UE for the PSSCH. The Physical Sidelink Shared Channel (PSSCH) may transmit the data TB itself and control information such as HARQ procedures and CSI feedback triggers. At least six OFDM symbols in a slot may be used for PSSCH transmission. The Physical Sidelink Feedback Channel (PSFCH) may carry HARQ feedback over the sidelink from the UE that is the intended recipient of the PSSCH transmission to the UE that performed the transmission. The PSFCH sequence may be transmitted within one PRB repeated across two OFDM symbols near the end of the sidelink resources in a slot. The SL-SCH transport channel may be mapped to the PSSCH. The SL-BCH may be mapped to the PSBCH. Transport channels are not mapped to the PSFCH, but sidelink feedback control information (SFCI) may be mapped to the PSFCH. Transport channels are not mapped to the PSCCH, but sidelink control information (SCI) may be mapped to the PSCCH.

[0050] 5A, 5B, 5C, and 5D illustrate example radio protocol stacks for NR sidelink communications in accordance with some aspects of various exemplary embodiments of the present disclosure. The AS protocol stack for the user plane (i.e., for the STCH) of the PC5 interface may consist of the SDAP, PDCP, RLC, MAC sublayers, and a physical layer. The user plane protocol stack is shown in FIG. 5A. The AS protocol stack for the SBCCH in the PC5 interface may consist of the RRC, RLC, MAC sublayers, and a physical layer, as shown in FIG. 5B below. To support the PC5-S protocol, PC5-S sits on top of the PDCP, RLC, and MAC sublayers and the physical layer in the control plane protocol stack for the SCCH for PC5-S, as shown in FIG. 5C. The AS protocol stack for the control plane of the SCCH for RRC in the PC5 interface consists of the RRC, PDCP, RLC, and MAC sublayers, and a physical layer. The control plane protocol stack for the SCCH for RRC is shown in FIG. 5D.

[0051] Sidelink Radio Bearers (SLRBs) can be classified into two groups: Sidelink Data Radio Bearers (SL DRBs) for user plane data and Sidelink Signaling Radio Bearers (SL SRBs) for control plane data. Separate SL SRBs using different SCCHs can be configured for PC5-RRC signaling and PC5-S signaling, respectively.

[0052] The MAC sublayer may provide the following services and functions over the PC5 interface: radio resource selection, packet filtering, prioritization between uplink and sidelink transmissions for a given UE, and sidelink CSI reporting. Due to MAC logical channel priority restrictions, only sidelink logical channels belonging to the same destination may be multiplexed into the MAC PDU for all unicast, groupcast, and broadcast transmissions that may be associated with the destination. For packet filtering, an SL-SCH MAC header containing both the source Layer-2 ID and the destination Layer-2 ID portion may be added to the MAC PDU. The logical channel identifier (LCID) contained within the MAC subheader may uniquely identify a logical channel within the combination of the source Layer-2 ID and the destination Layer-2 ID.

[0053] The services and functions of the RLC sublayer may be supported for the sidelink. Both RLC unacknowledged mode (UM) and acknowledged mode (AM) may be used in unicast transmission, but only UM may be used in groupcast or broadcast transmission. For UM, only one-way transmission may be supported in groupcast and broadcast.

[0054] The services and functions of the PDCP sublayer for the Uu interface may be supported for the sidelink with some restrictions: out-of-order delivery may only be supported for unicast transmissions, and duplication may not be supported across the PC5 interface.

[0055] The SDAP sublayer may provide the following services and functions over the PC5 interface: Mapping between QoS flows and sidelink data radio bearers There may be one SDAP entity per destination for one of unicast, groupcast and broadcast associated with the destination.

[0056] The RRC sublayer may provide the following services and functions across the PC5 interface: forwarding PC5-RRC messages between peer UEs, maintaining and releasing a PC5-RRC connection between two UEs, and detecting sidelink radio link failures of a PC5-RRC connection based on indications from MAC or RLC. A PC5-RRC connection may be a logical connection between two UEs for a pair of source and destination Layer-2 IDs that is considered established after a corresponding PC5 unicast link is established. There may be a one-to-one correspondence between PC5-RRC connections and PC5 unicast links. A UE may have multiple PC5-RRC connections with one or more UEs for different pairs of source and destination Layer-2 IDs. Separate PC5-RRC procedures and messages may be used by a UE to transfer sidelink configuration, including UE capabilities and SL-DRB configuration, to a peer UE. Both peer UEs may exchange their UE capabilities and sidelink configuration using separate bidirectional procedures in both directions of the sidelink.

[0057] FIG. 6 illustrates example physical signals in the downlink, uplink, and sidelink according to some aspects of various exemplary embodiments of the present disclosure. Demodulation reference signals (DM-RSs) may be used in the downlink, uplink, and sidelink and may be used for channel estimation. DM-RSs are UE-specific reference signals that may be transmitted together with physical channels in the downlink, uplink, or sidelink and may be used for channel estimation and coherent detection of the physical channels. Phase tracking reference signals (PT-RSs) may be used in the downlink, uplink, and sidelink and may be used to track phase and mitigate performance loss due to phase noise. PT-RSs may be primarily used to estimate and minimize the impact of common phase error (CPE) on system performance. Due to phase noise characteristics, PT-RS signals may be sparse in the frequency domain and dense in the time domain. PT-RSs may occur in combination with DM-RSs if the network is configured to have PT-RSs present. A positioning reference signal (PRS) may be used in the downlink for positioning using various positioning techniques. The PRS may be used to measure the delay of downlink transmissions by correlating the received signal from the base station with a local replica in the receiver. A channel state information reference signal (CSI-RS) may be used in the downlink and sidelink. The CSI-RS may be used for channel state estimation, reference signal received power (RSRP) measurement for mobility and beam management, time / frequency tracking for demodulation, etc. Although the CSI-RS may be UE-specific, multiple users may share the same CSI-RS resource. The UE can determine a CSI report and transmit it in the uplink to the base station using the PUCCH or PUSCH. The CSI report may be carried in the sidelink MAC CE. A primary synchronization signal (PSS) and a secondary synchronization signal (SSS) may be used for radio frame synchronization. The PSS and SSS may be used for cell search procedures during initial connection or for mobility purposes. A sounding reference signal (SRS) may be used in the uplink for uplink channel estimation.Similar to the CSI-RS, the SRS can serve as a QCL reference for other physical channels so that they can be configured and transmitted quasi-co-located with the SRS. Sidelink PSS (S-PSS) and Sidelink SSS (S-SSS) can be used in the sidelink for sidelink synchronization.

[0058] 7 illustrates examples of radio resource control (RRC) states and transitions between different RRC states in accordance with some aspects of some of the various exemplary embodiments of the present disclosure. A UE may be in one of three RRC states: an RRC connected state 710, an RRC idle state 720, and an RRC inactive state 730. After power-on, the UE may be in the RRC idle state 720, and the UE may establish a connection with the network via an RRC connection establishment procedure using initial access to perform data transfer and / or make / receive voice calls. Once an RRC connection is established, the UE may be in the RRC connected state 710. The UE may transition from the RRC idle state 720 to the RRC connected state 710 or from the RRC connected state 710 to the RRC idle state 720 using an RRC connection establishment / release procedure 740.

[0059] The RRC inactive state 730 may be used to reduce the signaling load and delay caused by frequent transitions from the RRC connected state 710 to the RRC idle state 720 when the UE frequently transmits small data. In the RRC inactive state 730, the AS context may be stored by both the UE and the gNB. This may allow for a faster state transition from the RRC inactive state 730 to the RRC connected state 710. The UE may transition from the RRC inactive state 730 to the RRC connected state 710 or from the RRC connected state 710 to the RRC inactive state 730 using an RRC connection resume / deactivation procedure 760. The UE may transition from the RRC inactive state 730 to the RRC idle state 720 using an RRC disconnection procedure 750.

[0060] FIG. 8 illustrates an example frame structure and physical resources according to some aspects of some of the various exemplary embodiments of the present disclosure. Downlink, uplink, or sidelink transmissions may be organized into frames of 10 ms duration consisting of ten 1 ms subframes. Each subframe may consist of 1, 2, 4, ... slots, and the number of slots per subframe may depend on the subcarrier spacing of the carrier on which the transmission occurs. The slot duration is 14 symbols with a normal cyclic prefix (CP) or 12 symbols with an extended CP, and may be scaled in time as a function of the subcarrier spacing used so that there are an integer number of slots in a subframe. FIG. 8 illustrates a resource grid in the time and frequency domains. Each element of the resource grid, which comprises one symbol in time and one subcarrier in frequency, is referred to as a resource element (RE). A resource block (RB) may be defined as 12 consecutive subcarriers in the frequency domain.

[0061] In some examples, in non-slot-based scheduling, the transmission of a packet may occur over a portion of a slot, e.g., 2, 4, or 7 OFDM symbols, which may also be referred to as a minislot. Minislots may be used for low-latency applications such as URLLC and operation in unlicensed bands. In some embodiments, minislots may also be used for fast and flexible scheduling of services (e.g., preemption for URLLC over eMBB).

[0062] FIG. 9 illustrates example component carrier configurations in different carrier aggregation scenarios according to some aspects of various example embodiments of the present disclosure. In carrier aggregation (CA), two or more component carriers (CCs) may be aggregated. A UE may simultaneously receive or transmit on one or more CCs depending on the UE's capabilities. CA may be supported for both contiguous and non-contiguous CCs within the same band or on different bands, as shown in FIG. 9. The gNB and UE may communicate using a serving cell. The serving cell may be associated with at least one downlink CC (e.g., may be associated with only one downlink CC or may be associated with a downlink CC and an uplink CC). The serving cell may be a primary cell (PCell) or a secondary cCell (SCell).

[0063] The UE may adjust the timing of its uplink transmission using an uplink timing control procedure. It may use a timing advance (TA) to adjust the uplink frame timing relative to the downlink frame timing. The gNB may determine a desired timing advance setting and provide it to the UE. The UE may use the provided TA to determine the uplink transmission timing relative to the downlink reception timing observed by the UE.

[0064] In the RCC connected state, the gNB may be responsible for maintaining the timing advance to maintain L1 synchronization. Serving cells with uplinks to which the same timing advance is applied and that use the same timing reference cell are grouped into a timing advance group (TAG). A TAG may contain at least one serving cell with a configured uplink. The mapping of serving cells to TAGs may be configured by RRC. For the primary TAG, the UE may also use the PCell as the timing reference cell, except for shared spectrum channel access, where an SCell is also used as a timing reference cell in certain cases. For a secondary TAG, the UE may use any of the activated SCells of this TAG as the timing reference cell and may not change it unless necessary.

[0065] The timing advance update may be signaled by the gNB to the UE via a MAC CE command. Such a command may restart a TAG-specific timer that may indicate whether L1 can be synchronized; if the timer is running, L1 may be considered synchronized; otherwise, L1 may be considered unsynchronized (in which case uplink transmissions may only occur on the PRACH).

[0066] A UE with a single timing advance capability for CA may simultaneously receive and / or transmit on multiple CCs corresponding to multiple serving cells (multiple serving cells grouped into one TAG) sharing the same timing advance. A UE with multiple timing advance capabilities for CA may simultaneously receive and / or transmit on multiple CCs corresponding to multiple serving cells (multiple serving cells grouped into multiple TAGs) with different timing advances. The NG-RAN may ensure that each TAG contains at least one serving cell. A non-CA-capable UE may receive on a single CC and transmit on a single CC corresponding to only one serving cell (one serving cell in one TAG).

[0067] The multi-carrier nature of the physical layer in the case of CA may be exposed to the MAC layer, and one HARQ entity may be required per serving cell. When CA is configured, the UE may have one RRC connection with the network. At RRC connection establishment / re-establishment / handover, one serving cell (e.g., PCell) may provide NAS mobility information. Depending on the UE capabilities, an SCell may be configured to form a set of serving cells together with the PCell. The set of serving cells configured for a UE may consist of one PCell and one or more SCells. Reconfiguration, addition, and deletion of SCells may be performed by RRC.

[0068] In a dual connectivity scenario, a UE may be configured with multiple cells including a Master Cell Group (MCG) for communicating with a master base station, a Secondary Cell Group (SCG) for communicating with secondary base stations, and two MAC entities, one MAC entity for the MCG for communicating with the master base station and one MAC entity for the SCG for communicating with the secondary base stations.

[0069] FIG. 10 illustrates exemplary bandwidth portion configuration and switching according to some aspects of some of the various exemplary embodiments of the present disclosure. A UE may be configured with one or more bandwidth portions (BWPs) 1010 on a given component carrier. In some examples, one of the one or more bandwidth portions may be active at a time. The active bandwidth portion may define the UE's operating bandwidth within the cell's operating bandwidth. For initial access, an initial bandwidth portion 1020 determined from system information may be used until the UE's configuration within the cell is received. For example, through bandwidth adaptation (BA) via BWP switching 1040, the UE's transmit and receive bandwidth may not be as large as the cell's bandwidth and may be adjusted. For example, the width may be commanded to change (e.g., shrink during periods of low activity to save power), the location may be moved within the frequency domain (e.g., for increased scheduling flexibility), or the subcarrier spacing may be commanded to change (e.g., to allow different services). The first active BWP 1020 may be the active BWP upon RRC (re)configuration of the PCell or activation of the SCell.

[0070] For a downlink BWP or an uplink BWP in the set of downlink or uplink BWPs, the UE may be provided with the following configuration parameters, respectively: subcarrier spacing (SCS), cyclic prefix, common RB and number of consecutive RBs, index within the set of downlink or uplink BWPs by the respective BWP-Id, set of BWP common parameters and set of BWP-specific parameters. A BWP may be associated with an OFDM numerology according to the configured subcarrier spacing and cyclic prefix for the BWP. For the serving cell, the UE may be provided with a default downlink BWP among the configured downlink BWPs. If the UE is not provided with a default downlink BWP, the default downlink BWP may be the initial downlink BWP.

[0071] A downlink BWP may be associated with a BWP inactivity timer. If the BWP inactivity timer associated with an active downlink BWP expires and a default downlink BWP is configured, the UE may perform a BWP switch to the default BWP. If the BWP inactivity timer associated with an active downlink BWP expires and a default downlink BWP is not configured, the UE may perform a BWP switch to the initial downlink BWP.

[0072] 11 illustrates an example of a four-step contention-based and contention-free random access process according to some aspects of various exemplary embodiments of the present disclosure. Figure 12 illustrates an example of a two-step contention-based and contention-free random access process according to some aspects of various exemplary embodiments of the present disclosure. The random access procedure can be triggered by a number of events, such as initial access from an RRC idle state, an RRC connection re-establishment procedure, uplink synchronization status being "unsynchronized," downlink or uplink data arrival during an RRC connected state, no PUCCH resources available for a scheduling request (SR), uplink data arrival during an RRC connected state, a failure of an SR, a request by RRC upon synchronization reconfiguration (e.g., handover), a transition from an RRC inactive state, establishing time alignment for a secondary TAG, a request for other system information (SI), beam failure recovery (BFR), and a consistent uplink listen-before-talk (LBT) failure on the PCell.

[0073] Two types of random access (RA) procedures may be supported: a four-step RA type with MSG1 and a two-step RA type with MSGA. Both types of RA procedures may support contention-based random access (CBRA) and contention-free random access (CFRA), as shown in Figures 11 and 12.

[0074] The UE may select a random access type at the start of a random access procedure based on the network configuration. If a CFRA resource is not configured, the UE may use an RSRP threshold to select between a 2-step RA type and a 4-step RA type. If a CFRA resource with a 4-step RA type is configured, the UE may perform random access using the 4-step RA type. If a CFRA resource with a 2-step RA type is configured, the UE may perform random access using the 2-step RA type.

[0075] MSG1 for the 4-step RA type may consist of a preamble on the PRACH. After transmitting MSG1, the UE may monitor for a response from the network within a configured window. For CFRA, a dedicated preamble for MSG1 transmission may be assigned by the network, and upon receiving a random access response (RAR) from the network, the UE may terminate the random access procedure as shown in FIG. 11. For CBRA, upon receiving a random access response, the UE may transmit MSG3 using the uplink grant scheduled in the random access response and may monitor contention resolution as shown in FIG. 11. If contention resolution is not successful after MSG3 (re)transmission(s), the UE may return to MSG1 transmission.

[0076] The MSGA for the two-step RA type may include a preamble on the PRACH and a payload on the PUSCH. After the MSGA transmission, the UE may monitor a response from the network within a configured window. For CFRA, a dedicated preamble and PUSCH resources may be configured for MSGA transmission, and upon receiving a network response, the UE may terminate the random access procedure as shown in FIG. 12. For CBRA, if contention resolution is successful upon receiving a network response, the UE may terminate the random access procedure as shown in FIG. 12; on the other hand, if a fallback indicator is received in MSGB, the UE may perform MSG3 transmission using the uplink grant scheduled in the fallback indicator and monitor contention resolution. If contention resolution is not successful after MSG3 (re)transmission(s), the UE may return to MSGA transmission.

[0077] FIG. 13 illustrates an example of a time and frequency structure of a synchronization signal and physical broadcast channel (PBCH) block (SSB) according to some aspects of various exemplary embodiments of the present disclosure. The SS / PBCH block (SSB) may consist of a primary synchronization signal (PSS) and a secondary synchronization signal (SSS), each occupying one symbol and 127 subcarriers (e.g., subcarrier numbers 56-182 in FIG. 13). The PBCH spans three OFDM symbols and 240 subcarriers, with an unused portion for the SSS in the center of one symbol, as shown in FIG. 13. The possible time locations of the SSBs within a half-frame may be determined by the subcarrier spacing, and the periodicity of the half-frames in which the SSBs are transmitted may be configured by the network. During a half-frame, different SSBs may be transmitted in different spatial directions (i.e., using different beams to cover the cell's coverage area).

[0078] The PBCH may be used to carry a Master Information Block (MIB) used by the UE during cell search and initial access procedures. The UE may first decode the PBCH / MIB to receive other system information. The MIB may provide the UE with parameters necessary to acquire System Information Block 1 (SIB1), more specifically, information necessary to monitor the PDCCH for scheduling the PDSCH carrying SIB1. Additionally, the MIB may indicate cell barred status information. The MIB and SIB1 may collectively be referred to as Minimum System Information (SI), and SIB1 may be referred to as Remaining Minimum System Information (RMSI). Other System Information Blocks (SIBs) (e.g., SIB2, SIB3, ..., SIB10, and SIBpos) may be referred to as other SIs. Other SI may be broadcast periodically on the DL-SCH, may be broadcast on demand on the DL-SCH (e.g., upon request from a UE in RRC idle, RRC inactive, or RRC connected state), or may be sent in a dedicated manner on the DL-SCH to RRC connected UEs (e.g., if configured by the network, upon request from an RRC connected UE, or if the UE has an active BWP with no common search space configured).

[0079] FIG. 14 illustrates an exemplary SSB burst transmission according to some aspects of various exemplary embodiments of the present disclosure. An SSB burst may include N SSBs, where each SSB of the N SSBs may correspond to a beam. The SSB burst may be transmitted according to a period (e.g., an SSB burst period). During a contention-based random access process, the UE may perform a random access resource selection process, in which the UE first selects an SSB before selecting an RA preamble. The UE may select an SSB with an RSRP above a configured threshold. In some embodiments, if an SSB with an RSRP above a configured threshold is not available, the UE may select any SSB. The SSB may have a set of random access preambles associated with it. After selecting the SSB, the UE may select a random access preamble from the set of random access preambles associated with the SSB and transmit the selected random access preamble to initiate the random access process.

[0080] In some embodiments, any beam among the N beams may be associated with a CSI-RS resource. The UE may measure the CSI-RS resource and select a CSI-RS with an RSRP above a configured threshold. The UE may select a random access preamble corresponding to the selected CSI-RS and may transmit the selected random access process to initiate the random access process. If there is no random access preamble associated with the selected CSI-RS, the UE may select a random access preamble corresponding to an SSB quasi-colocated with the selected CSI-RS.

[0081] In some embodiments, based on the UE measurements of CSI-RS resources and the UE CSI report, the base station may determine a Transmission Configuration Indication (TCI) state and indicate the TCI state to the UE, where the UE may use the indicated TCI state for reception of downlink control information (e.g., via the PDCCH) or data (e.g., via the PDSCH). The UE may use the indicated TCI state to use an appropriate beam for reception of the data or control information. The indication of the TCI state may use an RRC configuration or a combination of RRC and dynamic signaling (e.g., via a MAC Control Element (MAC CE) and / or based on the value of a field in the downlink control information that schedules the downlink transmission). The TCI state may indicate a quasi-co-location (QCL) relationship between a downlink reference signal, such as a CSI-RS, and a DM-RS associated with a downlink control channel or data channel (e.g., the PDCCH or PDSCH, respectively).

[0082] In some embodiments, a UE may be configured with a list of up to M TCI state configurations using PDSCH configuration parameters to decode a physical downlink shared channel (PDSCH) according to a detected PDCCH with DCI intended for the UE and a given serving cell, where M may depend on UE capabilities. Each TCI state may include parameters for configuring a QCL relationship between one or two downlink reference signals and a DM-RS port of the PDSCH, a DM-RS port of the PDCCH, or a CSI-RS port of a CSI-RS resource. The quasi-collocation relationship may be configured by one or more RRC parameters. The quasi-collocation type corresponding to each DL RS may take one of the following values: 'QCL-Type A': {Doppler shift, Doppler spread, average delay, delay spread}; 'QCL-Type B': {Doppler shift, Doppler spread}; 'QCL-Type C': {Doppler shift, average delay}; or 'QCL-Type D': {spatial reception parameters}. The UE may receive an activation command (eg, MAC CE) used to map the TCI state to a codepoint in the DCI field.

[0083] FIG. 15 illustrates exemplary components of a user equipment and a base station for transmission and / or reception in accordance with some aspects of various exemplary embodiments of the present disclosure. All or a subset of the blocks and functions of FIG. 15 may be present in or performed by the base station 1505 and the user equipment 1500. An antenna 1510 may be used for transmission or reception of electromagnetic signals. The antenna 1510 may include one or more antenna elements and may be capable of different input / output antenna configurations, such as a multiple-input multiple output (MIMO) configuration, a multiple-input single-output (MISO) configuration, and a single-input multiple-output (SIMO) configuration. In some embodiments, the antenna 1510 may be capable of a massive MIMO configuration with tens or hundreds of antenna elements. The antenna 1510 may also be capable of other multi-antenna techniques, such as beamforming. In some examples, depending on the capabilities of the UE 1500 or the type of the UE 1500 (e.g., a low-complexity UE), the UE 1500 may only support a single antenna.

[0084] The transceiver 1520 may communicate bidirectionally via a wireless link, such as the antenna 1510, as described herein. For example, the transceiver 1520 may represent a wireless transceiver in a UE and may communicate bidirectionally with a wireless transceiver in a base station, or vice versa. The transceiver 1520 may include a modem for modulating packets and providing the modulated packets to the antenna 1510 for transmission, and for demodulating packets received from the antenna 1510.

[0085] The memory 1530 may include RAM and ROM. The memory 1530 may store computer-readable computer-executable code 1535, which includes instructions that, when executed, cause the processor to perform various functions described herein. In some examples, the memory 1530 may include, among other things, a basic input / output system (BIOS), which may control basic hardware or software operations such as interaction with peripheral components or devices.

[0086] The processor 1540 may include a hardware device with computing capabilities (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, discrete gate or transistor logic components, discrete hardware components, or any combination thereof). In some examples, the processor 1540 may be configured to operate a memory using a memory controller. In other examples, the memory controller may be integrated into the processor 1540. The processor 1540 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 1530) to cause the UE 1500 or the base station 1505 to perform various functions.

[0087] Central processing unit (CPU) 1550 may perform basic arithmetic, logical, control, and input / output (I / O) operations specified by computer instructions in memory 1530. User equipment 1500 and / or base station 1505 may include additional peripheral components such as a graphics processing unit (GPU) 1560 and a global positioning system (GPS) 1570. GPU 1560 is specialized circuitry for rapid manipulation and modification of memory 1530 to accelerate processing performance of user equipment 1500 and / or base station 1505. GPS 1570 may be used to enable location-based services or other services, for example, based on the geographic location of user equipment 1500.

[0088] In some examples, a non-terrestrial network (NTN) may provide non-terrestrial NR access to a UE through an NTN payload and an NTN gateway. A service link may exist between the NTN payload and the UE, and a feeder link may exist between the NTN gateway and the NTN payload.

[0089] In some examples, the NTN payload may transparently forward radio protocols received from the UE (over the service link) to the NTN gateway (over the feeder link), or vice versa: The following connections may be supported by the NTN payload, a gNB may serve multiple NTN payloads, and an NTN payload may be served by multiple gNBs:

[0090] In some examples, the NTN payload may change carrier frequency before retransmitting the carrier frequency on the service link, or vice versa (on the feeder link, respectively).

[0091] In some examples, for NTNs, in addition to the network identity, the following may apply, and the tracking area may correspond to a fixed geographical area: the respective mapping may be configured in the RAN; mapped cell ID.

[0092] In some examples, a non-geosynchronous orbit (NGSO) may include a low earth orbit (LEO) at an altitude of approximately 300 km to 1500 km, and a medium earth orbit (MEO) at an altitude of approximately 7000 km to 25000 km.

[0093] In some examples, three types of service links may be supported: Earth-fixed, provided by beam(s) that continuously cover the same geographic area at all times (e.g., in the case of GSO satellites); Quasi-Earth-fixed, provided by beam(s) that cover one geographic area for a limited period of time and a different geographic area for another period of time (e.g., in the case of NGSO satellites that generate steerable beams); and Earth-moving, provided by beam(s) whose coverage area moves across the Earth's surface (e.g., in the case of NGSO satellites that generate fixed and non-steerable beams).

[0094] In some examples, with NGSO satellites, gNBs may provide either quasi-earth fixed cell coverage or earth mobile cell coverage, while gNBs operating with GSO satellites may provide earth fixed cell coverage. In some examples, UEs supporting NTN may be GNSS capable.

[0095] In some instances, in the case of NGSO, switching a service link may refer to changing the satellite providing the service.

[0096] In some examples, the UE may be configured to report its timing advance: during random access procedures, in idle / inactive state; connected mode: using event-triggered reporting; in RRC re-establishment procedures, when an indicator is broadcast by the target cell's SI; for handovers, the UE should trigger a TA report if the target cell indicates this in the handover command.

[0097] In some examples, to accommodate long propagation delays, user plane procedures may be adapted as follows: for the downlink, HARQ feedback may be enabled or disabled for each HARQ process; for the uplink, the UE may be configured with HARQ mode A or B for each HARQ process; the maximum number of HARQ processes may be extended to 32; and the value ranges of MAC (e.g., sr-ProhibitTimer and configuredGrantTimer), RLC (i.e., t-Reassembly), and PDCP (i.e., discardTimer and t-reordering) layer timers may be extended.

[0098] In some examples, it may be up to the network implementation to ensure proper configuration of HARQ feedback (e.g., enabling or disabling) for HARQ processes used by the SPS configuration and HARQ mode for HARQ processes used by the CG configuration.

[0099] In some examples, if a logical channel is configured with an allowed HARQ mode, it may be mapped to an HARQ process with the same HARQ mode.

[0100] In some instances, to accommodate long propagation delays, some NR timing with DL-UL timing interaction is performed using two scheduling offsets, K offset and k mac This can be improved with the support of

[0101] In some examples, the timing relationships that need to be corrected for NTN using Koffset may be the transmission timing of DCI-scheduled PUSCH, including the transmission of channel state information (CSI) on the PUSCH; the transmission timing of random access response (RAR) grants or fallback RAR grant-scheduled PUSCHs; the timing of the first PUSCH transmission opportunity in a type 2 configuration grant; the transmission timing of HARQ-ACK on a physical uplink control channel (PUCCH), including HARQ-ACK on a PUCCH for message B (MsgB) in two-step random access; the transmission timing of a physical random access channel (PRACH) commanded by a PDCCH; the timing of adjustment of uplink transmission timing upon reception of a corresponding timing advance command; the transmission timing of an aperiodic sounding reference signal (SRS); and the timing of a CSI reference resource.

[0102] In some examples, upon network request, after AS security in connected mode is established, the UE may report its coarse location information (e.g., X most significant bits of its GNSS coordinates with approximately 2-km level accuracy) to the NG-RAN without receiving any prior explicit user consent. If "user consent" is available in the UE, the UE may report the UE's coarse location information. Otherwise, the UE may respond with "GNSS coarse location is not available." Periodic location reporting may be configured by the gNB to obtain UE location updates for the mobile UE in RRC_CONNECTED. This proposed text may be updated according to SA3 feedback.

[0103] In some examples, HARQ feedback disabling may be used to mitigate the impact of HARQ stalls on UE data rates.

[0104] In some examples, enabling / disabling HARQ feedback for downlink transmissions may be configurable at least per HARQ process via UE-specific RRC signaling.

[0105] In some examples, for a DL HARQ process with HARQ feedback disabled, the UE may not expect to receive another PDSCH or slot-aggregated PDSCH set scheduled for a given HARQ process, and may start until X after receiving the last PDSCH or slot-aggregated PDSCH for that HARQ process. In some examples, X = T_proc,1. In some examples, X may be X = max(T_proc,1,K1), where K1 may be the lowest value k1 if it is configured, or k1 = 0 otherwise. In some examples, the TBs of the two PDSCHs may be the same or different.

[0106] In some examples, X=T_proc,1, where X may be defined as the time from the end of reception of the last PDSCH or slot-aggregated PDSCH for a given HARQ process with feedback disabled to the start of PDCCH carrying of DCI scheduling another PDSCH or set of slot-aggregated PDSCHs for the given HARQ process.

[0107] In some examples, for HARQ feedback for each SPS PDSCH, the UE may follow the per-process configuration of HARQ feedback enabled / disabled for the associated HARQ process, except for the first SPS PDSCH after activation, if HARQ feedback for SPS activation is also enabled.

[0108] In some examples, enabling / disabling HARQ feedback may be configurable per HARQ process via UE-specific RRC signaling in the NR-NTN. In some examples, PDCCH monitoring and SPS activation may be improved when HARQ feedback is disabled.

[0109] In some examples, enabling / disabling HARQ feedback for downlink transmissions may be configurable per HARQ process via UE-specific RRC signaling.

[0110] In some examples, enabling / disabling of HARQ feedback in IoT-NTNs may be supported based on the number of repetitions per transmission.

[0111] In some examples, if HARQ feedback for an HARQ process is enabled, the UE may not be expected to receive another NPDCCH / MPDCCH carrying DCI scheduling the NPDSCH / PDSCH scheduled for a given HARQ process starting up to the round trip propagation delay after finishing transmitting the HARQ-ACK.

[0112] In some examples, there may be a potentially large throughput impact due to HARQ stalls caused by large RTT delays. In some examples, HARQ disabling may be used to eliminate HARQ stalls.

[0113] In some examples, for non-terrestrial based networks (NTNs), round trip time (RTT) delays can vary from tens to hundreds of milliseconds and can be long compared to terrestrial based networks. To accommodate the long RTTs and minimize throughput loss, the maximum number of supported HARQ processes may be extended (e.g., to 32 for both UL and DL) and / or feedback of some HARQ processes in the NR NTN may be disabled.

[0114] In some examples, for IoT NTNs where the HARQ mechanism is disabled, the peak rates for different scenarios may increase.

[0115] In some examples, when considering repetition, when a UE is configured with two HARQ processes, each scheduling one TB, there may be no stall issue, since the NPDSCH scheduling by the second HARQ process can fill the stalling of the NPDSCH scheduling by the first HARQ process.

[0116] In some instances of IoT NTN, the maximum data rate may be affected if a large number of iterations are used to improve the link budget.

[0117] In some examples, HARQ disabling in NR-NTN may be supported. HARQ disabling may provide the following benefits: reduced UE power consumption, increased throughput without increasing UE complexity, and improved resource utilization. In some examples, the main benefit of supporting HARQ disabling may be to resolve the HARQ stall problem.

[0118] In some examples, the HARQ stall problem may occur when an IoT UE is configured with only one HARQ process.

[0119] In some examples, the HARQ stall problem may occur when an IoT UE is configured with multiple HARQ processes.

[0120] In some examples, disabling HARQ may be supported, at least for IoT UEs that are configured / capable with only a single HARQ process.

[0121] In some examples, disabling HARQ may be configured by RRC signaling. A HARQ-enabled process may be used to transmit critical information. For IoT devices configured / capable with only one HARQ process, a semi-static configuration may not be flexible enough to ensure reliable reception of critical information. Dynamically disabling HARQ may be supported.

[0122] In some examples, dynamically disabling HARQ may be supported for IoT UEs that are configured / capable with at least one HARQ process.

[0123] In some examples, disabling HARQ feedback for DL ​​transmissions may avoid HARQ stalls due to long round-trip times. The available HARQ process transmission time may not fill the round-trip propagation time between the UE and the base station, resulting in HARQ stalls and limiting the UE's throughput throughout normal HARQ operation. While it has been noted that the base station may schedule a new transport block without waiting for an ACK / NACK to arrive, this may not provide the same benefits as disabling HARQ feedback. Furthermore, the UE may save transmit power for HARQ feedback. Furthermore, more UL data transmissions may be scheduled on resources that would have been used for HARQ feedback, resulting in higher UL throughput. Furthermore, for half-duplex UEs, more DL scheduling opportunities may be created that do not include HARQ feedback in the UL, which may increase DL throughput.

[0124] In some examples, enabling / disabling HARQ feedback for downlink transmissions may be configurable at least per HARQ process via UE-specific RRC signaling.

[0125] In some examples, if HARQ feedback is disabled, alternative long-term feedback may be considered to facilitate link adaptation.

[0126] In some examples, one or more of the following options may be considered to configure / indicate enablement / disablement in HARQ feedback for downlink transmission: per HARQ process via UE-specific RRC signaling, per HARQ process via SIB signaling explicitly indicated by DCI (e.g., new field or reuse of existing field), implicitly determined by existing configuration / indication parameters (e.g., number of repetitions, TBS), per HARQ process via MAC CE, or a combination of the above options.

[0127] In some examples, for DL ​​HARQ processes with HARQ feedback disabled, at least the following UE behaviors may be considered: The UE is not expected to receive another NPDCCH carrying DCI scheduling an NPDSCH for a given HARQ process, and this DCI starts until X ms after receiving the last NPDSCH for that HARQ process (e.g., X=12). The UE does not need to monitor the NPDCCH for a period of Y ms after receiving the last NPDSCH (e.g., Y=12). In some examples, there may be different UE behaviors for different UE categories (e.g., UEs with single / multiple HARQ processes).

[0128] In some examples, semi-persistent scheduling (SPS) may be configured by the RRC of the serving cell per BWP. In some cases, multiple allocations may be active simultaneously in the same BWP. In some implementations, DL SPS activation and deactivation may be independent between serving cells. For DL ​​SPS, DL allocations are provided by the PDCCH and may be stored or cleared based on L1 signaling indicating SPS activation or deactivation.

[0129] In some examples, when SPS is configured, RRC may configure the following parameters: cs-RNTI: CS-RNTI for activation, deactivation, and retransmission; nrofHARQ-Processes: number of HARQ processes configured for SPS; harq-ProcID-Offset: offset of HARQ processes for SPS; periodicity: periodicity of downlink allocation configured for SPS.

[0130] In some instances, when an SPS is released by a higher layer, all corresponding settings may be released.

[0131] In some examples, after the downlink allocations are configured for SPS, the MAC entity may determine that the Nth downlink allocation is: (numberOfSlotsPerFrame × SFN + slot number within the frame) = [(numberOfSlotsPerFrame × SFNstart time + slotstart time) + N × periodicity × numberOfSlotsPerFrame / 10] modulo (1024 × numberOfSlotsPerFrame) can be considered to be performed sequentially in slots Here, SFN start Time and slot start The time may be the SFN and slot, respectively, of the first transmission of the PDSCH at which the configured downlink allocation is (re)initialized.

[0132] In some examples, a downlink allocation for a PDCCH opportunity may be received for a serving cell on a PDCCH for the MAC entity's CS-RNTI or G-CS-RNTI. The NDI in the received HARQ information may be 0. If the PDCCH content indicates SPS deactivation, the MAC entity may clear the configured downlink allocation (if any) for this serving cell, and if the timeAlignmentTimer associated with the TAG containing the serving cell for which HARQ feedback is to be transmitted is running, the MAC entity may indicate an acknowledgment for the SPS deactivation to the physical layer. If the PDCCH content indicates SPS activation, the MAC entity may store the downlink allocation and associated HARQ information for this serving cell as a configured downlink allocation and initialize or reinitialize the configured downlink allocation for the serving cell to start within the associated PDSCH duration and recur according to the rules.

[0133] Enabling / disabling HARQ feedback has been considered as a solution to the HARQ stall problem in non-terrestrial networks. Enabling / disabling HARQ feedback may be per HARQ process or may be configurable for each HARQ process of multiple HARQ processes based on RRC configuration. A DCI scheduling a downlink TB may override the RRC configuration of enabling / disabling HARQ feedback. When a DCI schedules multiple TBs (e.g., a DCI for multiple TB scheduling, a DCI for SPS activation, etc.), existing solutions may result in degradation of UE and network performance. There is a need to improve existing solutions when a DCI schedules multiple downlink TBs (e.g., a DCI for multiple TB scheduling, a DCI for SPS activation, etc.). According to an exemplary embodiment, an existing solution is improved when a DCI schedules multiple downlink TBs (e.g., a DCI for multiple TB scheduling, a DCI for SPS activation, etc.).

[0134] In some examples, to set / indicate HARQ feedback enabling / disabling for downlink transmissions, the RRC configuration of HARQ feedback enabling / disabling per HARQ process may be the default mechanism for HARQ feedback enabling / disabling per HARQ process. The default RRC configuration of HARQ feedback enabling / disabling may be based on a bitmap, where each bit in the bitmap may be associated with an HARQ process number (e.g., a cell's HARQ process number), and the bit value may indicate whether HARQ feedback is enabled or disabled for the cell's HARQ process number (e.g., a bit value of zero may indicate that HARQ feedback for the HARQ process number is disabled, and a bit value of one may indicate that HARQ feedback for the cell's HARQ process number is enabled). The default mechanism for HARQ feedback enabling / disabling may be overridden by a downlink scheduling DCI (e.g., a DCI scheduling a downlink transmission / TB). The downlink scheduling DCI may indicate whether HARQ feedback for the received downlink transmission / TB is enabled / disabled and may override the default RRC configuration for the HARQ process associated with the downlink transmission / TB. In some examples, such an override mechanism (e.g., RRC configuration override by the scheduling DCI) may itself be configurable. For example, the UE may receive a configuration parameter indicating whether the DCI override of HARQ feedback over the default RRC configuration is configured or not.

[0135] In some examples, when enabling / disabling HARQ feedback for a downlink transmission / TB via a scheduling DCI (e.g., a DCI including scheduling information for the downlink transmission / TB) is configured / activated (e.g., based on receiving configuration parameters), the base station may not configure enabling / disabling per HARQ process via RRC, and enabling / disabling HARQ feedback may be based on the scheduling DCI.

[0136] In some examples, the DCI-based override mechanism may be applied to both semi-statically HARQ-enabled and -disabled processes. In some examples, the DCI-based override mechanism may be applied only to semi-statically HARQ-disabled processes. In some examples, the DCI-based override mechanism may be applied only to semi-statically HARQ-enabled processes.

[0137] In an exemplary embodiment, the UE may communicate with the base station using at least one cell provided by the base station, and the base station may transmit one or more messages (e.g., one or more RRC messages) that include configuration parameters for the at least one cell.

[0138] In an example embodiment, the UE may receive one or more messages (e.g., one or more RRC messages) including a configuration parameter. The configuration parameter may indicate whether HARQ feedback is enabled or disabled for multiple HARQ process numbers, including a first HARQ process number and a second HARQ process number. In some examples, the UE may be configured with multiple cells in the case of carrier aggregation, and the RRC may use separate configuration parameters to configure HARQ feedback enablement / disablement for different cells among the multiple cells. In some examples, the first HARQ process number and the second HARQ process number may be for the same cell. In some examples, the first HARQ process number and the second HARQ process number may be associated with different cells. In some examples, the UE may receive a configuration parameter (e.g., an RRC configuration parameter) indicating a bit string, where each bit in the bit string is associated with a HARQ process number and the bit value in the bit string indicates whether HARQ feedback is enabled or disabled for the HARQ process number. For example, the bit string may include a first bit associated with a first HARQ process number and a second bit associated with a second HARQ process number, where the first bit value may indicate whether HARQ feedback is enabled or disabled for the first HARQ process number, and the second bit value may indicate whether HARQ feedback is enabled or disabled for the second HARQ process number.

[0139] In an example embodiment, the UE may receive a DCI (e.g., a downlink scheduling DCI) indicating scheduling (e.g., including scheduling information therefor) of a first downlink TB and a second downlink TB. The first TB may be associated with a first HARQ process number, for example, based on the DCI (e.g., the DCI may indicate a first HARQ process number for the first TB) and / or based on radio resources associated with the first TB (e.g., if the first TB is a downlink SPS TB). The second TB may be associated with a second HARQ process number, for example, based on the DCI (e.g., the DCI may indicate a HARQ process number for the second TB) and / or based on radio resources associated with the second TB (e.g., if the second TB is a downlink SPS TB). In some examples, the first TB and the second TB may be downlink SPS TBs associated with an SPS configuration. The UE may receive SPS configuration parameters related to the SPS configuration, and the DCI may be an indicator activation of the DCI for activation of the SPS configuration. As shown in FIG. 18, in some examples, the first TB and the second TB may be received via the same first cell. The first HARQ process number and the second HARQ process number may be associated with the same first cell. As shown in FIG. 19, in some examples, the first TB and the second TB may be received via different cells, e.g., the first TB may be received via the first cell and the second TB may be received via the second cell. The first HARQ process number may be associated with the first cell, and the second HARQ process number may be associated with the second cell.

[0140] As shown in FIG. 16 , in an exemplary embodiment, the DCI may indicate one of enabling HARQ feedback and disabling HARQ feedback. For example, the DCI may include a field including a value indicating one of enabling HARQ feedback and disabling HARQ feedback (e.g., a value of 1 in the field indicating enabling HARQ feedback and a value of 0 in the field indicating disabling HARQ feedback). The UE may enable or disable HARQ feedback for the first TB and the second TB in response to receiving the DCI. The UE may enable or disable HARQ feedback for at least one of the first TB and the second TB based on the DCI (e.g., based on an indicator of HARQ feedback enablement / disablement in the DCI), regardless of an indicator in a configuration parameter (RRC configuration parameter). For example, the UE may enable or disable HARQ feedback for both the first TB and the second TB based on the DCI (e.g., based on an indicator of HARQ feedback enablement / disablement in the DCI), regardless of an indicator in a configuration parameter (RRC configuration parameter). For example, the UE may enable or disable HARQ feedback for one of the first TB and the second TB (e.g., an earlier one of the first and second TBs) based on the DCI (e.g., based on an indication of HARQ feedback enablement / disablement by the DCI), regardless of the indication by the configuration parameter (RRC configuration parameter). In some examples, the DCI may override the enablement / disablement of HARQ feedback for at least one of the first HARQ process number (associated with the first TB) and the second HARQ process number (associated with the second TB) by using the enablement / disablement indication of the DCI, regardless of the indication of HARQ feedback enablement / disablement by the RRC configuration parameter. The override of the RRC configuration of HARQ feedback enablement / disablement by the scheduling DCI may itself be configurable based on a configuration parameter.In some examples, the presence of a field in the scheduling DCI for enabling / disabling HARQ feedback may be configurable, for example, based on receipt of a configuration parameter indicating whether the scheduling DCI includes a field for enabling / disabling HARQ feedback.

[0141] As shown in FIG. 17 , in an exemplary embodiment, the DCI may separately indicate whether HARQ feedback is enabled or disabled for the first TB and the second TB scheduled by the DCI. The DCI may indicate whether HARQ feedback is enabled or disabled for the first TB, and separately, the DCI may indicate whether HARQ feedback is enabled or disabled for the second TB. For example, the DCI may include a first field and a second field. A first value of the first field may indicate one of enabling HARQ feedback and disabling HARQ feedback for the first TB. For example, the first field may include a first bit, and a 1 value of the first bit may indicate enabling HARQ feedback, and a 0 value of the first bit may indicate disabling HARQ feedback. A second value of the second field may indicate one of enabling HARQ feedback and disabling HARQ feedback for the second TB. For example, the second field may include a second bit, where a 1 value of the second bit may indicate enabling of HARQ feedback, and a 0 value of the second bit may indicate disabling of HARQ feedback. In some examples, the DCI may override the enabling / disabling of HARQ feedback for at least one of the first HARQ process number (associated with the first TB) and the second HARQ process number (associated with the second TB) by using the enabling / disabling indicator of the DCI, regardless of the HARQ feedback enabling / disabling indicator by the RRC configuration parameter. The overriding of the RRC configuration of HARQ feedback enabling / disabling by the scheduling DCI may itself be configurable based on a configuration parameter. In some examples, the presence of a field in the scheduling DCI for HARQ feedback enabling / disabling may be configurable, for example, based on receipt of a configuration parameter indicating whether the scheduling DCI includes a field for HARQ feedback enabling / disabling.

[0142] Based on enabling or disabling of HARQ feedback for the first HARQ process number and / or the second HARQ process number in response to receiving the DCI, the UE may send HARQ feedback related to the first TB (e.g., based on enabling of HARQ feedback for the first HARQ process number in response to receiving the DCI) and / or may send HARQ feedback related to the second TB (e.g., based on disabling of HARQ feedback related to the second HARQ process number in response to receiving the DCI).

[0143] In an exemplary embodiment, a user equipment (UE) may use a method for hybrid automatic repeat request (HARQ) feedback in a non-terrestrial network. The user equipment (UE) may receive configuration parameters indicating whether HARQ feedback is enabled or disabled for each of a first HARQ process number and a second HARQ process number. The UE may receive downlink control information (DCI). The DCI may include scheduling information for a first transport block (TB) associated with the first HARQ process number and a second TB associated with the second HARQ process number. The DCI may indicate one of enabling HARQ feedback or disabling HARQ feedback. The UE may enable or disable HARQ feedback for the first TB and the second TB. The enabling or disabling of HARQ feedback for at least one of the first TB and the second TB may be based on an indicator in the DCI or may be independent of an indicator in the configuration parameters.

[0144] In some examples, a first hybrid automatic repeat request (HARQ) process number and a second HARQ process number may be associated with a first cell, and a first transport block (TB) and a second TB may be scheduled for reception via the first cell.

[0145] In some examples, a first hybrid automatic repeat request (HARQ) process number may be associated with a first cell, a second HARQ process number may be associated with a second cell, a first transport block (TB) may be scheduled for reception via the first cell, and a second TB may be scheduled for reception via the second cell.

[0146] In some examples, downlink control information (DCI) may include a field including a value indicating one of enabling hybrid automatic repeat request (HARQ) feedback or disabling HARQ feedback. In some examples, the field may include a first bit, and the value of the first bit indicates one of enabling hybrid automatic repeat request (HARQ) feedback or disabling HARQ feedback. In some examples, a 1 value of the first bit may indicate enabling hybrid automatic repeat request (HARQ) feedback. A 0 value of the first bit may indicate disabling HARQ feedback.

[0147] In some examples, downlink control information (DCI) may indicate an override of a configuration parameter.

[0148] In some examples, enabling or disabling HARQ feedback for the first transport block (TB) and the second TB is based on an indicator in the downlink control information (DCI), regardless of an indicator in the configuration parameters.

[0149] In some examples, enabling or disabling HARQ feedback for one of the first and second transport blocks (TBs) is based on a downlink control information (DCI) indicator, regardless of a configuration parameter indicator. In some examples, enabling or disabling for an earlier scheduled transport block (TB) between the first and second TBs may be based on a downlink control information (DCI) indicator, regardless of a configuration parameter indicator. In some examples, enabling or disabling Hybrid Automatic Repeat Request (HARQ) feedback for the other transport block may be based on a configuration parameter indicator.

[0150] In some examples, the UE may transmit at least one of a first hybrid automatic repeat request (HARQ) feedback associated with a first transport block (TB) and a second HARQ feedback associated with a second TB based on HARQ feedback being enabled for the first TB and the second TB in response to receiving downlink control information (DCI).

[0151] In some examples, the downlink control information (DCI) may be for activation of a semi-persistent scheduling (SPS) configuration. In some examples, the UE may receive semi-persistent scheduling (SPS) configuration parameters for the SPS configuration. In some examples, a first transport block (TB) and a second TB may be associated with the semi-persistent scheduling (SPS) configuration.

[0152] In some examples, a UE may receive a first transport block (TB) and a second TB.

[0153] In some examples, the configuration parameter may indicate a bit string including a first bit and a second bit. The first bit may be associated with a first hybrid automatic repeat request (HARQ) process number, and the second bit may be associated with a second HARQ process number. The values ​​of the first bit and the second bit may indicate whether HARQ feedback is enabled or disabled for the first HARQ process number and the second HARQ process number, respectively.

[0154] In some examples, the configuration parameters may be radio resource control (RRC) configuration parameters.

[0155] In some examples, the configuration parameters may include a first parameter indicating that overriding hybrid automatic repeat request (HARQ) feedback by downlink control information is enabled.

[0156] In some examples, the configuration parameters include a first parameter indicating the presence of at least one field for enabling hybrid automatic repeat request (HARQ) feedback or disabling HARQ feedback in downlink control information (DCI) for scheduling.

[0157] In an exemplary embodiment, a user equipment (UE) may use a method for hybrid automatic repeat request (HARQ) feedback in a non-terrestrial network. The UE may receive configuration parameters indicating whether HARQ feedback is enabled or disabled for each of a first HARQ process number and a second HARQ process number. The UE may receive downlink control information (DCI). The DCI may include scheduling information for a first transport block (TB) associated with the first HARQ process number and a second TB associated with the second HARQ process number. The DCI may indicate whether HARQ feedback is enabled or disabled for the first TB. The DCI may indicate whether HARQ feedback is enabled or disabled for the second TB. The UE may enable or disable HARQ feedback for the first TB based on an indicator in the DCI, regardless of an indicator in the configuration parameter. The UE may enable or disable HARQ feedback for the second TB based on an indicator in the DCI, regardless of an indicator in the configuration parameter.

[0158] In some examples, a first hybrid automatic repeat request (HARQ) process number and a second HARQ process number may be associated with a first cell, and a first transport block (TB) and a second TB may be scheduled for reception via the first cell.

[0159] In some examples, a first hybrid automatic repeat request (HARQ) process number may be associated with a first cell, a second HARQ process number may be associated with a second cell, a first transport block (TB) may be scheduled for reception via the first cell, and a second TB may be scheduled for reception via the second cell.

[0160] In some examples, downlink control information (DCI) may include a first field including a first value indicating one of enabling hybrid automatic repeat request (HARQ) feedback or disabling HARQ feedback for a first transport block (TB), and a second field including a second value indicating one of enabling HARQ feedback or disabling HARQ feedback for a second TB. In some examples, the first field may include a first bit, where the value of the first bit indicates one of enabling hybrid automatic repeat request (HARQ) feedback or disabling HARQ feedback for the first transport block (TB). The second field may include a second bit, where the value of the second bit indicates one of enabling HARQ feedback or disabling HARQ feedback for the second TB. In some examples, a 1 value of the first bit may indicate enabling hybrid automatic repeat request (HARQ) feedback for the first transport block (TB). A 0 value of the first bit may indicate disabling HARQ feedback for the first TB. In some examples, a 1 value for the second bit may indicate enabling of Hybrid Automatic Repeat Request (HARQ) feedback for the second transport block (TB), and a 0 value for the second bit may indicate disabling of HARQ feedback for the second TB.

[0161] In some examples, downlink control information (DCI) may indicate an override of a configuration parameter.

[0162] In some examples, the UE may transmit at least one of a first hybrid automatic repeat request (HARQ) feedback associated with a first transport block (TB) and a second HARQ feedback associated with a second TB based on HARQ feedback being enabled or disabled for the first TB and the second TB in response to receiving downlink control information (DCI).

[0163] In some examples, the downlink control information (DCI) may be for activation of a semi-persistent scheduling (SPS) configuration. In some examples, the UE may receive semi-persistent scheduling (SPS) configuration parameters for the SPS configuration. In some examples, a first transport block (TB) and a second TB may be associated with the semi-persistent scheduling (SPS) configuration.

[0164] In some examples, a UE may receive a first transport block (TB) and a second TB.

[0165] In some examples, the configuration parameter may indicate a bit string including a first bit and a second bit. The first bit may be associated with a first hybrid automatic repeat request (HARQ) process number, and the second bit may be associated with a second HARQ process number. The values ​​of the first bit and the second bit may indicate whether HARQ feedback is enabled or disabled for the first HARQ process number and the second HARQ process number, respectively.

[0166] In some examples, the configuration parameters may be radio resource control (RRC) configuration parameters.

[0167] In some examples, the configuration parameters may include a first parameter indicating that overriding hybrid automatic repeat request (HARQ) feedback by downlink control information is enabled.

[0168] In some examples, the configuration parameters include a first parameter indicating the presence of at least one field for enabling hybrid automatic repeat request (HARQ) feedback or disabling HARQ feedback in downlink control information (DCI) for scheduling.

[0169] The example blocks and modules described in this disclosure with respect to various example embodiments may be implemented or performed by a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. Examples of general-purpose processors include, but are not limited to, a microprocessor, any conventional processor, controller, microcontroller, or state machine. In some examples, a processor may be implemented using a combination of devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in combination with a DSP core, or any other such configuration).

[0170] The functions described in this disclosure may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. Instructions or code may be stored on or transmitted to a computer-readable medium to implement the functions. Other examples for implementing the functions disclosed herein are also within the scope of this disclosure. The functions may be implemented through elements that are physically co-located, or through elements that are distributed (e.g., at various locations), including distribution such that portions of the functions are implemented in different physical locations.

[0171] Computer-readable media include, but are not limited to, non-transitory computer storage media. Non-transitory storage media may be accessed by a general-purpose computer or a special-purpose computer. Examples of non-transitory storage media include, but are not limited to, random access memory (RAM), read-only memory (ROM), electrically erasable programmable ROM (EEPROM), flash memory, compact disc (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, etc. Non-transitory media may be used to hold or store desired program code means (e.g., instructions and / or data structures) and may be accessed by a general-purpose computer or a special-purpose computer, or a general-purpose or special-purpose processor. In some examples, software / program code may be transmitted from a remote source (e.g., a website, server, etc.) using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio frequency, and microwave. In such examples, coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio frequency, and microwave are included within the definition of medium. Combinations of the above examples are also included within the scope of computer-readable media.

[0172] As used in this disclosure, the use of the word "or" in a list of items indicates an inclusive list. A list of items may be preceded by phrases such as "at least one of" or "one or more of." For example, a list of at least one of A, B, or C includes A, or B, or C, or AB (i.e., A and B), or AC, or BC, or ABC (i.e., A, B, and C). Also, as used in this disclosure, the phrase "based on" preceding a list of conditions should not be construed as "based only on" the set of conditions, but rather as "based at least in part on" the set of conditions. For example, a result described as "based on condition A" could be based on both condition A and condition B without departing from the scope of this disclosure.

[0173] As used herein, the terms "comprise," "include," or "contain" are used interchangeably, may have the same meaning, and should be construed as inclusive and open-ended. The term "comprise," "include," or "contain" may be used before a list of elements to indicate that at least all of the elements listed are present, but that other elements not in the list may also be present. For example, if A contains B and C, then both {B,C} and {B,C,D} are included within the scope of A.

[0174] While the present disclosure describes exemplary configurations in connection with the accompanying drawings, these exemplary configurations do not represent all possible implementations or all configurations within the scope of the present disclosure. The term "exemplary" should not be interpreted as "preferred" or "advantageous over other examples," but rather as "an example, instance, or example." By reading this disclosure, including the description of the embodiments and the drawings, those skilled in the art will understand that the technology disclosed herein can be implemented using alternative embodiments. Those skilled in the art will understand that the embodiments described herein, or specific features of the embodiments, can be combined to arrive at still other embodiments for implementing the technology described in the present disclosure. Therefore, the present disclosure is not limited to the examples and designs described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. 1. A method for Hybrid Automatic Repeat Request (HARQ) feedback in a non-terrestrial based network, the method comprising: receiving, by a user equipment (UE), a configuration parameter indicating whether HARQ feedback is enabled or disabled for each of a first Hybrid Automatic Repeat Request (HARQ) process number and a second HARQ process number; receiving downlink control information (DCI), the DCI comprising: comprising scheduling information for a first transport block (TB) associated with the first HARQ process number and a second TB associated with the second HARQ process number; and indicating one of enabling HARQ feedback or disabling HARQ feedback; enabling or disabling the HARQ feedback for the first TB and the second TB, wherein the enabling or disabling of the HARQ feedback for at least one of the first TB and the second TB is based on an indicator in the DCI, regardless of an indicator in the configuration parameter; A method comprising:

2. the first hybrid automatic repeat request (HARQ) process number and the second HARQ process number are associated with a first cell; 2. The method of claim 1, wherein the first transport block (TB) and the second TB are scheduled to be received via the first cell.

3. the first hybrid automatic repeat request (HARQ) process a second HARQ process number associated with a first cell and a second HARQ process number associated with a second cell; 2. The method of claim 1, wherein the first transport block (TB) is scheduled to be received via the first cell and the second TB is scheduled to be received via the second cell.

4. 2. The method of claim 1, wherein the downlink control information (DCI) includes a field containing a value indicating one of enabling the hybrid automatic repeat request (HARQ) feedback and disabling the HARQ feedback.

5. 5. The method of claim 4, wherein the field includes a first bit, a value of the first bit indicating one of enabling the Hybrid Automatic Repeat Request (HARQ) feedback and disabling the HARQ feedback.

6. a value of 1 for the first bit indicates enabling of the Hybrid Automatic Repeat Request (HARQ) feedback; The method of claim 5 , wherein a 0 value of the first bit indicates a disablement of the HARQ feedback.

7. The method of claim 1 , wherein the downlink control information (DCI) indicates an override of the configuration parameter.

8. 2. The method of claim 1, wherein the enabling or disabling of the Hybrid Automatic Repeat Request (HARQ) feedback for both the first transport block (TB) and the second TB is based on the indication in the Downlink Control Information (DCI), regardless of the indication in the configuration parameter.

9. 2. The method of claim 1, wherein the enabling or disabling of the Hybrid Automatic Repeat Request (HARQ) feedback for one of the first transport block (TB) and the second TB is based on the indication in the Downlink Control Information (DCI), regardless of the indication in the configuration parameter.

10. 10. The method of claim 9, wherein the enabling or disabling of the Hybrid Automatic Repeat Request (HARQ) feedback for an earlier scheduled TB between the first transport block (TB) and the second TB is based on the indication in the Downlink Control Information (DCI), regardless of the indication in the configuration parameter.

11. 10. The method of claim 9, wherein the enabling or disabling of the Hybrid Automatic Repeat Request (HARQ) feedback for the other transport block is based on the indication according to the configuration parameters.

12. 2. The method of claim 1, further comprising: transmitting at least one of a first Hybrid Automatic Repeat Request (HARQ) feedback associated with the first transport block (TB) and a second HARQ feedback associated with the second TB based on the HARQ feedback being enabled for at least one of the first TB and the second TB in response to receiving the downlink control information (DCI).

13. The method of claim 1, wherein the downlink control information (DCI) is for activation of a semi-persistent scheduling (SPS) configuration.

14. The method of claim 13 , further comprising receiving semi-persistent scheduling (SPS) configuration parameters for the SPS configuration.

15. 14. The method of claim 13, wherein the first transport block (TB) and the second TB are associated with the semi-persistent scheduling (SPS) configuration.

16. The method of claim 1 , further comprising receiving the first transport block (TB) and the second TB.

17. the configuration parameter represents a bit string including a first bit and a second bit; the first bit is associated with the first Hybrid Automatic Repeat Request (HARQ) process number, and the second bit is associated with the second HARQ process number; 2. The method of claim 1, wherein values ​​of the first bit and the second bit indicate whether the HARQ feedback is enabled or disabled for the first HARQ process number and the second HARQ process number, respectively.

18. The method of claim 1 , wherein the configuration parameters are radio resource control (RRC) configuration parameters.

19. 2. The method of claim 1, wherein the configuration parameters include a first parameter indicating that overriding of Hybrid Automatic Repeat Request (HARQ) feedback by the Downlink Control Information (DCI) is enabled.

20. 2. The method of claim 1, wherein the configuration parameters include a first parameter indicating the presence of at least one field for enabling Hybrid Automatic Repeat Request (HARQ) feedback or disabling HARQ feedback in scheduling downlink control information (DCI).

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