Management of multicast and broadcast services in semi-persistently scheduled radio resources

Abstract

An object of the present invention is to provide management of multicast and broadcast services in semi-persistent scheduling radio resources. A base station may implement a method for managing transmission of multicast and / or broadcast services (MBS) using semi-persistent scheduling (SPS), the method including: transmitting (1702) a configuration for receiving MBS data on SPS radio resources to a user equipment (UE); providing (1704) an indication to the UE to activate receiving the MBS data according to the configuration; and transmitting (1706) the MBS data to the UE according to the configuration.

Description

[Technical Field]

[0001] The present disclosure relates to wireless communications, and more particularly to enabling setup and / or release of semi-persistent scheduling (SPS) radio resources for transmission and / or reception of one or more multicast and / or broadcast services (MBS). [Background technology]

[0002] The background discussion provided herein is for purposes of generally presenting the contents of the present disclosure. To the extent described in this background section, the work of the presently named inventors, and aspects of this discussion that may not qualify as prior art at the time of filing, are not admitted expressly or impliedly as prior art to the present disclosure.

[0003] In telecommunications systems, the Packet Data Convergence Protocol (PDCP) sublayer of the radio protocol stack provides services such as user plane data transport, encryption, and integrity protection. For example, the PDCP layer defined for the Evolved Universal Terrestrial Radio Access (EUTRA) air interface (see 3GPP® specification TS 36.323) and New Radio (NR) (see 3GPP® specification TS 38.323) provides protocol data unit (PDU) ordering in the uplink direction (from a user device, also known as user equipment (UE), to a base station) and the downlink direction (from a base station to a UE). Additionally, the PDCP sublayer provides signaling radio bearer (SRB) services to the Radio Resource Control (RRC) sublayer. The PDCP sublayer also provides Data Radio Bearer (DRB) services to the Service Data Adaptation Protocol (SDAP) sublayer or protocol layers such as the Internet Protocol (IP) layer, the Ethernet protocol layer, and the Internet Control Message Protocol (ICMP) layer. Generally speaking, the UE and the base station can use the SRB to exchange RRC messages and non-access stratum (NAS) messages, and can use the DRB to transfer data on the user plane.

[0004] Base stations operating in accordance with fifth-generation (5G) New Radio (NR) requirements support significantly wider bandwidths than fourth-generation (4G) base stations. Accordingly, the Third Generation Partnership Project (3GPP®) proposed in Release 15 that user equipment units (UEs) support a 100 MHz bandwidth in Frequency Range 1 (FR1) and a 400 MHz bandwidth in Frequency Range 2 (FR2). Due to the relatively wide bandwidths of typical carriers, 3GPP® proposed in Release 17 that 5G NR base stations be capable of providing UEs with multicast and / or broadcast services (MBS), which may be useful in many content distribution applications, such as transparent IPv4 / IPv6 multicast distribution, IPTV, software distribution over wireless, group communications, IoT applications, V2X applications, and emergency messages related to public safety.

[0005] To provide multicast and / or broadcast services (MBS), a base station can configure multiple UEs with common frequency resources (CFRs) and a group-common physical downlink control channel (PDCCH) that constitutes a PDCCH. The base station can assign group-common radio network temporary identifiers (RNTIs) to these UEs to receive physical downlink shared channel (PDSCH) transmissions that include MBS data packets. The base station can then transmit downlink control information (DCI) with a cyclic redundancy check (CRC) scrambled by the group-common RNTI on the group-common PDCCH to schedule PDSCH transmissions that include MBS data packets.

[0006] Recently, 3GPP has proposed transmitting MBS data over semi-persistent scheduling (SPS) resources. However, it is not clear how a base station configures and manages SPS radio resources to transmit MBS data. Summary of the Invention [Means for solving the problem]

[0007] A base station and / or UE can implement the techniques of this disclosure to manage the transmission and reception of MBS using SPS. In particular, the base station can transmit a configuration for receiving MBS data on SPS radio resources (i.e., an MBS SPS configuration) to the UE. The base station can transmit the configuration to the UE on dedicated resources for the UE, or can multicast or broadcast the configuration to multiple UEs.

[0008] The base station also provides the UE with an instruction to activate receiving MBS data according to the configuration. In some implementations, receipt of the configuration itself activates the UE. For example, the configuration may include a combined information element or field that causes the UE to activate SPS radio resources to receive MBS data. In other implementations, the base station sends the instruction and the configuration separately to the UE but in the same message (e.g., in an RRC message such as an RRC reconfiguration message). In yet other implementations, the base station sends the configuration and the instruction to the UE in separate messages. For example, the base station may send the instruction as a command to activate receiving MBS data according to the configuration. Similar to the configuration, the base station can send the command either using unicast transmission to an individual UE or using multicast or broadcast transmission to multiple UEs. After activating the UE, the base station transmits the MBS data according to the configuration.

[0009] In either the command or the configuration, the base station may indicate resources on which the UE should transmit an acknowledgment for the command and / or MBS data. For example, if the base station transmits a specific configuration to the UE in a unicast transmission, the base station may include within the specific configuration a HARQ resource configuration for the UE to transmit the acknowledgment. For example, the HARQ resource configuration may include a time slot, a frequency resource, and / or a physical uplink control channel (PUCCH) format.

[0010] The command transmitted by the base station (i.e., the MBS SPS activation command) may have a different format from the command to activate the use of SPS radio resources to receive unicast data (i.e., the unicast SPS activation command). Alternatively, the MBS SPS activation command and the unicast SPS activation command may have the same format but include different values ​​of the SPS configuration index (also referred to throughout this specification as the “SPS index”). Furthermore, the UE may determine whether the command is an MBS SPS activation command or a unicast SPS activation command based on a radio network temporary identifier (RNTI) that descrambles a cyclic redundancy check (CRC) received with the command or scrambles a CRC calculated from the command. For example, the base station may transmit the MBS SPS activation command with a CRC scrambled using an RNTI associated with the MBS (e.g., a group RNTI) rather than an RNTI for an individual UE (e.g., a cell RNTI (c-RNTI)).

[0011] One exemplary embodiment of these techniques is a method implemented in a base station for managing transmission of multicast and / or broadcast services (MBS) using semi-persistent scheduling (SPS). The method may be executed by processing hardware and includes transmitting a configuration to a user equipment (UE) for receiving MBS data on SPS radio resources. The method further includes providing an indication to the UE to activate receiving the MBS data according to the configuration and transmitting the MBS data to the UE according to the configuration.

[0012] Another exemplary embodiment of these techniques is a base station that includes processing hardware and is configured to implement the above methods.

[0013] A further exemplary embodiment of these techniques is a method in a UE for managing reception of MBS data using SPS. The method may be executed by processing hardware and includes receiving, from a base station, a configuration for receiving MBS data on SPS resources. The method further includes determining that the UE activates reception of MBS data according to the configuration and receiving the MBS data from the base station according to the configuration.

[0014] Yet another exemplary embodiment of these techniques is a UE that includes processing hardware and is configured to implement the above methods. [Brief explanation of the drawings]

[0015] [Figure 1A] FIG. 1 is a block diagram of an example wireless communication system in which the RAN and / or UE implement the techniques of this disclosure for managing the transmission and reception of MBSs. [Figure 1B] 1B is a block diagram of an exemplary base station including a central unit (CU) and a distributed unit (DU) capable of operating in the system of FIG. 1A. [Figure 2] 1B is a block diagram of an example protocol stack for the UE of FIG. 1A to communicate with a base station. [Figure 3A] 1 is a diagram of an example message sequence in which a base station transmits (i.e., via multicast or broadcast) (i) an MBS SPS configuration and (ii) MBS data according to the SPS configuration to two UEs. [Figure 3B] FIG. 3B is a diagram of an example message sequence similar to that of FIG. 3A, but in which the base station transmits a first SPS configuration to a first UE using dedicated resources for the first UE and a second SPS configuration to a second UE using dedicated resources for the second UE. [Figure 4] FIG. 3B is a diagram of an example message sequence similar to that of FIG. 3A, but in which the base station periodically rebroadcasts the SPS activation command based on the periodicity of the SPS. [Figure 5] 10 is a diagram of an example message sequence in which a base station sends an RRC message including an MBS SPS configuration and an SPS activation indication to two UEs. [Figure 6A] 10 is a diagram of an example message sequence in which a base station receives a hybrid automatic repeat request (HARQ) acknowledgement from a UE in response to an MBS SPS activation command. [Figure 6B] 10 is a diagram of an example message sequence in which a base station receives a medium access control (MAC) protocol data unit (PDU) including an acknowledgment from a UE in response to an MBS SPS activation command. [Figure 7] 10 is a diagram of an example message sequence in which a base station receives a HARQ acknowledgement from a UE in response to an MBS data packet transmitted on SPS resources. [Figure 8] FIG. 10 is a diagram of an example message sequence in which a base station sends to a UE (i) an MBS SPS configuration that schedules SPS radio resources for multicasting MBS data packets, and (ii) a unicast SPS configuration that schedules SPS radio resources for transmitting unicast data packets. [Figure 9]FIG. 10 is a diagram of an example message sequence in which a base station sends to a UE (i) a first SPS activation command having a first SPS index to activate the UE to receive MBS data packets using SPS, and (ii) a second SPS activation command having a second SPS index to activate the UE to receive unicast data packets using SPS. [Figure 10A] 1 is a flow diagram of an example method for transmitting MBS data packets to multiple UEs using SPS that may be implemented by a base station. [Figure 10B] 10B is a flow diagram of an exemplary method similar to that of FIG. 10A, but in which a base station transmits a particular SPS configuration to each of a plurality of UEs. [Figure 11A] 10 is a flow diagram of an example method that may be implemented by a base station for retransmitting an SPS activation command in response to not receiving an acknowledgment to an initial SPS activation command. [Figure 11B] 10 is a flow diagram of an example method that may be implemented by a base station for retransmitting an SPS activation command in response to not receiving an acknowledgment for MBS data. [Figure 12] 1 is a flow diagram of an example method for transmitting an SPS activation command and a cyclic redundancy check (CRC) to a UE that may be implemented by a base station. [Figure 13A] 1 is a flow diagram of an example method that may be implemented by a base station for formatting an SPS activation command based on whether the SPS activation command is for transmitting an MBS or for transmitting unicast data. [Figure 13B] 1 is a flow diagram of an example method that may be implemented by a base station for configuring fields of an SPS activation command based on whether the SPS activation command is for transmitting an MBS or for transmitting unicast data. [Figure 14]10 is a flow diagram of an example method that may be implemented by a base station for determining whether to send a separate SPS configuration and an SPS activation command. [Figure 15A] 1 is a flow diagram of an example method that may be implemented by a UE for determining whether an SPS activation command enables receiving unicast data or MBS data based on a CRC received along with the SPS activation command. [Figure 15B] 1 is a flow diagram of an example method that may be implemented by a UE for determining whether an SPS activation command enables receiving unicast data or MBS data based on the format of the SPS activation command. [Figure 15C] 1 is a flow diagram of an example method that may be implemented by a UE for determining whether an SPS activation command enables receiving unicast data or MBS data based on a field value of the SPS activation command. [Figure 16] FIG. 10 is a flow diagram of an example method that may be implemented by a UE to determine whether to activate receiving data according to an SPS configuration based on whether the SPS configuration is for unicast or MBS. [Figure 17] 10 is a flow diagram of an example method for managing an SPS for an MBS that may be implemented by a base station. [Figure 18] 10 is a flow diagram of an example method for managing an SPS for an MBS that may be implemented by a UE. DETAILED DESCRIPTION OF THE INVENTION

[0016] Generally speaking, the techniques of this disclosure enable UEs to receive MBS information via radio resources allocated by a base station in a RAN. To this end, the base station can configure different radio resources in one or more overlapping cells to multicast or broadcast MBS data (and associated control information) to one or more UEs on the downlink (DL) and / or unicast non-MBS data (and associated control information). Note that "transmission" by a base station may interchangeably refer to "multicast," "broadcast," and / or "unicast." The base station can also unicast MBS data (and associated control information) to the UEs on a dedicated DRB for the UE. One or more UEs can transmit non-MBS data to the base station on the uplink (UL).

[0017] Thus, a base station of the present disclosure can configure one or more radio bearers to transmit MBS information (i.e., MBS data packets and / or control information) to a UE. The radio bearer carrying the MBS information to the UE can be a unicast DRB (i.e., a dedicated DRB for the UE) or a multicast DRB (i.e., a DRB that can be shared by multiple UEs, also referred to as an MBS radio bearer or MRB). For example, the base station can send unicast or multicast configuration parameters to the UE to configure the UE to receive MBS information via a unicast or multicast DRB, respectively. As used in this disclosure, the term DRB may refer to a unicast or multicast DRB unless otherwise specified.

[0018] 1A illustrates an example wireless communication system 100 in which the MBS operation techniques of the present disclosure may be implemented. The wireless communication system 100 includes a UE 102A and a UE 102B, as well as base stations 104, 106A, and 106B of a radio access network (RAN) (e.g., RAN 105) connected to a core network (CN) 110. For ease of reading, the UE 102 is used herein to represent the UE 102A, the UE 102B, or both the UE 102A and the UE 102B, unless otherwise specified. The base stations 104, 106A, and 106B may be any suitable type or types of base stations, such as, for example, an evolved Node B (eNB), a next-generation eNB (ng-eNB), or a 5G Node B (gNB). As a more specific example, the base station 104 may be an eNB or a gNB, and the base stations 106A and 106B may be gNBs.

[0019] The base station 104 supports cell 124, the base station 106A supports cell 126A, and the base station 106B supports cell 126B. Cell 124 partially overlaps with both cells 126A and 126B such that the UE 102 can be within range to communicate with the base station 104 while simultaneously being within range to communicate with either base station 106A or 106B (or within range to detect or measure signals from both base stations 106A and 106B). The overlap can enable, for example, the UE 102 to handover between cells (e.g., from cell 124 to cell 126A or 126B) or between base stations (e.g., from the base station 104 to the base station 106A or 106B) before the UE 102 experiences a radio link failure. Additionally, the overlap can enable the UE 102 to operate in dual connectivity (DC) with the RAN 105. For example, the UE 102 can communicate with the base station 104 (acting as a master node (MN)) and the base station 106A (acting as a secondary node (SN)) in DC, and upon completing a handover to the base station 106B, can communicate with the base station 106B (acting as an MN). As another example, the UE 102 can communicate with the base station 104 (acting as an MN) and the base station 106A (acting as an SN) in DC, and upon completing an SN change, can communicate with the base station 104 (acting as an MN) and the base station 106B (acting as an SN).

[0020] More specifically, when the UE 102 is in DC with the base station 104 and the base station 106A, the base station 104 operates as a master eNB (MeNB), a master ng-eNB (Mng-eNB), or a master gNB (MgNB), and the base station 106A operates as a secondary gNB (SgNB) or a secondary ng-eNB (Sng-eNB).

[0021] In non-MBS (i.e., unicast) operation, the UE 102 may use radio bearers (e.g., DRBs or SRBs) that terminate at the MN (e.g., base station 104) or SN (e.g., base station 106A) at different times. For example, after a handover or SN change to base station 106B, the UE 102 may use radio bearers (e.g., DRBs or SRBs) that terminate at the base station 106B at different times. The UE 102 may apply one or more security keys when communicating on radio bearers in the uplink (UL) direction (i.e., from the UE 102 to the base station) and the downlink (DL) direction (i.e., from the base station to the UE 102). In non-MBS operation, the UE 102 transmits data to a base station via a radio bearer on (i.e., within) the cell's uplink BWP and / or receives data from a base station via a radio bearer on the cell's DL BWP. The UL BWP may be an initial UL BWP or a dedicated UL BWP, and the DL BWP may be an initial DL BWP or a dedicated DL BWP. The UE 102 may receive paging, system information, public alert messages, or random access responses over the DL BWP. In such non-MBS operation, the UE 102 may be in a connected state. Alternatively, if the UE 102 supports small data communication in an idle or inactive state, the UE 102 may be in an idle or inactive state.

[0022] In MBS operation, the UE 102 may use a radio bearer (e.g., a DRB or an MRB) that terminates at the MN (e.g., base station 104) or the SN (e.g., base station 106A) at different times. For example, after a handover or SN change to base station 106B, the UE 120 may use a radio bearer (e.g., a DRB or an MRB) that terminates at the base station 106B, which may be the MN or the SN, at different times. The base station may utilize the radio bearer to transmit application-level messages, such as security keys, to the UE 102. In some implementations, the base station (e.g., the MN or the SN) may transmit MBS data (e.g., via a DRB or an MRB) to the UE 102 over dedicated radio resources (i.e., radio resources dedicated to the UE 102). In such implementations, the base station may apply one or more security keys to protect the integrity of the MBS data and / or to encrypt the MBS data and transmit the encrypted and / or integrity-protected MBS data to the UE 102 over the dedicated radio resources. Correspondingly, in the downlink (from base station to UE 102) direction, upon receiving the MBS data on the radio bearer, the UE 102 can apply one or more security keys to decode the MBS data and / or check the integrity of the MBS data. In other implementations, the base station (e.g., MN or SN) can transmit the MBS data over common radio resources (i.e., radio resources common to the UE 102 and other UEs, such as common frequency resources (CFRs)) or over a cell's DL BWP from the base station to the UE 102 (e.g., over a DRM or MRB). The DL BWP can be an initial DL BWP, a dedicated DL BWP, or an MBS DL BWP (i.e., a DL BWP specific to MBS or non-unicast). In such implementations, the base station can refrain from applying security keys to the MBS data and transmit the MBS data over the radio bearer.Correspondingly, the UE 102 can omit applying a security key to the MBS data received on the radio bearer. The UE 102 can apply an application-level security key received from the CN 110 or an MBS server to the MBS data received on the radio bearer.

[0023] The base station 104 includes processing hardware 130, which may include one or more general-purpose processors (e.g., central processing units (CPUs)) and computer-readable memory that stores machine-readable instructions executable on one or more general-purpose processors and / or special-purpose processing units. The processing hardware 130 in the example implementation in FIG. 1A includes a base station MBS controller 132 configured to manage or control transmission of MBS information received from the CN 110 or edge server. For example, the base station MBS controller 132 may be configured to support radio resource control (RRC) configurations, procedures and messaging related to MBS procedures, and / or support necessary operations, as discussed below. The processing hardware 130 may include a base station non-MBS controller 134 configured to manage or control one or more RRC configurations and / or RRC procedures when the base station 104 operates as an MN or SN during non-MBS operation.

[0024] The base station 106A includes processing hardware 140, which may include one or more general-purpose processors (e.g., CPUs) and computer-readable memory that stores machine-readable instructions executable on the general-purpose processors and / or dedicated processing units. The processing hardware 140 in the example implementation of FIG. 1A includes a base station MBS controller 142 configured to manage or control transmission of MBS information received from the CN 110 or edge server. For example, the base station MBS controller 142 may be configured to support RRC configuration, procedures and messaging related to MBS procedures, and / or support necessary operations, as discussed below. The processing hardware 140 may include a base station non-MBS controller 144 configured to manage or control one or more RRC configurations and / or RRC procedures when the base station 106A operates as an MN or SN during non-MBS operation. Although not shown in FIG. 1A, the base station 106B may include processing hardware similar to the processing hardware 130 of the base station 104 or the processing hardware 140 of the base station 106A.

[0025] The UE 102 includes processing hardware 150, which may include one or more general-purpose processors (e.g., CPUs) and computer-readable memory that stores machine-readable instructions executable on the general-purpose processors and / or dedicated processing units. The processing hardware 150 in the example implementation of FIG. 1A includes a UE MBS controller 152 configured to manage or control reception of MBS information. For example, the UE MBS controller 152 may be configured to support RRC configuration, procedures and messaging related to MBS procedures, and / or support necessary operations, as discussed below. The processing hardware 150 may include a UE non-MBS controller 154 configured to manage or control one or more RRC configurations and / or RRC procedures according to any of the implementations discussed below when the UE 102 communicates with the MN and / or SN during non-MBS operation.

[0026] The CN 110 may be an Evolved Packet Core (EPC) 111 or a 5th Generation Core (5GC) 160, both of which are shown in FIG. 1A. The base station 104 may be an eNB supporting an SI interface for communicating with the EPC 111, an ng-eNB supporting an NG interface for communicating with the 5GC 160, or a gNB supporting an NR air interface and an NG interface for communicating with the 5GC 160. The base station 106A may be a EUTRA-NR DC (EN-DC) gNB (en-gNB) with an S1 interface to the EPC 111, an en-gNB that does not connect to the EPC 111, a gNB supporting an NR air interface and an NG interface to the 5GC 160, or an ng-eNB supporting a EUTRA air interface and an NG interface to the 5GC 160. The base stations 104, 106A, and 106B may support an X2 or Xn interface to directly exchange messages with each other during the scenarios discussed below.

[0027] Among other components, the EPC 111 may include a Serving Gateway (SGW) 112, a Mobility Management Entity (MME) 114, and a Packet Data Network Gateway (PGW) 116. The SGW 112 is generally configured to forward user plane packets related to audio calls, video calls, Internet traffic, etc., and the MME 114 is configured to manage authentication, registration, paging, and other related functions. The PGW 116 provides connectivity from the UE to one or more external packet data networks, e.g., an Internet network and / or an Internet Protocol (IP) Multimedia Subsystem (IMS) network. The 5GC 160 includes a User Plane Function (UPF) 162, an Access and Mobility Management (AMF) 164, and / or a Session Management Function (SMF) 166. The UPF 162 is generally configured to forward user plane packets related to audio calls, video calls, Internet traffic, etc., the AMF 164 is configured to manage authentication, registration, paging, and other related functions, and the SMF 166 is configured to manage PDU sessions. The UPF 162, the AMF 164, and / or the SMF 166 may be configured to support MBS. For example, the SMF 166 may be configured to manage or control MBS forwarding, configure the UPF 162 and / or the RAN 105 for MBS flows, and / or manage or configure MBS or PDU sessions for MBS for the UE 102. The UPF 162 is configured to forward MBS data packets, such as audio, video, and Internet traffic, to the RAN 105.The UPF 162 and / or SMF 166 may be configured for both unicast services and MBS, or for MBS only.

[0028] In general, the wireless communication network 100 may include any suitable number of base stations supporting NR and / or EUTRA cells. More particularly, the EPC 111 or 5GC 160 may be connected to any suitable number of base stations supporting NR and / or EUTRA cells. While the following examples refer specifically to particular CN types (EPC, 5GC) and RAT types (5G NR and EUTRA), in general, the techniques of this disclosure may also be applied to other suitable radio access and / or core network technologies, such as, for example, sixth-generation (6G) radio access and / or 6G core networks, or 5G NR-6G DC.

[0029] In different configurations or scenarios of the wireless communication system 100, the base station 104 can operate as an MeNB, Mng-eNB, or MgNB, the base station 106B can operate as an MeNB, Mng-eNB, MgNB, SgNB, or Sng-eNB, and the base station 106A can operate as an SgNB or Sng-eNB. The UE 102 can communicate with the base station 104 and the base station 106A or 106B via the same radio communication technology (RAT), such as EUTRA or NR, or via a different RAT.

[0030] If the base station 104 is an MeNB and the base station 106A is an SgNB, the UE 102 may be in EN-DC with the MeNB 104 and the SgNB 106A. If the base station 104 is an Mng-eNB and the base station 106A is an SgNB, the UE 102 may be in Next Generation (NG) EUTRA-NR DC (NGEN-DC) with the Mng-eNB 104 and the SgNB 106A. If the base station 104 is an MgNB and the base station 106A is an SgNB, the UE 102 may be in NR-NR DC (NR-DC) with the MgNB 104 and the SgNB 106A. If the base station 104 is an MgNB and the base station 106A is an Sng-eNB, the UE 102 may be in NR-EUTRA DC (NE-DC) with the MgNB 104 and the Sng-eNB 106A.

[0031] 1B illustrates an exemplary distributed implementation of any one or more of the base stations 104, 106A, 106B. In this implementation, the base station 104, 106A, or 106B includes a central unit (CU) 172 and one or more distributed units (DUs) 174. The CU 172 includes processing hardware, such as one or more general-purpose processors (e.g., CPUs), and computer-readable memory that stores machine-readable instructions executable on the general-purpose processors and / or dedicated processing units. For example, the CU 172 may include the processing hardware 130 or 140 of FIG. 1A.

[0032] Each of the DUs 174 also includes processing hardware, which may include one or more general-purpose processors (CPUs), and computer-readable memory that stores machine-readable instructions executable on the one or more general-purpose processors and / or special-purpose processing units. For example, the processing hardware may include a medium access control (MAC) controller configured to manage or control one or more MAC operations or procedures (e.g., random access procedures) and a radio link control (RLC) controller configured to manage or control one or more RLC operations or procedures when the base station (e.g., base station 106A) operates as an MN or SN. The processing hardware may also include a physical layer controller configured to manage or control one or more physical layer operations or procedures.

[0033] In some implementations, the CU 172 may include a logical node CU-CP 172A that hosts a control plane portion of the Packet Data Convergence Protocol (PDCP) protocol and / or the Radio Resource Control (RRC) protocol for the CU 172. The CU 172 may also include a logical node CU-UP 172B that hosts a user plane portion of the PDCP protocol and / or the Service Data Adaptation Protocol (SDAP) protocol for the CU 172. As described herein, the CU-CP 172A may transmit non-MBS control information and MBS control information, and the CU-UP 172B may transmit non-MBS data packets and MBS data packets.

[0034] The CU-CP 172A may be connected to multiple CU-UPs 172B via an E1 interface. The CU-CP 172A selects an appropriate CU-UP 172B for a service requested for the UE 102. In some implementations, a single CU-UP 172B may be connected to multiple CU-CPs 172A via an E1 interface. The CU-CP 172A may be connected to one or more DUs 174 via an F1-C interface. The CU-UP 172B may be connected to one or more DUs 174 via an F1-U interface under the control of the same CU-CP 172A. In some implementations, one DU 174 may be connected to multiple CU-UPs 172B under the control of the same CU-CP 172A. In such implementations, connectivity between the CU-UP 172B and the DU 174 is established by the CU-CP 172A using a bearer context management function.

[0035] FIG. 2 illustrates a simplified example protocol stack 200 by which a UE 102 may communicate with an eNB / ng-eNB or gNB (e.g., one or more of base stations 104, 106A, 106B).

[0036] In the example stack 200, a EUTRA physical layer (PHY) 202A provides transport channels to a EUTRA MAC sublayer 204A, which in turn provides logical channels to a EUTRA RLC sublayer 206A. The EUTRA RLC sublayer 206A then provides RLC channels to a EUTRA PDCP sublayer 208 and possibly an NR PDCP sublayer 210. Similarly, a NR PHY 202B provides transport channels to an NR MAC sublayer 204B, which in turn provides logical channels to an NR RLC sublayer 206B. The NR RLC sublayer 206B then provides RLC channels to the NR PDCP sublayer 210. In some implementations, a UE 102 supports both EUTRA and NR stacks, as shown in FIG. 2, to support handover between EUTRA and NR base stations and / or to support DC over EUTRA and NR interfaces. Additionally, as shown in FIG. 2, the UE 102 can support layering of the NR PDCP 210 over the EUTRA RLC 206A and layering of the SDAP sublayer 212 over the NR PDCP sublayer 210.

[0037] The EUTRA PDCP sublayer 208 and the NR PDCP sublayer 210 receive packets that may be referred to as service data units (SDUs) (e.g., from an Internet Protocol (IP) layer layered directly or indirectly on the PDCP layer 208 or 210) and output packets that may be referred to as protocol data units (PDUs) (e.g., to the RLC layer 206A or 206B). Except where the distinction between SDUs and PDUs is relevant, this disclosure refers to both SDUs and PDUs as "packets" for simplicity. Packets may be MBS packets or non-MBS packets. For example, MBS packets include MBS data packets containing application content for MBS services (e.g., IPv4 / IPv6 multicast distribution, IPTV, wireless software distribution, group communication, IoT applications, V2X applications, and / or emergency messages related to public safety). In another example, MBS packets include application control information for MBS services.

[0038] On the control plane, the EUTRA PDCP sublayer 208 and the NR PDCP sublayer 210 can provide SRBs to exchange, for example, RRC messages or non-access stratum (NAS) messages. On the user plane, the EUTRA PDCP sublayer 208 and the NR PDCP sublayer 210 can provide DRBs to support data exchange. The data exchanged on the NR PDCP sublayer 210 can be SDAP PDUs, Internet Protocol (IP) packets, or Ethernet packets.

[0039] In a scenario in which the UE 102 operates in an EN-DC with the base station 104 acting as an MeNB and the base station 106A acting as an SgNB, the wireless communication system 100 can provide the UE 102 with an MN-terminated bearer using the EUTRA PDCP sublayer 208 or an MN-terminated bearer using the NR PDCP sublayer 210. In various scenarios, the wireless communication system 100 can also provide the UE 102 with an SN-terminated bearer using only the NR PDCP sublayer 210. The MN-terminated bearer can be an MCG bearer, a split bearer, or an MN-terminated SCG bearer. The SN-terminated bearer can be an SCG bearer, a split bearer, or an SN-terminated MCG bearer. The MN-terminated bearer can be an SRB (e.g., SRB1 or SRB2) or a DRB. The SN-terminated bearer can be an SRB or a DRB.

[0040] In some implementations, a base station (e.g., base station 104, 106A, or 106B) broadcasts MBS data packets over one or more MBS radio bearers (MRBs), and the UE 102 then receives the MBS data packets over the MRBs. The base station may include a configuration for the MRBs in multicast configuration parameters (sometimes referred to as MBS configuration parameters), described below. In some implementations, the base station broadcasts the MBS data packets over the RLC sublayer 206, the MAC sublayer 204, and the PHY sublayer 202, and correspondingly, the UE 102 uses the PHY sublayer 202, the MAC sublayer 204, and the RLC sublayer 206 to receive the MBS data packets. In such implementations, the base station and the UE 102 may not use the PDCP sublayer 208 and the SDAP sublayer 212 to communicate the MBS data packets. In other implementations, the base station transmits MBS data packets via the PDCP sublayer 208, the RLC sublayer 206, the MAC sublayer 204, and the PHY sublayer 202, and correspondingly, the UE 102 uses the PHY sublayer 202, the MAC sublayer 204, the RLC sublayer 206, and the PDCP sublayer 208 to receive the MBS data packets. In such implementations, the base station and the UE 102 may not use the SDAP sublayer 212 to communicate the MBS data packets. In yet another implementation, the base station transmits MBS data packets via the SDAP sublayer 212, the PDCP sublayer 208, the RLC sublayer 206, the MAC sublayer 204, and the PHY sublayer 202, and correspondingly, the UE 102 uses the PHY sublayer 202, the MAC sublayer 204, the RLC sublayer 206, the PDCP sublayer 208, and the SDAP sublayer 212 to receive the MBS data packets.

[0041] To simplify the following description, UE 102 represents UE 102A and UE 102B unless explicitly stated otherwise.

[0042] 3A-9 are messaging diagrams of example scenarios in which one or more UEs and base stations of a RAN implement the techniques of the present disclosure for managing MBS over SPS. Generally speaking, events in FIGS. 3A-9 that are similar are labeled with similar reference numbers, and similarities are discussed as appropriate. Except for differences shown in the figures and discussed below, any of the alternative implementations discussed with respect to particular events (e.g., messaging and processing) may also be applied to events labeled with similar reference numbers in other figures.

[0043] 3A , the base station 104 initially transmits (i.e., multicasts or broadcasts) 302 an MBS SPS configuration (i.e., an SPS configuration for an MBS) to the UEs 102A and 102B. In some implementations, the base station 104 may broadcast 302 a system information block (SIB) containing the MBS SPS configuration via the cell 124. In other implementations, the base station 104 may broadcast 302 an MBS-specific message containing the MBS SPS configuration via the cell 124. For example, the MBS-specific message may be a Multimedia Broadcast Multicast Service (MBMS) point-to-multipoint control channel (MCCH) message. In some implementations, a UE 102 (i.e., UE 102A and / or UE 102B) operating in an idle or inactive state (e.g., RRC_IDLE state, RRC_INACTIVE state) receives 302 the MBS SPS configuration from the base station 104. Alternatively, a UE 102 operating in a connected state (e.g., RRC_CONNECTED state) receives 302 the MBS SPS configuration from the base station 104.

[0044] In an MBS SPS configuration, the base station 104 can include, for example, a periodicity (e.g., T) at which the SPS radio resources occur. In an MBS SPS configuration, the base station 104 can also include a physical uplink control channel (PUCCH) configuration that configures radio resources for the UE 102 to transmit hybrid automatic repeat request (HARQ) acknowledgments (ACKs) or HARQ negative acknowledgments (NACKs). In an MBS SPS configuration, the base station 104 can additionally include a physical downlink shared channel (PDSCH) configuration that includes configuration parameters for receiving PDSCH transmissions containing MBS data on the SPS resources.

[0045] After transmitting 302 the MBS SPS configuration, the base station 104 transmits one or more MBS SPS activation commands to the UE 102 to enable the UE 102 to start receiving MBS data packets. In some implementations, the MBS SPS activation command may be a DCI. More specifically, in slot x, the base station 104 may transmit 304 a first MBS SPS activation command (e.g., including a time offset=k) to the UE 102 to enable (activate) the UE 102 to start receiving a PDSCH transmission including MBS data on SPS resources in slot x+k. The time offset refers to the number of slots over which the base station 104 transmits MBS data after the base station 104 transmits the MBS SPS activation command. The base station 104 may send the first MBS SPS activation command by unicasting the first MBS SPS activation command to each of the UEs 102A and 102B individually or by broadcasting or multicasting the first MBS SPS activation command to both the UEs 102A and 102B (304).

[0046] In some implementations, the base station 104 can send one or more additional MBS activation commands to ensure that the UE 102 is enabled (i.e., activated) to start receiving MBS data on the SPS resource in event 312. For example, the base station 104 can send a second MBS activation command (e.g., including a time offset = k - i) in slot x + i (i < k) (306) to enable the UE 102 to start receiving MBS data on the SPS resource in event 312, and / or can send a Pth MBS activation command (e.g., time offset = k - j) in slot x + j (i < j < k) (308). The value “P” can be an integer greater than 2. Other than the time offset, the second MBS SPS activation command can be the same as the first MBS SPS activation command. In other words, the second MBS SPS activation command can be a retransmission or rebroadcast of the first MBS SPS activation command, in which case the time offset of the second MBS SPS activation command is shifted relative to the time offset of the first MBS SPS activation command such that both the first MBS SPS activation command and the second MBS SPS activation command point to the same slot (slot x + k) at which the base station 104 starts transmitting MBS data. Similarly, the Pth MBS activation command can be a retransmission or rebroadcast of the first MBS SPS activation command, in which case the time offset of the Pth MBS activation command is shifted relative to the time offset of the first SPS activation command such that both the first MBS SPS activation command and the Pth activation command point to slot x + k.

[0047] After transmitting the MBS SPS activation command, the base station 104 transmits a PDSCH transmission including MBS data on the SPS resources in slot x+k (312), transmits a PDSCH transmission including MBS data on the SPS resources in slot x+k+T (314), transmits a PDSCH transmission including MBS data on the SPS resources in slot x+k+2T (316), ..., transmits a PDSCH transmission including MBS data on the SPS resources in slot x+k+mT (318). The value "m" may be an integer greater than 2. The base station 104 can configure SPS resources in the MBS SPS activation command and / or the MBS SPS configuration. In some implementations, the SPS resources include frequency resources such as physical resource blocks (PRBs). For example, the base station 104 can include a frequency domain resource allocation field in the MBS SPS activation command or the MBS SPS configuration to configure PRBs. The base station 104 can include a time-domain resource allocation field in the MBS SPS activation command or MBS SPS configuration to configure a time offset. The base station 104 can also include configuration parameters for a modulation and coding scheme (MCS), a new data indicator (e.g., a value of 0), an SPS index associated with the MBS SPS configuration, a redundancy version, a PUCCH resource indicator, a transmit power control (TPC) command (e.g., for a scheduled PUCCH), a virtual resource block (VRB) to PRB mapping, an indicator for a DCI format, and / or a PDSCH to HARQ feedback timing indicator.

[0048] After the UE 102 receives one of the MBS SPS activation commands (e.g., the first, second, and / or third MBS SPS activation commands), the UE 102 begins receiving a PDSCH transmission including MBS data on the SPS resources in slot x+k (312). The UE 102 then receives a PDSCH transmission including MBS data on the SPS resources in slot x+k+T (314), receives a PDSCH transmission including MBS data on the SPS resources in slot x+k+2T (316), ..., receives a PDSCH transmission including MBS data on the SPS resources in slot x+k+mT (318).

[0049] Events 304, 306, and 308 are collectively referred to in this disclosure as MBS SPS activation procedure 380, events 312, 314, 316, and 318 are collectively referred to in this disclosure as MBS SPS data transmission procedure 382, ​​and MBS activation procedure 380 and MBS SPS data transmission procedure 382 are collectively referred to as MBS SPS activation and transmission procedure 383.

[0050] Later, the base station 104 can perform an MBS SPS deactivation procedure (384) to deactivate the SPS resources. In the MBS SPS deactivation procedure, the base station 104 can send one or more MBS SPS deactivation commands (i.e., SPS deactivation commands for MBSs) to the UE 102 (320, 322, 324) to ensure that the UE 102 receives one of the SPS deactivation commands. In some implementations, the base station 104 can determine to perform the MBS SPS deactivation procedure (384) if the number of UEs (i.e., UE 102A, UE 102B, and / or other UEs) to which the base station is transmitting MBS data is below a predetermined threshold. Otherwise, the base station 104 can refrain from performing the MBS SPS deactivation procedure.

[0051] In response to or after receiving one of the SPS deactivation commands, the UE 102 deactivates the SPS resources. After deactivating the SPS resources, the UE 102 stops attempting to receive PDSCH transmissions on the SPS resources. After performing the MBS SPS deactivation procedure (384), the base station 104 may transmit DCI to schedule a PDSCH transmission including MBS data to the UE 102. More specifically, the base station 104 may unicast a specific DCI to schedule a specific PDSCH transmission including MBS data to the UE 102. The UE 102 may receive the specific DCI and attempt to receive a specific PDSCH transmission according to the specific DCI. The UE 102 decodes the PDSCH transmission to obtain the unicast MBS data.

[0052] In some implementations, the base station 104 may include an inactivity counter value (e.g., X) in the MBS SPS configuration. If the UE 102 detects X consecutive missing PDSCH transmissions on the SPS resource, the UE 102 may autonomously deactivate the SPS resource. In other implementations, the base station 104 may include an inactivity timer value (e.g., X) in the MBS SPS configuration. If the UE 102 detects X consecutive missing PDSCH transmissions on the SPS resource within the inactivity timer value, the UE 102 may autonomously deactivate the SPS resource. In such a case, the base station 104 may not perform an MBS SPS deactivation procedure. In some implementations, the UE 102 may detect missing PDSCH transmissions on the SPS resource if the energy detected on the SPS resource is below a threshold. In one implementation, the base station 104 may configure the value of the threshold in the MBS SPS configuration. In another implementation, the UE 102 can determine the value of the threshold independently from the base station 104.

[0053] In some implementations, the base station 104 can (decide to) transmit an MBS SPS configuration to the UE 102 if the UE 102 supports receiving MBS on SPS resources. Otherwise, the base station 104 does not transmit an MBS SPS configuration to the UE 102.

[0054] 3B, scenario 300B is similar to scenario 300A, except that the base station transmits a first SPS configuration to UE 102A using dedicated resources for UE 102A and a second SPS configuration to UE 102B using dedicated resources for UE 102B. Instead of broadcasting or multicasting the MBS SPS configurations to UE 102, the base station 104 unicasts the first MBS SPS configuration to UE 102A (301) and the second MBS SPS configuration to UE 102B (303). The first and second MBS SPS configurations may be the same, or at least a portion of the first and second MBS SPS configurations may be different. For example, both the first and second MBS configurations may indicate the same periodicity T for the SPS resources and may include the same PDSCH configuration, including configuration parameters for receiving PDSCH transmissions including MBS data on the SPS resources. The first and second MBS configurations may each include a different PUSCH configuration that configures different radio resources for UE 102A and UE 102B to use to transmit HARQ ACKs or NACKs. Events 301 and 303 are collectively referred to in this disclosure as an MBS configuration procedure 305.

[0055] After the MBS configuration procedure 305, the base station 104 performs an MBS SPS activation and data transmission procedure to transmit MBS data to the UEs 102A and 102B (383). In some implementations, the base station 104 also performs an MBS deactivation procedure to instruct the UEs 102A and 102B to stop receiving MBS data on the SPS resources (384).

[0056] 4, scenario 400 is similar to scenario 300A, except that the base station periodically rebroadcasts the SPS activation command based on the SPS periodicity T. First, the base station 104 performs an MBS SPS configuration procedure (e.g., event 302 or 305) to send an MBS SPS configuration to the UE 102A and the UE 102B (402). Then, the base station 104 sends (i.e., multicast, broadcast, or unicast) a first activation command to the UE 102 including a time offset=k in slot x to activate the UE 102 to receive MBS data on SPS resources in slot x+k (404).

[0057] After transmitting the first SPS activation command (404), the base station 104 transmits a PDSCH transmission including MBS data on the SPS resource in slot x + k (410). In some implementations, the base station 104 transmits one or more additional MBS activation commands to ensure that the UE 102 is activated to start receiving MBS data on the SPS resource. In particular, the base station 104 can transmit an SPS activation command once per period. Thus, when n < T, in slot x + k + n, the base station 104 can transmit a second SPS activation command (e.g., including a time offset = T - n) (407) in the period after transmitting the MBS data (410). Then, the base station 104 can transmit MBS data on the SPS resource in slot x + k + T. The base station can also, when p < 2T, transmit a third SPS activation command (e.g., including a time offset 2T - p) in slot x + k + p (409). Then, the base station 104 transmits MBS data on the SPS resource in slot x + k + 2T (414). In slot x + k + q, the base station 104 transmits the (m + 1)-th SPS activation command (e.g., including a time offset = mT - q), where q < mT (411). The base station 104 transmits MBS data on the SPS resource in slot x + k + mT (416). The base station 104 can continue to transmit SPS activation commands and MBS data in each period of the SPS resource. Events 404, 410, 407, 412, 409, 414, 411, and 416 are collectively referred to in this disclosure as the MBS SPS activation and data transmission procedure 483. Later, the base station 104 can perform an MBS SPS deactivation procedure similar to the MBS deactivation procedure 384 (484). FIG. 4 shows each pair of activation commands and MBS data that are completed before the transmission of the next activation command, and the pairs can overlap when n is shorter than k.

[0058] [[ID=३]] 5, in scenario 500, base station 104 transmits an MBS SPS configuration and an activation indication to UE 102A and UE 102B in separate RRC messages. First, base station 104 transmits (i.e., unicasts) to UE 102A an RRC reconfiguration message (e.g., an RRCConnectionReconfiguration message or an RRCReconfiguration message) including a first MBS SPS configuration and an instruction to activate receiving MBS data according to the first MBS SPS configuration (i.e., an activation indication). In some implementations, the activation indication is included within the first MBS SPS configuration. In such implementations, the activation indication may be an information element (IE), a field, or a flag. Alternatively, in such implementations, the activation indication may not be an explicit indication. Rather, receipt of the first MBS SPS configuration (i.e., an SPS configuration for receiving MBS data) implicitly instructs UE 102A to activate receiving MBS data according to the first MBS SPS configuration. In response to receiving the RRC reconfiguration message (501), UE 102A sends an RRC reconfiguration complete message (e.g., an RRCConnectionReconfigurationComplete message or an RRCReconfigurationComplete message) to base station 104 (502).

[0059] The base station 104 also sends an RRC reconfiguration message to the UE 102B that includes the second MBS SPS configuration and instructions to activate receiving MBS data according to the second MBS SPS configuration (503). Similar to the first and second MBS SPS configurations discussed with reference to FIG. 3B, the first and second MBS SPS configurations may be the same, or at least portions of the first and second MBS SPS configurations may be different. In response to receiving the RRC reconfiguration message (503), the UE 102B sends an RRC reconfiguration complete message to the base station 104 (504).

[0060] After UE 102A and UE 102B acknowledge receipt of the RRC reconfiguration message, base station 104 performs an MBS SPS data transmission procedure similar to MBS SPS data transmission procedure 382 (582).

[0061] Later, the base station 104 may instruct the UEs 102A and 102B to stop receiving MBS data according to the MBS SPS configuration. The base station 104A sends an RRC reconfiguration message including an MBS SPS release indication to the UEs 102A (506) and 102B (508). In response, the UEs 102A and 102B stop receiving MBS data according to the first and second MBS SPS configurations, respectively. The UE 102A sends an RRC reconfiguration complete message to the base station 104 (510), and similarly, the UE 102B sends an RRC reconfiguration complete message to the base station 104 (512).

[0062] 6A-7 illustrate feedback mechanisms that the base station 104 and the UE 102 can utilize for MBS over SPS. Referring first to FIG. 6A, the base station 104 receives a hybrid automatic repeat request (HARQ) acknowledgment (ACK) from the UE 102 (i.e., the UE 102A or the UE 102B) in response to an MBS SPS activation command. Initially, the base station 104 transmits (i.e., multicast, broadcast, or unicast) an MBS SPS configuration to the UE 102 (602). Later, the base station transmits (i.e., multicast, broadcast, or unicast) a first MBS SPS activation command to the UE 102 to activate the UE 102 to receive MBS data according to the MBS SPS configuration (604). If the UE 102 successfully receives the first MBS SPS activation command, the UE 102 transmits a HARQ ACK to the base station 104 (626). The UE 102 may use resources indicated in the MBS SPS configuration or the first MBS SPS activation command to transmit the HARQ ACK (626). For example, the base station 104 may transmit at least one of the MBS SPS configuration or the first MBS SPS activation command to the UE 102 via unicast transmission. Thus, the at least one of the MBS SPS configuration or the first MBS SPS activation command may indicate particular resources on which the UE 102 may transmit the HARQ ACK for the first MBS SPS activation command (626).

[0063] If the base station 104 does not receive 626 a HARQ ACK, the base station 104 may send 606 a second MBS SPS activation command to the UE 102, which may be identical to the first MBS SPS activation command except for a time offset. The base station 104 may continue to retransmit the MBS SPS activation command to the UE 102 until the base station 104 receives a HARQ ACK from the UE 102 or until SPS resources occur on which the base station 104 transmits MBS data. Events 604, 626, and 606 are collectively referred to in this disclosure as an MBS SPS activation procedure 680.

[0064] The base station 104 may then perform 682 an MBS data packet transmission procedure similar to the MBS data packet transmission procedure 382 to transmit MBS data to the UE 102 on SPS resources. Later, the base station 104 may instruct the UE 102 to stop receiving MBS data by sending 620 a first SPS deactivation command to the UE 102. When the UE 102 receives 620 the first MBS SPS deactivation command, the UE 102 sends 628 a HARQ ACK to the base station 104. Similar to the HARQ ACK that the UE 102 sends 626, the UE 102 may use the resources indicated in the MBS SPS configuration or the first MBS SPS activation command to send 628 the HARQ ACK. In some implementations, the UE 102 may use resources indicated in at least one of the first MBS SPS deactivation command or the MBS SPS configuration to transmit 628 a HARQ ACK. If the base station 104 does not receive 628 a HARQ ACK, the base station 104 may transmit 622 a second MBS SPS deactivation command to the UE 102 to ensure that the UE 102 receives the MBS SPS deactivation command. The base station 104 may continue to transmit MBS deactivation commands to the UE 102 until the base station 104 receives the HARQ ACK. Events 620, 628, and 622 are collectively referred to in this disclosure as an MBS SPS deactivation procedure 684.

[0065] 6B illustrates a scenario 600B that is generally similar to scenario 600A, except that the UE 102 transmits an ACK for the MBS SPS activation command in a MAC PDU. In particular, after successfully receiving 604 the first MBS activation command, the UE 102 transmits 627 a MAC PDU including an ACK for the first MBS SPS activation command. To transmit 627 the ACK, the UE 102 can use resources indicated in the MBS SPS configuration or the first MBS SPS activation command, or can use uplink resources configured in the UE 102 to transmit user data to the base station 104. For example, the UE 102 can receive a first DCI from the base station 104 to allocate uplink resources. In another example, the UE 102 performs a first random access procedure with the base station 104 and receives a first random access response of the first random access procedure that includes an uplink grant allocating uplink resources. Similarly, after successfully receiving 620 the first MBS SPS deactivation command, the UE 102 transmits 629 a MAC PDU including an ACK for the first MBS deactivation command. To transmit 629 the ACK, the UE 102 can use the MBS SPS configuration, the first MBS SPS activation command, the resources indicated in the first MBS SPS deactivation command, or uplink resources configured in the UE 102 to transmit user data to the base station 104. For example, the UE 102 can receive a second DCI from the base station 104 to allocate uplink resources. In another example, the UE 102 performs a second random access procedure with the base station 104 and receives a second random access response of the second random access procedure including an uplink grant allocating uplink resources. Events 604, 627, and 606 are collectively referred to in this disclosure as an MBS SPS activation procedure 681, and events 620, 629, and 622 are collectively referred to in this disclosure as an MBS SPS deactivation procedure 685.

[0066] 7, scenario 700 is generally similar to scenario 600A, except that the UE 102 transmits a HARQ ACK or NACK to the base station 104 in response to receiving MBS data rather than an MBS activation command. The base station 104 transmits an MBS SPS configuration (702) and a first MBS SPS activation command to the UE 102 (704). The base station 104 then transmits an MBS data packet to the UE 102 on SPS resources (710). If the UE 102 successfully receives the MBS data packet (710), the UE 102 transmits a HARQ ACK (i.e., a positive acknowledgment) to the base station 104 (730). Otherwise, the UE 102 transmits a HARQ NACK (i.e., a negative acknowledgment) to the base station 104 (730). Similar to the HARQ ACK that the UE 102 transmits (626), the UE 102 can use the resources indicated in the MBS SPS configuration or the first MBS SPS activation command to transmit (730) the HARQ ACK / NACK. If the base station 104 does not receive (730) the HARQ ACK / NACK, the base station 104 determines that the UE 102 did not successfully receive the first MBS SPS activation command. In response, the base station transmits (706) a second MBS SPS activation command to the UE 102, which may be identical to the first MBS SPS activation command except for a time offset. The base station 104 then performs (782) an MBS data packet transmission procedure and (784) an MBS SPS deactivation procedure, similar to procedures 682 and 684, respectively.

[0067] 8-9 illustrate a scenario in which a base station 104 activates a UE 102A to receive both unicast and MBS data on SPS resources. Referring first to FIG. 8, the base station 104 transmits (i.e., multicast, broadcast, or unicast) an MBS SPS configuration to the UE 102A (802). The base station 104 performs an MBS SPS activation procedure (e.g., MBS SPS activation procedure 380, MBS SPS activation and data transmission procedure 483, MBS SPS activation procedure 680, MBS SPS activation procedure 681, MBS SPS activation procedure 780) to receive MBS data on the SPS resources (880). The base station 104 may perform 882 an MBS data packet transmission procedure (e.g., MBS SPS data transmission procedure 382, ​​MBS SPS activation and data transmission procedure 483, MBS data packet transmission procedure 682, MBS data packet transmission procedure 782) to transmit SPS data on the SPS resources according to the MBS SPS configuration, where the SPS resources have a first periodicity T1. Later, the base station 104 may perform 884 an MBS SPS deactivation procedure to instruct the UE 102A to stop receiving MBS data on the SPS resources.

[0068] Before or after transmitting 802 the MBS SPS configuration to the UE 102A, the base station 104 also transmits 804 a unicast SPS configuration to the UE 102A. In slot z, the base station transmits 606 a unicast SPS activation command to the UE 102A to activate the UE 102A to receive unicast data on SPS resources according to the unicast SPS configuration. The periodicity T2 of the SPS resources (i.e., unicast SPS resources) on which the base station 104 transmits unicast data may be different from the periodicity T1 of the SPS resources (i.e., MBS SPS resources) on which the base station 104 transmits MBS data. The base station 104 may transmit the first data packet, the second data packet, the third data packet, ..., the (r+1)th data packet on the unicast SPS resources at events 808, 810, 812, and 814, respectively, in slots z+w, z+w+T2, z+w+2*T2, ..., and z+w+r*T2. To instruct the UE 102A to stop receiving unicast data on the unicast SPS resources, the base station 104 may send 816 a unicast deactivation command to the UE 102A. Although the unicast data transmission is shown in FIG. 8 as occurring after the MBS data transmission, events 810-814 may occur, for example, during the MBS data packet transmission procedure 882. Thus, the base station 104 may enable the UE 102A to receive both unicast data and MBS data on the unicast SPS resources with periodicity T2 and on the MBS SPS resources with periodicity T1, respectively.

[0069] Furthermore, the MBS SPS activation command that the base station 104 sends during the MBS SPS activation procedure 880 and the unicast SPS activation command that the base station 104 sends 806 may have different formats. For example, the MBS SPS activation command may be in an MBS-specific format, and the unicast SPS activation command that the base station sends 816 may be in a unicast-specific format. Similarly, the MBS SPS deactivation command that the base station 104 sends during the MBS SPS deactivation procedure 884 and the unicast SPS deactivation command that the base station sends 816 may have different formats (e.g., an MBS-specific format or a unicast-specific format). Thus, the UE 102A can identify whether the SPS activation command is for receiving unicast data or MBS data based on the format of the SPS activation command, as described below with reference to FIG. 13A and FIG. 15B.

[0070] Additionally or alternatively, the base station 104 may use different RNTIs to transmit the MBS SPS activation command and the unicast SPS activation command. The base station 104 may use an RNTI associated with the MBS (e.g., a group RNTI or an MBS-RNTI) to scramble the CRC value and transmit the scrambled CRC value with the MBS SPS activation command. Similarly, the base station may use an RNTI associated with a particular UE 102A (e.g., a C-RNTI) to scramble the CRC value of the unicast SPS activation command and transmit the scrambled CRC value with the unicast SPS activation command. The use of different RNTIs for the unicast activation command and the MBS activation command is further discussed with reference to Figures 12 and 15A.

[0071] 9 shows a scenario 900 that is similar to scenario 800, except that the base station 104 uses an SPS index value to indicate whether the SPS activation command is for receiving unicast data or MBS data. The base station 104 sends 902 an SPS configuration 1 to the UE 102A, configuring the UE 102A to receive data on a first SPS resource having a periodicity of T1. In slot a, the base station 104 sends 904 an SPS activation command including an SPS index having a value equal to "1." The SPS index value equal to 1 refers to SPS configuration 1 (i.e., the first SPS configuration the UE 102A receives from the base station 104). The SPS activation command may also include a time offset equal to b. Thus, the base station 104 transmits a first MBS data packet on the first SPS resource according to SPS configuration 1 in slot a+b (906), transmits a second MBS data packet on the first SPS resource in slot a+b+T1 (908), transmits a third MBS data packet on the first SPS resource in slot a+b+2*T1 (910), ..., transmits the (m+1)th MBS data packet on the first SPS resource in slot a+b+m*T1 (912). To instruct the UE 102A to stop receiving data on the first SPS resource, the base station 104 transmits an SPS deactivation command including an SPS index equal to "1" to reference SPS configuration 1 (914).

[0072] Similarly, the base station 104 also transmits SPS configuration 2 to the UE 102A, configuring the UE 102A to receive data on a second SPS resource having periodicity T2 (903). In slot c, the base station 104 transmits an SPS activation command including an SPS index having a value equal to "2" (905). The SPS index value equal to 2 refers to SPS configuration 2 (i.e., the second SPS configuration that the UE 102A receives from the base station 104). The SPS activation command may also include a time offset equal to d. Thus, the base station 104 transmits to the UE 102A a first unicast data packet on the second SPS resource according to SPS configuration 2 in slot c+d (907), a second unicast data packet on the second SPS resource in slot c+d+T2 (909), a third unicast data packet on the second SPS resource in slot c+d+2*T2 (911), ..., an (n+1)th unicast data packet on the second SPS resource in slot c+d+n*T2 (913). To instruct the UE 102A to stop receiving data on the second SPS resource, the base station 104 transmits an SPS deactivation command including an SPS index equal to "2" to refer to SPS configuration 2 (915).

[0073] In some implementations, the SPS configuration formats (eg, IE formats) of SPS Configuration 1 and SPS Configuration 2 may be the same or different.

[0074] 10A-18 are flow diagrams illustrating example methods that a base station (e.g., base station 104) of a RAN (e.g., RAN 105) or a UE (e.g., UE 102A or UE 102B) can implement to manage transmission / reception of MBS over an SPS.

[0075] 10A , a base station may implement an example method 1000A for transmitting MBS data packets to multiple UEs using SPS. In block 1002, the base station generates an SPS configuration for periodically scheduling radio resources for multicasting the MBS data packets to the multiple UEs. In block 1004, the base station transmits the SPS configuration to the multiple UEs (e.g., events 302, 305, 402, 602, 702, 802, and 902). Next, in block 1006, the base station generates SPS activation commands for enabling the multiple UEs to periodically receive the MBS data packets according to the SPS configuration, and in block 1008, transmits the SPS activation commands one or more times to the multiple UEs (e.g., events 304, 306, 308, 380, 404, 407, 409, 411, 481, 604, 606, 704, 706, 880, and 904). In block 1010, the base station periodically transmits MBS data packets to multiple UEs according to the SPS configuration (e.g., 312, 314, 316, 318, 382, ​​380, 410, 412, 414, 416, 682, 710, 782, 882, 908, 910, 912). The base station then generates SPS deactivation commands to disable the multiple UEs from periodically receiving MBS data packets according to the SPS configuration in block 1012 and transmits the SPS deactivation commands one or more times to the multiple UEs in block 1014 (e.g., blocks 320, 322, 423, 384, 484, 620, 622, 784, 884, 914).

[0076] FIG. 10B is a flow diagram of an example method 1000B similar to method 1000A, but in which a base station transmits a specific SPS configuration to each of a plurality of UEs. Blocks in FIG. 10B that are the same as blocks in FIG. 10A are labeled with the same reference numbers. In block 1003, the base station generates a specific SPS configuration for each of a plurality of UEs for periodically scheduling radio resources for multicasting MBS data packets to the plurality of UEs. In block 1005, the base station transmits the specific SPS configuration to each of the plurality of UEs (e.g., event 305). The specific SPS configurations may be the same, or at least some of the SPS configurations may be different.

[0077] 11A is a flow diagram of an example method 1100A that may be implemented by a base station for retransmitting an SPS activation command in response to not receiving an acknowledgment to the initial SPS activation command. In block 1102, the base station generates a first SPS configuration and a second SPS configuration for a first UE and a second UE, respectively, to periodically schedule radio resources for multicasting MBS data packets to the first and second UEs. In some implementations, in the first and second SPS configurations, the base station allocates first and second radio resources to the first and second UEs, respectively, for transmitting the SPS activation command and / or the acknowledgment to the MBS data. In block 1104, the base station transmits the first and second SPS configurations to the first and second UEs, respectively (e.g., events 305, 602). The base station then generates a first activation command to enable the first and second UEs to periodically receive MBS data packets according to the first and second SPS configurations, respectively, in block 1106 and transmits the first SPS activation command to the first and second UEs (e.g., event 604) in block 1108. In some implementations, the base station unicasts the first SPS activation command to each of the first and second UEs. In other implementations, the base station multicasts or broadcasts the first SPS activation command to the first and second UEs.

[0078] After transmitting the first SPS activation command in block 1110, the base station transmits first MBS data packets to the first and second UEs (e.g., event 682). In block 1112, the base station determines that the base station failed to receive an acknowledgment confirming receipt of the first activation command from the second UE (e.g., scenario 600A in which the base station 104 does not receive a HARQ ACK (626) or scenario 600B in which the base station 104 does not receive a MAC PDU (627)). In response, in block 1114, the base station generates a second activation command to enable the first and second UEs to periodically receive MBS data packets according to the first and second SPS configurations, respectively, and transmits the second activation command to the second UE in block 1116 (e.g., event 606). In some implementations, the base station unicasts the second SPS activation command to the second UE. In other implementations, the base station multicasts or broadcasts the second SPS activation command to the first and second UEs.

[0079] 11B is a flow diagram of an example method 1100B that is similar to method 1100A. However, after block 1100, the base station determines in block 1113 that the base station failed to receive an acknowledgment (positive or negative) from the second UE confirming receipt of the first MBS data packet (e.g., scenario 700 in which the base station 104 does not receive 730 a HARQ ACK / NACK). In response, the base station generates a second SPS activation command in block 1114.

[0080] 12 is a flow diagram of an example method 1200 for transmitting an SPS (de)activation command and a cyclic redundancy check (CRC) to a UE that may be implemented by a base station. In block 1202, the base station generates a (de)activation command for the UE. In block 1204, the base station generates a CRC value for the SPS (de)activation command. In block 1206, the base station determines whether the SPS (de)activation command (de)activates SPS for unicast data transmission or SPS for MBS. If the SPS (de)activation command is for unicast data transmission, in block 1208, the base station scrambles the CRC value with a first RNTI (e.g., a scheduling C-RNTI (CS-RNTI) configured for the UE) and transmits the SPS (de)activation command and the scrambled CRC value to the UE in block 1212. If the SPS (de)activation command is for an MBS, in block 1210, the base station scrambles the CRC value using a second RNTI (e.g., a group CS-RNTI or an MBS CS-RNTI), and in block 1212, transmits the SPS (de)activation command and the scrambled CRC value to the UE.

[0081] FIG. 13A is a flow diagram of an example method 1300A that may be implemented by a base station for formatting an SPS (de)activation command based on whether the SPS (de)activation command is for transmitting MBS data or unicast data. Like blocks in FIGS. 13A-13B are labeled with like reference numerals. In block 1302, the base station determines to (de)activate SPS for the UE. In block 1304, the base station determines whether the base station is (de)activating SPS for transmitting unicast data or for MBS. If the base station is (de)activating SPS for unicast data, the base station generates an SPS (de)activation command according to a first format (e.g., a unicast-specific format) in block 1306. Otherwise, the base station generates an SPS (de)activation command according to a second format (e.g., an MBS-specific format) in block 1308. In block 1310, the base station sends an SPS (de)activation command to the UE.

[0082] 13B is a flow diagram of an example method 1300B that is similar to method 1300A. However, if the base station determines to (de)activate SPS for unicast data in block 1304, the base station generates an SPS (de)activation command in block 1307 that includes an index field (e.g., an SPS index) set to a first value. If the base station determines to (de)activate SPS for MBS in block 1304, the base station generates an SPS (de)activation command in block 1309 that includes an index field set to a second value. For example, the first value may refer to an SPS configuration that configures the UE to receive unicast data on SPS resources, and the second value may refer to an SPS configuration that configures the UE to receive MBS data on SPS resources. In contrast to the SPS (de)activation commands that the base station generates in blocks 1306 and 1308, the SPS (de)activation commands that the base station generates in blocks 1307 and 1309 may have the same format.

[0083] FIG. 14 is a flow diagram of an example method 1400 for determining whether to send separate SPS configurations and SPS activation commands that may be implemented by a base station. In block 1402, the base station determines to configure SPS for the UE. In block 1404, the base station determines whether the base station configures SPS for unicast data transmission or for MBS. If the base station configures SPS for unicast data transmission, the base station transmits an SPS configuration for unicast data transmission to the UE in block 1406. Then, in block 1408, the base station transmits an SPS activation command to the UE to activate the UE to receive unicast data according to the SPS configuration. If the base station configures SPS for MBS, the base station transmits an SPS configuration for the MBS to the UE in block 1410, and receiving the configuration activates the UE to receive MBS data according to the SPS configuration.

[0084] 15A-15C and 16 show example methods that may be implemented by a UE. Like blocks in FIGS. 15A-15C are labeled with like reference numbers.

[0085] 15A is a flow diagram of an example method 1500A for determining whether an SPS activation command enables receiving unicast data or MBS data based on a CRC received with the SPS activation command. In block 1502, a UE receives an SPS activation command. In block 1504, the UE determines whether the CRC value received with the SPS activation command is scrambled using a first RNTI or a second RNTI. If the CRC value is scrambled using the first RNTI (e.g., CS-RNTI), the UE receives unicast data on the SPS resources configured by the SPS activation command in block 1506. If the CRC value is scrambled using a second RNTI (e.g., group CS-RNTI or MBS CS-RNTI), the UE receives MBS data on the SPS resources configured by the SPS activation command in block 1508.

[0086] The UE may later receive an SPS deactivation command. The UE determines whether the CRC value received with the SPS deactivation command is scrambled using the first RNTI or the second RNTI. If the CRC value is scrambled using the first RNTI, the UE deactivates SPS resources for unicast. If the CRC value is scrambled using the second RNTI, the UE deactivates SPS resources for MBS.

[0087] 15B is a flow diagram of an example method 1500B similar to method 1500A. However, the UE determines whether the SPS activation command enables receiving unicast data or MBS data based on the format of the SPS activation command. In block 1503, the UE determines whether the SPS activation command conforms to a first format or a second format. If the SPS activation command is in the first format (a unicast-specific format), the UE receives unicast data on the SPS resources configured by the SPS activation command in block 1506. If the SPS activation command is in the second format (e.g., an MBS-specific format), the UE receives MBS data on the SPS resources configured by the SPS activation command in block 1508.

[0088] Later, the UE may receive an SPS deactivation command. The UE determines whether the SPS deactivation command conforms to a third format or a fourth format. If the SPS deactivation command is in the third format (e.g., a format specific to unicast), the UE deactivates SPS resources for unicast. If the SPS deactivation command is in the fourth format (e.g., a format specific to MBS), the UE deactivates SPS resources for MBS. In some implementations, the first and third formats may be the same or different, and the second and fourth formats may be the same or different.

[0089] 15C is a flow diagram of an example method 1500C similar to method 1500A. However, the UE determines whether the SPS activation command enables receiving unicast data or MBS data based on field values ​​in the SPS activation command. In block 1507, the UE determines whether the SPS activation command includes an SPS index field having a first value or an SPS index field having a second value. If the SPS index field is equal to the first value, the UE receives unicast data on the SPS resources configured by the SPS activation command in block 1506. If the SPS index field is equal to the second value, the UE receives MBS data on the SPS resources configured by the SPS activation command in block 1508.

[0090] The UE may subsequently receive an SPS deactivation command. The UE determines whether the SPS deactivation command includes an SPS index field having a first value or an SPS index field having a second value. If the SPS index field is equal to the first value, the UE deactivates SPS resources for unicast. If the SPS index field is equal to the second value, the UE deactivates SPS resources for MBS.

[0091] FIG. 16 is a flow diagram of an example method 1600 for determining whether to activate receiving data according to an SPS configuration based on whether the SPS configuration is for unicast or MBS. In block 1602, a UE receives an SPS configuration. In block 1604, the UE determines whether the SPS configuration is for receiving unicast data or for receiving MBS. If the SPS configuration is for receiving unicast data, in block 1606, the UE refrains from activating receiving unicast data according to the SPS configuration until the UE receives an SPS activation command for unicast. If the SPS configuration is for receiving MBS, in block 1608, the UE activates receiving MBS according to the SPS configuration. The UE activates receiving MBS based on receiving the SPS configuration and does not need to receive a separate SPS activation command to activate receiving MBS.

[0092] 17 is a flow diagram of an example method 1700 for managing transmission of MBS using SPS, which may be implemented by a base station. In block 1702, the base station transmits a configuration (e.g., an MBS SPS configuration) for receiving MBS data on SPS radio resources to a UE (e.g., events 302, 301, 303, 305, 402, 501, 503, 602, 702, 802, 902). In block 1704, the base station provides an indication to the UE to activate receiving MBS data according to the configuration (e.g., events 304, 380, 404, 501, 503, 604, 704, 880, 904). In block 1706, the base station transmits MBS data to the UE according to the configuration (e.g., events 312, 382, ​​380, 410, 582, 682, 782, 882, 906).

[0093] In some implementations, the base station provides the instruction that can be included in a configuration (e.g., the configuration can implicitly instruct the UE to activate receiving MBS data according to the configuration, or the configuration can include the instruction as an information element). In other implementations, providing the instruction includes transmitting a message (e.g., an RRC reconfiguration message) formatted according to a protocol for controlling radio resources that includes the configuration and the instruction.

[0094] In yet other implementations, providing the indication includes transmitting a command (e.g., an SPS activation command) to activate receiving the MBS data according to the configuration. The command may be a DCI. The base station may transmit the command in a first time slot, and the command may include a time offset corresponding to the number of slots after the first time slot at which the UE should receive the MBS data. In some implementations, the base station transmits one or more additional commands to the UE before transmitting the MBS data. In other implementations, the base station transmits multiple commands to the UE at different respective periods of the SPS radio resource.

[0095] In some implementations, the configuration is a first configuration and the command includes a second configuration for receiving the MBS data. In such implementations, transmitting the MBS data further complies with at least the second configuration. For example, the second configuration may include a delta configuration that augments the first configuration.

[0096] The base station may, for example, indicate to the UE that the command is for activating reception of MBS data rather than unicast data. The base station may generate the command according to a format specific to the MBS and / or may include in the command an index value that identifies a configuration (i.e., an index value that identifies a configuration for receiving MBS data on SPS radio resources). Additionally or alternatively, the base station may scramble the CRC value of the command with an identifier associated with the MBS (e.g., a group RNTI or MBS-RNTI) and transmit the scrambled CRC value together with the command.

[0097] In the configuration and / or command, the base station may include an identifier for a resource to which the UE should send an acknowledgment for the command and / or an identifier for a resource to which the UE should send an acknowledgment for the MBS data. The base station may receive an acknowledgment from the UE, which may be an HARQ acknowledgment or an acknowledgment included in a MAC PDU. If the base station does not receive an acknowledgment (i.e., an acknowledgment for the command or the MBS data), the base station may send a second command to activate receiving the MBS data according to the configuration.

[0098] The base station may multicast or broadcast a command to multiple UEs including the UE, or may unicast a command to the UE. Similarly, the base station may multicast or broadcast a configuration to multiple UEs including the UE, or unicast the configuration to the UE. In some implementations, the configuration is a first SPS configuration, and the UE is the first UE. The base station may unicast the first SPS configuration and the second SPS configuration to the first UE and the second UE, respectively, and the second SPS configuration may be different from the first SPS configuration. Furthermore, to the same UE, the base station may send both a first configuration for receiving MBS data on the first SPS resource and a second SPS configuration for receiving unicast data on the second SPS resource. The first and second SPS radio resources may have different periodicities.

[0099] Additionally, the base station may also send a deactivation command to the UE to instruct the UE to stop receiving MBS data according to the configuration.

[0100] 18 is a flow diagram of an example method 1800 for managing reception of MBS using SPS, which may be implemented by a UE. In block 1802, the UE receives a configuration for receiving MBS data on SPS radio resources from a base station (e.g., events 302, 301, 303, 305, 402, 501, 503, 602, 702, 802, 902). In block 1804, the UE determines that the UE activates receiving MBS data in accordance with the configuration (e.g., events 304, 380, 404, 501, 503, 604, 704, 880, 904). In block 1806, the UE receives MBS data from the base station in accordance with the configuration (e.g., events 312, 382, ​​380, 410, 582, 682, 782, 882, 906).

[0101] The following list of examples reflects various embodiments expressly contemplated by this disclosure.

[0102] Example 1. A method in a base station for managing transmission of multicast and / or broadcast services (MBS) using semi-persistent scheduling (SPS), the method comprising: transmitting, by processing hardware of the base station, a configuration to receive MBS data on SPS radio resources to a user equipment (UE); providing, by the processing hardware, an indication to the UE to activate receiving the MBS data in accordance with the configuration; and transmitting, by the processing hardware, the MBS data to the UE in accordance with the configuration.

[0103] Example 2. The method of example 1, wherein the instructions are included within the configuration.

[0104] Example 3. The method of example 1, wherein the step of providing the instructions includes the step of providing the instructions as an information element of the configuration.

[0105] Example 4. The method of Example 1, wherein providing the indication includes sending the indication along with the configuration in a message formatted according to a protocol for controlling radio resources.

[0106] Example 5. The method of Example 1, wherein providing the indication includes sending a command to activate receiving MBS data according to the configuration.

[0107] Example 6. The method of Example 5, wherein the command is a first command, and the method further includes, after transmitting the first command and before transmitting the MBS data, transmitting, by the processing hardware, a second command to the UE that activates receiving the MBS data according to the configuration.

[0108] Example 7. The method of Example 5, wherein the command is a first command, and the method further includes transmitting, by processing hardware, a plurality of commands to the UE at different respective periods of the SPS radio resource to activate receiving MBS data according to the configuration.

[0109] Example 8. The method of any one of Examples 5-7, wherein the configuration is a first configuration, the command includes a second configuration for receiving MBS data, and the step of transmitting the MBS data further conforms to at least the second configuration.

[0110] Example 9. The method of any one of Examples 5-8, wherein the base station transmits the command in the first time slot, the command including a time offset corresponding to the number of slots after the first time slot at which the UE should receive the MBS data.

[0111] Example 10. The method of any one of Examples 5-9, wherein transmitting the command includes transmitting downlink control information (DCI).

[0112] Example 11. The method of any one of Examples 5-10, wherein transmitting the command includes generating the command according to a format specific to the MBS, and transmitting the generated command.

[0113] Example 12. The method of any one of Examples 5-11, wherein sending the command includes including in the command an index value that identifies the configuration.

[0114] Example 13. The method of any one of Examples 5-12, wherein transmitting the command includes scrambling, by processing hardware, a cyclic redundancy check (CRC) value of the command with an identifier associated with the MBS, and transmitting the scrambled CRC value with the command.

[0115] Example 14. The method of any one of Examples 5-13, wherein transmitting the configuration includes including, in the configuration, an identifier to a resource to which the UE should transmit an acknowledgment to the command.

[0116] Example 15. The method of any one of Examples 5-13, wherein transmitting the configuration includes including, in the configuration, an identifier to a resource on which the UE should transmit an acknowledgment for the MBS data.

[0117] Example 16. The method of any one of Examples 5-13, wherein transmitting the command includes including within the command an identifier to a resource to which the UE should transmit an acknowledgment for the command.

[0118] Example 17. The method of any one of Examples 5-13, wherein transmitting the command includes including within the command an identifier to a resource on which the UE should transmit an acknowledgment for the MBS data.

[0119] Example 18. The method of any one of Examples 14-17, further comprising receiving, by processing hardware, an acknowledgement from the UE, wherein the acknowledgement is a Hybrid Automatic Repeat Request (HARQ) acknowledgement.

[0120] Example 19. The method of any one of Examples 14-17, further comprising receiving, by processing hardware, an acknowledgment from the UE in a Medium Access Control (MAC) Protocol Data Unit (PDU).

[0121] Example 20. The method of any one of Examples 14-17, wherein the command is a first command, and the method further includes, in response to not receiving an acknowledgment at the resource, sending, by the processing hardware, a second command to activate receiving MBS data according to the configuration.

[0122] Example 21. The method of any one of Examples 5-20, wherein transmitting the command includes multicasting or broadcasting the command to a plurality of UEs, including the UE.

[0123] Example 22. The method of any one of Examples 5-20, wherein transmitting the command includes unicasting the command to the UE.

[0124] Example 23. The method of any one of the preceding examples, wherein transmitting the configuration includes multicasting or broadcasting the configuration to a plurality of UEs, including the UE.

[0125] Example 24. The method of any one of the preceding examples, wherein transmitting the configuration includes unicasting the configuration to the UE.

[0126] Example 25. The method of Example 24, wherein the UE is a first UE, the configuration is a first SPS configuration, and the method further includes unicasting, by processing hardware, a second SPS configuration to the second UE for receiving MBS data on the SPS radio resources, wherein the second SPS configuration is different from the first SPS configuration.

[0127] Example 26. The method of any one of Examples 1-24, wherein the configuration is a first SPS configuration, the SPS radio resource is a first SPS radio resource, and the method further includes transmitting, by processing hardware, a second SPS configuration to the UE for receiving unicast data on the second SPS radio resource.

[0128] Example 27. The method of Example 26, wherein the first and second SPS radio resources have different periodicities.

[0129] Example 28. The method of any one of the preceding examples, further comprising transmitting, by processing hardware, a deactivation command to instruct the UE to stop receiving MBS data according to the configuration.

[0130] Example 29. A base station including processing hardware and configured to perform a method according to any one of the preceding examples.

[0131] Example 30. A method in a user equipment (UE) for managing reception of multicast and / or broadcast services (MBS) using semi-persistent scheduling (SPS), the method comprising: receiving, by processing hardware of the UE, a configuration from a base station for receiving MBS data on SPS radio resources; determining, by the processing hardware, to activate the UE to receive the MBS data in accordance with the configuration; and receiving, by the processing hardware, the MBS data from the base station in accordance with the configuration.

[0132] Example 31. The method of example 30, wherein the determining step is responsive to the configuration.

[0133] Example 32. The method of example 30, wherein the determining step is responsive to an information element included in the configuration.

[0134] Example 33. The method of Example 30, wherein the determining step includes receiving a message including a configuration and an instruction to activate receiving MBS data in accordance with the configuration, the message formatted in accordance with a protocol for controlling radio resources, and determining, in response to the instruction, to activate receiving MBS data in accordance with the configuration.

[0135] Example 34. The method of Example 30, further comprising receiving, by the processing hardware, a command to activate receiving MBS data according to the configuration, wherein the determining step is responsive to the command.

[0136] Example 35. The method of Example 34, wherein the configuration is a first configuration, the command includes a second configuration for receiving the MBS data, and the step of receiving the MBS data is further in accordance with at least the second configuration.

[0137] Example 36. The method of Example 34 or 35, wherein the UE receives the command in the first time slot, the command including a time offset corresponding to the number of slots after the first time slot at which the UE should receive the MBS data.

[0138] Example 37. The method of any one of Examples 34-36, wherein receiving a command includes receiving downlink control information (DCI).

[0139] Example 38. The method of any one of Examples 34-37, wherein receiving the command includes determining that the command is formatted according to a format specific to the MBS, and determining, based on the format, that the command activates receiving MBS data according to the configuration.

[0140] Example 39. The method of any one of Examples 34-37, wherein receiving the command includes determining that the command includes an index value that identifies a configuration, and determining, based on the index value, that the command activates receiving MBS data in accordance with the configuration.

[0141] Example 40. The method of any one of Examples 34-39, wherein receiving the command includes descrambling a cyclic redundancy check (CRC) value received with the command using an identifier associated with the MBS.

[0142] Example 41. The method of any one of Examples 34-40, wherein the configuration or command includes an identifier to a resource to which the UE should send an acknowledgment for the command, and the method further includes, in response to receiving the command, sending, by the processing hardware, an acknowledgment for the command on the resource to the base station.

[0143] Example 42. The method of any one of Examples 34-40, wherein the configuration or command includes an identifier to a resource to which the UE should transmit an acknowledgment for the MBS data, and the method further includes, in response to receiving the MBS data, transmitting, by the processing hardware, an acknowledgment for the MBS data on the resource to the base station.

[0144] Example 43. The method of example 41 or 42, wherein transmitting an acknowledgment includes transmitting a hybrid automatic repeat request (HARQ) acknowledgment.

[0145] Example 44. The method of Example 41 or 42, wherein transmitting the acknowledgment includes transmitting the acknowledgment in a medium access control (MAC) protocol data unit (PDU).

[0146] Example 45. The method of any one of Examples 30-44, wherein the configuration is a first SPS configuration, the SPS radio resource is a first SPS radio resource, and the method further includes receiving, by the processing hardware, from the base station a second SPS configuration for receiving unicast data on the second SPS radio resource.

[0147] Example 46. The method of Example 45, wherein the first and second SPS radio resources have different periodicities.

[0148] Example 47. The method of any one of Examples 30-46, further comprising receiving, by the processing hardware, a deactivation command from the base station instructing the UE to stop receiving MBS data according to the configuration.

[0149] Example 48. User equipment (UE) including processing hardware and configured to implement a method according to any one of Examples 30-47.

[0150] The following additional considerations apply to the preceding discussion:

[0151] A user device (e.g., UE 102) in which the techniques of this disclosure may be implemented may be any suitable device capable of wireless communication, such as a smartphone, tablet computer, laptop computer, mobile game console, point-of-sale (POS) terminal, health monitoring device, drone, camera, media streaming dongle or another personal media device, wearable device such as a smartwatch, wireless hotspot, femtocell, or broadband router. Furthermore, in some cases, the user device may be integrated into an electronic system such as a vehicle head unit or advanced driver assistance system (ADAS). Furthermore, the user device may operate as an Internet of Things (IoT) device or a mobile internet device (MID). Depending on the type, the user device may include one or more general-purpose processors, computer-readable memory, a user interface, one or more network interfaces, one or more sensors, etc.

[0152] Certain embodiments are described in this disclosure as including logic or several components or modules. A module may be a software module (e.g., code stored on a non-transitory machine-readable medium) or a hardware module. A hardware module is a tangible unit capable of performing specific operations and may be configured or arranged in a specific way. A hardware module may comprise dedicated circuitry or logic that is permanently configured to perform specific operations (e.g., as a dedicated processor such as a field programmable gate array (FPGA) or application-specific integrated circuit (ASIC)). A hardware module may also comprise programmable logic or circuitry that is temporarily configured by software to perform specific operations (e.g., as contained within a general-purpose processor or other programmable processor). The decision whether to implement a hardware module in dedicated, permanently configured circuitry or in temporarily configured (e.g., configured by software) circuitry may be driven by cost and time considerations.

[0153] If implemented in software, the techniques may be provided as part of an operating system, a library used by multiple applications, a specific software application, etc. The software may be executed by one or more general-purpose processors or one or more special-purpose processors. [Explanation of symbols]

[0154] 100 Wireless communication system, wireless communication network 102UE 102A UE 102B UE 104 Base station, MeNB, Mng-eNB, MgNB 105 RAN 106A base station, SgNB, Sng-eNB 106B base station 110 Core Network (CN), CN 111 Evolved Packet Core (EPC), EPC 112 Serving Gateway (SGW), SGW 114 Mobility Management Entity (MME), MME 116 Packet Data Network Gateway (PGW), PGW 124 cells 126A cell 126B cell 130 Processing Hardware 132 Base Station MBS Controller 134 Base Station Non-MBS Controller 140 Processing Hardware 142 Base Station MBS Controller 144 Base Station Non-MBS Controller 150 Processing Hardware 152 UE MBS Controller 154 UE non-MBS controller 160 5th Generation Core (5GC), 5GC 162 User Plane Function (UPF), UPF 164 Access and Mobility Management (AMF), AMF 166 Session Management Facility (SMF), SMF 172 Central Unit (CU), CU 172A Logical Node CU-CP 172B Logical node CU-UP 174 Distributed Unit (DU), DU 200 Protocol Stack, Stack 202A Physical Layer (PHY) 202B NR PHY 204A EUTRA MAC Sublayer 204B NR MAC sublayer 206A EUTRA RLC sublayer, EUTRA RLC, RLC layer 206B NR RLC sublayer 208 EUTRA PDCP Sublayer 210 NR PDCP sublayer, NR PDCP 212 SDAP Sublayer 300A Scenario 300B Scenario 301 Events 302 Events 303 Events 304 Events 305 MBS configuration procedures and events 306 Events 308 Events 312 Events 314 Events 316 Events 318 Events 320 blocks 322 blocks 380 MBS SPS Activation Procedure, MBS Activation Procedure, Event 382 MBS SPS data transmission procedure, MBS data packet transmission procedure, event 383 MBS SPS Activation and Data Transmission Procedures 384 blocks 400 Scenarios 402 Events 404 Event 407 Events 409 Events 410 Events 411 Event 412 Events 414 Events 416 Events Block 423 481 Events 483 MBS SPS Activation and Data Transmission Procedures 484 blocks 500 Scenarios 501 Event 503 Events 582 Events 600A Scenario 600B Scenario 602 Events 604 Events 606 Events 620 Events, Blocks 622 Events, Blocks 626 Events 627 Events 629 Events 680 MBS SPS Activation Procedure 681 MBS SPS Activation Procedure 682 Procedure, MBS Data Packet Transmission Procedure, Event 684 MBS SPS Deactivation Procedure, Procedure 685 MBS SPS Deactivation Procedure 700 Scenarios 702 Events 704 Events 706 Events 782 MBS data packet transmission procedure, event 784 blocks 800 Scenarios 802 Events 808 Events 810 Events 812 Events 814 Events 880 Events 882 MBS data packet transmission procedure, event 884 blocks 900 Scenarios 902 Events 904 Events 906 Events 914 Block

Claims

1. 1. A method in a base station for managing transmission of multicast and / or broadcast services (MBS) using semi-persistent scheduling (SPS), comprising: unicasting, by processing hardware of the base station, a configuration to receive MBS data on SPS radio resources to a user equipment (UE); providing, by the processing hardware, an indication to the UE to activate receiving the MBS data according to the configuration; and transmitting, by the processing hardware, the MBS data to the UE according to the configuration.

2. providing the instructions, providing said instructions as information elements of said configuration; or 10. The method of claim 1, comprising at least one of the steps of: transmitting the indication along with the configuration in a message formatted according to a protocol for controlling radio resources.

3. providing the instructions, The method of claim 1 , comprising sending a command to activate receiving the MBS data according to the configuration.

4. the command is a first command, and the method comprises:

4. The method of claim 3, further comprising: after transmitting the first command and before transmitting the MBS data, transmitting, by the processing hardware, a second command to the UE to activate receiving the MBS data according to the configuration.

5. the command is a first command, and the method comprises:

4. The method of claim 3, further comprising: transmitting, by the processing hardware, a plurality of commands to the UE at different respective periods of the SPS radio resource to activate receiving the MBS data according to the configuration.

6. the base station transmits the command in a first time slot; 6. The method of claim 3, wherein the command includes a time offset corresponding to the number of slots after the first time slot at which the UE should receive the MBS data.

7. transmitting the configuration, 7. The method of claim 3, comprising including within the configuration: (i) an identifier to a resource on which the UE should transmit an acknowledgement to the command; and (ii) a physical uplink control channel (PUCCH) resource indicator within the command.

8. transmitting the configuration, 8. The method of claim 3, comprising including in the configuration an identifier for a Downlink Control Information (DCI) format.

9. the step of sending the command comprises:

9. The method of claim 3, comprising including in the command at least one of a frequency domain resource allocation field, a time domain resource allocation field, a modulation and coding scheme (MCS), a new data indicator, a redundancy version, a virtual resource block (VRB) to physical resource block (PRB) mapping, or a physical downlink shared channel (PDSCH) to hybrid automatic repeat request (HARQ) feedback timing indicator.

10. the UE is a first UE, the configuration is a first SPS configuration, and the method comprises:

10. The method of claim 1, further comprising: unicasting, by the processing hardware, a second SPS configuration to a second UE for receiving MBS data on the SPS radio resources, wherein the second SPS configuration is different from the first SPS configuration.

11. the configuration is a first SPS configuration, the SPS radio resource is a first SPS radio resource, and the method includes:

10. The method of claim 1, further comprising: transmitting, by the processing hardware, a second SPS configuration to the UE for receiving unicast data on a second SPS radio resource.

12. A base station comprising processing hardware and configured to implement the method of any one of claims 1 to 11.

13. 1. A method in a user equipment (UE) for managing reception of multicast and / or broadcast services (MBS) using semi-persistent scheduling (SPS), comprising: receiving, by processing hardware of the UE, configuration from a base station on resources dedicated to the UE for receiving MBS data on SPS radio resources; determining, by the processing hardware, that the UE activates receiving the MBS data according to the configuration; receiving, by the processing hardware, the MBS data from the base station in accordance with the configuration.

14. the determining step: (i) determining by the UE to activate receiving the MBS data in response to an information element included in the configuration; or 14. The method of claim 13, comprising at least one of the following steps: (ii) receiving a message including the configuration and an instruction to activate receiving the MBS data in accordance with the configuration, the message being formatted in accordance with a protocol for controlling radio resources; and, in response to the instruction, determining to activate receiving the MBS data in accordance with the configuration.

15. receiving, by the processing hardware, a command to activate receiving the MBS data in accordance with the configuration; The method of claim 13 , wherein the determining step is responsive to the command.

16. and wherein the configuration includes: (i) an identifier to a resource on which the UE should transmit an acknowledgment for the command; and (ii) a physical uplink control channel (PUCCH) resource indicator in the command; 16. The method of claim 15, further comprising the step of, in response to receiving the command, transmitting, by the processing hardware, an acknowledgment for the command on the resource to the base station.

17. 17. The method of claim 15 or 16, wherein the configuration includes an identifier for a downlink control information (DCI) format.

18. 18. The method of claim 15, wherein the command includes at least one of a frequency domain resource allocation field, a time domain resource allocation field, a modulation and coding scheme (MCS), a new data indicator, a redundancy version, a virtual resource block (VRB) to physical resource block (PRB) mapping, or a physical downlink shared channel (PDSCH) to hybrid automatic repeat request (HARQ) feedback timing indicator.

19. the configuration is a first SPS configuration, the SPS radio resource is a first SPS radio resource, and the method includes:

19. The method of claim 13, further comprising receiving, by the processing hardware, from the base station a second SPS configuration for receiving unicast data on a second SPS radio resource.

20. 20. User Equipment (UE) comprising processing hardware and configured to implement the method of any one of claims 13 to 19.

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