EP4233243A1

EP4233243A1 - Harq-ack feedback for multicast pdsch transmissions

Info

Publication number: EP4233243A1
Application number: EP21884104.7A
Authority: EP
Inventors: Debdeep CHATTERJEE; Alexei Davydov; Yingyang Li; Avik SENGUPTA; Gang Xiong
Original assignee: Intel Corp
Current assignee: Intel Corp
Priority date: 2020-10-23
Filing date: 2021-10-21
Publication date: 2023-08-30
Also published as: EP4233243A4; WO2022087620A1

Abstract

A User Equipment (UE) for operation in a fifth-generation new radio (5G NR) network is configured to provide hybrid automatic repeat request acknowledge (HARQ-ACK) feedback for reception of single-cell broadcast- multicast service (MBS) transmissions from a generation Node B (gNB) via a physical downlink shared channel (PDSCH) (i.e., multicast PDSCH transmissions) when the UE is in an RRC CONNECTED state. The UE may refrain from providing the HARQ-ACK feedback for the MBS transmissions when the UE is in an RRC IDLE or an RRC INACTIVE state.

Description

HARQ-ACK FEEDBACK FOR MULTICAST PDSCH TRANSMISSIONS

PRIORITY CLAIM

[0001] This application claims priority to United States Provisional Patent Application Serial No. 63/105,120, filed October 23, 2020 [reference number AD3357-Z] which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

[0002] Some embodiments relate to wireless networks including 3GPP (Third Generation Partnership Project) and fifth-generation (5G) networks including 5Gnew radio (NR) (or 5G-NR) networks. Some embodiments pertain to hybrid automatic repeat request (HARQ) acknowledgement (ACK) feedback for broadcast-multicast service (MBS) transmissions from a generation Node B (gNB) via a physical downlink shared channel (PDSCH) in a 5G NR networks.

BACKGROUND

[0003] Mobile communications have evolved significantly from early voice systems to today’s highly sophisticated integrated communication platform. With the increase in different types of devices communicating with various network devices, usage of 3GPP 5GNR systems has increased. The penetration of mobile devices (user equipment or UEs) in modem society has continued to drive demand for a wide variety of networked devices in many disparate environments. 5GNR wireless systems are forthcoming and are expected to enable even greater speed, connectivity, and usability, and are expected to increase throughput, coverage, and robustness and reduce latency and operational and capital expenditures. 5G-NR networks will continue to evolve based on 3 GPP LTE- Advanced with additional potential new radio access technologies (RATs) to enrich people’s lives with seamless wireless connectivity solutions delivering fast, rich content and services. As current cellular network frequency is saturated, higher frequencies, such as millimeter wave (mmWave) frequency, can be beneficial due to their high bandwidth. [0004] One issue with broadcast and multicast transmissions in 5G NR networks is reliability. Currently, no feedback mechanism exists for uplink feedback for broadcast and multicast transmissions in 5G NR networks.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] FIG. 1A illustrates an architecture of a network, in accordance with some embodiments.

[0006] FIG. IB and FIG. 1C illustrate a non-roaming 5G system architecture in accordance with some embodiments.

[0007] FIG. 2 is a functional block diagram of a wireless communication device in accordance with some embodiments.

DETAILED DESCRIPTION

[0008] The following description and the drawings sufficiently illustrate specific embodiments to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. Portions and features of some embodiments may be included in, or substituted for, those of other embodiments. Embodiments set forth in the claims encompass all available equivalents of those claims.

[0009] Some embodiments are directed to a User Equipment (UE) configured for operation in a 5G NR network. For reception of single-cell broadcast-multicast service (MBS) transmissions from a generation Node B (gNB) via a physical downlink shared channel (PDSCH) (i.e., multicast PDSCH transmissions), the UE may decode UE-specific radio-resource control (RRC) signalling to configure the UE to provide hybrid automatic repeat request acknowledge (HARQ-ACK) feedback for the MBS transmissions. In these embodiments, the UE may encode the HARQ-ACK feedback for the MBS transmissions for transmission via a physical uplink control channel (PUCCH) resource to the gNB when the UE is in an RRC_CONNECTED state. The UE may include memory to store an RRC configuration for the HARQ-ACK feedback for the MBS transmissions. In some embodiments, the RRC signalling configures the UE with a dedicated PUCCH resource from a PUCCH resource set for the HARQ-ACK feedback for the MBS transmissions. In these embodiments, the HARQ-ACK feedback may include ACK and negative acknowledge (NACK) feedback. These embodiments are described in more detail below.

[0010] In some embodiments, the UE may refrain from providing the HARQ-ACK feedback for the MBS transmissions when the UE is in an RRC IDLE or an RRC INACTIVE state (i.e., when the UE is not in the RRC CONNECTED state).

[0011] In some embodiments, the HARQ-ACK feedback for the MBS transmissions is a first uplink control information (UCI) type. In these embodiments, when the PUCCH resource carrying the HARQ-ACK feedback for the MBS transmissions overlaps in time with a PUCCH resource carrying another UCI type, the UE may drop one of the PUCCH resources depending on a priority order of the UCI types.

[0012] In some embodiments, the UE may decode signalling that dynamically switches on and switches off the HARQ-ACK feedback for the MBS transmissions for the UE when in the RRC CONNECTED state.

[0013] In some embodiments, to enable a NACK only feedback mode in which the HARQ-ACK feedback includes NACK only feedback for the MBS transmissions, the UE may decode RRC signalling from the gNB to enable HARQ-ACK feedback with NACK only transmissions on a shared PUCCH resource configured by the gNB for a group of more than one UE. In these embodiments, one of PUCCH format 0 or PUCCH format 1 may be used for the NACK only feedback mode.

[0014] In some embodiments, the UE is configured to use one of a Type 1 and a Type 2 HARQ-ACK codebook for the HARQ-ACK feedback for the MBS transmissions and a different HARQ-ACK codebook for HARQ-ACK feedback for unicast transmissions.

[0015] In some embodiments, when the PUCCH resource carrying the HARQ-ACK feedback for the MBS transmissions overlaps in time with a PUSCH, the UE may multiplex the HARQ-ACK feedback on the PUSCH. [0016] In some embodiments, upon transition from an RRC IDLE or an RRC INACTIVE state to the RRC CONNECTED state, the UE may provide the HARQ-ACK feedback for the MBS transmissions in accordance with on the stored RRC configuration for the HARQ-ACK feedback for the MBS transmissions.

[0017] In some embodiments, upon transition from an RRC IDLE or an RRC INACTIVE state to the RRC CONNECTED state, the UE may provide the HARQ-ACK feedback for the MBS transmissions, in accordance with on the stored RRC configuration for HARQ-ACK feedback for the MBS transmissions when conditions are met. In some of these embodiments, the UE may be configured to refrain from providing the HARQ-ACK feedback for the MBS transmissions when the conditions are not met. In these embodiments, the conditions are met when: the UE is still camping a same cell when last in the RRC CONNECTED state; a difference in DL RSRP from when the UE was last in the RRC CONNECTED state is less than a configured RSRP threshold; and a time since the UE was last in the RRC_CONNECTED state is less than a configured time threshold.

[0018] In some embodiments, when the PUCCH resource carrying the HARQ-ACK feedback for the MBS transmissions overlaps in time with a PUCCH resource carrying HARQ-ACK feedback for a unicast transmission, the UE may drop the PUCCH carrying the HARQ-ACK feedback for the MBS transmissions.

[0019] In some embodiments, when the UE is in an RRC IDLE or an RRC INACTIVE state, the UE may refrain from providing the HARQ-ACK feedback via the PUCCH resource for the MBS transmissions and may provide NACK only feedback via a PRACH using one or more PRACH preambles. In these embodiments, the UE may provide only NACK feedback on the PRACH and does not provide HARQ-ACK.

[0020] Some embodiments are directed to a non-transitory computer- readable storage medium that stores instructions for execution by processing circuitry to perform operations to configure a UE to provide hybrid automatic repeat request acknowledge (HARQ-ACK) feedback for reception of single-cell broadcast-multicast service (MBS) transmissions from a generation Node B (gNB) via a physical downlink shared channel (PDSCH) when the UE is in an RRC CONNECTED state.

[0021] Some embodiments are directed to a generation node B (gNB) configured for operation in a 5G NR network. In these embodiments, for singlecell broadcast-multicast service (MBS) transmissions via a PDSCH to a plurality of UEs, the gNB is configured to encode UE-specific RRC signalling to configure the UEs of the plurality that are in an RRC CONNECTED state for HARQ-ACK feedback, the HARQ-ACK feedback for the MBS transmissions. The gNB may decode the HARQ-ACK feedback for the MBS transmissions from the UEs, received via a PUCCH resource. These embodiments are described in more detail below.

[0022] In some embodiments, the RRC signalling configures the UEs with a dedicated PUCCH resource from a PUCCH resource set for the HARQ- ACK feedback for the MBS transmissions. The HARQ-ACK feedback may include positive ACK and negative acknowledge (NACK) feedback. In these embodiments, the gNB does not expect HARQ-ACK feedback for the MBS transmissions when the UEs are in an RRC IDLE or an RRC INACTIVE state. These embodiments are described in more detail below.

[0023] FIG. 1 A illustrates an architecture of a network in accordance with some embodiments. The network 140 A is shown to include user equipment (UE) 101 and UE 102. The UEs 101 and 102 are illustrated as smartphones (e.g., handheld touchscreen mobile computing devices connectable to one or more cellular networks) but may also include any mobile or non-mobile computing device, such as Personal Data Assistants (PDAs), pagers, laptop computers, desktop computers, wireless handsets, drones, or any other computing device including a wired and/or wireless communications interface. The UEs 101 and 102 can be collectively referred to herein as UE 101, and UE 101 can be used to perform one or more of the techniques disclosed herein.

[0024] Any of the radio links described herein (e.g., as used in the network 140 A or any other illustrated network) may operate according to any exemplary radio communication technology and/or standard. [0025] LTE and LTE- Advanced are standards for wireless communications of high-speed data for UE such as mobile telephones. In LTE- Advanced and various wireless systems, carrier aggregation is a technology according to which multiple carrier signals operating on different frequencies may be used to carry communications for a single UE, thus increasing the bandwidth available to a single device. In some embodiments, carrier aggregation may be used where one or more component carriers operate on unlicensed frequencies.

[0026] Embodiments described herein can be used in the context of any spectrum management scheme including, for example, dedicated licensed spectrum, unlicensed spectrum, (licensed) shared spectrum (such as Licensed Shared Access (LSA) in 2.3-2.4 GHz, 3.4-3.6 GHz, 3.6-3.8 GHz, and further frequencies and Spectrum Access System (SAS) in 3.55-3.7 GHz and further frequencies).

[0027] Embodiments described herein can also be applied to different Single Carrier or OFDM flavors (CP-OFDM, SC-FDMA, SC-OFDM, filter bank-based multicarrier (FBMC), OFDMA, etc.) and in particular 3GPP NR (New Radio) by allocating the OFDM carrier data bit vectors to the corresponding symbol resources.

[0028] In some embodiments, any of the UEs 101 and 102 can comprise an Intemet-of-Things (loT) UE or a Cellular loT (CIoT) UE, which can comprise a network access layer designed for low-power loT applications utilizing short-lived UE connections. In some embodiments, any of the UEs 101 and 102 can include a narrowband (NB) loT UE (e.g., such as an enhanced NB- loT (eNB-IoT) UE and Further Enhanced (FeNB-IoT) UE). An loT UE can utilize technologies such as machine-to-machine (M2M) or machine-type communications (MTC) for exchanging data with an MTC server or device via a public land mobile network (PLMN), Proximity -Based Service (ProSe) or device-to-device (D2D) communication, sensor networks, or loT networks. The M2M or MTC exchange of data may be a machine-initiated exchange of data. An loT network includes interconnecting loT UEs, which may include uniquely identifiable embedded computing devices (within the Internet infrastructure), with short-lived connections. The loT UEs may execute background applications (e.g., keep-alive messages, status updates, etc.) to facilitate the connections of the loT network.

[0029] In some embodiments, any of the UEs 101 and 102 can include enhanced MTC (eMTC) UEs or further enhanced MTC (FeMTC) UEs.

[0030] The UEs 101 and 102 may be configured to connect, e.g., communicatively couple, with a radio access network (RAN) 110. The RAN 110 may be, for example, an Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN), aNextGen RAN (NG RAN), or some other type of RAN. The UEs 101 and 102 utilize connections 103 and 104, respectively, each of which comprises a physical communications interface or layer (discussed in further detail below); in this example, the connections 103 and 104 are illustrated as an air interface to enable communicative coupling and can be consistent with cellular communications protocols, such as a Global System for Mobile Communications (GSM) protocol, a code-division multiple access (CDMA) network protocol, a Push-to- Talk (PTT) protocol, a PTT over Cellular (POC) protocol, a Universal Mobile Telecommunications System (UMTS) protocol, a 3GPP Long Term Evolution (LTE) protocol, a fifth-generation (5G) protocol, a New Radio (NR) protocol, and the like.

[0031] In an aspect, the UEs 101 and 102 may further directly exchange communication data via a ProSe interface 105. The ProSe interface 105 may alternatively be referred to as a sidelink interface comprising one or more logical channels, including but not limited to a Physical Sidelink Control Channel (PSCCH), a Physical Sidelink Shared Channel (PSSCH), a Physical Sidelink Discovery Channel (PSDCH), and a Physical Sidelink Broadcast Channel (PSBCH).

[0032] The UE 102 is shown to be configured to access an access point (AP) 106 via connection 107. The connection 107 can comprise a local wireless connection, such as, for example, a connection consistent with any IEEE 802.11 protocol, according to which the AP 106 can comprise a wireless fidelity (WiFi) router. In this example, the AP 106 is shown to be connected to the Internet without connecting to the core network of the wireless system (described in further detail below). [0033] The RAN 110 can include one or more access nodes that enable the connections 103 and 104. These access nodes (ANs) can be referred to as base stations (BSs), NodeBs, evolved NodeBs (eNBs), Next Generation NodeBs (gNBs), RAN nodes, and the like, and can comprise ground stations (e.g., terrestrial access points) or satellite stations providing coverage within a geographic area (e.g., a cell). In some embodiments, the communication nodes 111 and 112 can be transmission/reception points (TRPs). In instances when the communication nodes 111 and 112 are NodeBs (e.g., eNBs or gNBs), one or more TRPs can function within the communication cell of the NodeBs. The RAN 110 may include one or more RAN nodes for providing macrocells, e.g., macro-RAN node 111, and one or more RAN nodes for providing femtocells or picocells (e.g., cells having smaller coverage areas, smaller user capacity, or higher bandwidth compared to macrocells), e.g., low power (LP) RAN node 112.

[0034] Any of the RAN nodes 111 and 112 can terminate the air interface protocol and can be the first point of contact for the UEs 101 and 102. In some embodiments, any of the RAN nodes 111 and 112 can fulfill various logical functions for the RAN 110 including, but not limited to, radio network controller (RNC) functions such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management. In an example, any of the nodes 111 and/or 112 can be a new generation Node-B (gNB), an evolved node-B (eNB), or another type of RAN node.

[0035] The RAN 110 is shown to be communicatively coupled to a core network (CN) 120 via an SI interface 113. In embodiments, the CN 120 may be an evolved packet core (EPC) network, a NextGen Packet Core (NPC) network, or some other type of CN (e.g., as illustrated in reference to FIGS. 1B-1C). In this aspect, the SI interface 113 is split into two parts: the Sl-U interface 114, which carries traffic data between the RAN nodes 111 and 112 and the serving gateway (S-GW) 122, and the Sl-mobility management entity (MME) interface 115, which is a signaling interface between the RAN nodes 111 and 112 and MMEs 121.

[0036] In this aspect, the CN 120 comprises the MMEs 121, the S-GW 122, the Packet Data Network (PDN) Gateway (P-GW) 123, and a home subscriber server (HSS) 124. The MMEs 121 may be similar in function to the control plane of legacy Serving General Packet Radio Service (GPRS) Support Nodes (SGSN). The MMEs 121 may manage mobility embodiments in access such as gateway selection and tracking area list management. The HSS 124 may comprise a database for network users, including subscription-related information to support the network entities' handling of communication sessions. The CN 120 may comprise one or several HSSs 124, depending on the number of mobile subscribers, on the capacity of the equipment, on the organization of the network, etc. For example, the HSS 124 can provide support for routing/roaming, authentication, authorization, naming/addressing resolution, location dependencies, etc.

[0037] The S-GW 122 may terminate the SI interface 113 towards the RAN 110, and routes data packets between the RAN 110 and the CN 120. In addition, the S-GW 122 may be a local mobility anchor point for inter-RAN node handovers and also may provide an anchor for inter-3 GPP mobility. Other responsibilities of the S-GW 122 may include a lawful intercept, charging, and some policy enforcement.

[0038] The P-GW 123 may terminate an SGi interface toward a PDN. The P-GW 123 may route data packets between the EPC network 120 and external networks such as a network including the application server 184 (alternatively referred to as application function (AF)) via an Internet Protocol (IP) interface 125. The P-GW 123 can also communicate data to other external networks 131 A, which can include the Internet, IP multimedia subsystem (IPS) network, and other networks. Generally, the application server 184 may be an element offering applications that use IP bearer resources with the core network (e.g., UMTS Packet Services (PS) domain, LTE PS data services, etc.). In this aspect, the P-GW 123 is shown to be communicatively coupled to an application server 184 via an IP interface 125. The application server 184 can also be configured to support one or more communication services (e.g., Voice-over- Internet Protocol (VoIP) sessions, PTT sessions, group communication sessions, social networking services, etc.) for the UEs 101 and 102 via the CN 120.

[0039] The P-GW 123 may further be a node for policy enforcement and charging data collection. Policy and Charging Rules Function (PCRF) 126 is the policy and charging control element of the CN 120. In anon-roaming scenario, in some embodiments, there may be a single PCRF in the Home Public Land Mobile Network (HPLMN) associated with a UE's Internet Protocol Connectivity Access Network (IP-CAN) session. In a roaming scenario with a local breakout of traffic, there may be two PCRFs associated with a UE's IP- CAN session: a Home PCRF (H-PCRF) within an HPLMN and a Visited PCRF (V-PCRF) within a Visited Public Land Mobile Network (VPLMN). The PCRF 126 may be communicatively coupled to the application server 184 via the P- GW 123.

[0040] In some embodiments, the communication network 140 A can be an loT network or a 5G network, including 5G new radio network using communications in the licensed (5GNR) and the unlicensed (5GNR-U) spectrum. One of the current enablers of loT is the narrowband-IoT (NB-IoT). [0041] An NG system architecture can include the RAN 110 and a 5G network core (5GC) 120. The NG-RAN 110 can include a plurality of nodes, such as gNBs and NG-eNBs. The core network 120 (e.g., a 5G core network or 5GC) can include an access and mobility function (AMF) and/or a user plane function (UPF). The AMF and the UPF can be communicatively coupled to the gNBs and the NG-eNBs via NG interfaces. More specifically, in some embodiments, the gNBs and the NG-eNBs can be connected to the AMF by NG- C interfaces, and to the UPF by NG-U interfaces. The gNBs and the NG-eNBs can be coupled to each other via Xn interfaces.

[0042] In some embodiments, the NG system architecture can use reference points between various nodes as provided by 3GPP Technical Specification (TS) 23.501 (e.g., V15.4.0, 2018-12). In some embodiments, each of the gNBs and the NG-eNBs can be implemented as a base station, a mobile edge server, a small cell, a home eNB, and so forth. In some embodiments, a gNB can be a master node (MN) and NG-eNB can be a secondary node (SN) in a 5G architecture.

[0043] FIG. IB illustrates a non-roaming 5G system architecture in accordance with some embodiments. Referring to FIG. IB, there is illustrated a 5G system architecture 140B in a reference point representation. More specifically, UE 102 can be in communication with RAN 110 as well as one or more other 5G core (5GC) network entities. The 5G system architecture 140B includes a plurality of network functions (NFs), such as access and mobility management function (AMF) 132, session management function (SMF) 136, policy control function (PCF) 148, application function (AF) 150, user plane function (UPF) 134, network slice selection function (NSSF) 142, authentication server function (AUSF) 144, and unified data management (UDM)Zhome subscriber server (HSS) 146. The UPF 134 can provide a connection to a data network (DN) 152, which can include, for example, operator services, Internet access, or third-party services. The AMF 132 can be used to manage access control and mobility and can also include network slice selection functionality. The SMF 136 can be configured to set up and manage various sessions according to network policy. The UPF 134 can be deployed in one or more configurations according to the desired service type. The PCF 148 can be configured to provide a policy framework using network slicing, mobility management, and roaming (similar to PCRF in a 4G communication system). The UDM can be configured to store subscriber profiles and data (similar to an HSS in a 4G communication system).

[0044] In some embodiments, the 5G system architecture 140B includes an IP multimedia subsystem (IMS) 168B as well as a plurality of IP multimedia core network subsystem entities, such as call session control functions (CSCFs). More specifically, the IMS 168B includes a CSCF, which can act as a proxy CSCF (P-CSCF) 162BE, a serving CSCF (S-CSCF) 164B, an emergency CSCF (E-CSCF) (not illustrated in FIG. IB), or interrogating CSCF (I-CSCF) 166B. The P-CSCF 162B can be configured to be the first contact point for the UE 102 within the IM subsystem (IMS) 168B. The S-CSCF 164B can be configured to handle the session states in the network, and the E-CSCF can be configured to handle certain embodiments of emergency sessions such as routing an emergency request to the correct emergency center or PSAP. The I-CSCF 166B can be configured to function as the contact point within an operator's network for all IMS connections destined to a subscriber of that network operator, or a roaming subscriber currently located within that network operator's service area. In some embodiments, the I-CSCF 166B can be connected to another IP multimedia network 170E (e.g., an IMS operated by a different network operator). [0045] In some embodiments, the UDM/HSS 146 can be coupled to an application server 160E, which can include a telephony application server (TAS) or another application server (AS). The AS 160B can be coupled to the IMS 168B via the S-CSCF 164B or the I-CSCF 166B.

[0046] A reference point representation shows that interaction can exist between corresponding NF services. For example, FIG. IB illustrates the following reference points: N1 (between the UE 102 and the AMF 132), N2 (between the RAN 110 and the AMF 132), N3 (between the RAN 110 and the UPF 134), N4 (between the SMF 136 and the UPF 134), N5 (between the PCF 148 and the AF 150, not shown), N6 (between the UPF 134 and the DN 152), N7 (between the SMF 136 and the PCF 148, not shown), N8 (between the UDM 146 and the AMF 132, not shown), N9 (between two UPFs 134, not shown), N10 (between the UDM 146 and the SMF 136, not shown), Ni l (between the AMF 132 and the SMF 136, not shown), N12 (between the AUSF 144 and the AMF 132, not shown), N13 (between the AUSF 144 and the UDM 146, not shown), N14 (between two AMFs 132, not shown), N15 (between the PCF 148 and the AMF 132 in case of a non-roaming scenario, or between the PCF 148 and a visited network and AMF 132 in case of a roaming scenario, not shown), N16 (between two SMFs, not shown), and N22 (between AMF 132 and NSSF 142, not shown). Other reference point representations not shown in FIG. IB can also be used.

[0047] FIG. 1C illustrates a 5G system architecture 140C and a servicebased representation. In addition to the network entities illustrated in FIG. IB, system architecture 140C can also include a network exposure function (NEF) 154 and a network repository function (NRF) 156. In some embodiments, 5G system architectures can be service-based and interaction between network functions can be represented by corresponding point-to-point reference points Ni or as service-based interfaces.

[0048] In some embodiments, as illustrated in FIG. 1C, service-based representations can be used to represent network functions within the control plane that enable other authorized network functions to access their services. In this regard, 5G system architecture 140C can include the following service-based interfaces: Namf 158H (a service-based interface exhibited by the AMF 132), Nsmf 1581 (a service-based interface exhibited by the SMF 136), Nnef 158B (a service-based interface exhibited by the NEF 154), Npcf 158D (a service-based interface exhibited by the PCF 148), aNudm 158E (a service-based interface exhibited by the UDM 146), Naf 158F (a service-based interface exhibited by the AF 150), Nnrf 158C (a service-based interface exhibited by the NRF 156), Nnssf 158A (a service-based interface exhibited by the NSSF 142), Nausf 158G (a service-based interface exhibited by the AUSF 144). Other service-based interfaces (e.g., Nudr, N5g-eir, and Nudsl) not shown in FIG. 1C can also be used.

[0049] In some embodiments, any of the UEs or base stations described in connection with FIGS. 1A-1C can be configured to perform the functionalities described herein.

[0050] Mobile communication has evolved significantly from early voice systems to today’s highly sophisticated integrated communication platform. The next generation wireless communication system, 5G, or new radio (NR) will provide access to information and sharing of data anywhere, anytime by various users and applications. NR is expected to be a unified network/system that targets to meet vastly different and sometimes conflicting performance dimensions and services. Such diverse multi-dimensional requirements are driven by different services and applications. In general, NR will evolve based on 3GPP LTE-Advanced with additional potential new Radio Access Technologies (RATs) to enrich people's lives with better, simple, and seamless wireless connectivity solutions. NR will enable everything connected by wireless and deliver fast, rich content and services.

[0051] Rel-15 NR systems are designed to operate on the licensed spectrum. The NR-unlicensed (NR-U), a short-hand notation of the NR-based access to unlicensed spectrum, is a technology that enables the operation of NR systems on the unlicensed spectrum.

[0052] Embodiments herein relate to 3GPP NR Rel-17 work related to support of broadcast and multicast services within a single cell mainly targeting groupcast operations for the purpose of critical communications and commercial use cases such as popular video/app downloads. [0053] The Rel-17 WID [1] has the following objectives with respect to physical layer enhancements to support reliability improvements in multicast and broadcast transmissions in NR:

[0054] Specify RAN basic functions for broadcast/ multicast for UEs in RRC CONNECTED state [RANI, RAN2, RAN3]:

[0055] Specify required changes to improve reliability of Broadcast/Multicast service (e.g., by UL feedback). The level of reliability should be based on the requirements of the application/service provided. [ RANI, RAN2]

[0056] Based on the above obj ective, it was agreed in RAN 1 -103E meeting to support HARQ feedback for NR MBS for RRC CONNECTED UEs. This disclosure provides solutions to support HARQ feedback for NR MBS for RRC CONNECTED and RRC IDLE/INACTIVE UEs.

[0057] This disclosure proposes HARQ feedback schemes and related configuration options for NR MBS for both RRC CONNECTED and RRC IDLE/INACTIVE UEs.

[0058] The new work item on NR Support of Multicast and Broadcast Services has the objective of providing support of broadcast and multicast services within a single NR cell mainly targeting groupcast operations for the purpose of critical communications and commercial use cases such as popular video/app downloads.

[0059] In Rel-13 LTE, the support of single cell multi cast/broadcast was introduced in the form of SC-PTM (single cell point-to-multipoint) [2], However, no mechanism for uplink feedback or reliability improvement was additionally specified.

[0060] In this disclosure HARQ feedback mechanisms for NR MBS are proposed.

[0061] In one embodiment of this disclosure, for NR multicast and broadcast operation, HARQ feedback can be configured on and off for UE in RRC CONNECTED, RRC IDLE or RRC INACTIVE mode. In another embodiment, HARQ-ACK feedback in response to multicast PDSCH may be limited to UEs in RRC CONNECTED mode and the configuration of HARQ on/off can be semi-static, provided via UE-specific RRC signaling. [0062] In another embodiment, for RRC INACTIVE or IDLE UEs, the UE can retain such configuration from RRC signaling in CONNECTED state. In a further example, HARQ-ACK feedback configuration provided to the UE via dedicated RRC configuration in prior CONNECTED state may be reused by a UE in RRC INACTIVE or RRC IDLE modes only when one or more of the following conditions are satisfied:

[0063] The UE is still camping on the same cell as when it was last in RRC CONNECTED mode;

[0064] The difference in the DL RSRP from when the UE was last in RRC CONNECTED mode is within a specified or configured threshold;

[0065] The time since the UE was in RRC CONNECTED state is within a specified or configured threshold.

[0066] In yet another embodiment, the RRC IDLE/INACTIVE UEs can be configured with HARQ feedback on or off through RMSI signaling. In an embodiment, RRC INACTIVE/IDLE UEs may transmit PUCCH with HARQ- ACK feedback using a timing advance (TA) value of 0, e.g., following DL timing. In a further example, for a RRC INACTIVE/IDLE UE, the HARQ-ACK feedback in response to multicast PDSCH is defined by NACK-only feedback and is carried by a configured PRACH format and using a preamble from a set of one or more PRACH preambles that may be configured for the corresponding PRACH format.

[0067] In another embodiment, the configuration of HARQ on/off for a multicast PDSCH can be dynamically indicated to the UEs through a single bit in the DCI scheduling the multicast PDSCH.

[0068] Note: In this disclosure, the terms “multicast PDSCH”, “group common PDSCH”, and “MBS PDSCH” are used interchangeably.

[0069] In an embodiment of this disclosure, for a MBS service, the same mode of HARQ-ACK feedback (e.g., either NACK-only or differentiating ACK and NACK) is configured for all RRC_CONNECTED and

RRC IDLE/INACTIVE UEs. Alternatively, for a MBS service, the mode of NACK-only is configured for RRC IDLE/INACTIVE UEs, while the mode of differentiating ACK and NACK is configured for RRC_CONNECTED UEs. [0070] In an embodiment of this disclosure, a RRC CONNECTED UE supports HARQ operation with both ACK and NACK feedback over a dedicated PUCCH resource from a PUCCH resource set configured by RRC signaling. In one example, the PUCCH resource indicator is common for all the UEs in the group receiving the multicast transmission but can point to different PUCCH resources based on configuration of the UE-specific PUCCH resource set.

[0071] In one embodiment of this disclosure, RRC CONNECTED and RRC IDLE/INACTIVE UEs support HARQ feedback with NACK only transmission on the PUCCH. In one example, for RRC CONNECTED UEs NACK only feedback mode can be enabled in an SFN like manner wherein multiple UEs transmit NACK only signal on a shared PUCCH resource. The gNB can configure a common PUCCH resource to the group of UEs. The common resource needs to be indicated by the same PRI and hence should be mapped to the same index for all UEs receiving the groupcast transmission. In another example, for RRC CONNECTED UEs without dedicated PUCCH resource configuration or RRC IDLE/INACTIVE UEs, the NACK only feedback mode can be supported on pre-defined cell-specific PUCCH resource set from which 4 bit-RMSI indication selects 16 cell-specific resources and DCI indicates the PUCCH resource using the PRI and starting CCE index used for receiving the scheduling PDCCH.

[0072] In an embodiment, RRC IDLE/INACTIVE UEs may be configured to report NACK-only based HARQ- ACK feedback using PUCCH resources that are separately configured for RRC CONNECTED UEs. Thus, even if configured via SIB signaling, PUCCH resources for RRC CONNECTED UEs may be provided separately from those for RRC INACTIVE/IDLE UEs.

[0073] In another embodiment, separate PUCCH resources for the NACK-only based HARQ-ACK feedback could be configured for a UE that is synchronized to gNB in uplink and a UE that is not synchronized to gNB in uplink. The above separate PUCCH resources may have different PUCCH formats. Specifically, a legacy PUCCH format may be configured for a UE synchronized in uplink, while a PRACH resource may be configured for a UE not synchronized in uplink. [0074] In one embodiment of this disclosure, PUCCH format 0 and 1 are supported for NACK only HARQ feedback. For PFO, only a single cyclic shift = 0 is used. For PUCCH format 1, only BPSK modulation with complex symbol corresponding to binary bit value 0 is used by setting = 0 [0075] In one embodiment of this disclosure, for RRC CONNECTED UEs, semi-static RRC signaling can be used to configure ACK/NACK feedback mode or NACK only feedback mode. In another embodiment, the configured PUCCH resource can additionally include the indication to the UE for NACK only transmission which tells the UE to transmit only NACK on the configured resource.

[0076] In one embodiment of this disclosure, for NR MBS, X number of additional HARQ process IDs are defined in addition to current number of unicast HARQ processes. In one example, the value of X can be 2. In another embodiment, NR MBS shares the 16 HARQ process defined in Rel-15 NR for unicast transmission. Further, which HARQ processes are used for NR MBS can be configured by higher layers via RRC signalling or predefined in the specification. For instance, the first Y HARQ process IDs within unicast HARQ processes can be used for NR MBS.

[0077] In case when NR MBS shares HARQ processes with unicast transmission, and when MBS retransmission is scheduled using PDSCH for unicast, e.g., scheduled by PDCCH with CRC scrambled with C-RNTI, one field in the DCI may be included to indicate whether the scheduled PDSCH is for MBS or unicast transmission. In another option, some known states in one or more existing fields in the DCI format 1 0, 1 1 or 1 2 may be used to indicate whether the scheduled PDSCH is for MBS or unicast transmission.

[0078] In one embodiment of this disclosure, NR MBS uses a separate Type 1 and Type 2 HARQ-ACK codebook compared to unicast transmission.

[0079] In another option, Type 1 and Type 2 HARQ-ACK codebook may include HARQ-ACK feedback of MBS transmission. Further, ordering of HARQ-ACK feedback for MBS transmission may be predefined in the specification. For example, HARQ-ACK feedback of MBS transmission may correspond to the MSB or LSB bits in the HARQ-ACK codebook. [0080] In another embodiment, if PUCCH resource carrying HARQ- ACK feedback for NR MBS overlaps in time with a PUCCH carrying HARQ ACK information for a unicast transmission, the PUCCH carrying the MBS HARQ feedback is dropped.

[0081] In another option, when PUCCH carrying HARQ-ACK feedback of MBS service overlaps with one or more PUCCHs carrying same or other UCI types, including CSI report and SR, and when NACK is used for HARQ-ACK feedback of MBS, PUCCH carrying HARQ-ACK feedback of MBS is dropped. Alternatively, whether to drop one or more PUCCHs may depend on the priority order of UCI type.

[0082] For instance, the priority order of UCI ordering may be defined as in a descending ordering as HARQ-ACK feedback of unicast transmission > HARQ-ACK feedback of MBS transmission > SR > CSI report, where HARQ- ACK feedback of unicast transmission is considered as highest order. In this case, when PUCCH carrying HARQ-ACK feedback of MBS overlaps with PUCCH carrying SR, UE shall transmit PUCCH carrying HARQ-ACK feedback of MBS and drop PUCCH carrying SR.

[0083] In another example, when both ACK and NACK are used for HARQ-ACK feedback of MBS transmission, the existing UCI multiplexing mechanism as defined in Rel-15 and Rel-16 may be reused in case of timedomain overlaps with PUSCH or PUCCH.

[0084] In another example, NACK is used for HARQ-ACK feedback of MBS transmission when the HARQ-ACK feedback is not overlapped with a PUSCH or PUCCH. Otherwise, in case of time-domain overlaps with a PUSCH or PUCCH a, the HARQ-ACK feedback of MBS transmission can be multiplexed with the PUSCH or PUCCH. The existing UCI multiplexing mechanism as defined in Rel-15 and Rel-16 may be reused. In the latter case, UE can report ACK or NACK based on the reception status of the MBS transmission.

[0085] In another embodiment, PUCCH resource carrying HARQ-ACK feedback of MBS transmission can be considered as lower priority. More specifically, when PUCCH resource carrying HARQ-ACK feedback of MBS transmission overlaps with PUSCH or PUCCH with higher priority, PUCCH resource carrying HARQ-ACK feedback of MBS transmission is dropped. [0086] It is expected that simultaneous reception of group common PDSCH and unicast PDSCH may be supported by a UE as an optional UE capability when the PDSCHs are multiplexed at least in frequency domain. In an embodiment, simultaneous reception of group common and unicast PDSCHs is supported only when the group common PDSCH is scheduled with a transport block size (TBS) less than a specified value TBSmax MBS. Alternatively, the value of TBSmax MBS may be reported by the UE as part of UE capability reporting, that may be reported per frequency band or band combination or per UE.

[0087] In another example, it is expected that simultaneous reception of MBS PDSCH and legacy broadcast/groupcast PDSCH may be supported by a UE as an optional UE capability when the PDSCHs are multiplexed at least in frequency domain. In an option, simultaneous reception of MBS and legacy broadcast/groupcast PDSCHs is supported only when the MBS PDSCH is scheduled with a TBS less than a specified value X. Alternatively, the value of X may be reported by the UE as part of UE capability reporting, that may be reported per frequency band or band combination or per UE. In another option, simultaneous reception of MBS and legacy broadcast/groupcast PDSCHs is supported only when the MBS PDSCH is scheduled with a TBS less than a value XI and the legacy broadcast/multicast PDSCH is scheduled with a TBS less than a value X2. XI and X2 can be the same. XI and X2 can be predefined or configured by high layer signaling or may be reported by the UE as part of UE capability reporting.

[0088] In an embodiment, the minimum UE processing time for processing of a group common PDSCH and transmission of PUCCH or PUSCH with HARQ-ACK feedback follows the minimum UE processing time per Capability #1 as defined in Rel-15 NR specifications. In another option, the minimum UE processing time for processing of a group common PDSCH and transmission of PUCCH or PUSCH with HARQ-ACK feedback is determined based on Capability #1 with an additional margin of ‘d_MBS’ symbols, where d_MBS = 1, 2, 3, etc. In a further example, the additional margin of ‘d_MBS’ symbols is applied only when the group common PDSCH may overlap with a unicast PDSCH with an overlap of at least one OFDM symbol.

[0089] [1] RP-193248, New Work Item on NR Support of Multicast and

Broadcast Services, Huawei, RAN#86, Sitges, Spain, December 2019.

[0090] [2] 3GPP TR 36.890 vl3.0.0, Study on Single Cell Point-to-

Multipoint Transmission (Release 13)

[0091] FIG. 2 illustrates a functional block diagram of a wireless communication device, in accordance with some embodiments. Wireless communication device 200 may be suitable for use as a UE or gNB configured for operation in a 5GNR network.

[0092] The communication device 200 may include communications circuitry 202 and a transceiver 210 for transmitting and receiving signals to and from other communication devices using one or more antennas 201. The communications circuitry 202 may include circuitry that can operate the physical layer (PHY) communications and/or medium access control (MAC) communications for controlling access to the wireless medium, and/or any other communications layers for transmitting and receiving signals. The communication device 200 may also include processing circuitry 206 and memory 208 arranged to perform the operations described herein. In some embodiments, the communications circuitry 202 and the processing circuitry 206 may be configured to perform operations detailed in the above figures, diagrams, and flows.

[0093] In accordance with some embodiments, the communications circuitry 202 may be arranged to contend for a wireless medium and configure frames or packets for communicating over the wireless medium. The communications circuitry 202 may be arranged to transmit and receive signals. The communications circuitry 202 may also include circuitry for modulation/demodulation, upconversion/downconversion, filtering, amplification, etc. In some embodiments, the processing circuitry 206 of the communication device 200 may include one or more processors. In other embodiments, two or more antennas 201 may be coupled to the communications circuitry 202 arranged for sending and receiving signals. The memory 208 may store information for configuring the processing circuitry 206 to perform operations for configuring and transmitting message frames and performing the various operations described herein. The memory 208 may include any type of memory, including non-transitory memory, for storing information in a form readable by a machine (e.g., a computer). For example, the memory 208 may include a computer-readable storage device, read-only memory (ROM), randomaccess memory (RAM), magnetic disk storage media, optical storage media, flash-memory devices and other storage devices and media.

[0094] In some embodiments, the communication device 200 may be part of a portable wireless communication device, such as a personal digital assistant (PDA), a laptop or portable computer with wireless communication capability, a web tablet, a wireless telephone, a smartphone, a wireless headset, a pager, an instant messaging device, a digital camera, an access point, a television, a medical device (e.g., a heart rate monitor, a blood pressure monitor, etc.), a wearable computer device, or another device that may receive and/or transmit information wirelessly.

[0095] In some embodiments, the communication device 200 may include one or more antennas 201. The antennas 201 may include one or more directional or omnidirectional antennas, including, for example, dipole antennas, monopole antennas, patch antennas, loop antennas, microstrip antennas, or other types of antennas suitable for transmission of RF signals. In some embodiments, instead of two or more antennas, a single antenna with multiple apertures may be used. In these embodiments, each aperture may be considered a separate antenna. In some multiple-input multiple-output (MIMO) embodiments, the antennas may be effectively separated for spatial diversity and the different channel characteristics that may result between each of the antennas and the antennas of a transmitting device.

[0096] In some embodiments, the communication device 200 may include one or more of a keyboard, a display, a non-volatile memory port, multiple antennas, a graphics processor, an application processor, speakers, and other mobile device elements. The display may be an LCD screen including a touch screen. [0097] Although the communication device 200 is illustrated as having several separate functional elements, two or more of the functional elements may be combined and may be implemented by combinations of software-configured elements, such as processing elements including digital signal processors (DSPs), and/or other hardware elements. For example, some elements may include one or more microprocessors, DSPs, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), radio-frequency integrated circuits (RFICs) and combinations of various hardware and logic circuitry for performing at least the functions described herein. In some embodiments, the functional elements of the communication device 200 may refer to one or more processes operating on one or more processing elements.

[0098] Examples:

[0099] Example 1 may include a method for HARQ-ACK feedback indication for multicast PDSCH reception by a group of UEs where UEs in the group are possibly in RRC CONNECTED mode or RRC IDLE/IN ACTIVE mode.

[00100] Example 2 may include the method of example 1 or some other example herein, wherein the HARQ feedback can be configured on and off. [00101] Example 3 may include the method of examples 1-2 or some other example herein, wherein the HARQ feedback may limited to RRC CONNECTED UEs and the configuration of HARQ feedback can be semi-static through UE specific RRC signaling.

[00102] Example 4 may include the method of examples 1-2 or some other example herein, wherein RRC INACTIVE or IDLE UEs can retain such configuration from a prior RRC CONNECTED mode indication for example when the UE is still camped on the same cell, has a Ll-RSRP difference below a configured threshold and the time since the UE was in RRC CONNECTED mode is below a configured threshold.

[00103] Example 5 may include the method of examples 1-2 or some other example herein, wherein the configuration can be through RMSI or dynamically via a bit in DCI. [00104] Example 6 may include the method of examples 1-5 or some other example herein, wherein the UEs can transmit HARQ feedback using a TA value of 0 e.g., following DL Timing.

[00105] Example 7 may include the method of examples 1-6 or some other example herein, wherein the feedback mode can be ACK/NACK based or NACK only for RRC CONNECTED UEs and NACK-only for

RRC INACTIVE/IDLE mode UEs and the mode of feedback is configurable to the UEs either explicitly by RRC or SIB or implicitly through PUCCH resource configuration which includes additionally the feedback mode.

[00106] Example 8 may include the method of example 7 or some other example herein, wherein the NACK only feedback can be provided over cellspecific PUCCH resource for RRC CONNECTED/IDLE/INACTIVE UEs and over UE specifically configured PUCCH resources for RRC CONNECTED UEs.

[00107] Example 9 may include the method of example 8 or some other example herein, wherein PUCCH format 0 and 1 can be used for NACK only feedback mode.

[00108] Example 10 may include the methods of examples 1-9 or some other example herein, wherein MBS specific HARQ process IDs can be configured, which may be in addition to the existing 16 HARQ processes for unicast transmission.

[00109] Example 11 may include the methods of examples 1-10 or some other example herein, wherein MBS uses separate HARQ-ACK codebook compared to unicast transmission.

[00110] Example 12 may include the methods of examples 1-11 or some other example herein, wherein PUCCH resource carrying the HARQ-ACK feedback for MBS has lower priority than unicast.

[00111] Example 13 may include the methods of examples 1-12 or some other example herein wherein the UE processing time for a group common PDSCH and transmission of PUCCH with HARQ-ACK feedback is determined based on UE processing time Capability 1 with a potentially additional margin for MBS when MBS PDSCH overlaps with unicast PDSCH. [00112] Example 14 may include a method comprising: receiving configuration information for HARQ feedback for receiving a multicast PDSCH; and receiving an indication of whether the HARQ feedback is on or off.

[00113] Example 15 may include the method of example 14 or some other example herein, further comprising turning off the HARQ feedback when the UE is in an RRC INACTIVE state and/or a RRC IDLE state.

[00114] Example 16 may include the method of example 15 or some other example herein, further comprising retaining the configuration information while the UE is in the RRC IN ACTIVE state and/or a RRC IDLE state and using the configuration information when the UE enters a RRC CONNECTED state.

[00115] Example 17 may include the method of example 14-16 or some other example herein, further comprising receiving the multicast PDSCH; and providing HARQ feedback or determining not to provide HARQ feedback based on the indication.

[00116] The Abstract is provided to comply with 37 C.F.R. Section 1.72(b) requiring an abstract that will allow the reader to ascertain the nature and gist of the technical disclosure. It is submitted with the understanding that it will not be used to limit or interpret the scope or meaning of the claims. The following claims are hereby incorporated into the detailed description, with each claim standing on its own as a separate embodiment.

Claims

CLAIMS What is claimed is:

1. An apparatus for User Equipment (UE) configured for operation in a fifth-generation new radio (5G NR) network, the apparatus comprising: processing circuitry; and memory, wherein for reception of broadcast-multicast service (MBS) transmissions from a generation Node B (gNB) via a physical downlink shared channel (PDSCH), the processing circuitry is configured to: decode UE-specific radio-resource control (RRC) signalling to configure the UE to provide hybrid automatic repeat request acknowledge (HARQ-ACK) feedback for the MBS transmissions; and encode the HARQ-ACK feedback for the MBS transmissions for transmission via a physical uplink control channel (PUCCH) resource to the gNB when the UE is in an RRC_CONNECTED state, wherein the memory is configured to store an RRC configuration for the HARQ-ACK feedback for the MBS transmissions.

2. The apparatus of claim 1, wherein the RRC signalling configures the UE with a dedicated PUCCH resource from a PUCCH resource set for the HARQ-ACK feedback for the MBS transmissions, and wherein the HARQ-ACK feedback includes ACK and negative acknowledge (NACK) feedback.

3. The apparatus of claim 2, wherein the processing circuitry is configured to refrain from providing the HARQ-ACK feedback for the MBS transmissions when the UE is in an RRC IDLE or an RRC INACTIVE state.

4. The apparatus of claim 3, wherein the HARQ-ACK feedback for the MBS transmissions is a first uplink control information (UCI) type, and wherein when the PUCCH resource carrying the HARQ-ACK feedback for the MBS transmissions overlaps in time with a PUCCH resource carrying another UCI type, the processing circuitry is configured to drop one of the PUCCH resources depending on a priority order of the UCI types.

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5. The apparatus of claim 3, wherein the processing circuitry is configured to decode signalling that dynamically switches on and switches off the HARQ-ACK feedback for the MBS transmissions for the UE when in the RRC CONNECTED state.

6. The apparatus of claim 1, wherein to enable a NACK only feedback mode in which the HARQ-ACK feedback includes NACK only feedback for the MBS transmissions, the processing circuitry is configured to decode RRC signalling from the gNB to enable HARQ-ACK feedback with NACK only transmissions on a shared PUCCH resource configured by the gNB for a group of more than one UE, and wherein one of PUCCH format 0 or PUCCH format 1 are used for the NACK only feedback mode.

7. The apparatus of claim 3, wherein the UE is configured to use one of a Type 1 and a Type 2 HARQ-ACK codebook for the HARQ-ACK feedback for the MBS transmissions and a different HARQ-ACK codebook for HARQ-ACK feedback for unicast transmissions.

8. The apparatus of claim 3, wherein when the PUCCH resource carrying the HARQ-ACK feedback for the MBS transmissions overlaps with a PUSCH, the processing circuitry is configured to multiplex the HARQ-ACK feedback on the PUSCH.

9. The apparatus of claim 3, wherein upon transition from an RRC IDLE or an RRC INACTIVE state to the RRC CONNECTED state, the processing circuitry is to configure the UE to provide the HARQ-ACK feedback for the MBS transmissions, in accordance with on the RRC configuration for the HARQ-ACK feedback for the MBS transmissions.

10. The apparatus of claim 9, wherein upon transition from an

RRC IDLE or an RRC INACTIVE state to the RRC CONNECTED state, the processing circuitry is to: configure the UE to provide the HARQ-ACK feedback for the MBS transmissions, in accordance with on the RRC configuration for HARQ-ACK feedback for the MBS transmissions when conditions are met, and configure the UE to refrain from providing the HARQ-ACK feedback for the MBS transmissions when the conditions are not met, wherein the conditions are met when: the UE is camping a same cell when last in the RRC CONNECTED state; a difference in DL RSRP from when the UE was last in the RRC CONNECTED state is less than a configured RSRP threshold; and a time since the UE was last in the RRC_CONNECTED state is less than a configured time threshold.

11. The apparatus of claim 3, wherein when the PUCCH resource carrying the HARQ-ACK feedback for the MBS transmissions overlaps in time with a PUCCH resource carrying HARQ-ACK feedback for a unicast transmission, the processing circuitry is configured to drop the PUCCH carrying the HARQ-ACK feedback for the MBS transmissions.

12. The apparatus of claim 3, wherein when the UE is in an RRC IDLE or an RRC INACTIVE state, the processing circuitry is configured to: refrain from providing the HARQ-ACK feedback via the PUCCH resource for the MBS transmissions; and provide NACK only feedback via a PRACH using one or more PRACH preambles.

13. A non-transitory computer-readable storage medium that stores instructions for execution by processing circuitry of a User Equipment (UE) for operation in a fifth-generation new radio (5G NR) network, wherein for reception of broadcast-multicast service (MBS) transmissions from a generation Node B (gNB) via a physical downlink shared channel (PDSCH), the processing circuitry is configured to: decode UE-specific radio-resource control (RRC) signalling to configure the UE to provide hybrid automatic repeat request acknowledge (HARQ-ACK) feedback for the MBS transmissions; encode the HARQ-ACK feedback for the MBS transmissions for transmission via a physical uplink control channel (PUCCH) resource to the gNB when the UE is in an RRC_CONNECTED state; and store an RRC configuration for the HARQ-ACK feedback for the MBS transmissions.

14. The non-transitory computer-readable storage medium of claim 13, wherein the RRC signalling configures the UE with a dedicated PUCCH resource from a PUCCH resource set for the HARQ-ACK feedback for the MBS transmissions, and wherein the HARQ-ACK feedback includes ACK and negative acknowledge (NACK) feedback.

15. The non-transitory computer-readable storage medium of claim 14, wherein the processing circuitry is configured to refrain from providing the HARQ-ACK feedback for the MBS transmissions when the UE is in an RRC IDLE or an RRC INACTIVE state.

16. The non-transitory computer-readable storage medium of claim 15, wherein the HARQ-ACK feedback for the MBS transmissions is a first uplink control information (UCI) type, and wherein when the PUCCH resource carrying the HARQ-ACK feedback for the MBS transmissions overlaps in time with a PUCCH resource carrying another UCI type, the processing circuitry is configured to drop one of the PUCCH resources depending on a priority order of the UCI types.

17. The non-transitory computer-readable storage medium of claim 15, wherein the processing circuitry is configured to decode signalling that dynamically switches on and switches off the HARQ-ACK feedback for the MBS transmissions for the UE when in the RRC CONNECTED state.

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18. The non-transitory computer-readable storage medium of claim 13, wherein to enable a NACK only feedback mode in which the HARQ-ACK feedback includes NACK only feedback for the MBS transmissions, the processing circuitry is configured to decode RRC signalling from the gNB to enable HARQ-ACK feedback with NACK only transmissions on a shared PUCCH resource configured by the gNB for a group of more than one UE, and wherein one of PUCCH format 0 or PUCCH format 1 are used for the NACK only feedback mode.

19. An apparatus for a generation node B (gNB) configured for operation in a fifth-generation new radio (5GNR) network, the apparatus comprising: processing circuitry; and memory, wherein for broadcast-multicast service (MBS) transmissions via a PDSCH to a plurality of UEs, the processing circuitry is configured to: encode RRC signalling to configure the UEs of the plurality that are in an RRC CONNECTED state for HARQ-ACK feedback, the HARQ-ACK feedback for the MBS transmissions; and decode the HARQ-ACK feedback for the MBS transmissions from the UEs, received via a PUCCH resource.

20. The apparatus of claim 19, wherein the RRC signalling configures the UEs with a dedicated PUCCH resource from a PUCCH resource set for the HARQ-ACK feedback for the MBS transmissions, and wherein the HARQ-ACK feedback includes ACK and negative acknowledge (NACK) feedback, and wherein the gNB does not expect HARQ-ACK feedback for the MBS transmissions when the UEs are in an RRC IDLE or an RRC INACTIVE state.

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