Mapping Multicast Broadcast Service Quality Flows to Logical Channel Identifiers

Abstract

Generally speaking, various aspects of the present disclosure relate to wireless communication. In some aspects, a user equipment (UE) may receive an indication of a pattern for mapping a multicast broadcast quality of service (MB-QoS) flow to a logical channel identifier and a group radio network temporary identifier (G-RNTI); identify the MB-QoS flow from a media access control (MAC) transport block (TB) at least partially based on the indicated pattern; and decode data included in the MB-QoS flow. A number of other aspects are provided.

Description

[0001] This application is a divisional application of a Chinese patent application with an application date of August 21, 2020, an application number of 202080059060.4, and an invention title of "Mapping Multicast Broadcast Quality of Service Flows to Logical Channel Identifiers".

[0002] Cross - reference to related applications

[0003] This patent application claims the benefit of priority of a U.S. Provisional Patent Application filed on August 30, 2019, with Serial No. 62 / 894,582 and title "MAPPING MULTICAST BROADCAST QUALITY OF SERVICE FLOWS TO LOGICAL CHANNEL IDENTIFIERS", and a U.S. Non - Provisional Patent Application filed on August 20, 2020, with Serial No. 16 / 998,608 and title "MAPPING MULTICAST BROADCAST QUALITY OF SERVICE FLOWS TO LOGICAL CHANNEL IDENTIFIERS", the disclosures of which are hereby incorporated herein by reference in their entireties. Technical field

[0004] Broadly speaking, aspects of the present disclosure relate to wireless communication, and more particularly, to techniques and apparatus for mapping multicast broadcast quality of service flows to logical channel identifiers. Background art

[0005] Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasting. A typical wireless communication system may use multiple access technologies that are capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, etc. or a combination thereof). Examples of such multiple access technologies include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, Single - Carrier Frequency Division Multiple Access (SC - FDMA) systems, Time Division Synchronous Code Division Multiple Access (TD - SCDMA) systems, and Long Term Evolution (LTE). LTE / Advanced LTE is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard released by the Third Generation Partnership Project (3GPP).

[0006] The above multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different user equipments (UEs) to communicate at the urban, national, regional, and even global levels. New Radio (NR) (which may also be referred to as 5G) is a set of enhancements to the LTE mobile standard released by 3GPP. NR is designed to better support mobile broadband Internet access by improving spectral efficiency, reducing costs, enhancing services, using new spectrums, and better integrating with other open standards that use Orthogonal Frequency Division Multiplexing (OFDM) with Cyclic Prefix (CP) (CP-OFDM) on the downlink (DL) and CP-OFDM or SC-FDM (e.g., also referred to as Discrete Fourier Transform Spread OFDM (DFT-s-OFDM)) on the uplink (UL), as well as supporting beamforming, Multiple-Input Multiple-Output (MIMO) antenna technology, and carrier aggregation. However, as the demand for mobile broadband access continues to increase, further improvements to LTE and NR technologies are needed. Preferably, these improvements are applicable to other multiple access technologies and telecommunication standards that use these technologies.

[0007] In Long Term Evolution (LTE) Single Cell Point-to-Multipoint (SC-PTM), a single logical channel identifier is used for both the Single Cell Multicast Broadcast Control Channel (SC-MCCH) that carries multicast broadcast control information and the Single Cell Multicast Broadcast Traffic Channel (SC-MTCH) that carries multicast broadcast services. As a result, LTE SC-PTM does not support retransmission because different SC-MTCHs are not uniquely identifiable, and thus the UE cannot indicate to the base station which data to retransmit. Additionally, LTE SC-PTM is a multicast / broadcast-only system, and communication cannot be switched between multicast / broadcast and unicast, such as for retransmission to a single UE or individual retransmission to a small group of UEs. Summary of the Invention

[0008] In some aspects, a method of wireless communication performed by a user equipment (UE) may include: receiving an indication of a mode for mapping a Multicast Broadcast Quality of Service (MB-QoS) flow to a logical channel identifier and a Group Radio Network Temporary Identifier (G-RNTI); identifying the MB-QoS flow from a Medium Access Control (MAC) Transport Block (TB) at least in part based on the indicated mode; and decoding data included in the MB-QoS flow.

[0009] In some aspects, a UE for wireless communication may include a memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to: receive an indication of a pattern for mapping an MB-QoS flow to a logical channel identifier and a G-RNTI; identify the MB-QoS flow from a MAC TB at least in part based on the indicated pattern; and decode data included in the MB-QoS flow.

[0010] In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a UE, may cause the one or more processors to: receive an indication of a pattern for mapping an MB-QoS flow to a logical channel identifier and a G-RNTI; identify the MB-QoS flow from a MAC TB at least in part based on the indicated pattern; and decode data included in the MB-QoS flow.

[0011] In some aspects, an apparatus for wireless communication may include: means for receiving an indication of a pattern for mapping an MB-QoS flow to a logical channel identifier and a G-RNTI; means for identifying the MB-QoS flow from a MAC TB at least in part based on the indicated pattern; and means for decoding data included in the MB-QoS flow.

[0012] Aspects generally include methods, apparatuses, systems, computer program products, non-transitory computer-readable media, user equipments, base stations, wireless communication devices, or processing systems as generally described with reference to the figures and the description and as illustrated by the figures and the description.

[0013] The foregoing has outlined rather broadly the features and technical advantages of examples according to the present disclosure so that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter. The concepts disclosed and specific examples may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent structures do not depart from the scope of the appended claims. When considered in conjunction with the accompanying figures, the characteristics (both structural organization and method of operation) of the concepts disclosed herein, as well as associated advantages, will be better understood. Each of the figures in the drawings is provided for purposes of illustration and description and is not to be construed as defining the scope of the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] To be able to understand the above features of the present disclosure in detail, a more specific description of what was briefly summarized above can be referred to in terms of various aspects, and some of the aspects are shown in the accompanying drawings. However, it should be noted that the drawings only show some exemplary aspects of the present disclosure and should not be considered as limiting the scope of the present disclosure, as the description allows other equivalent aspects. The same reference numerals in different drawings can identify the same or similar elements.

[0015] Figure 1 FIG. is a diagram showing an example wireless network according to various aspects of the present disclosure.

[0016] Figure 2 FIG. is a diagram showing an example of a base station (BS) communicating with a user equipment (UE) in a wireless network according to various aspects of the present disclosure.

[0017] Figure 3 FIG. is a diagram showing an example logical architecture of a distributed radio access network (RAN) according to various aspects of the present disclosure.

[0018] Figure 4 FIG. is a diagram showing an example physical architecture of a distributed RAN according to various aspects of the present disclosure.

[0019] Figure 5 FIG. is a diagram showing an example channel mapping for multicast / broadcast communication according to various aspects of the present disclosure.

[0020] Figures 6 - 11 FIG. is a diagram showing an example of mapping a multicast / broadcast quality of service flow to a logical channel identifier according to various aspects of the present disclosure.

[0021] Figure 12 FIG. is a diagram showing an example process performed by a UE according to various aspects of the present disclosure.

[0022] Figure 13 FIG. is a block diagram of an example apparatus for wireless communication according to various aspects of the present disclosure. Detailed Description

[0023] Aspects of the present disclosure are described more fully hereinafter with reference to the accompanying drawings. However, the present disclosure may be embodied in many different forms and should not be construed as limited to any specific structure or function presented throughout this disclosure. Rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art. Based on the teachings herein, those skilled in the art will appreciate that the scope of the present disclosure is intended to cover any aspect of the disclosure disclosed herein, whether implemented independently of any other aspect of the present disclosure or in combination with any other aspect of the present disclosure. For example, any number of the aspects set forth herein may be used to implement a device or practice a method. In addition, the scope of the present disclosure is intended to cover such devices or methods practiced using other structures, functions, or combinations of structures and functions in addition to or different from the aspects of the disclosure set forth herein. Any aspect of the disclosure disclosed herein may be embodied by one or more elements of a claim.

[0024] Certain aspects of a telecommunications system will now be presented with reference to various devices and techniques. These devices and techniques will be described in the following detailed description and are illustrated in the accompanying drawings by various boxes, modules, components, circuits, steps, processes, algorithms, etc., or combinations thereof (collectively referred to as "elements"). These elements may be implemented using hardware, software, or a combination thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

[0025] Various aspects generally involve mapping multicast broadcast quality of service (MB-QoS) flows to logical channel identifiers. Some aspects more specifically involve mapping each MB-QoS flow to a different combination of a logical channel identifier (LCID) and a group radio network temporary identifier (G-RNTI). In some aspects, each MB-QoS flow in a set of MB-QoS flows is mapped to a different LCID and is mapped to a different G-RNTI. In other aspects, each MB-QoS flow in a set of MB-QoS flows is mapped to a different LCID and is mapped to a common G-RNTI for multiple MB-QoS flows. In other aspects, each MB-QoS flow in a set of MB-QoS flows is mapped to a different G-RNTI and is mapped to a common LCID for multiple MB-QoS flows. In other aspects, each MB-QoS flow in a set of MB-QoS flows is mapped to a fixed LCID for all MB-QoS flows and is mapped to at least one of a G-RNTI or a multicast broadcast radio bearer (MRB) identifier that identifies the service type of the MB-QoS flow. In other aspects, each MB-QoS flow in a set of MB-QoS flows is mapped to a first LCID and G-RNTI for multicast or broadcast transmission and is mapped to a second LCID and a cell radio network temporary identifier (C-RNTI) associated with unicast transmission.

[0026] Certain aspects of the subject matter described in this disclosure can be implemented to realize one or more of the following potential advantages. In some examples, the techniques described can be used to implement retransmission of communication of MB-QoS flows for higher reliability, such as by using acknowledgment (ACK) or negative acknowledgment (NACK) (collectively ACK / NACK) feedback. In some examples, the techniques described can be used to enable such retransmissions to be sent in multicast / broadcast communication or in unicast communication (e.g., for new radio hybrid mode communication), thereby increasing system flexibility and, in some cases, saving network resources and user equipment (UE) resources by sending the retransmission to a single UE rather than a group of UEs.

[0027] Figure 1FIG. is a diagram illustrating an example wireless network in accordance with various aspects of the present disclosure. The wireless network may be a Long Term Evolution (LTE) network or some other wireless network, such as a 5G or NR network. The wireless network may include a large number of base stations (BSs) 110 (shown as BS 110a, BS 110b, BS 110c, and BS 110d) and other network entities. A BS is an entity that communicates with user equipment (UEs), and may also be referred to as a Node B, eNodeB, eNB, gNB, NR BS, 5G Node B (NB), access point (AP), transmit receive point (TRP), etc., or a combination thereof (these terms may be used interchangeably herein). Each BS may provide communication coverage for a specific geographic area. In 3GPP, the term "cell" may refer to the coverage area of a BS or the BS subsystem serving that coverage area, depending on the context in which the term is used.

[0028] A BS may provide communication coverage for a macro cell, a pico cell, a femto cell, or another type of cell. A macro cell may cover a relatively large geographic area (e.g., with a radius of several kilometers) and allow unrestricted access by UEs with service subscriptions. A pico cell may cover a relatively small geographic area and allow unrestricted access by UEs with service subscriptions. A femto cell may cover a relatively small geographic area (e.g., a residence) and may allow restricted access by UEs associated with that femto cell (e.g., UEs in a Closed Subscriber Group (CSG)). The BS for a macro cell may be referred to as a macro BS. The BS for a pico cell may be referred to as a pico BS. The BS for a femto cell may be referred to as a femto BS or a home BS. A BS may support one or more (e.g., three) cells.

[0029] The wireless network may be a heterogeneous network including different types of BSs (e.g., macro BSs, pico BSs, femto BSs, relay BSs, etc., or a combination thereof). These different types of BSs may have different transmit power levels, different coverage areas, and different impacts on interference in the wireless network. For example, a macro BS may have a relatively high transmit power level (e.g., 5 to 40 watts), while pico BSs, femto BSs, and relay BSs may have relatively low transmit power levels (e.g., 0.1 to 2 watts). In Figure 1In the example shown, BS 110a can be a macro BS for macro cell 102a; BS 110b can be a pico BS for pico cell 102b; and BS 110c can be a femto BS for femto cell 102c. Network controller 130 can be coupled to a collection of BSs 102a, 102b, 110a, and 110b, and can provide coordination and control for these BSs. Network controller 130 can communicate with the BSs via a backhaul. The BSs can also communicate with each other directly or indirectly via a wireless backhaul or a wired backhaul, such as, for example.

[0030] In some aspects, a cell can be non-stationary, instead, the geographical area of the cell can move according to the location of a mobile BS. In some aspects, BSs can be interconnected with each other or interconnected to one or more other BSs or network nodes (not shown) in a wireless network using any suitable transport network via various types of backhaul interfaces (such as direct physical connections, virtual networks, etc., or combinations thereof).

[0031] The wireless network can also include relay stations. A relay station is an entity that can receive a data transmission from an upstream station (e.g., a BS or a UE) and send the data transmission to a downstream station (e.g., a UE or a BS). A relay station can also be a UE capable of relaying transmissions for other UEs. In Figure 1 the example shown, relay station 110d can communicate with macro BS 110a and UE 120d to facilitate communication between BS 110a and UE 120d. A relay station can also be referred to as a relay BS, a relay base station, a repeater, etc., or combinations thereof.

[0032] UEs 120 (e.g., 120a, 120b, 120c) can be spread throughout the wireless network, and each UE can be fixed or mobile. A UE can also be referred to as an access terminal, a terminal, a mobile station, a user unit, a station, etc., or combinations thereof. A UE can be a cellular phone (e.g., a smart phone), a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet computer, a camera, a gaming device, a netbook, a smartbook, a superbook, a medical device or equipment, a biometric sensor / device, a wearable device (smart watch, smart clothing, smart glasses, smart wristband, smart jewelry (e.g., smart ring, smart bracelet)), an entertainment device (e.g., a music or video device, or a satellite radio unit), a vehicle component or sensor, a smart meter / sensor, an industrial manufacturing device, a global positioning system device, or any other suitable device configured to communicate via a wireless medium.

[0033] Some UEs can be considered as Machine-Type Communication (MTC) or evolved or enhanced Machine-Type Communication (eMTC) UEs. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, etc., or combinations thereof, that can communicate with a base station, another device (e.g., a remote device), or other entities. A wireless node can provide a connection to a network or to the network (e.g., a wide area network such as the Internet or a cellular network) via a wired or wireless communication link. Some UEs can be considered Internet of Things (IoT) devices, or can be implemented as NarrowBand IoT (NB-IoT) devices. Some UEs can be considered Customer Premises Equipment (CPE). UE 120 can be included within a housing that houses components of UE 120, such as a processor component, a memory component, etc., or combinations thereof.

[0034] Generally speaking, any number of wireless networks can be deployed in a given geographical area. Each wireless network can support a specific Radio Access Technology (RAT) and can operate on one or more frequencies or frequency channels. A frequency can also be referred to as a carrier, etc., or combinations thereof. Each frequency can support a single RAT in a given geographical area to avoid interference between wireless networks of different RATs. In some cases, an NR or 5G RAT network can be deployed.

[0035] In some aspects, two or more UEs 120 (e.g., shown as UE 120a and UE 120e) can communicate directly with each other using one or more sidelink channels (e.g., without using base station 110 as an intermediate device). For example, UE 120 can use peer-to-peer (P2P) communication, device-to-device (D2D) communication, vehicle-to-everything (V2X) protocols (e.g., which can include vehicle-to-vehicle (V2V) protocols, vehicle-to-infrastructure (V2I) protocols, etc., or combinations thereof), mesh networks, etc., or combinations thereof. In such cases, UE 120 can perform scheduling operations, resource selection operations, or other operations described elsewhere herein as performed by base station 110.

[0036] Figure 2 FIG. is a diagram showing an example base station (BS) communicating with a user equipment (UE) in a wireless network according to various aspects of the present disclosure. Base station 110 can be equipped with T antennas 234a through 234t, and UE 120 can be equipped with R antennas 252a through 252r, where typically T≥1 and R≥1.

[0037] At base station 110, transmit processor 220 may receive data for one or more UEs from data source 212, select one or more modulation and coding schemes (MCSs) for each UE at least in part based on channel quality indicators (CQIs) received from each UE, process (e.g., encode) the data for each UE at least in part based on the selected MCSs for each UE, and provide data symbols for all UEs. Transmit processor 220 may also process system information (e.g., for semi-static resource partitioning information (SRPI), etc., or a combination thereof) and control information (e.g., CQI requests, grants, upper layer signaling, etc., or a combination thereof), and provide overhead symbols and control symbols. Transmit processor 220 may also generate reference symbols for reference signals (e.g., cell-specific reference signals (CRSs)) and synchronization signals (e.g., primary synchronization signal (PSS) and secondary synchronization signal (SSS)). Transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, control symbols, overhead symbols, or reference symbols (if applicable), and may provide T output symbol streams to T modulators (MODs) 232a through 232t. Each MOD 232 may process the corresponding output symbol stream (e.g., for OFDM, etc., or a combination thereof) to obtain an output sample stream. Each MOD 232 may further process the output sample stream (e.g., transform to analog, amplify, filter, and up-convert) to obtain a downlink signal. The T downlink signals from MODs 232a through 232t may be transmitted via T antennas 234a through 234t, respectively. According to various aspects described in more detail below, position coding may be utilized to generate synchronization signals to convey additional information.

[0038] At the UE 120, antennas 252a through 252r may receive downlink signals from the base station 110 or other base stations and may provide the received signals to R demodulators (DEMODs) 254a through 254r, respectively. Each DEMOD 254 may condition (e.g., filter, amplify, down-convert, and digitize) the received signal to obtain input samples. Each DEMOD 254 may further process the input samples (e.g., for OFDM, etc., or combinations thereof) to obtain received symbols. The MIMO detector 256 may obtain the received symbols from all R DEMODs 254a through 254r, perform MIMO detection (if applicable) on the received symbols, and provide the detected symbols. The receive processor 258 may process (e.g., decode) the detected symbols, provide the decoded data for the UE 120 to the data sink 260, and provide the decoded control information and system information to the controller / processor 280. The channel processor may determine a reference signal received power (RSRP), a received signal strength indicator (RSSI), a reference signal received quality (RSRQ), a channel quality indicator (CQI), etc., or combinations thereof. In some aspects, one or more components of the UE 120 may be included in a housing.

[0039] On the uplink, at the UE 120, the transmit processor 264 may receive and process data from the data source 262 and control information from the controller / processor 280 (e.g., for a report including RSRP, RSSI, RSRQ, CQI, etc., or combinations thereof). The transmit processor 264 may also generate reference symbols for one or more reference signals. The symbols from the transmit processor 264 may be precoded (if applicable) by the TX MIMO processor 266, further processed (e.g., for discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM), orthogonal frequency division multiplexing with cyclic prefix (CP) (CP-OFDM), etc., or combinations thereof) by the MODs 254a through 254r, and transmitted to the base station 110. At the base station 110, the uplink signals from the UE 120 and other UEs may be received by the antenna 234, processed by the DEMOD 232, detected (if applicable) by the MIMO detector 236, and further processed by the receive processor 238 to obtain the decoded data and control information transmitted by the UE 120. The receive processor 238 may provide the decoded data to the data sink 239 and the decoded control information to the controller / processor 240. The base station 110 may include a communication unit 244 and communicate with the network controller 130 via the communication unit 244. The network controller 130 may include: a communication unit 294, a controller / processor 290, and a memory 292.

[0040] The controller / processor 240 of base station 110, the controller / processor 280 of UE 120, or Figure 2 any other component of may perform one or more techniques associated with mapping multicast broadcast service quality flows to logical channel identifiers, as described in more detail elsewhere herein. For example, the controller / processor 240 of base station 110, the controller / processor 280 of UE 120, or Figure 2 any other component of may perform or direct the operation of a process such as, for example, Figure 12 the processes described herein or other processes. Memories 242 and 282 may store data and program code for base station 110 and UE 120, respectively. Scheduler 246 may schedule UEs for data transmission on the downlink or uplink.

[0041] In some aspects, UE 120 may include: a unit for receiving an indication of a mode for mapping MB-QoS flows to logical channel identifiers and G-RNTIs; a unit for identifying MB-QoS flows from a medium access control (MAC) TB at least in part based on the indicated mode; a unit for decoding data included in the MB-QoS flows, etc., or a combination thereof. In some aspects, such units may include one or more components of UE 120 described in connection with Figure 2 .

[0042] Figure 3 is a diagram illustrating an example logical architecture of a distributed radio access network (RAN) in accordance with various aspects of the present disclosure. 5G access node 306 may include an access node controller (ANC) 302. The ANC may be a central unit (CU) of the distributed RAN. A backhaul interface to the next generation core network (NG-CN) 304 may terminate at the ANC. A backhaul interface 310 to an adjacent next generation access node (NG-AN) may terminate at the ANC. The ANC may include one or more TRPs 308 (which may also be referred to as BS, NR BS, Node B, 5G NB, AP, gNB, or some other term). As described above, a TRP may be used interchangeably with a "cell".

[0043] The TRP 308 may be a distributed unit (DU). The TRP may be connected to one ANC (ANC 302) or more than one ANC (not shown). For example, for RAN sharing, radio as a service (RaaS), and service-specific AND deployments, the TRP may be connected to more than one ANC. The TRP may include one or more antenna ports. The TRP may be configured to serve UEs traffic individually (e.g., dynamic selection) or jointly (e.g., joint transmission).

[0044] The local architecture of the RAN can be used to support fronthaul definition. The architecture can be defined to support fronthaul solutions across different deployment types. For example, the architecture can be at least partially based on the transmit network capabilities (e.g., bandwidth, latency, or jitter).

[0045] The architecture can share features or components with LTE. In some aspects, the NG-AN 310 can support dual connectivity with NR. The NG-AN 310 can share a common fronthaul for LTE and NR.

[0046] The architecture can enable cooperation between and within the TRPs 308. For example, cooperation can be preconfigured within or across the TRPs via the ANC 302. In some aspects, an inter-TRP interface may not be required / absent.

[0047] In some aspects, there can be a dynamic configuration of split logical functions within the RAN architecture. The Packet Data Convergence Protocol (PDCP), Radio Link Control (RLC), and MAC protocol layers can be adaptively placed at the ANC or the TRP.

[0048] Figure 4 FIG. is a diagram illustrating an example physical architecture of a distributed RAN in accordance with various aspects of the present disclosure. A centralized core network unit (C-CU) 402 can host core network functions. The C-CU can be centrally deployed. To handle peak capacity, the C-CU functions can be offloaded (e.g., to Advanced Wireless Services (AWS)). A centralized RAN unit (C-RU) 404 can host one or more ANC functions. Optionally, the C-RU can locally host core network functions. The C-RU can have a distributed deployment. The C-RU can be closer to the network edge. A distributed unit (DU) 406 can host one or more TRPs. The DU can be located at the network edge with radio frequency (RF) capabilities.

[0049] Figure 5FIG. is a diagram illustrating an example channel mapping for multicast / broadcast communication in accordance with various aspects of the present disclosure. As shown in block 502, a multicast broadcast traffic channel (MBTCH) and a multicast broadcast control channel (MBCCH) can be used to support multicast or broadcast transmissions in NR. The MBTCH can carry multicast or broadcast data, while the MBCCH can carry configuration information or control information for the multicast or broadcast communication to be sent on the MBTCH. The multicast or broadcast communication on the MBTCH can be addressed to a group of UEs using a G-RNTI. In some aspects, different MBTCHs can be used to carry multicast broadcast services with different quality of service (QoS) requirements. A multicast / broadcast service flow with associated QoS requirements or QoS parameters (e.g., a set of related packets for the same multicast / broadcast service) can be referred to as an MB-QoS flow. In some aspects, there can be a one-to-one mapping between an MB-QoS flow and an MBTCH. A base station or a core network device can configure a multicast broadcast radio bearer (MRB) for an MB-QoS flow. In some aspects, there can be a one-to-one mapping between an MB-QoS flow and an MRB. Thus, each MBTCH can correspond to an MRB for carrying an MB-QoS flow. The MBCCH can carry configuration information for configuring the MBTCH and can be addressed to all UEs in a cell (e.g., a physical cell or a virtual cell) using a single cell RNTI (SC-RNTI). In some aspects, there is a single MBCCH per cell (physical cell or virtual cell), and the MBCCH carries MBTCH configuration information for multiple multicast / broadcast services with different MB-QoS flows. As shown in block 504, the MBCCH and the MBTCH are logical channels and can be mapped to a downlink shared channel (DL-SCH) transport channel, which can be mapped to the PDSCH.

[0050] In LTE SC-PTM, a single logical channel identifier is used for both the single cell multicast broadcast control channel (SC-MCCH) that carries multicast broadcast control information and the single cell multicast broadcast traffic channel (SC-MTCH) that carries multicast broadcast traffic. LTE SC-PTM uses the RLC unacknowledged mode (UM), which does not support any retransmission and does not support MAC hybrid automatic repeat request (HARQ) or retransmission. LTE SC-PTM is a unicast / broadcast-only system, and communication cannot be switched between multicast / broadcast and unicast, such as for retransmission to a single UE or individual retransmission to a small group of UEs.

[0051] To support retransmission of multicast / broadcast communication in NR for higher reliability, different MB-QoS flows (e.g., carried on different MBTCHs) should be uniquely identifiable so that the UE can indicate to the base station the MB-QoS flow for which it needs retransmission. One way to uniquely identify an MB-QoS flow (or the corresponding MBTCH) is to use a different logical channel identifier (LCID) for each MG-QoS flow. However, to save signaling overhead, only a limited number of LCIDs (such as 13 reserved LCIDs) are available for mapping to MB-QoS flows. In NR, it may be necessary to support a large number of MB-QoS flows, such as up to 1024 MB-QoS flows. Thus, there are not enough available LCIDs to map each MB-QoS flow to a different LCID. Some of the techniques and apparatuses described herein allow different MB-QoS flows to be uniquely identified by mapping each MB-QoS flow to a different combination of an LCID and a G-RNTI. This allows retransmission of communication of MB-QoS flows, such as via use of acknowledgment (ACK) or negative acknowledgment (NACK) (collectively ACK / NACK) feedback, for higher reliability. Additionally, some of the techniques and apparatuses described herein allow such retransmission to be sent in multicast / broadcast communication or in unicast communication (e.g., for NR hybrid mode communication), thereby increasing system flexibility and, in some cases, saving network resources and UE resources by sending retransmissions to a single UE rather than a group of UEs.

[0052] Figure 6 is a diagram illustrating an example of mapping multicast broadcast quality of service flows to logical channel identifiers in accordance with various aspects of the present disclosure. As Figure 6 shown, base station 110 and UE 120 may communicate with each other.

[0053] In a first operation 605, base station 110 may send, and UE 120 may receive an indication of a pattern for mapping MB-QoS flows to logical channel identifiers and G-RNTIs. In some aspects, the pattern may include a first pattern in which each MB-QoS flow in a first set of MB-QoS flows is mapped to a different logical channel identifier and is mapped to a different G-RNTI, as described in more detail below in connection with Figure 7 Alternatively or additionally, the pattern may include a second pattern in which each MB-QoS flow in a second set of MB-QoS flows is mapped to a different logical channel identifier and is mapped to a common G-RNTI for multiple MB-QoS flows, as described in more detail below in connection with Figure 8described in more detail. Additionally or alternatively, the mode may include a third mode, in which each MB-QoS flow in the third set of MB-QoS flows is mapped to a different G-RNTI and is mapped to a common logical channel identifier for the multiple MB-QoS flows, as described in more detail below in conjunction with Figure 9 described in more detail. Additionally or alternatively, the mode may include a fourth mode, in which each MB-QoS flow in the fourth set of MB-QoS flows is mapped to a fixed logical channel identifier for all MB-QoS flows and is mapped to at least one of a G-RNTI or an MRB identifier identifying the service type of the MB-QoS flow, as described in more detail below in conjunction with Figure 10 described in more detail. Additionally or alternatively, the mode may include a fifth mode, in which each MB-QoS flow in the fifth set of MB-QoS flows is mapped to a first logical channel identifier and a G-RNTI for multicast or broadcast transmission and is mapped to a second logical channel identifier associated with the UE and a cell RNTI (C-RNTI) for unicast transmission, as described in more detail below in conjunction with Figure 11 described in more detail.

[0054] In some aspects, the base station 110 may configure and indicate a single mode for all MB-QoS flows. In some aspects, the base station 110 may configure two or more of the modes described herein (e.g., two or more of the first mode, the second mode, the third mode, the fourth mode, or the fifth mode). For example, the base station 110 may configure one mode for one set of MB-QoS flows and may configure another mode for another set of MB-QoS flows. In this way, the base station 110 may flexibly configure the MB-QoS flows according to, for example, the type of service provided by the MB-QoS flows, the traffic in the cell served by the base station 110, the number of UEs in the cell, the number of UEs subscribing to different MB-QoS flows, the traffic for different MB-QoS flows, etc.

[0055] In some aspects, the base station 110 can determine a mode for mapping MB-QoS flows to LCIDs and G-RNTIs at least in part based on whether the MB-QoS flow is a switchable MB-QoS flow or a non-switchable MB-QoS flow. A switchable MB-QoS flow can refer to an MB-QoS flow that can be switched between an MRB (for multicast / broadcast transmission) and a dedicated radio bearer (DRB) (for unicast transmission). A non-switchable MB-QoS flow can refer to an MB-QoS flow that cannot be switched between an MRB (for multicast / broadcast transmission) and a DRB (for unicast transmission). In some aspects, the base station 110 can indicate the mode in a radio resource control (RRC) message (e.g., an RRC configuration message, an RRC reconfiguration message, etc.), in downlink control information (DCI), in a medium access control (MAC) control element (CE) (collectively referred to as MAC-CE), in MBCCH communication, or in a combination thereof.

[0056] In a second operation 610, the base station 110 can send one or more medium access control (MAC) transport blocks (TBs) including a plurality of MB-QoS flows. In some aspects, the base station 110 can multiplex a plurality of MB-QoS flows in multicast / broadcast transmission using a single MAC TB (e.g., a single transmission of a single MAC TB or multiple transmissions of a single MAC TB). Additionally, the base station 110 can multiplex a plurality of MB-QoS flows in multicast / broadcast transmission using multiple (different) MAC TBs. In some aspects, the manner in which a plurality of MB-QoS flows are multiplexed in a single MAC TB or in multiple MAC TBs can depend on the mode for mapping MB-QoS flows to LCIDs and G-RNTIs, as described in more detail below in connection with Figures 8 - 12 The base station 110 can send an initial transmission of the MB-QoS flow in multicast / broadcast communication (e.g., using an MRB). The base station 110 can send a retransmission of the initial transmission in multicast / broadcast communication (e.g., using an MRB) or in unicast communication (e.g., using a DRB).

[0057] In a third operation 615, the UE 120 can identify one or more MB-QoS flows (e.g., one or more MB-QoS flows subscribed to by the UE 120) from the MAC TB at least in part based on the indicated mode for mapping MB-QoS flows to LCIDs and G-RNTIs. In some aspects, the manner in which the UE 120 identifies the MB-QoS flows subscribed to by the UE 120 can also depend on the mode for mapping MB-QoS flows to LCIDs and G-RNTIs, as described in more detail below in connection with Figures 8 - 12described in more detail. Additionally or alternatively, compared to identifying MB-QoS flows from unicast communications, the UE 120 may use different techniques to identify MB-QoS flows from multicast / broadcast communications, as described in more detail below in conjunction with Figures 8 - 12 described in more detail. In Figure 6 the example, the UE 120 subscribes to a first MB-QoS flow (MB-QoS1) and a third MB-QoS flow (MB-QoS3).

[0058] In a fourth operation 620, the UE 120 may decode data included in one or more of the identified MB-QoS flows. In some aspects, the UE 120 may use the LCID identifier and G-RNTI included in the MAC TB (e.g., in the MAC header or MAC sub-header) to identify data for the MB-QoS flow. The UE 120 may use the G-RNTI to descramble data for the MB-QoS flow in multicast / broadcast communications. Additionally or alternatively, the UE 120 may use the G-RNTI to identify MB-QoS flows in unicast communications. After identifying data for the MB-QoS flows subscribed to by the UE 120, the UE 120 may decode the data. In Figure 6 the example, the UE 120 may decode data for the first MB-QoS flow (MB-QoS1) and the third MB-QoS flow (MB-QoS3). By using one or more of the modes described herein, MB-QoS flows may be mapped to a limited number of LCIDs, which saves signaling overhead while also allowing retransmission of MB-QoS for improved reliability.

[0059] Figure 7 is a diagram illustrating another example of mapping multicast broadcast service quality flows to LCIDs in accordance with aspects of the present disclosure. Figure 7 illustrates a first mode in which each MB-QoS flow in a set of MB-QoS flows is mapped to a different logical channel identifier and is mapped to a different G-RNTI. As described above in conjunction with Figure 6 stated, in some aspects, the base station 110 may indicate to the UE 120 one or more modes for mapping MB-QoS flows to LCIDs and G-RNTIs.

[0060] In a first operation 705, in some aspects, different MB-QoS flows can be mapped to different LCIDs. For example, base station 110 can configure a one-to-one mapping between MB-QoS flows and LCIDs, where each MB-QoS flow is mapped to a different LCID. In a second operation 710, different MB-QoS flows can be mapped to different G-RNTIs. For example, base station 110 can configure a one-to-one mapping between MB-QoS flows and G-RNTIs, where each MB-QoS flow is mapped to a different G-RNTI. In Figure 7 the example of, the first MB-QoS flow (MB-QoS1) is mapped to the first LCID (LCID-1) and the first G-RNTI (G-RNTI 1), the second MB-QoS flow (MB-QoS2) is mapped to the second LCID (LCID-2) and the second G-RNTI (G-RNTI 2), and the third MB-QoS flow (MB-QoS3) is mapped to the third LCID (LCID-3) and the third G-RNTI (G-RNTI3). As further shown, each MB-QoS flow can be associated with a different radio link control (RLC) entity (e.g., different MRBs) for multicast / broadcast communication. In Figure 7 the example of, the first MB-QoS flow (MB-QoS1) is associated with the first RLC entity (RLC 1), the second MB-QoS flow (MB-QoS2) is associated with the second RLC entity (RLC 2), and the third MB-QoS flow (MB-QoS3) is associated with the third RLC entity (RLC 3).

[0061] In a third operation 715, in some aspects, base station 110 can multiplex multiple MB-QoS flows for multicast / broadcast communication using a common MAC protocol data unit (PDU) (e.g., using MRBs). The common MAC PDU can include multiple LCIDs that indicate the corresponding multiple MB-QoS flows for which data is included in the multicast / broadcast transmission associated with the common MAC PDU. For example, the common MAC PDU can include multiple MAC subheaders, each subheader including a different LCID.

[0062] In some aspects, the base station 110 may use a single MAC TB to multiplex multiple MB-QoS flows in a multicast or broadcast transmission. In this case, since each MB-QoS flow is associated with a different G-RNTI, the base station 110 may schedule or transmit the single MAC TB multiple times (e.g., by repeating the same content of the single MAC TB in different time-domain or frequency-domain resources), and may use different G-RNTIs to scramble each MAC TB transmission. For example, G-RNTI 1 may be used to scramble a first MAC TB transmission that includes the content of a single MAC TB and is associated with MB-QoS1, G-RNTI 2 may be used to scramble a second MAC TB transmission that includes the content of a single MAC TB and is associated with MB-QoS2, and G-RNTI 3 may be used to scramble a third MAC TB transmission that includes the content of a single MAC TB and is associated with MB-QoS3. Thus, a single MAC TB may be repeated multiple times, where different G-RNTIs are used to scramble different repetitions. Alternatively, the base station 110 may use different MAC TBs to multiplex multiple MB-QoS flows in a multicast or broadcast transmission, where each MAC TB corresponds to a different LCID and is scrambled using a different G-RNTI.

[0063] In a fourth operation 720, the UE 120 may identify an MB-QoS flow from a multicast or broadcast transmission using a unique G-RNTI corresponding to the MB-QoS flow. For example, when the UE 120 subscribes to an MB-QoS flow, the UE 120 may receive the G-RNTI for that MB-QoS flow. The UE 120 may then use the G-RNTI to descramble the scheduled MBTCH transmission. If such descrambling is successful, the UE 120 may obtain the data of the MB-QoS flow. As shown, the multicast or broadcast transmission may be an initial transmission or a retransmission.

[0064] In the fifth operation 725, the base station 110 may retransmit data of the MB-QoS flow in a unicast transmission. For example, the base station 110 may receive a NACK from the UE 120 or may not receive any ACK / NACK feedback for the data transmission of the MB-QoS flow from the UE 120. In some aspects, this may cause the base station 110 to retransmit the data transmission for the UE 120 in a unicast retransmission. To identify the MB-QoS flows for which data is included in the unicast transmission, the base station 110 may include the LCID for each MB-QoS flow in the MB-QoS flows in the unicast transmission. The base station 110 may scramble the unicast transmission using the C-RNTI for the UE 120. As further shown, the unicast transmission may be associated with an RLC entity (RLCx) different from the multicast / broadcast transmission (e.g., DRB), or may have a different LCID, such as the LCID for the unicast transmission or the DRB. In Figure 7 the example, the base station 110 retransmits the data of MB-QoS1 and MB-QoS3 in a unicast transmission. Thus, the base station 110 includes LCID-1 and LCID-3 in the unicast transmission. If the content (bits) of the MAC TB for the retransmission is different from the content of the MAC TB in the original transmission, HARQ retransmission using soft combining cannot be performed due to the change in the MAC TB content (bits). However, when the original transmission of the MAC TB uses a G-RNTI (such as G-RNTI x) and the retransmission of the same MAC TB (e.g., the same bits or content) uses a different C-RNTI (such as C-RNTI y), the base station 110 may send the original transmission and the retransmission using the same HARQ process and different redundancy versions to allow the UE 120 to perform HARQ combining (soft combining) of the original transmission and the retransmission.

[0065] In a sixth operation 730, the UE 120 may identify the MB-QoS flow from the unicast transmission using the C-RNTI for the UE 120 and the LCID corresponding to the MB-QoS flow. For example, the UE 120 may be configured (e.g., in an RRC message) with a C-RNTI for unicast communication between the UE 120 and the base station 110. The UE 120 may use the C-RNTI to descramble the unicast communication. If such descrambling is successful, the UE 120 may use the LCID associated with the MB-QoS flow to obtain the data of the MB-QoS flow. For example, the LCID may be indicated in the MAC PDU in the unicast transmission. In this case, the unicast LCID-x, the multicast / broadcast LCID-1, and the multicast / broadcast LCID-3 may be multiplexed in the same MAC TB and scrambled using a UE-specific C-RNTI. In some aspects, the base station 110 may retransmit a data transmission to one or more UEs 120 in a multicast or broadcast transmission, in which case those UEs 120 may obtain the data transmission as described above in connection with operation 720. When the unicast LCID-x is multiplexed with the broadcast LCIDs 1 and 3, as shown in this example, due to the change in the MAC TB content, the receiver (e.g., the UE 120) may not be able to perform HARQ combining at the receiver. In some aspects, the base station 110 may retransmit LCID 1 and LCID 3 for the UE 120 in different MAC TBs, each LCID being scrambled using the C-RNTI. In this case, if the original transmission of the MAC TB (in the broadcast or multicast transmission scrambled using the G-RNTI) has the same content as the MAC TB in the unicast retransmission scrambled using the C-RNTI, the receiver (e.g., the UE 120) may perform HARQ combining.

[0066] Using the pattern described in connection with Figure 7 mapping the MB-QoS flow to the LCID and the G-RNTI may allow the UE 120 to receive the MB-QoS flow subscribed to by the UE 120 by using the G-RNTI associated with the MB-QoS flow to descramble the multicast / broadcast communication. In addition, the pattern may use the LCID associated with the MB-QoS flow to implement a unicast retransmission of the initial multicast / broadcast transmission of the MB-QoS flow, thereby improving reliability while saving resources for the UE 120 that successfully receives the initial multicast / broadcast transmission.

[0067] Figure 8 is a diagram illustrating another example of mapping a multicast / broadcast quality of service flow to an LCID in accordance with various aspects of the present disclosure. Figure 8shows a second mode in which each MB-QoS flow in the MB-QoS flow set is mapped to a different logical channel identifier and is mapped to a common G-RNTI for multiple MB-QoS flows. As described above in connection with Figure 6 In some aspects, as described, the base station 110 may indicate to the UE 120 one or more modes for mapping MB-QoS flows to LCIDs and G-RNTIs. In some aspects, the mode described in connection with Figure 8 may be used for a set of switchable MB-QoS flows that are capable of switching between MRBs for multicast or broadcast transmission and DRBs for unicast transmission.

[0068] In a first operation 805, in some aspects, different MB-QoS flows may be mapped to different LCIDs. For example, the base station 110 may configure a one-to-one mapping between MB-QoS flows and LCIDs, as described above in connection with Figure 7 In a second operation 810, different MB-QoS flows may be mapped to a common G-RNTI (the same G-RNTI). For example, the base station 110 may configure a many-to-one mapping between MB-QoS flows and G-RNTIs, where each MB-QoS flow is mapped to the same GRNTI. In the Figure 8 example, a first MB-QoS flow (MB-QoS1) is mapped to a first LCID (LCID-1) and a common G-RNTI, a second MB-QoS flow (MB-QoS2) is mapped to a second LCID (LCID-2) and a common G-RNTI, and a third MB-QoS flow (MB-QoS3) is mapped to a third LCID (LCID-3) and a common G-RNTI. As further shown, each MB-QoS flow may be associated with a different RLC entity for multicast / broadcast communication, as described above in connection with Figure 7 described.

[0069] In a third operation 815, in some aspects, the base station 110 may multiplex multiple MB-QoS flows for multicast / broadcast transmission using a common MAC PDU (e.g., using an MRB). The common MAC PDU may include multiple LCIDs that indicate the corresponding multiple MB-QoS flows, and data for the multiple MB-QoS flows is included in the multicast / broadcast transmission associated with the common MAC PDU. For example, the common MAC PDU may include multiple MAC subheaders, each subheader including a different LCID.

[0070] In some aspects, the base station 110 may multiplex multiple MB-QoS flows in a multicast or broadcast transmission using a single MAC TB. In this case, since each MB-QoS flow is associated with the same G-RNTI, the base station 110 may use a single transmission (instead of multiple transmissions as described above in connection with Figure 7 to schedule or transmit a single MAC TB and may scramble the single MAC TB transmission using the common G-RNTI. Alternatively, the base station 110 may multiplex multiple MB-QoS flows in a multicast or broadcast transmission using different MAC TBs, where each MAC TB corresponds to a different LCID and is scrambled using the common G-RNTI.

[0071] In a fourth operation 820, the UE 120 may identify an MB-QoS flow from a multicast or broadcast transmission (e.g., an initial transmission or a retransmission) using the common G-RNTI for the set of MB-QoS flows and the LCID corresponding to the MB-QoS flow. For example, when the UE 120 subscribes to an MB-QoS flow, the UE 120 may receive the common G-RNTI for the set of MB-QoS flows that includes the MB-QoS flow. Additionally or alternatively, the UE 120 may receive or derive a security key for the MB-QoS flow. The UE 120 may use the common G-RNTI to descramble the scheduled MBTCH communication. If such descrambling is successful, the UE 120 may use the LCID for the MB-QoS flow to obtain the data of the MB-QoS flow. For example, the UE 120 may read the MAC PDU to identify the LCID for the MB-QoS flow (e.g., in the MAC sub-header). In some aspects, different MB-QoS flows may be associated with different security keys such that the UE 120 cannot obtain the data for an MB-QoS flow that the UE 120 has not subscribed to, even though the common G-RNTI for descrambling the communication including the data for the MB-QoS flow has been received.

[0072] In a fifth operation 825, in a similar manner as described above in connection with Figure 7 the base station 110 may retransmit the data of the MB-QoS flow in a unicast transmission. To identify the MB-QoS flow for which the data is included in the unicast transmission, the base station 110 may include the LCID for each of the MB-QoS flows in the MB-QoS flows in the unicast transmission. The base station 110 may scramble the unicast transmission using the C-RNTI for the UE120. As further shown, the unicast transmission may be associated with an RLC entity (RLC x) different from the multicast broadcast transmission (e.g., DRB), or may have a different LCID, such as the LCID for the unicast transmission or the DRB. In Figure 8In the example of, the base station 110 retransmits data for MB-QoS1 and MB-QoS3 in unicast transmission. Thus, the base station 110 includes LCID-1 and LCID-3 in unicast transmission.

[0073] In the sixth operation 830, in a similar manner as described above in conjunction with Figure 7 the UE 120 can use the C-RNTI for the UE120 and use the LCID corresponding to the MB-QoS flow to identify the MB-QoS flow from the unicast transmission. For example, the UE120 can be configured (e.g., in an RRC message) with a C-RNTI for unicast communication between the UE 120 and the base station 110. The UE 120 can use the C-RNTI to descramble the unicast communication. If such descrambling is successful, in a similar manner as described above in conjunction with Figure 7 the UE 120 can use the LCID associated with the MB-QoS flow to obtain the data of the MB-QoS flow. For example, the LCID can be indicated in the MAC PDU in the unicast transmission. When the unicast LCID-x is multiplexed with the broadcast LCIDs 1 and 3, as shown in this example, due to the change in the MAC TB content, the receiver (e.g., the UE 120) may not be able to perform HARQ combining at the receiver. In some aspects, the base station 110 can retransmit LCID 1 and LCID 3 for the UE 120 in different MAC TBs, each LCID being scrambled with the C-RNTI. In this case, if the original transmission of the MAC TB (in a broadcast or multicast transmission scrambled with the G-RNTI) has the same content as the MAC TB in the unicast retransmission scrambled with the C-RNTI, the receiver (e.g., the UE 120) can perform HARQ combining.

[0074] Using the mode described in conjunction with Figure 8 to map the MB-QoS flow to the LCID and G-RNTI can allow the UE 120 to receive the MB-QoS flow subscribed by the UE 120 by using the common G-RNTI associated with the MB-QoS flow to descramble the multicast broadcast communication, and to identify the MB-QoS flow in the descrambled communication by using the LCID. By using a common G-RNTI for multiple MB-QoS flows, UE resources (e.g., processing resources, memory resources, battery power, etc.) can be saved by only requiring a single G-RNTI instead of multiple G-RNTIs for descrambling. In addition, this mode can use the LCID associated with the MB-QoS flow to implement unicast retransmission of the initial multicast broadcast transmission of the MB-QoS flow, thereby improving reliability while saving resources of the UE 120 that successfully receives the initial multicast broadcast transmission.

[0075] Figure 9 FIG. is another example showing the mapping of multicast broadcast service quality flows to LCIDs according to various aspects of the present disclosure. Figure 9 A third mode is shown in which each MB-QoS flow in the MB-QoS flow set is mapped to a different G-RNTI and is mapped to a common LCID for multiple MB-QoS flows. As described above in connection with Figure 6 As described, in some aspects, the base station 110 may indicate to the UE 120 one or more modes for mapping MB-QoS flows to LCIDs and G-RNTIs. In some aspects, the modes described in connection with Figure 9 may be used for a set of switchable MB-QoS flows or a set of non-switchable MB-QoS flows.

[0076] In a first operation 905, in some aspects, different MB-QoS flows may be mapped to a common LCID (the same LCID). For example, the base station 110 may configure a many-to-one mapping between MB-QoS flows and LCIDs, where each MB-QoS flow is mapped to the same LCID. In a second operation 910, different MB-QoS flows may be mapped to different G-RNTIs. For example, the base station 110 may configure a one-to-one mapping between MB-QoS flows and G-RNTIs, where each MB-QoS flow is mapped to a different G-RNTI. In the Figure 9 example, the first MB-QoS flow (MB-QoS1) is mapped to a common LCID (LCID-1) and a first G-RNTI (G-RNTI 1), the second MB-QoS flow (MB-QoS2) is mapped to a common LCID (LCID-1) and a second G-RNTI (G-RNTI 2), and the third MB-QoS flow (MB-QoS3) is mapped to a common LCID (LCID-1) and a third G-RNTI (G-RNTI 3). As further shown, each MB-QoS flow may be associated with a different RLC entity for multicast / broadcast communication, as described above in connection with Figure 7 described.

[0077] In a third operation 915, in some aspects, the base station 110 may multiplex multiple MB-QoS flows for multicast broadcast transmission using a common MAC PDU (e.g., using MRB). In some aspects, the common MAC PDU may include a common LCID for multiple MB-QoS flows, and data for multiple MB-QoS flows is included in the multicast / broadcast transmission associated with the common MAC PDU.

[0078] In some aspects, the base station 110 may multiplex multiple MB-QoS flows in a multicast or broadcast transmission using a single MAC TB. In this case, since each MB-QoS flow is associated with a different G-RNTI, the base station 110 may schedule or transmit the single MAC TB multiple times (e.g., by repeating the same content of the single MAC TB in different time-domain or frequency-domain resources), and may use different G-RNTIs to scramble each MAC TB transmission. For example, G-RNTI 1 may be used to scramble a first MAC TB transmission that includes the content of a single MAC TB and is associated with MB-QoS1, G-RNTI 2 may be used to scramble a second MAC TB transmission that includes the content of a single MAC TB and is associated with MB-QoS2, and G-RNTI 3 may be used to scramble a third MAC TB transmission that includes the content of a single MAC TB and is associated with MB-QoS3. Thus, a single MAC TB may be repeated multiple times, where different G-RNTIs are used to scramble different repetitions. Alternatively, the base station 110 may multiplex multiple MB-QoS flows in a multicast or broadcast transmission using different MAC TBs, where each MAC TB corresponds to the same LCID and is scrambled using a different G-RNTI.

[0079] In a fourth operation 920, the UE 120 may identify the MB-QoS flow from the multicast or broadcast transmission using the unique G-RNTI corresponding to the MB-QoS flow. For example, when the UE 120 subscribes to an MB-QoS flow, the UE 120 may receive the G-RNTI for that MB-QoS flow. The UE 120 may then use the G-RNTI to descramble the scheduled MBTCH communication. If such descrambling is successful, the UE 120 may obtain the data of the MB-QoS flow. As shown, the multicast or broadcast transmission may be an initial transmission or a retransmission.

[0080] In a fifth operation 925, in a manner combined with the above Figure 7In a similar manner as described, the base station 110 may retransmit data of the MB-QoS flow in a unicast transmission. To identify the MB-QoS flow for which its data is included in the unicast transmission, the base station 110 may include, in the unicast transmission, a G-RNTI for each MB-QoS flow in the MB-QoS flow. In some aspects, the base station 110 may also include, in the unicast transmission, the LCID of the MB-QoS flow such that the MB-QoS flow can be identified by a combination of a common LCID and a unique G-RNTI for the MB-QoS flow. The base station 110 may scramble the unicast transmission using the C-RNTI for the UE 120. As further shown, the unicast transmission may be associated with a different RLC entity (RLC x) than the multicast-broadcast transmission (e.g., DRB), or may have a different LCID, such as an LCID for the unicast transmission or the DRB. In Figure 9 the example of, the base station 110 retransmits data for MB-QoS1 and MB-QoS3 in the unicast transmission. Thus, the base station 110 includes, in the unicast transmission, the G-RNTI 1 and the common LCID for identifying MB-QoS1, and the G-RNTI 3 and the common LCID for identifying MB-QoS3. In some aspects, the G-RNTI may be indicated in a MAC PDU (such as a MAC sub-header) in the unicast transmission. When the unicast LCID-x is multiplexed with the broadcast LCIDs 1 and 3, as shown in this example, due to the change in the MAC TB content, the receiver (e.g., UE120) may not be able to perform HARQ combining at the receiver. In some aspects, the base station 110 may retransmit LCID 1 and LCID 3 for the UE 120 in different MAC TBs, each LCID being scrambled using the C-RNTI. In this case, if the original transmission of the MAC TB (in the broadcast or multicast transmission scrambled using the G-RNTI) has the same content as the MAC TB in the unicast retransmission scrambled using the C-RNTI, the receiver (e.g., UE 120) may perform HARQ combining.

[0081] In the sixth operation 930, the UE 120 may identify the MB-QoS flow from the unicast transmission using the C-RNTI for the UE 120, using a common LCID, and using the G-RNTI corresponding to the MB-QoS flow. For example, the UE 120 may be configured (e.g., in an RRC message) with a C-RNTI for unicast communication between the UE 120 and the base station 110. The UE 120 may use the C-RNTI to descramble the unicast communication. If such descrambling is successful, the UE 120 may use the common LCID and the G-RNTI associated with the MB-QoS flow to obtain the data of the MB-QoS flow. For example, the common LCID and the G-RNTI may be indicated in the MAC PDU in the broadcast and / or unicast transmission. In this case, the unicast LCID-x, the multicast broadcast LCID-1, and the multicast broadcast LCID-3 may be multiplexed in the same MAC TB and scrambled using the UE-specific C-RNTI.

[0082] Using the pattern described in conjunction with Figure 9 to map the MB-QoS flow to the LCID and the G-RNTI may allow the UE 120 to receive the MB-QoS flow subscribed to by the UE 120 by using the G-RNTI associated with the MB-QoS flow to descramble the multicast broadcast communication. In addition, this pattern may use the common LCID associated with the MB-QoS flow and the G-RNTI associated with the MB-QoS flow to implement unicast retransmission of the initial multicast broadcast transmission of the MB-QoS flow, thereby improving reliability while saving resources of the UE 120 that successfully receives the initial multicast broadcast transmission. In addition, this pattern may reduce signaling overhead by using a common LCID for a group of MB-QoS flows, thereby requiring fewer LCIDs compared to the case where each MB-QoS flow is associated with a unique LCID.

[0083] Figure 10 is a diagram illustrating another example of mapping a multicast broadcast quality of service flow to an LCID in accordance with various aspects of the present disclosure. Figure 10 shows a fourth pattern in which each MB-QoS flow in a set of MB-QoS flows is mapped to a different identifier (e.g., a different G-RNTI or a different MRB identifier) and is mapped to a fixed LCID for all MB-QoS flows. As described above in conjunction with Figure 6 it is stated that in some aspects, the base station 110 may indicate to the UE 120 one or more patterns for mapping the MB-QoS flow to the LCID and the G-RNTI.

[0084] In some aspects, different MB-QoS flows can be mapped to a fixed LCID (the same LCID) for all MB-QoS flows. In this case, each MB-QoS flow is mapped to the same LCID, which is a fixed LCID reserved for multicast / broadcast communication. In some aspects, different MB-QoS flows can be mapped to different G-RNTIs in a similar manner as described elsewhere herein. Additionally or alternatively, different MB-QoS flows can be mapped to different MRB identifiers (MRBIDs). Figure 10 Four different example MAC PDU subheaders are shown that are used to indicate either the LCID and one of the G-RNTI or MRB ID for an MB-QoS flow.

[0085] Using a fixed LCID and a unique G-RNTI or MRB ID, the transmission and identification of MB-QoS flows can be performed in a similar manner as described above in connection with Figure 9 where a common LCID and a unique G-RNTI were used. However, in the Figure 10 mode, a fixed LCID (which can be used for all MB-QoS flows) can be used instead of a common LCID (which can be used for a set of MB-QoS flows that is a subset of all MB-QoS flows). Additionally, while in some aspects a unique G-RNTI can be used to identify MB-QoS flows, in other aspects, a unique MRB ID can be used to identify MB-QoS flows. When using a unique MRBID, a common G-RNTI can be used for different MB-QoS flows (e.g., all MB-QoS flows). For unicast transmission, either the fixed LCID and one of the G-RNTI or MRB ID can be included in the MAC PDU (e.g., in the MAC PDU subheader), as Figure 10 shown. In some aspects, the fixed LCID can be used to identify MBTCH, and a unique G-RNTI or unique MRB ID can be used to identify the multicast / broadcast service type. By using a fixed LCID, the mode described in connection with Figure 10 can reduce signaling overhead by using the same LCID for all MB-QoS flows, thus requiring fewer LCIDs compared to cases where each MB-QoS flow is associated with a unique LCID or different sets of MB-QoS flows are associated with different LCIDs.

[0086] Figure 11 is a diagram illustrating another example of mapping multicast broadcast quality of service flows to LCIDs in accordance with various aspects of the present disclosure. Figure 11shows the following pattern: In this pattern, each MB-QoS flow in the MB-QoS flow set is mapped to a first LCID and a G-RNTI for multicast or broadcast transmission, and is mapped to a second LCID and a C-RNTI for unicast transmission. As described above in connection with Figure 6 As described, in some aspects, the base station 110 may indicate to the UE 120 one or more patterns for mapping MB-QoS flows to LCIDs and G-RNTIs. Figure 11 shows a proposed enhancement to the NR MAC PDU sub-header (e.g., an enhancement to Section 6.1.2 of 3GPP TS 38.321).

[0087] In a first operation 1105, in some aspects, when the base station 110 configures an MRB (e.g., for an MB-QoS flow), the base station 110 may indicate a first LCID (shown as LCID-A for MB-QoS1) that will be used when data of the MB-QoS flow is transmitted in multicast / broadcast communication (e.g., using the MRB), and a second LCID (shown as LCID-1 for MB-QoS1) that will be used when data of the MB-QoS flow is transmitted in unicast communication (e.g., using a DRB). The base station 110 may also indicate a G-RNTI (shown as G-RNTI1 for MB-QoS1) for multicast / broadcast communication that will be used to obtain (descramble) the MB-QoS flow using the first LCID, and may indicate a C-RNTI that will be used by the UE 120 for unicast communication to obtain (descramble) the MB-QoS flow using the second LCID.

[0088] In some aspects, the base station 110 may indicate (to the UE 120) the first LCID, G-RNTI, second LCID, C-RNTI, or a combination thereof in an RRC message (e.g., a unicast RRC message). In some aspects, the base station 110 may indicate all four of these parameters in the RRC message. In some aspects, the base station 110 may indicate (to the UE 120) the second LCID and C-RNTI in the RRC message, and may indicate the first LCID and G-RNTI using a multicast control channel (e.g., the MBCCH).

[0089] In a second operation 1110, when the base station 110 transmits data of an MB-QoS flow in multicast / broadcast transmission, the base station 110 may use the first LCID. In a third operation 1115, the base station 110 may scramble the multicast / broadcast transmission using the G-RNTI. The UE 120 may use the G-RNTI, the first LCID, or a combination thereof to identify the MB-QoS flow or obtain data of the MB-QoS flow in a manner similar to that described elsewhere herein.

[0090] In a fourth operation 1120, when the base station 110 transmits data for an MB-QoS flow in a unicast transmission, the base station 110 may use a second LCID and may scramble the multicast / broadcast transmission using a C-RNTI. In a fifth operation 1125, the UE 120 may use the C-RNTI and the second LCID to identify the MB-QoS flow or obtain data for the MB-QoS flow in a manner similar to that described elsewhere herein.

[0091] By using different LCIDs for an MB-QoS flow depending on whether the data for the MB-QoS flow is being transmitted in a multicast / broadcast communication or a unicast communication, in combination Figure 11 with the described pattern, signaling overhead can be reduced by reusing the same LCID for multiple MB-QoS flows. For example, the same LCID can be used for different unicast transmissions using different UE-specific C-RNTIs. Additionally, MB-QoS flows associated with different G-RNTIs can use the same LCID while still allowing the UE 120 to distinguish between MB-QoS flows using different G-RNTIs.

[0092] In some aspects, a non-switchable MRB can be reconfigured to be a switchable MRB. A switchable MRB can refer to an MRB that is capable of switching between multicast / broadcast transmissions (e.g., using a G-RNTI) and unicast transmissions (e.g., using a C-RNTI). A non-switchable MRB can refer to an MRB that cannot switch between multicast / broadcast transmissions and unicast transmissions. In some aspects, the base station 110 may configure a non-switchable MRB with a first LCID for multicast / broadcast transmissions. When the base station 110 reconfigures the MRB from non-switchable to switchable, the base station 110 may indicate a second LCID for the MRB for unicast transmissions. The base station 110 may reconfigure the MRB with a cell-unique LCID or may indicate the second LCID in, for example, a multicast broadcast control channel communication (MBCCH), an RRC message (e.g., an RRC reconfiguration message), or a combination thereof. In this way, the base station 110 can increase the flexibility of transmission and retransmission of MB-QoS flows.

[0093] Figure 12 is a diagram illustrating an example process, such as may be performed by a UE, in accordance with various aspects of the present disclosure. The example process is an example of operations performed by a UE (e.g., UE 120) associated with mapping a multicast broadcast quality of service flow to an LCID.

[0094] As Figure 12As shown, in some aspects, the process may include: receiving an indication of a pattern for mapping MB-QoS flows to LCIDs and G-RNTIs (block 1210). For example, a UE (e.g., using the receiving processor 258, the controller / processor 280, the memory 282, or Figure 13 the receiving component 1302, etc.) may receive an indication of a pattern for mapping MB-QoS flows to LCIDs and G-RNTIs, as described above.

[0095] As Figure 12 further shown, in some aspects, the process may include: identifying an MB-QoS flow from the MAC TB at least in part based on the indicated pattern (block 1220). For example, a UE (e.g., using the receiving processor 258, the controller / processor 280, the memory 282, or Figure 13 the identification component 1310, etc.) may identify an MB-QoS flow from the MAC TB at least in part based on the indicated pattern, as described above.

[0096] As Figure 12 further shown, in some aspects, the process may include decoding data included in the MB-QoS flow (block 1230). For example, a UE (e.g., using the receiving processor 258, the controller / processor 280, the memory 282, or Figure 13 the decoding component 1312, etc.) may decode data included in the MB-QoS flow, as described above.

[0097] The process may include additional aspects, such as any single aspect or any combination of aspects described in one or more other processes described below or elsewhere in this document.

[0098] In a first aspect, the pattern includes a pattern in which each MB-QoS flow in a set of MB-QoS flows is mapped to a different logical channel identifier and is mapped to a different G-RNTI.

[0099] In a second aspect, either alone or in combination with the first aspect, the process includes: identifying an MB-QoS flow from a multicast or broadcast transmission at least in part based on a unique G-RNTI corresponding to the MB-QoS flow (e.g., using Figure 13 the identification component 1310).

[0100] In a third aspect, either alone or in combination with one or more of the first and second aspects, one of the following is used to multiplex multiple MB-QoS flows in the multicast or broadcast transmission: a single MAC TB that is transmitted multiple times, where each MAC TB transmission is scrambled using a different G-RNTI, or different MAC TBs corresponding to different logical channel identifiers, where each MAC TB is scrambled using a different G-RNTI.

[0101] In a fourth aspect, either alone or in combination with one or more of the first to third aspects, the process includes: identifying the MB-QoS flow from the unicast transmission (e.g., using the identification component 1310) at least partially based on the C-RNTI for the UE and the unique logical channel identifier corresponding to the MB-QoS flow. Figure 13 of the identification component 1310) identify the MB-QoS flow.

[0102] In a fifth aspect, either alone or in combination with one or more of the first to fourth aspects, the mode includes a mode in which each MB-QoS flow in the MB-QoS flow set is mapped to a different logical channel identifier and is mapped to a common G-RNTI for the multiple MB-QoS flows.

[0103] In a sixth aspect, either alone or in combination with one or more of the first to fifth aspects, the process includes: identifying the MB-QoS flow from the multicast or broadcast transmission (e.g., using the identification component 1310) at least partially based on the logical channel identifier corresponding to the MB-QoS flow. Figure 13 of the identification component 1310) identify the MB-QoS flow.

[0104] In a seventh aspect, either alone or in combination with one or more of the first to sixth aspects, one of the following is used to multiplex multiple MB-QoS flows in the multicast or broadcast transmission: a single MAC TB scrambled using a common G-RNTI, or different MAC TBs corresponding to different logical channel identifiers, where each MAC TB is scrambled using a common G-RNTI.

[0105] In an eighth aspect, either alone or in combination with one or more of the first to seventh aspects, the process includes: identifying the MB-QoS flow from the unicast transmission (e.g., using the identification component 1310) at least partially based on the C-RNTI for the UE and the unique logical channel identifier corresponding to the MB-QoS flow. Figure 13 of the identification component 1310) identify the MB-QoS flow.

[0106] In a ninth aspect, alone or in combination with one or more of the first to eighth aspects, the MB-QoS flow set includes one or more switchable MB-QoS flows that are capable of switching between a multicast broadcast radio bearer for multicast or broadcast transmission and a dedicated radio bearer for unicast transmission.

[0107] In a tenth aspect, alone or in combination with one or more of the first to ninth aspects, the mode includes a mode in which each MB-QoS flow in the MB-QoS flow set is mapped to a different G-RNTI and is mapped to a common logical channel identifier for multiple MB-QoS flows.

[0108] In an eleventh aspect, alone or in combination with one or more of the first to tenth aspects, the process includes: identifying an MB-QoS flow from a multicast or broadcast transmission (e.g., using an identification component 1310) based at least in part on a unique G-RNTI corresponding to the MB-QoS flow. Figure 13

[0109] In a twelfth aspect, alone or in combination with one or more of the first to eleventh aspects, multiple MB-QoS flows are multiplexed in a multicast or broadcast transmission using one of the following: a single MAC TB that is transmitted multiple times, where each MAC TB transmission is scrambled using a different G-RNTI, or different MAC TBs corresponding to a common logical channel identifier, where each MAC TB is scrambled using a different G-RNTI.

[0110] In a thirteenth aspect, alone or in combination with one or more of the first to twelfth aspects, the process includes: identifying an MB-QoS flow from a unicast transmission (e.g., using an identification component 1310) based at least in part on the C-RNTI for the UE, a common logical channel identifier, and a unique G-RNTI corresponding to the MB-QoS flow. Figure 13

[0111] In a fourteenth aspect, alone or in combination with one or more of the first to thirteenth aspects, the MB-QoS flow set includes one or more non-switchable MB-QoS flows that are not capable of switching between a multicast broadcast radio bearer for multicast or broadcast transmission and a dedicated radio bearer for unicast transmission.

[0112] In a fifteenth aspect, alone or in combination with one or more of the first to fourteenth aspects, the MB-QoS flow set includes one or more switchable MB-QoS flows that are capable of switching between a multicast / broadcast radio bearer for multicast or broadcast transmission and a dedicated radio bearer for unicast transmission.

[0113] In a sixteenth aspect, alone or in combination with one or more of the first to fifteenth aspects, the mode includes a mode in which each MB-QoS flow in the MB-QoS flow set is mapped to a fixed logical channel identifier for all MB-QoS flows and is mapped to at least one of a G-RNTI or a multicast / broadcast radio bearer identifier identifying the service type of the MB-QoS flow.

[0114] In a seventeenth aspect, alone or in combination with one or more of the first to sixteenth aspects, the process includes: identifying (e.g., using an identification component 1310) the MB-QoS flow based at least in part on the logical channel identifier and at least one of the following: a G-RNTI, or a multicast / broadcast radio bearer identifier indicated in the MAC PDU sub-header for the MB-QoS flow. Figure 13

[0115] In an eighteenth aspect, alone or in combination with one or more of the first to seventeenth aspects, the mode includes a mode in which each MB-QoS flow in the MB-QoS flow set is mapped to a first logical channel identifier and a G-RNTI for multicast or broadcast transmission and is mapped to a second logical channel identifier associated with the UE and a C-RNTI for unicast transmission.

[0116] In a nineteenth aspect, alone or in combination with one or more of the first to eighteenth aspects, the first logical channel identifier and the G-RNTI are configured using a multicast control channel, and the second logical channel identifier and the C-RNTI are configured in a radio resource control message.

[0117] In a twentieth aspect, alone or in combination with one or more of the first to nineteenth aspects, the first logical channel identifier, the G-RNTI, the second logical channel identifier, and the C-RNTI are configured in a radio resource control message.

[0118] In a twenty - first aspect, either alone or in combination with one or more of the first to twentieth aspects, an MB - QoS flow is associated with a first logical channel identifier and is configured as a non - switchable MB - QoS flow that cannot be switched between a multicast - broadcast radio bearer and a dedicated radio bearer; and the process includes: receiving an instruction for re - configuring the MB - QoS flow as a switchable MB - QoS flow that can be switched between a multicast - broadcast radio bearer and a dedicated radio bearer, where the instruction includes a second logical channel identifier for the MB - QoS flow.

[0119] In a twenty - second aspect, either alone or in combination with one or more of the first to twenty - first aspects, the process includes: receiving an instruction in at least one of a multicast control channel communication or a radio resource control message (e.g., using Figure 13 reception component 1302).

[0120] In a twenty - third aspect, either alone or in combination with one or more of the first to twenty - second aspects, the mode includes at least one of the following: a first mode, where each MB - QoS flow in a first set of MB - QoS flows is mapped to a different logical channel identifier and is mapped to a different G - RNTI; a second mode, where each MB - QoS flow in a second set of MB - QoS flows is mapped to a different logical channel identifier and is mapped to a common G - RNTI for multiple MB - QoS flows; a third mode, where each MB - QoS flow in a third set of MB - QoS flows is mapped to a different G - RNTI and is mapped to a common logical channel identifier for multiple MB - QoS flows; a fourth mode, where each MB - QoS flow in a fourth set of MB - QoS flows is mapped to a fixed logical channel identifier for all MB - QoS flows and is mapped to a G - RNTI that identifies the service type of the MB - QoS flow; a fifth mode, where each MB - QoS flow in a fifth set of MB - QoS flows is mapped to a first logical channel identifier and G - RNTI for multicast or broadcast transmission and is mapped to a second logical channel identifier and C - RNTI associated with the UE for unicast transmission; or a combination thereof.

[0121] In a twenty - fourth aspect, either alone or in combination with one or more of the first to twenty - third aspects, the logical channel identifier corresponds to a multicast - broadcast traffic channel, and the multicast - broadcast traffic channel and the multicast - broadcast control channel are carried in a physical downlink shared channel.

[0122] In a twenty - fifth aspect, either alone or in combination with one or more of the first to twenty - fourth aspects, the process includes: (e.g., using Figure 13The soft combining component 1314) performs soft combining of a first MAC TB of an MB-QoS flow received in a multicast or broadcast transmission scrambled with a G-RNTI and a second MAC TB of the MB-QoS flow received in a unicast transmission scrambled with a cell RNTI.

[0123] In a twenty-sixth aspect, alone or in combination with one or more of the first to twenty-fifth aspects, the process includes: performing soft combining (e.g., using Figure 13 the soft combining component 1314) at least in part based on a determination that the first MAC TB and the second MAC TB carry the same content.

[0124] Figure 13 is a block diagram of an example apparatus 1300 for wireless communication according to various aspects of the present disclosure. The apparatus 1300 may be a UE, or the UE may include the apparatus 1300. In some aspects, the apparatus 1300 includes a receiving component 1302, a communication manager 1304, and a transmitting component 1306, which may communicate with each other (e.g., via one or more buses). As shown, the apparatus 1300 may communicate with another apparatus 1308 (such as a UE, a base station, or another wireless communication device) using the receiving component 1302 and the transmitting component 1306.

[0125] In some aspects, the apparatus 1300 may be configured to perform one or more operations described herein in connection with Figures 6 - 11 Alternatively, the apparatus 1300 may be configured to perform one or more processes described herein, such as Figure 12 the process 1200. In some aspects, the apparatus 1300 may include one or more components of the UE described above in connection with Figure 2 description.

[0126] The receiving component 1302 may receive communications from the apparatus 1308, such as reference signals, control information, data communications, or combinations thereof. The receiving component 1302 may provide the received communications to one or more other components of the apparatus 1300, such as the communication manager 1304. In some aspects, the receiving component 1302 may perform signal processing (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, demapping, equalization, interference cancellation, or decoding, etc.) on the received communications and may provide the processed signals to one or more other components. In some aspects, the receiving component 1302 may include one or more antennas, demodulators, MIMO detectors, receiving processors, controllers / processors, memories, or combinations thereof of the UE described above in connection with Figure 2 description.

[0127] The transmitting component 1306 can send communications to the device 1308, such as reference signals, control information, data communications, or combinations thereof. In some aspects, the communication manager 1304 can generate the communications and can send the generated communications to the transmitting component 1306 for transmission to the device 1308. In some aspects, the transmitting component 1306 can perform signal processing (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or coding, etc.) on the generated communications and can send the processed signal to the device 1308. In some aspects, the transmitting component 1306 can include one or more antennas, a modulator, a transmitting MIMO processor, a transmitting processor, a controller / processor, a memory, or combinations thereof of the UE described above in connection with Figure 2 . In some aspects, the transmitting component 1306 can be co-located with the receiving component 1302 in a transceiver.

[0128] The communication manager 1304 can receive or can cause the receiving component 1302 to receive an indication of a mode for mapping an MB-QoS flow to a logical channel identifier and a G-RNTI. The communication manager 1304 can identify the MB-QoS flow from the MAC TB at least in part based on the indicated mode. The communication manager 1304 can decode the data included in the MB-QoS flow.

[0129] In some aspects, the communication manager 1304 can include a controller / processor, a memory, or combinations thereof of the UE described above in connection with Figure 2 .

[0130] In some aspects, the communication manager 1304 can include a set of components, such as an identification component 1310, a decoding component 1312, a soft combining component 1314, or combinations thereof. Alternatively, the set of components can be separate and distinct from the communication manager 1304. In some aspects, one or more components in the set of components can include a controller / processor, a memory, or combinations thereof of the UE described above in connection with Figure 2 , or can be implemented within the above. Additionally or alternatively, one or more components in the set of components can be at least partially implemented as software stored in a memory. For example, a component (or a part of a component) can be implemented as instructions or code stored in a non-transitory computer-readable medium and executable by a controller or processor to perform the functions or operations of the component.

[0131] In some aspects, the receiving component 1310 may receive an indication of a pattern for mapping an MB-QoS flow to a logical channel identifier and a G-RNTI. The identifying component 1310 may identify an MB-QoS flow from a MAC TB at least in part based on the indicated pattern. The decoding component 1312 may decode data included in the MB-QoS flow.

[0132] In some aspects, the identifying component 1310 may identify an MB-QoS flow from a unicast transmission at least in part based on the C-RNTI for the UE and a unique logical channel identifier corresponding to the MB-QoS flow. In some aspects, the identifying component 1310 may identify an MB-QoS flow from a multicast or broadcast transmission at least in part based on a logical channel identifier corresponding to the MB-QoS flow. In some aspects, the identifying component 1310 may identify an MB-QoS flow from a unicast transmission at least in part based on the C-RNTI for the UE and a unique logical channel identifier corresponding to the MB-QoS flow. In some aspects, the identifying component 1310 may identify an MB-QoS flow from a multicast or broadcast transmission at least in part based on a unique G-RNTI corresponding to the MB-QoS flow. In some aspects, the identifying component 1310 may identify an MB-QoS flow from a unicast transmission at least in part based on the C-RNTI for the UE, a common logical channel identifier, and a unique G-RNTI corresponding to the MB-QoS flow. In some aspects, the identifying component 1310 may identify an MB-QoS flow at least in part based on a logical channel identifier and at least one of the following: a G-RNTI, or a multicast / broadcast radio bearer identifier indicated in the MAC PDU sub-header for the MB-QoS flow.

[0133] In some aspects, the receiving component 1302 may receive an instruction in at least one of a multicast control channel communication or a radio resource control message. In some aspects, the soft combining component 1314 may perform soft combining of a first MAC TB of an MB-QoS flow received in a multicast or broadcast transmission scrambled with a G-RNTI and a second MAC TB of an MB-QoS flow received in a unicast transmission scrambled with a cell RNTI. In some aspects, the soft combining component 1314 may perform soft combining at least in part based on a determination that the first MAC TB and the second MAC TB carry the same content.

[0134] Provide Figure 13 The number and arrangement of the components shown are by way of example. In practice, there may be additional components, fewer components, different components, or components arranged in a different manner compared to Figure 13 the components shown. Additionally, Figure 13The two or more components shown may be implemented within a single component, or Figure 13 the single component shown may be implemented as multiple, distributed components. Additionally or alternatively, Figure 13 a group (one or more) of the components shown may perform one or more functions described as being performed by Figure 13 another group of components shown.

[0135] The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the exact forms disclosed. Modifications and variations may be made in light of the above disclosure, or may be obtained from practice of these aspects.

[0136] As used herein, the term "component" is intended to be broadly interpreted as hardware, firmware, or a combination of hardware and software. As used herein, a processor is implemented as hardware, firmware, or a combination of hardware and software.

[0137] Some aspects are described herein in connection with thresholds. As used herein, meeting a threshold may refer to a value greater than a threshold, greater than or equal to a threshold, less than a threshold, less than or equal to a threshold, equal to a threshold, not equal to a threshold, etc., or a combination thereof.

[0138] It will be apparent that the systems or methods described herein may be implemented in different forms of hardware, firmware, or a combination of hardware and software. The actual special control hardware or software code used to implement these systems or methods is not a limitation of these aspects. Thus, without reference to specific software code, the operation and behavior of the systems or methods are described herein, and it should be understood that the software and hardware can be designed to implement the systems or methods at least in part based on the description herein.

[0139] Even if a particular combination of features is recited in the claims or disclosed in the specification, such combinations are not intended to limit the disclosure of the various aspects. In fact, many of these features may be combined in ways not specifically recited in the claims or disclosed in the specification. Although each dependent claim listed below may directly depend on only one claim, the disclosure of the various aspects includes the combination of each dependent claim with all other claims in the claim set. A phrase referring to "at least one" of a list of items refers to any combination of those items, including a single member. As an example, "at least one of a, b, or c" is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination of multiples of the same elements (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c, or any other ordering of a, b, and c).

[0140] Unless explicitly described, any element, act, or instruction used herein will not be construed as critical or essential. Also, as used herein, the articles "a" and "an" are intended to include one or more items and may be used interchangeably with "one or more." Further, as used herein, the terms "set" and "group" are intended to include one or more items (e.g., related items, unrelated items, combinations of related and unrelated items, etc., or combinations thereof) and may be used interchangeably with "one or more." Where only one item is meant, the phrase "only one" or similar language is used. Further, as used herein, the terms "has," "have," "having," etc. are intended to be open-ended terms. Further, unless otherwise explicitly stated, the phrase "based on" is intended to mean "at least partially based on."

Claims

1. A method of wireless communication performed by a user equipment (UE), comprising: Receiving an indication of a mode that maps each of a set of multiple multicast broadcast (MB) quality of service (QoS) MB-QoS flows to a different group radio network temporary identifier (G-RNTI) and a common logical channel identifier for the set of the multiple MB-QoS flows; Identifying an MB-QoS flow from a medium access control (MAC) transport block (TB) MAC TB according to the indicated mode; And Decoding data included in the MB-QoS flow.

2. The method according to claim 1, wherein, Identifying the MB-QoS flow from the MAC TB according to the indicated mode includes: identifying the MB-QoS flow from a multicast or broadcast transmission according to a unique G-RNTI corresponding to the MB-QoS flow.

3. The method according to claim 1, wherein, The multiple MB-QoS flows are multiplexed in the multicast or broadcast transmission using one of the following: A single MAC TB that is transmitted multiple times, wherein each MAC TB transmission is scrambled using a different G-RNTI, or Different MAC TBs corresponding to different logical channel identifiers, wherein each MAC TB is scrambled using a different G-RNTI.

4. The method according to claim 1, wherein Identifying the MB-QoS flow from the MAC TB according to the indicated mode includes: identifying the MB-QoS flow from a unicast transmission according to a cell RNTI (C-RNTI), the common logical channel identifier, and a unique G-RNTI corresponding to the MB-QoS flow.

5. The method according to claim 1, wherein, The set of the multiple MB-QoS flows includes one or more non-switchable MB-QoS flows that cannot be switched between a multicast broadcast radio bearer for multicast or broadcast transmission and a dedicated radio bearer for unicast transmission.

6. The method according to claim 1, wherein, The set of the multiple MB-QoS flows includes one or more switchable MB-QoS flows that can be switched between a multicast broadcast radio bearer for multicast or broadcast transmission and a dedicated radio bearer for unicast transmission.

7. The method according to claim 1, further comprising: Receiving a second indication of a second mode, in which each MB-QoS flow in a second set of multiple MB-QoS flows is mapped to a fixed logical channel identifier for all MB-QoS flows and is mapped to a multicast broadcast radio bearer identifier that is used to identify a service type of the corresponding MB-QoS flow in the second set of the multiple MB-QoS flows.

8. The method according to claim 1, further comprising: Identifying the MB-QoS flow according to at least one of a logical channel identifier and a G-RNTI or a multicast broadcast radio bearer identifier indicated in a MAC protocol data unit (PDU) sub-header for the MB-QoS flow.

9. The method according to claim 1, wherein The MB-QoS flow is associated with a first logical channel identifier and is configured as a non-switchable MB-QoS flow that cannot be switched between a multicast broadcast radio bearer and a dedicated radio bearer; And The method further includes: receiving an instruction for reconfiguring the MB-QoS flow into a switchable MB-QoS flow capable of being switched between the multicast broadcast radio bearer and the dedicated radio bearer, where the instruction includes a second logical channel identifier for the MB-QoS flow.

10. The method according to claim 9 further comprises: The instruction is received in at least one of a multicast control channel communication or a radio resource control message.

11. The method according to claim 1, wherein, The logical channel identifier corresponds to a multicast broadcast traffic channel, and wherein the multicast broadcast traffic channel and the multicast broadcast control channel are carried in a physical downlink shared channel.

12. The method according to claim 1 further comprises: Perform soft combining of a first MAC TB of the MB-QoS flow received in a multicast or broadcast transmission scrambled with a G-RNTI and a second MAC TB of the MB-QoS flow received in a unicast transmission scrambled with a cell RNTI.

13. The method according to claim 12 further comprises: The soft combining is performed at least partially based on a determination that the first MAC TB and the second MAC TB carry the same content.

14. A user equipment (UE) for wireless communication, comprising: A memory; And One or more processors coupled to the memory, the one or more processors being configured to cause the UE to perform the following operations: Receive an indication of a mode that maps each MB-QoS flow in a set of multiple multicast broadcast (MB) quality of service (QoS) MB-QoS flows to a different group radio network temporary identifier (G-RNTI) and a common logical channel identifier for the set of multiple MB-QoS flows; Identify the MB-QoS flow from a media access control (MAC) transport block (TB) MAC TB according to the indicated mode; And Decode data included in the MB-QoS flow.

15. The UE according to claim 14, wherein To identify the MB-QoS flow from the MAC TB according to the indicated mode, the one or more processors are configured to cause the UE to perform the following operations: identify the MB-QoS flow from a multicast or broadcast transmission according to a unique G-RNTI corresponding to the MB-QoS flow.

16. The UE according to claim 14, wherein, The multiple MB-QoS flows are multiplexed in the multicast or broadcast transmission using one of the following: A single MAC TB transmitted multiple times, where each MAC TB transmission is scrambled with a different G-RNTI, or Different MAC TBs corresponding to different logical channel identifiers, where each MAC TB is scrambled with a different G-RNTI.

17. The UE according to claim 14, wherein, To identify the MB-QoS flow from the MAC TB according to the indicated mode, the one or more processors are configured to cause the UE to perform the following operations: identify the MB-QoS flow from the unicast transmission according to the cell RNTI (C-RNTI), the common logical channel identifier, and the unique G-RNTI corresponding to the MB-QoS flow.

18. The UE according to claim 14, wherein, The set of the multiple MB-QoS flows includes one or more non-switchable MB-QoS flows that cannot be switched between the multicast broadcast radio bearer for multicast or broadcast transmission and the dedicated radio bearer for unicast transmission.

19. The UE according to claim 14, wherein, The set of the multiple MB-QoS flows includes one or more switchable MB-QoS flows that can be switched between the multicast broadcast radio bearer for multicast or broadcast transmission and the dedicated radio bearer for unicast transmission.

20. The UE according to claim 14, wherein, The one or more processors are further configured to: receive a second indication of a second mode, in which each MB-QoS flow in a second set of multiple MB-QoS flows is mapped to a fixed logical channel identifier for all MB-QoS flows and is mapped to a multicast broadcast radio bearer identifier that is used to identify the service type of the corresponding MB-QoS flow in the second set of multiple MB-QoS flows.

21. The UE according to claim 14, wherein The one or more processors are further configured to: identify the MB-QoS flow according to at least one of the logical channel identifier and the G-RNTI or the multicast broadcast radio bearer identifier indicated in the MAC protocol data unit (PDU) sub-header for the MB-QoS flow.

22. The UE according to claim 14, wherein, The MB-QoS flow is associated with a first logical channel identifier and is configured as a non-switchable MB-QoS flow that cannot be switched between the multicast broadcast radio bearer and the dedicated radio bearer; and wherein the one or more processors are further configured to: receive an instruction to reconfigure the MB-QoS flow as a switchable MB-QoS flow that can be switched between the multicast broadcast radio bearer and the dedicated radio bearer, wherein the instruction includes a second logical channel identifier for the MB-QoS flow.

23. The UE according to claim 22, wherein, The one or more processors are further configured to: receive the instruction in at least one of the multicast control channel communication or the radio resource control message.

24. The UE according to claim 14, wherein The logical channel identifier corresponds to the multicast broadcast traffic channel, and wherein the multicast broadcast traffic channel and the multicast broadcast control channel are carried in the physical downlink shared channel.

25. The UE according to claim 14, wherein, The one or more processors are further configured to: perform soft combining of a first MAC TB of the MB-QoS flow received in the multicast or broadcast transmission scrambled with the G-RNTI and a second MAC TB of the MB-QoS flow received in the unicast transmission scrambled with the cell RNTI.

26. The UE according to claim 25, wherein The one or more processors are further configured to perform the soft combination based at least in part on a determination that the first MAC TB and the second MAC TB carry the same content.

27. A non-transitory computer-readable medium storing one or more instructions for wireless communication, the one or more instructions, when executed by one or more processors of a user equipment (UE), cause the UE to: Receive an indication of a mode that maps each of a plurality of multicast broadcast (MB) quality of service (QoS) MB-QoS flows in a set of MB-QoS flows to a different group radio network temporary identifier (G-RNTI) and a common logical channel identifier for the set of the plurality of MB-QoS flows; Identify an MB-QoS flow from a media access control (MAC) transport block (TB) MAC TB according to the indicated mode; And Decode data included in the MB-QoS flow.

28. An apparatus for wireless communication, comprising: Means for receiving an indication of a mode that maps each of a plurality of multicast broadcast (MB) quality of service (QoS) MB-QoS flows in a set of MB-QoS flows to a different group radio network temporary identifier (G-RNTI) and a common logical channel identifier for the set of the plurality of MB-QoS flows; Means for identifying an MB-QoS flow from a media access control (MAC) transport block (TB) MAC TB according to the indicated mode; And Means for decoding data included in the MB-QoS flow.

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