Method and apparatus for radio resource control (RRC) state selection for multicast service reception

Abstract

The present disclosure provides systems, apparatus, methods, and computer-readable media for supporting radio resource control (RRC) state selection for multicast service reception. A user equipment (UE) may subscribe to multicast services when in an RRC connected state, and may thereafter transition to an RRC inactive state. The network entity may then send an indication of whether the UE will remain in the RRC inactive state to receive a multicast transmission associated with the multicast service or whether the UE will transition to the RRC connected state to receive the multicast transmission. In some aspects, the indication may cause some UEs to remain in an RRC inactive state to receive a multicast transmission (which may reduce power consumption), while other UEs may transition to an RRC connected state to receive the same multicast transmission (which may improve communication reliability). Other aspects and features are also claimed and described.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Greek Patent Application No. 20220100592, filed on July 25, 2022, entitled “RADIO RESOURCE CONTROL (RRC) STATE SELECTION FOR MULTICAST SERVICE RECEPTION,” which is expressly incorporated herein by reference in its entirety. Technical Field

[0003] Aspects of the present disclosure relate generally to wireless communication systems, and more particularly, to radio resource control (RRC) state selection for multicast service reception in wireless communication systems. Background Art

[0004] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, broadcast, and the like. Wireless multiple access communication systems may include multiple base stations or network access nodes, each of which simultaneously supports communication with multiple communication devices (which may be referred to as user equipment (UE) in other aspects). These systems may be able to support communication with multiple UEs by sharing available system resources (such as time, frequency, and power). Examples of such multiple access systems include fourth generation (4G) systems (such as long term evolution (LTE) systems, advanced LTE (LTE-A) systems, or LTE-A Pro systems) and fifth generation (5G) systems (which may be referred to as new radio (NR) systems). These systems may employ techniques such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal frequency division multiple access (OFDMA), or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM).

[0005] Some wireless communication systems use multicast services to improve performance. For example, by sending the same data to multiple UEs via multicast transmission, this can reduce the use of radio resources compared to sending data to the UEs individually. Therefore, the availability of radio resources for other devices or other applications can be increased. However, in some cases, the UE may not correctly receive or decode the multicast transmission. For example, noise or interference that may exist in the wireless communication system may cause the UE to incorrectly receive or decode the multicast transmission. In some cases, the UE can request a retransmission of the multicast transmission, such as by sending a negative acknowledgment (NACK) associated with the multicast transmission to initiate a retransmission. In some other cases, the UE may not be able to request a retransmission. For example, in some cases, the UE may not be able to access the uplink control channel to send a NACK, such as when the UE is in a radio resource control (RRC) inactive state. Therefore, if the UE fails to correctly receive or decode the multicast transmission when operating in the RRC inactive state, the UE may not be able to initiate a retransmission of the multicast transmission, and therefore, the UE may experience reduced communication reliability associated with the multicast service. Therefore, some wireless communication protocols may ensure or require that the UE is in a connected state to receive the multicast transmission. However, such techniques may be associated with increased power consumption by the UE, which may be undesirable or impractical in some applications. Summary of the Invention

[0006] The following summarizes some aspects of the present disclosure to provide a basic understanding of the technology discussed. This summary is not an extensive overview of all anticipated features of the present disclosure and is neither intended to identify key or important elements of all aspects of the present disclosure nor to delineate the scope of any or all aspects of the present disclosure. The sole purpose of this summary is to present some concepts of one or more aspects of the present disclosure in a summarized form as a prelude to the more detailed embodiments that will be presented later.

[0007] One innovative aspect of the subject matter described in the present disclosure can be implemented in a method for wireless communication performed by a user equipment (UE). The method includes subscribing to a multicast service while operating in a radio resource control (RRC) connected state and transitioning from the RRC connected state to an RRC inactive state. The method also includes receiving a paging message associated with the multicast service while operating in the RRC inactive state. The paging message includes an indication of whether the UE will remain in the RRC inactive state or transition from the RRC inactive state to the RRC connected state. The method also includes receiving a multicast transmission associated with the multicast service while operating in one of the RRC inactive state or the RRC connected state. The one of the RRC inactive state or the RRC connected state is based on the indication.

[0008] Another innovative aspect of the subject matter described in the present disclosure can be implemented in a UE. The UE includes at least one processor and a memory coupled to the at least one processor and storing processor-readable instructions, which, when executed by the at least one processor, are configured to subscribe to a multicast service and transition from the RRC connected state to an RRC inactive state when operating in an RRC connected state. The at least one processor is further configured to receive a paging message associated with the multicast service when operating in the RRC inactive state. The paging message includes an indication of whether the UE will remain in the RRC inactive state or will transition from the RRC inactive state to the RRC connected state. The at least one processor is further configured to receive a multicast transmission associated with the multicast service when operating in one of the RRC inactive state or the RRC connected state. The one of the RRC inactive state or the RRC connected state is based on the indication.

[0009] Another innovative aspect of the subject matter described in the present disclosure can be implemented in a method for wireless communication performed by a base station. The method includes receiving a subscription message associated with a multicast service when a UE is operating in an RRC connected state. The method also includes sending a paging message associated with the multicast service when the UE is operating in an RRC inactive state. The paging message includes an indication of whether the UE will remain in the RRC inactive state or will transition from the RRC inactive state to the RRC connected state. The method also includes sending a multicast transmission associated with the multicast service when the UE is operating in one of the RRC inactive state or the RRC connected state. The one of the RRC inactive state or the RRC connected state is based on the indication.

[0010] Another innovative aspect of the subject matter described in the present disclosure can be implemented in a base station. The base station includes at least one processor and a memory coupled to the at least one processor and storing processor-readable code, which, when executed by the at least one processor, is configured to receive a subscription message associated with a multicast service when the UE is operating in an RRC connected state. The at least one processor is further configured to send a paging message associated with the multicast service when the UE is operating in an RRC inactive state. The paging message includes an indication of whether the UE will remain in the RRC inactive state or will transition from the RRC inactive state to the RRC connected state. The at least one processor is further configured to send a multicast transmission associated with the multicast service when the UE is operating in one of the RRC inactive state or the RRC connected state. The one of the RRC inactive state or the RRC connected state is based on the indication.

[0011] When reading the following description of the specific example implementation of the present disclosure in conjunction with the accompanying drawings, other aspects, features and specific implementations of the present disclosure will become apparent to those of ordinary skill in the art. Although the features of the present disclosure can be described with respect to the specific specific implementations and the accompanying drawings below, all specific implementations of the present disclosure can include one or more advantageous features in the advantageous features described herein. In other words, although one or more specific implementations can be described as having specific advantageous features, one or more of such features can also be used according to the various specific implementations of the present disclosure described herein. In a similar manner, although example specific implementations may be described below as device, system or method specific implementations, such example specific implementations can be implemented in various devices, systems and methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] A further understanding of the nature and advantages of the present disclosure may be achieved by referring to the following drawings. In the drawings, similar components or features may have the same reference number. In addition, various components of the same type may be distinguished by following the reference number with a dash and a second reference number to distinguish between similar components. If only the first reference number is used in the specification, the description applies to any of the similar components having the same first reference number, regardless of the second reference number.

[0013] Figure 1 is a block diagram illustrating details of an example wireless communication system in accordance with one or more aspects.

[0014] Figure 2 is a block diagram illustrating an example of a base station and a user equipment (UE) according to one or more aspects.

[0015] Figure 3 is a block diagram illustrating an example wireless communication system that supports radio resource control (RRC) state selection for multicast service reception in accordance with one or more aspects.

[0016] Figure 4 is a flow diagram illustrating an example process for supporting RRC state selection for multicast service reception in accordance with one or more aspects.

[0017] Figure 5 is a flow diagram illustrating an example process for supporting RRC state selection for multicast service reception in accordance with one or more aspects.

[0018] Figure 6 is a block diagram of an example UE supporting RRC state selection for multicast service reception according to one or more aspects.

[0019] Figure 7is a block diagram of an example base station supporting RRC state selection for multicast service reception according to one or more aspects.

[0020] The same reference numbers and designations in different drawings indicate similar elements. DETAILED DESCRIPTION

[0021] The various aspects of the present disclosure are described more fully below with reference to the accompanying drawings. However, the present disclosure can be embodied in many different forms and should not be interpreted as being limited to any specific structure or function given throughout the present disclosure. On the contrary, these aspects are provided so that the present disclosure will be thorough and complete, and the scope of the present disclosure will be fully conveyed to those skilled in the art. Based on the teachings herein, it will be understood by those skilled in the art that the scope of the present disclosure is intended to cover any aspect of the disclosure disclosed herein, whether that aspect is implemented independently of any other aspect of the disclosure or implemented in combination with any other aspect of the disclosure. For example, any amount of aspects set forth herein can be used to implement a device or practice method. In addition, the scope of the present disclosure is intended to cover such devices or methods implemented using other structures, functionality, or structure and functionality in addition to or different from the various aspects of the disclosure set forth herein. Any aspect of the present disclosure disclosed herein may be embodied by one or more elements of a claim.

[0022] The present disclosure provides systems, devices, methods and computer-readable media that support radio resource control (RRC) state selection for multicast service reception. A user equipment (UE) can subscribe to (or "join") a multicast service when in an RRC connected state. After subscribing to the multicast service, the UE can transition from the RRC connected state to an RRC inactive state. Subsequently, a network entity can send an indication to the UE as to whether the UE will remain in the RRC inactive state to receive multicast transmissions associated with the multicast service or whether the UE will transition to the RRC connected state to receive the multicast transmissions. In some examples, the indication may be included in a paging message that notifies the UE subscribed to the multicast service of the multicast transmission. In some examples, the indication may specify that a UE associated with a first priority will remain in the RRC inactive state to receive the multicast transmission. Additionally or alternatively, the indication may specify that a UE associated with a second priority higher than the first priority will transition to the RRC connected state to receive the multicast transmission. In some such examples, UEs associated with the second priority may be associated with an ultra-reliable, low-latency communication (URLLC) application type, and UEs associated with the first priority may be associated with another application type.

[0023] Specific implementations of the subject matter described in this disclosure may be implemented to achieve one or more of the following potential advantages. In some aspects, the techniques of this disclosure may reduce power consumption while improving communication reliability by supporting selection of an RRC state for multicast service reception. For example, some UEs may remain in an RRC inactive state to receive a multicast transmission (which may reduce power consumption), while other UEs may transition to an RRC connected state to receive the same multicast transmission (which may improve communication reliability associated with reception of the multicast transmission). Thus, performance associated with a multicast service may be improved by reducing power consumption of one or more UEs while improving communication reliability of one or more other UEs.

[0024] In various implementations, the techniques and apparatus may be used in wireless communication networks, such as code division multiple access (CDMA) networks, time division multiple access (TDMA) networks, frequency division multiple access (FDMA) networks, orthogonal FDMA (OFDMA) networks, single carrier FDMA (SC-FDMA) networks, LTE networks, GSM networks, fifth generation (5G) or new radio (NR) networks (sometimes referred to as "5G NR" networks, systems, or devices), and other communication networks. As described herein, the terms "network" and "system" can be used interchangeably. In some implementations, two or more wireless communication systems (also referred to as wireless communication networks) may be configured to provide or participate in authorized shared access between the two or more wireless communication systems.

[0025] A CDMA network may implement a radio technology such as Universal Terrestrial Radio Access (UTRA), cdma2000, etc. UTRA includes Wideband CDMA (W-CDMA) and Low Chip Rate (LCR). CDMA2000 covers IS-2000, IS-95, and IS-856 standards.

[0026] TDMA networks can implement radio technologies such as Global System for Mobile Communications (GSM). 3GPP defines standards for the GSM Evolution (Enhanced Data Rates for GSM Evolution) Radio Access Network (RAN), also referred to as GERAN. GERAN is the radio component of GSM or GSM EDGE, along with the network that combines base stations (e.g., Ater and Abis interfaces, etc.) and base station controllers (e.g., interfaces, etc.). The radio access network represents the component of a GSM network through which phone calls and packet data are routed from the public switched telephone network (PSTN) and the internet to subscriber handsets (also known as user terminals or user equipment (UE)), and vice versa. A mobile phone operator's network may include one or more GERANs, which, in the case of UMTS / GSM networks, may be coupled to the UTRAN. Additionally, an operator's network may include one or more LTE networks, or one or more other networks. Various network types may use different radio access technologies (RATs) and radio access networks (RANs).

[0027] OFDMA networks can implement radio technologies such as Evolved UTRA (E-UTRA), IEEE 802.11, IEEE 802.16, IEEE802.20, Flash OFDM, etc. UTRA, E-UTRA, and GSM are part of the Universal Mobile Telecommunications System (UMTS). Specifically, Long Term Evolution (LTE) is a version of UMTS that uses E-UTRA. UTRA, E-UTRA, GSM, UMTS, and LTE are described in documents provided by an organization called the "3rd Generation Partnership Project" (3GPP), while cdma2000 is described in documents from an organization called the "3rd Generation Partnership Project 2" (3GPP2). These various radio technologies and standards are known or under development. For example, 3GPP is a collaboration between telecommunications association groups to define globally applicable third-generation (3G) mobile phone specifications. 3GPP Long Term Evolution (LTE) is a 3GPP initiative aimed at improving the Universal Mobile Telecommunications System (UMTS) mobile phone standard. 3GPP can define specifications for next-generation mobile networks, mobile systems, and mobile devices. This disclosure may describe certain aspects with reference to LTE, 4G, 5G, or NR technologies; however, the description is not intended to be limited to a particular technology or application, and one or more aspects described with reference to one technology may be understood to be applicable to another technology. Indeed, one or more aspects of this disclosure relate to shared access to wireless spectrum between networks using different radio access technologies or radio air interfaces.

[0028] 5G networks are expected to have diverse deployments, diverse spectrum, and diverse services and devices that can be implemented using a unified air interface based on OFDM. To achieve these goals, in addition to developing new radio technologies for 5G NR networks, further enhancements to LTE and LTE-A are also being considered. 5G NR will be able to scale to (1) networks with ultra-high density (e.g., approximately 1M nodes / km) 2 (1) provide coverage for the massive Internet of Things (IoT) with ultra-low complexity (e.g., on the order of tens of bits per second), ultra-low energy (e.g., on the order of 10+ years battery life), and deep coverage with the ability to reach challenging locations; (2) include mission-critical control with strong security to protect sensitive personal, financial, or classified information, ultra-high reliability (e.g., on the order of 99.9999% reliability), ultra-low latency (e.g., on the order of 1 millisecond (ms)), and users with a wide range of mobility or lack of mobility; and (3) provide coverage with enhanced mobile broadband (including very high capacity (e.g., on the order of 10 Tbps / km 2 ), coverage of extremely high data rates (such as multi-Gbps rates, 100+Mbps user experience rates), and deep awareness with advanced discovery and optimization.

[0029] 5G NR devices, networks, and systems can be implemented using optimized OFDM-based waveform features. These features may include scalable parameter sets and transmit time intervals (TTIs); a common flexible framework that leverages dynamic, low-latency time division duplex (TDD) or frequency division duplex (FDD) designs to efficiently multiplex services and features; and advanced wireless technologies such as massive multiple-input multiple-output (MIMO), robust millimeter wave (mmWave) transmission, advanced channel coding, and device-centric mobility. The scalability of parameter sets and the scaling of subcarrier spacing in 5G NR can effectively address the operation of various services across different spectrums and deployments. For example, in various outdoor and macro coverage deployments with less than 3 GHz FDD or TDD implementations, subcarrier spacing may occur at 15 kHz, for example, over bandwidths of 1 MHz, 5 MHz, 10 MHz, 20 MHz, etc. For various other outdoor and small cell coverage deployments with TDD greater than 3 GHz, subcarrier spacing may occur at 30 kHz over 80 MHz or 100 MHz bandwidths. For various other indoor broadband implementations, using TDD in the unlicensed portion of the 5 GHz band, the subcarrier spacing may occur at 60 kHz over a 160 MHz bandwidth. Finally, for various deployments transmitting over mmWave components using TDD at 28 GHz, the subcarrier spacing may occur at 120 kHz over a 500 MHz bandwidth.

[0030] 5G NR's scalable parameter set facilitates scalable TTIs for diverse latency and quality of service (QoS) requirements. For example, shorter TTIs can be used for low latency and high reliability, while longer TTIs can be used for higher spectral efficiency. Efficient multiplexing of long and short TTIs allows transmission to start on symbol boundaries. 5G NR also anticipates a self-contained integrated subframe design, where uplink or downlink scheduling information, data, and acknowledgments are in the same subframe. The self-contained integrated subframe supports communications in unlicensed or contention-based shared spectrum, and adaptive uplink or downlink can be flexibly configured on a per-cell basis to dynamically switch between uplink and downlink to meet current traffic needs.

[0031] For clarity, certain aspects of the devices and techniques may be described below with reference to example 5G NR implementations or in a 5G-centric manner, and 5G terminology may be used as illustrative examples in portions of the description below; however, the description is not intended to be limited to 5G applications.

[0032] Furthermore, it should be understood that in operation, a wireless communication network adapted according to the concepts herein can operate using any combination of licensed or unlicensed spectrum, depending on load and availability. Therefore, it will be apparent to one of ordinary skill in the art that the systems, apparatus, and methods described herein can be applied to other communication systems and applications beyond the specific examples provided.

[0033] Figure 1 1 is a block diagram illustrating details of an example wireless communication system. The wireless communication system may include a wireless network 100. For example, the wireless network 100 may include a 5G wireless network. As will be appreciated by those skilled in the art, Figure 1 The components appearing in may have related counterparts in other network arrangements, including, for example, cellular network arrangements and non-cellular network arrangements (such as device-to-device, ad-hoc, or ad-hoc network arrangements, etc.).

[0034] Figure 1The illustrated wireless network 100 includes multiple base stations 105 and other network entities. A base station can be a station that communicates with a UE and can be referred to as an evolved Node B (eNB), next-generation eNB (gNB), access point, etc. Each base station 105 can provide communication coverage for a specific geographic area. In 3GPP, the term "cell" can refer to the specific geographic coverage area of ​​a base station or a base station subsystem serving that coverage area, depending on the context in which the term is used. In specific implementations of wireless network 100 herein, base stations 105 can be associated with the same operator or different operators, such as when wireless network 100 may include multiple operator wireless networks. In specific implementations of wireless network 100 herein, base stations 105 can provide wireless communications using one or more of the same frequencies as neighboring cells (e.g., one or more frequency bands in a licensed spectrum, an unlicensed spectrum, or a combination thereof). In some examples, an individual base station 105 or UE 115 can be operated by more than one network operating entity. In some other examples, each base station 105 and UE 115 can be operated by a single network operating entity.

[0035] A base station may provide communication coverage for a macro cell or a small cell (such as a pico cell or femto cell) or other type of cell. A macro cell generally covers a relatively large geographic area (such as a radius of several kilometers) and may allow unrestricted access by UEs that have a service subscription with a network provider. A small cell (such as a pico cell) will generally cover a relatively small geographic area and may allow unrestricted access by UEs that have a service subscription with a network provider. A small cell (such as a femto cell) will also generally cover a relatively small geographic area (such as a residence) and, in addition to unrestricted access, may also provide restricted access to UEs associated with the femto cell (such as UEs in a closed subscriber group (CSG), UEs of users in the residence, and so on). A base station for a macro cell may be referred to as a macro base station. A base station for a small cell may be referred to as a small cell base station, a pico base station, a femto base station, or a home base station. In Figure 1 In the example shown in FIG, base stations 105d and 105e are conventional macro base stations, while base stations 105a-105c are macro base stations enabled with one of 3D, Full Dimension (FD), or Massive MIMO. Base stations 105a-105c utilize their higher-dimensional MIMO capabilities to increase coverage and capacity using 3D beamforming in both elevation and azimuth beamforming. Base station 105f is a small cell base station, which can be a home node or a portable access point. The base station can support one or more cells, such as two cells, three cells, four cells, and so on.

[0036] Wireless network 100 may support synchronous or asynchronous operation. For synchronous operation, base stations may have similar frame timings, and transmissions from different base stations may be approximately aligned in time. For asynchronous operation, base stations may have different frame timings, and transmissions from different base stations may not be aligned in time. In some cases, the network may be enabled or configured to handle dynamic switching between synchronous and asynchronous operation.

[0037] UEs 115 are dispersed throughout wireless network 100, and each UE may be stationary or mobile. It should be understood that although mobile devices are generally referred to as user equipment (UE) in the standards and specifications promulgated by 3GPP, such devices may be additionally or alternatively referred to by those skilled in the art as mobile stations (MS), subscriber stations, mobile units, subscriber units, wireless units, remote units, mobile devices, wireless devices, wireless communication devices, remote devices, mobile subscriber stations, access terminals (ATs), mobile terminals, wireless terminals, remote terminals, handsets, terminals, user agents, mobile clients, clients, or some other suitable terminology. In this document, a "mobile" device or UE does not necessarily have the ability to be mobile and may be stationary. Some non-limiting examples of mobile devices, such as those that may include specific implementations of one or more of UEs 115, include mobile stations, cellular (mobile) phones, smartphones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, laptops, personal computers (PCs), notebooks, netbooks, smartbooks, tablets, and personal digital assistants (PDAs). The mobile device may also be an "Internet of Things" (IoT) or "Internet of Everything" (IoE) device, such as a car or other transportation vehicle, a satellite radio, a global positioning system (GPS) device, a global navigation satellite system (GNSS) device, a logistics controller, a drone, a multi-rotor helicopter, a quadcopter, smart energy or security equipment, solar panels or solar arrays, urban lighting, tap water or other infrastructure; industrial automation and enterprise equipment; consumer and wearable devices, such as glasses, wearable cameras, smart watches, health or fitness trackers, mammalian implantable devices, gesture tracking devices, medical devices, digital audio players (such as MP3 players), cameras or game consoles; and digital home or smart home devices, such as home audio, video and multimedia devices, appliances, sensors, vending machines, smart lighting, home security systems or smart meters. In one aspect, the UE may be a device that includes a universal integrated circuit card (UICC). In another aspect, the UE may be a device that does not include a UICC. In some aspects, a UE that does not include a UICC may be referred to as an IoE device. Figure 1The UEs 115a-115d of the illustrated implementation are examples of mobile smartphone-type devices accessing the wireless network 100. A UE may be a machine specifically configured for connected communications, including machine type communications (MTC), enhanced MTC (eMTC), narrowband IoT (NB-IoT), etc. Figure 1 The illustrated UEs 115e-115k are examples of various machines configured for communication accessing the 5G network 100.

[0038] A mobile device, such as UE 115, may be able to communicate with any type of base station, whether macro, pico, femto, relay, etc. Figure 1 In the figure, communication links (represented as lightning bolts) indicate wireless transmissions between a UE and a serving base station (a serving base station is a base station designated to serve the UE on a downlink or uplink), or desired transmissions between base stations, and backhaul transmissions between base stations. Backhaul communications between base stations in wireless network 100 can occur using wired or wireless communication links.

[0039] In operation of the 5G network 100, base stations 105a-105c use 3D beamforming and coordinated spatial techniques, such as coordinated multipoint (CoMP) or multi-connectivity, to serve UEs 115a and 115b. Macro base station 105d performs backhaul communications with base stations 105a-105c and small cell base station 105f. Macro base station 105d also transmits multicast services that are subscribed to and received by UEs 115c and 115d. Such multicast services may include mobile TV or streaming video, or may include other services for providing community information, such as weather emergencies or alerts, such as Amber alerts or gray alerts.

[0040] The wireless network 100 of a specific implementation supports mission-critical communications with ultra-reliable and redundant links for mission-critical devices (e.g., UE 115e, which is a drone). The redundant communication links with UE 115e include those from macro base stations 105d and 105e, as well as small cell base station 105f. Other machine-type devices (such as UE 115f (thermometer), UE 115g (smart meter), and UE 115h (wearable device)) can communicate directly with base stations (such as small cell base station 105f and macro base station 105e) over the wireless network 100, or communicate through the wireless network in a multi-hop configuration by communicating with another user equipment that relays its information to the network (such as UE 115f communicating temperature measurement information to smart meter UE 115g, which is reported to the network via small cell base station 105f). The 5G network 100 may provide additional network efficiency through dynamic, low-latency TDD or FDD communications, such as in a vehicle-to-vehicle (V2V) mesh network between UEs 115i-115k communicating with a macro base station 105e.

[0041] Figure 2 is a block diagram conceptually illustrating an example design of a base station 105 and a UE 115. The base station 105 and the UE 115 may be Figure 1 For a restricted association scenario (as mentioned above), the base station 105 may be Figure 1 The small cell base station 105f in the example, and the UE 115 may be the UE 115c or the UE 115d operating in the service area of ​​the base station 105f. In order to access the small cell base station 105f, the UE 115 will be included in the accessible UE list of the small cell base station 105f. In addition, the base station 105 may be a base station of some other type. Figure 2 As shown in , the base station 105 may be equipped with antennas 234a through 234t, and the UE 115 may be equipped with antennas 252a through 252r, for facilitating wireless communication.

[0042] At the base station 105, the transmit processor 220 may receive data from a data source 212 and control information from a controller 240. The control information may be for a physical broadcast channel (PBCH), a physical control format indicator channel (PCFICH), a physical hybrid ARQ (automatic repeat request) indicator channel (PHICH), a physical downlink control channel (PDCCH), an enhanced physical downlink control channel (EPDCCH), or an MTC physical downlink control channel (MPDCCH), among others. Data may be for a PDSCH, among others. The transmit processor 220 may process (e.g., encode and symbol map) the data and control information, respectively, to obtain data symbols and control symbols. Furthermore, the transmit processor 220 may generate reference symbols, such as those for a primary synchronization signal (PSS) and a secondary synchronization signal (SSS), as well as a cell-specific reference signal. The transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing on the data symbols, control symbols, or reference symbols (if applicable), and may provide output symbol streams to modulators (MODs) 232a through 232t. For example, spatial processing performed on data symbols, control symbols, or reference symbols may include pre-decoding. Each modulator 232 may process a corresponding output symbol stream (such as for OFDM) to obtain an output sample stream. Each modulator 232 may additionally or alternatively process the output sample stream to obtain a downlink signal. For example, to process the output sample stream, each modulator 232 may convert the output sample stream to analog, amplify, filter, and upconvert the output sample stream to obtain a downlink signal. The downlink signals from modulators 232a to 232t may be transmitted via antennas 234a to 234t, respectively.

[0043] At UE 115, antennas 252a through 252r may receive downlink signals from base station 105 and may provide received signals to demodulators (DEMODs) 254a through 254r, respectively. Each demodulator 254 may condition a corresponding received signal to obtain input samples. For example, to condition the corresponding received signal, each demodulator 254 may filter, amplify, downconvert, and digitize the corresponding received signal to obtain input samples. Each demodulator 254 may further process the input samples (such as for OFDM) to obtain received symbols. MIMO detector 256 may obtain received symbols from demodulators 254a through 254r, perform MIMO detection on the received symbols as needed, and provide detected symbols. Receive processor 258 may process the detected symbols, provide decoded data for UE 115 to data sink 260, and provide decoded control information to controller 280. For example, to process the detected symbols, receive processor 258 may demodulate, deinterleave, and decode the detected symbols.

[0044] On the uplink, at the UE 115, a transmit processor 264 may receive and process data from a data source 262 (e.g., for a physical uplink shared channel (PUSCH)) and control information from a controller 280 (e.g., for a physical uplink control channel (PUCCH)). Additionally, the transmit processor 264 may generate reference symbols for reference signals. The symbols from the transmit processor 264 may be pre-decoded by a TX MIMO processor 266, if applicable, further processed by modulators 254a through 254r (e.g., for SC-FDM), and transmitted to the base station 105. At the base station 105, the uplink signal from the UE 115 may be received by the antenna 234, processed by the demodulator 232, detected by the MIMO detector 236, if applicable, and further processed by the receive processor 238 to obtain decoded data and control information transmitted by the UE 115. The receive processor 238 may provide the decoded data to the data sink 239 and the decoded control information to the controller 240.

[0045] The controllers 240 and 280 may direct the operation at the base station 105 and the UE 115, respectively. The controller 240 or other processors and modules at the base station 105, or the controller 280 or other processors and modules at the UE 115, may perform or direct the execution of various processes for the techniques described herein, such as performing or directing Figure 6 and Figure 7 Memories 242 and 282 may store data and program codes for base station 105 and UE 115, respectively. Scheduler 244 may schedule UEs for data transmission on the downlink or uplink.

[0046] In some cases, the UE 115 and the base station 105 may operate in a shared radio frequency spectrum band, which may include licensed spectrum or unlicensed spectrum (e.g., contention-based). In the unlicensed frequency portion of the shared radio frequency spectrum band, the UE 115 or the base station 105 may traditionally perform medium sensing procedures to contend for access to the spectrum. For example, the UE 115 or the base station 105 may perform a listen-before-talk or listen-before-transmit (LBT) procedure (such as a clear channel assessment (CCA)) before communicating to determine whether the shared channel is available. The CCA may include an energy detection procedure to determine whether there are any other active transmissions. For example, the device may infer that a change in the received signal strength indicator (RSSI) of a power meter indicates that the channel is occupied. Specifically, a signal power concentrated in a certain bandwidth and exceeding a predetermined noise floor may indicate another wireless transmitter. In some embodiments, the CCA may include detection of a specific sequence indicating channel usage. For example, another device may send a specific preamble before sending a data sequence. In some cases, the LBT procedure may include the wireless node acting as a proxy for collisions to adjust its own backoff window based on the amount of energy detected on the channel or acknowledgment or negative acknowledgment (ACK or NACK) feedback for its own transmitted packets.

[0047] Figure 3 1 is a block diagram of an example wireless communication system 300 that supports RRC state selection for multicast service reception according to one or more aspects. In some examples, the wireless communication system 300 can implement aspects of the wireless network 100. The wireless communication system 300 includes a UE 115 and a base station 105. Although one UE 115 and one base station 105 are shown, in some other implementations, the wireless communication system 300 can generally include multiple UEs 115 and can include more than one base station 105.

[0048] The UE 115 may include various components (such as structures, hardware components) for performing one or more functions described herein. For example, the UE 115 may include one or more processors 302 (hereinafter collectively referred to as "processor 302"), one or more memory devices 304 (hereinafter collectively referred to as "memory 304"), one or more transmitters 316 (hereinafter collectively referred to as "transmitter 316"), and one or more receivers 318 (hereinafter collectively referred to as "receiver 318"). The processor 302 may be configured to execute instructions stored in the memory 304 to perform one or more operations described herein. In some implementations, the processor 302 includes or corresponds to one or more of the receive processor 258, the transmit processor 264, and the controller 280, and the memory 304 includes or corresponds to the memory 282.

[0049] The transmitter 316 is configured to transmit reference signals, control information, and data to one or more other devices, and the receiver 318 is configured to receive reference signals, synchronization signals, control information, and data from one or more other devices. For example, the transmitter 316 may transmit signaling, control information, and data to the base station 105, and the receiver 318 may receive signaling, control information, and data from the base station 105. In some implementations, the transmitter 316 and the receiver 318 may be integrated into one or more transceivers. Additionally or alternatively, the transmitter 316 or the receiver 318 may include a reference signal. Figure 2 One or more components of the described UE 115 may correspond to those of reference Figure 2 One or more components of the UE 115 are described.

[0050] The base station 105 may include various components (such as structures, hardware components) for performing one or more functions described herein. For example, the base station 105 may include one or more processors 352 (hereinafter collectively referred to as "processor 352"), one or more memory devices 354 (hereinafter collectively referred to as "memory 354"), one or more transmitters 356 (hereinafter collectively referred to as "transmitter 356"), and one or more receivers 358 (hereinafter collectively referred to as "receiver 358"). The processor 352 may be configured to execute instructions stored in the memory 354 to perform one or more operations described herein. In some specific implementations, the processor 352 includes or corresponds to one or more of the receive processor 238, the transmit processor 220, and the controller 240, and the memory 354 includes or corresponds to the memory 242.

[0051] The transmitter 356 is configured to transmit reference signals, synchronization signals, control information, and data to one or more other devices, and the receiver 358 is configured to receive reference signals, control information, and data from one or more other devices. For example, the transmitter 356 may transmit signaling, control information, and data to the UE 115, and the receiver 358 may receive signaling, control information, and data from the UE 115. In some implementations, the transmitter 356 and the receiver 358 may be integrated into one or more transceivers. Additionally or alternatively, the transmitter 356 or the receiver 358 may include a reference signal. Figure 2 One or more components of the base station 105 described may correspond to those of reference Figure 2 One or more components of a base station 105 are described.

[0052] In some implementations, the wireless communication system 300 implements a 5G New Radio (NR) network. For example, the wireless communication system 300 can include a plurality of 5G-capable UEs 115 and a plurality of 5G-capable base stations 105, such as UEs and base stations configured to operate according to a 5G NR network protocol, such as defined by 3GPP.

[0053] During operation of the wireless communication system 300, the UE 115 can operate in multiple states. The multiple states can include a radio resource control (RRC) connected state 306 and an RRC inactive state 308. For illustration, in some implementations, when operating in the RRC connected state 306, the UE 115 can be associated with an active RRC connection to the base station 105, and when operating in the RRC inactive state 308, the UE 115 can be associated with an inactive RRC connection to the base station 105.

[0054] Base station 105 can provide multicast service 360 ​​to one or more UEs, such as UE 115. In some examples, base station 105 can provide multicast service 360 ​​according to a multicast and broadcast service (MBS) protocol, such as a 5G NR MBS protocol. Providing multicast service 360 ​​can include sending multicast data to multiple different UEs 115. In some examples, multicast service 360 ​​can act as a multicast station.

[0055] To receive messaging associated with multicast service 360, such as multicast data, UE 115 may subscribe to (or "join") multicast service 360. Joining multicast service 360 ​​may also be referred to as subscribing to multicast service 360. In some examples, subscribing to multicast service 360 ​​may include sending a multicast service subscription message 330 to base station 105 while operating in RRC connected state 306. For example, base station 105 may indicate (or may "advertise") the availability of multicast service 360, such as by sending signaling indicating the availability of multicast service 360. One or more UEs, such as UE 115, may subscribe to multicast service 360 ​​based on the signaling. For example, UE 115 may send a multicast service subscription message 330 to base station 105 based on the signaling to subscribe to multicast service 360.

[0056] After subscribing to multicast service 360, UE 115 may receive multicast data associated with multicast service 360. For example, base station 105 may perform multicast transmission 344, and a group of one or more UEs including UE 115 may receive multicast transmission 344. In some examples, UE 115 may receive multicast transmission 344 while operating in RRC connected state 306. In some other examples, UE 115 may receive multicast transmission 344 while operating in RRC inactive state 308.

[0057] In some cases, the base station 105 may send a message 334 indicating a change from the RRC connected state 306 to the RRC inactive state 308. For example, if the base station 105 determines that no data is available or scheduled to be sent to the UE 115, the base station 105 may send the message 334 to the UE 115 to initiate the change from the RRC connected state 306 to the RRC inactive state 308, which may reduce power consumption associated with the UE 115.

[0058] Based on message 334, UE 115 may transition from RRC connected state 306 to RRC inactive state 308. To illustrate, in some implementations, transitioning from RRC connected state 306 to RRC inactive state 308 may include placing transmitter 316 in an inactive or low-power mode of operation, such as by powering off one or more components of transmitter 316 or by placing the one or more components in a standby mode of operation.

[0059] In some cases, operation of UE 115 in RRC inactive state 308 may reduce the multicast reliability of UE 115, such as due to a lack of uplink feedback for the multicast radio bearer from UE 115 and a lack of subsequent retransmissions from base station 105. For illustration, in RRC connected state 306, UE 115 may access an uplink control channel for sending feedback to base station 105 and initiating retransmissions of data. In RRC inactive state 308, UE 115 may be unable to access the uplink control channel and may be unable to send feedback to the base station to initiate retransmissions of data (e.g., due to the inactive mode of transmitter 316). Therefore, if UE 115 fails to correctly receive or decode multicast transmission 344 while operating in RRC inactive state 308, UE 115 may be unable to initiate retransmissions of multicast transmission 344, thereby reducing the communication reliability associated with multicast service 360 ​​of UE 115. As an illustrative example, such communication reliability may not be desirable or feasible in some implementations, such as in some ultra-reliable, low-latency communication (URLLC) implementations.

[0060] Some wireless communication protocols can improve communication reliability by ensuring that the UE is in a connected state to receive multicast transmissions. Such techniques may be associated with increased power consumption by the UE, which may be undesirable or impractical in some applications (such as, as an illustrative example, wireless sensor applications).

[0061] To illustrate, in some examples, UE 115 may receive a paging message 338 from base station 105 while operating in RRC inactive state 308. Paging message 338 may indicate that UE 115 will transition to RRC connected state 306 to receive an upcoming transmission, such as multicast transmission 344. Depending on the example, paging message 338 may be a group paging message (which may be addressed to a group of UEs subscribed to multicast service 360) or a unicast paging message addressed individually to UE 115. Furthermore, paging message 338 may be a core network (CN) paging message or a radio access network (RAN) paging message. Paging message 338 may include an indication of a temporary mobile group identity (TMGI) associated with multicast service 360.

[0062] In some aspects of the present disclosure, the UE 115 and the base station 105 may perform operations to enable selection between the RRC connected state 306 and the RRC inactive state 308 to receive one or more multicast transmissions, such as the multicast transmission 344. For illustration, in some examples, the paging message 338 may include an indication 342 (such as a trigger indication) associated with selecting one of the RRC inactive state 308 or the RRC connected state 306 to receive the multicast transmission 344. In some implementations, the indication 342 may include or may be an information element (IE) or UE assistance information included in the paging message 338. One or more aspects described herein may enable one or more UEs to operate in the RRC inactive state 308 to receive the multicast transmission 344 (which may reduce power consumption of these UEs) while also enabling one or more other UEs to operate in the RRC connected state 306 to receive the multicast transmission 344 (which may improve communication reliability associated with these UEs).

[0063] In some examples, indication 342 may specify that UE 115 is to remain in RRC inactive state 308 to receive multicast transmission 344 based on priority 310 associated with UE 115. For illustration, indication 342 may specify that UEs associated with a first priority level are to remain in RRC inactive state 308 to receive multicast transmission 344, and may also specify that UEs associated with a second priority level, which is higher than the first priority level, are to transition to RRC connected state 306 to receive multicast transmission 344. Thus, UE 115 may remain in RRC inactive state 308 based on priority level 310 corresponding to the first priority level, or may transition to RRC connected state 306 based on priority level 310 corresponding to the second priority level. In a non-limiting example, the first priority level may correspond to a low priority level that may be associated with some wireless sensor applications, and the second priority level may correspond to a high priority level that may be associated with some URLLC applications.

[0064] UE 115 may use one or more techniques to determine priority 310. In some examples, UE 115 may determine priority 310 during joining multicast service 360, such as during a non-access stratum (NAS)-based session join procedure or during a NAS-based session modification procedure associated with multicast service 360. In an illustrative example, UE 115 may use a non-access stratum (NAS) layer associated with UE 115 to determine priority 310, such as during joining multicast service 360. After receiving paging message 338, UE 115 may provide an indication 342 from an RRC layer associated with UE 115 to the NAS layer. Based on priority 310 and further based on indication 342, UE 115 may use the NAS layer to determine whether to remain in RRC inactive state 308 to receive multicast transmission 344 or to transition to RRC connected state 306 to receive multicast transmission 344.

[0065] In some other examples, indication 342 may directly indicate whether UE 115 is to remain in RRC inactive state 308 or whether UE 115 is to transition to RRC connected state 306 to receive multicast transmission 344. In such examples, indication 342 may be used without or independently of priority 310. In some such examples, the presence of indication 342 in paging message 338 may indicate that UE 115 is to activate multicast radio bearer (MRB) 320 and remain in RRC inactive state 308 to receive multicast transmission 344 via MRB 320. The absence of indication 342 in paging message 338 may indicate that UE 115 is to transition to RRC connected state 306 to receive multicast transmission 344.

[0066] In some other examples, base station 105 may send an indicator of a priority associated with multicast service 360, such as multicast service priority 362, to UE 115 (prior to sending paging message 338). Multicast service priority 362 may indicate that multicast service 360 ​​is associated with one of a plurality of priorities, such as a first priority or a second priority that is higher than the first priority. Depending on the example, as illustrative examples, the indicator may correspond to or may be one of an RRC message, a system information block (SIB), or a NAS message. Indication 342 may specify that UE 115 is to transition to RRC connected state 306 based on multicast service priority 362 to receive multicast transmission 344. To further illustrate, after receiving the indicator of multicast service priority 362, the presence of indication 342 in paging message 338 may indicate that UE 115 will remain in RRC inactive state 308 to receive multicast transmission 344, and the absence of indication 342 in paging message 338 may indicate that UE 115 will transition to RRC connected state 306 to receive multicast transmission 344.

[0067] In some other examples, paging message 338 may be a unicast paging message that may be individually addressed to UE 115 (such as, rather than a group paging message that may be addressed to a group of UEs subscribed to multicast service 360). In some such examples, indication 342 may include a UE-specific RAN paging identifier (ID) associated with UE 115, and paging message 338 may be an inactive radio network temporary identifier (I-RNTI)-based unicast message transmitted to the high-priority UE to trigger resumption of RRC connected state 306. To further illustrate, the presence of indication 342 in paging message 338 may indicate that UE 115 is to transition to RRC connected state 306 to receive multicast transmission 344. In some such examples, UE 115 may be a high-priority UE. In some other examples, indication 342 may be associated with TMGI 364, and the presence of indication 342 in paging message 338 may indicate that a UE associated with TMGI 364, such as UE 115, is to remain in RRC inactive state 308 to receive multicast transmission 344. In some such examples, the presence of indication 342 in paging message 338 may indicate that UE 115 is to remain in RRC inactive state 308 to receive multicast transmission 344, and the absence of indication 342 in paging message 338 may indicate that UE 115 is to transition to RRC connected state 306 to receive multicast transmission 344. In some such examples, UE 115 may be a low priority UE.

[0068] In some other examples, UEs subscribed to the multicast service 360 ​​may be assigned to groups, and the base station 105 may select between the RRC connected state 306 and the RRC inactive state 308 for each of these groups. For illustration, the base station 105 may send a group identifier 366 associated with the UE 115, such as a high priority group or a low priority group, to the UE 115 (such as via NAS signaling or via RRC signaling). The paging message 338 may include group information associated with the indication 342. For example, the group information may specify one or more groups to which the indication 342 applies. In some such examples, the UE 115 may transition to the RRC connected state 306 based on the group information matching the group identifier 366 associated with the UE 115, or the UE 115 may remain in the RRC inactive state 308 based on group information different from the group identifier 366. In some implementations, the paging message 338 may be a group RAN paging message and may indicate a core network ID (such as a 5G short temporary mobile subscriber identity (S-TMSI)) and a TMGI or I-RNTI, which may cause one or more UEs associated with the core network ID and the TMGI or I-RNTI to transition to an RRC idle state and respond to the paging message 338, such as by sending a NAS service request or by initiating an RRC connection establishment procedure.

[0069] In some other examples, multicast service 360 ​​may be associated with multiple TMGIs, such as a first TMGI and a second TMGI. The first TMGI may be associated with a first group of UEs, such as UEs associated with a first priority. The second TMGI may be associated with a second group of UEs, such as UEs associated with a second priority that is higher than the first priority. Paging message 338 may include one or more of the first TMGI or the second TMGI. The presence of the first TMGI in paging message 338 may indicate that the UEs of the first group will remain in RRC inactive state 308 to receive multicast transmission 344, and the presence of the second TMGI in paging message 338 may indicate that the UEs of the second group will operate in RRC connected state 306 to receive multicast transmission 344. To further illustrate, based on UE 115 being associated with the first priority, UE 115 may remain in RRC inactive state 308 to receive multicast transmission 344. Based on UE 115 being associated with the second priority, UE 115 may transition to RRC connected state 306 to receive multicast transmission 344.

[0070] Alternatively, or in addition to supporting RRC state selection for receiving multicast transmissions 344, some aspects of the present disclosure support deactivating multicast service 360 ​​while operating in RRC inactive state 308. For illustration, when UE 115 is operating in RRC inactive state 308, base station 105 may send a deactivation message 348 to UE 115. Deactivation message 348 may indicate suspension of radio bearer resources associated with multicast service 360. Suspension of radio bearer resources may be based on inactivity associated with multicast service 360, such as a threshold time period during which no multicast transmissions of multicast service 360 ​​are scheduled for execution by base station 105. The radio bearer resources may be associated with MRB 320. In some examples, deactivation message 348 may indicate that the radio bearer resources are being released by base station 105. In some examples, after base station 105 releases the radio bearer resources, UE 115 may suspend use of the radio bearer resources without discarding the radio bearer resources. For example, the UE 115 may reserve radio bearer resources while also ceasing to use the radio bearer resources for monitoring or receiving data.

[0071] In some examples, the deactivation message 348 may be received in a medium access control (MAC) control element (MAC-CE) scheduled by a downlink scheduling message 346 indicating a group radio network temporary identifier (G-RNTI) associated with the multicast service 360. For illustration, the UE 115 may receive the downlink scheduling message 346 from the base station 105, such as via a PDCCH or PDSCH transmission. The downlink scheduling message 346 may indicate the multicast service 360. For example, bits of the downlink scheduling message 346 may be scrambled with the G-RNTI associated with the multicast service 360.

[0072] In some other examples, downlink scheduling message 346 can include downlink control information (DCI) scheduling bits scrambled with a G-RNTI associated with multicast service 360. The DCI scheduling bits can be PDCCH scheduling bits. By scrambling the DCI scheduling bits with the G-RNTI associated with multicast service 360, downlink scheduling message 346 can indicate that deactivation message 348 is associated with multicast service 360.

[0073] In some other examples, UE 115 may receive an MRB configuration via a multicast control channel (MCCH) to enable UE 115 to receive multicast service 360 ​​when operating in RRC inactive state 308, and deactivation message 348 may be indicated by one or more bits of an MCCH change notification associated with the MCCH. The MRB configuration may be associated with MRB 320, and UE 115 may use the MCCH to receive transmissions of multicast service 360, such as multicast transmission 344. In one example, a bit (such as a first bit) of the one or more bits may indicate that the MCCH change notification is due to suspension of radio bearer resources. Alternatively or in addition, a bit (such as a second bit different from the first bit) of the one or more bits may indicate that the MCCH change notification is due to session activation associated with multicast service 360 ​​or due to an update of a neighbor cell list associated with multicast service 360. The one or more bits may be indicated by an MCCH change notification bit, such as in some implementations using multiple MCCHs. In some other examples, other bits may be used, such as in some implementations where the same MCCH is used for both broadcast and multicast transmissions.

[0074] In some other examples, deactivation message 348 may be a TMGI-based group paging message that includes a multicast session stop indicator. For example, deactivation message 348 may be addressed to a group of UEs subscribed to multicast service 360. Deactivation message 348 may indicate TMGI 364, and the multicast session stop indicator may indicate that multicast service 360 ​​is deactivated. The stop indicator may be associated with TMGI 364.

[0075] In some other examples, deactivation message 348 may be received in a downlink scheduling message, such as downlink scheduling message 346, that indicates a multicast paging radio network temporary identifier (P-RNTI) associated with multicast service 360. For example, downlink scheduling message 346 may include a DCI short indicator field, and one or more bits of the DCI short indicator field may indicate (or represent) deactivation message 348.

[0076] For illustration, the multicast P-RNTI may be used to scramble cyclic redundancy check (CRC) bits of the downlink scheduling message 346. The P-RNTI may be generated based on the G-RNTI associated with the multicast service 360. In some examples, the downlink scheduling message 346 may be a PDCCH DCI of type 1_0. In some examples, the DCI short indicator field of the downlink scheduling message 346 may have one or more characteristics described with reference to the example of Table 1.

[0077] <![CDATA[ Bit Field :]]> <![CDATA[ DCI Short Indicator Field :]]> 00 (Reserved) 01 The DCI only contains scheduling information for paging. 10 Only short messages exist in DCI 11 DCI contains both scheduling information and short messages for paging.

[0078] Table 1

[0079] The example of Table 1 illustrates that the bits of the DCI short indicator field can indicate whether a short message is present in the downlink scheduling message 346. If a short message is present in the downlink scheduling message 346 (such as when the bit field has a value of "10" or "11"), the short message can be interpreted according to Table 2.

[0080]

[0081] Table 2

[0082] As shown in the example of Table 2, if there is a short message in the downlink scheduling message 346, the short message may include eight bits (or another number of bits). The bits of the short message may include a multicast service deactivation warning bit. In the example of Table 2, the multicast service deactivation warning bit may correspond to the fourth bit of the short message. In other specific implementations, the multicast service deactivation warning bit may correspond to another bit of the short message. In the example of Table 2, if the fourth bit is set to "1", the multicast service deactivation warning bit may indicate that the reception of multicast services is to be stopped in the RRC inactive state 308, such as by transitioning to the RRC connected state 306 to receive the multicast transmission 344.

[0083] As reference Figure 3 As described, the present disclosure provides techniques for reducing power consumption in a wireless communication system 300 while improving communication reliability in the wireless communication system 300. For example, some UEs may remain in the RRC inactive state 308 to receive the multicast transmission 344 (which may reduce power consumption), while other UEs may transition to the RRC connected state 306 to receive the multicast transmission 344 (which may improve communication reliability associated with reception of the multicast transmission 344). Thus, performance associated with the multicast service 360 ​​may be improved by reducing power consumption of one or more UEs while improving communication reliability of one or more other UEs.

[0084] Figure 4 is a flow chart illustrating an example process 400 for supporting RRC state selection for multicast service reception in accordance with one or more aspects. The operations of process 400 may be performed by a UE (such as the one described above with reference to FIG. Figures 1 to 3 UE 115 as described or as referenced Figure 6 For example, the example operations (also referred to as "blocks") of process 400 may enable UE 115 to select RRC connected state 306 or RRC inactive state 308 to receive Figure 3 Multicast sent 344.

[0085] In block 402, UE 115 subscribes to a multicast service while operating in an RRC connected state. For example, when operating in RRC connected state 306, UE 115 may subscribe to multicast service 360.

[0086] In block 404, the UE 115 transitions from the RRC connected state to the RRC inactive state. For example, the UE 115 may transition from the RRC connected state 306 to the RRC inactive state 308.

[0087] In block 406, while operating in the RRC inactive state, the UE 115 receives a paging message associated with the multicast service. The paging message includes an indication of whether the UE will remain in the RRC inactive state or will transition from the RRC inactive state to the RRC connected state. For example, the UE 115 may receive the paging message 338 while operating in the RRC inactive state 308, and the paging message 338 may include an indication 342 of whether the UE 115 will remain in the RRC inactive state 308 or will transition from the RRC inactive state 308 to the RRC connected state 306.

[0088] In block 408, UE 115 receives a multicast transmission associated with the multicast service while operating in one of the RRC inactive state or the RRC connected state. The one of the RRC inactive state or the RRC connected state is based on the indication. For example, while operating in one of the RRC inactive state 308 or the RRC connected state 306, UE 115 may receive the multicast transmission 344. The one of the RRC inactive state 308 or the RRC connected state 306 may be based on the indication 342.

[0089] Figure 5 is a flow chart illustrating an example process 500 for supporting RRC state selection for multicast service reception according to one or more aspects. The operations of process 500 may be performed by a base station, such as described above with reference to Figures 1 to 3 Base station 105 as described or as referenced Figure 7 For example, the example operations of process 500 may enable base station 105 to select RRC connected state 306 or RRC inactive state 308 to receive Figure 3 Multicast sent 344.

[0090] In block 502, the base station 105 receives a subscription message associated with a multicast service when the UE is operating in the RRC connected state. For example, the base station 105 may receive the multicast service subscription message 330 from the UE 115 when the UE is operating in the RRC connected state 306.

[0091] In block 504, the base station 105 transmits a paging message associated with the multicast service while the UE is operating in the RRC inactive state. The paging message includes an indication of whether the UE will remain in the RRC inactive state or will transition from the RRC inactive state to the RRC connected state. For example, the base station 105 may transmit the paging message 338, and the paging message 338 may include an indication 342 of whether the UE 115 will remain in the RRC inactive state 308 or will transition from the RRC inactive state 308 to the RRC connected state 306.

[0092] In block 506, the base station 105 transmits a multicast transmission associated with the multicast service when the UE is operating in one of the RRC inactive state or the RRC connected state. The one of the RRC inactive state or the RRC connected state is based on the indication. For example, when the UE 115 is operating in one of the RRC inactive state 308 or the RRC connected state 306, the base station 105 may perform the multicast transmission 344. The one of the RRC inactive state 308 or the RRC connected state 306 may be based on the indication 342.

[0093] Figure 6 is a block diagram of an example UE 600 supporting RRC state selection for multicast service reception according to one or more aspects. The UE 600 may be configured to perform operations including referring to Figure 4 In some implementations, the UE 600 includes a block of the process 400. Figure 2 or Figure 3 1 and 115. For example, the UE 600 includes a controller 280 that operates to execute logic or computer instructions stored in a memory 282 and controls components of the UE 600 for providing the features and functionality of the UE 600. The UE 600 transmits and receives signals via radios 601a-r and antennas 252a-r under the control of the controller 280. The radios 601a-r include, for example, Figure 2 Various components and hardware are shown for UE 115 , including modulators and demodulators 254 a - r , a MIMO detector 256 , a receive processor 258 , a transmit processor 264 , and a TX MIMO processor 266 .

[0094] As shown, the memory 282 may include signal transmission logic 602, signal reception logic 603, and RRC state selection logic 604. The controller 280 may execute the signal transmission logic 602 to transmit one or more signals, such as the multicast service subscription message 330. The controller 280 may execute the signal reception logic 603 to receive one or more signals, such as the paging message 338 and the multicast transmission 344. The controller 280 may execute the RRC state selection logic 604 to select between the RRC connected state 306 and the RRC inactive state 308, such as based on the indication 342. The UE 600 may receive a plurality of signals from one or more network entities, such as the multicast service subscription message 330. Figures 1 to 3 Base station 105 or as Figure 7 The base station shown in FIG. 4 receives a signal or sends a signal to the one or more network entities.

[0095] In some implementations, the UE 600 may be configured to perform Figure 4 4. For example, the UE 600 may execute signaling logic 602, signal reception logic 603, and RRC state selection logic 604 stored in the memory 282 under the control of the controller 280. The execution environment of the signaling logic 602 provides functionality to perform at least the operations in block 402. The execution environment of the signal reception logic 603 provides functionality to perform at least the operations in blocks 406 and 408. The execution environment of the RRC state selection logic 604 provides functionality to perform at least the operations in block 404 and select an RRC state based on the indication 342.

[0096] Figure 7 is a block diagram of an example base station 700 supporting RRC state selection for multicast service reception according to one or more aspects. The base station 700 may be configured to perform operations including referring to Figure 5 In some implementations, the base station 700 includes a block of the process 500 described in FIG. Figures 1 to 3 The structure, hardware, and components shown and described for base station 105 are shown in FIG. For example, base station 700 may include a controller 240 that operates to execute logic or computer instructions stored in memory 242 and to control the various components of base station 700 that provide the features and functionality of base station 700. Base station 700 transmits and receives signals via radios 701a-t and antennas 234a-t under the control of controller 240. Figure 2 As shown, radios 701 a - t include various components and hardware for base station 105 , including modulators and demodulators 232 a - t , transmit processor 220 , TX MIMO processor 230 , MIMO detector 236 , and receive processor 238 .

[0097] As shown, the memory 242 may include signal receiving logic 702, signal sending logic 703, and indication setting logic 704. The controller 240 may execute the signal receiving logic 702 to receive one or more signals, such as the multicast service subscription message 330. The controller 240 may execute the signal sending logic 703 to send one or more signals, such as the paging message 338 and the multicast transmission 344. The controller 240 may execute the indication setting logic 704 to set an indication 342, such as indicating one of the RRC connected state 306 or the RRC inactive state 308. The base station 700 may receive a plurality of UEs, such as the UEs, from the base station 700. Figures 1 to 3 UE 115 or Figure 6 UE 600) receives a signal or sends a signal to the one or more UEs.

[0098] In some implementations, the base station 700 may be configured to perform Figure 5 5. For purposes of illustration, base station 700 may execute signal reception logic 702, signal transmission logic 703, and indication setting logic 704 stored in memory 242 under the control of controller 240. The execution environment of signal reception logic 702 provides functionality for performing at least the operations in block 502. The execution environment of signal transmission logic 703 provides functionality for performing at least the operations in blocks 504 and 506. The execution environment of indication setting logic 704 provides functionality for setting an indication 342, such as indicating one of the RRC connected state 306 or the RRC inactive state 308.

[0099] In a first aspect, a method for wireless communication performed by a UE includes, while operating in a Radio Resource Control (RRC) Connected state, subscribing to a multicast service and transitioning from the RRC Connected state to an RRC Inactive state. The method also includes, while operating in the RRC Inactive state, receiving a paging message associated with the multicast service. The paging message includes an indication of whether the UE will remain in the RRC Inactive state or transition from the RRC Inactive state to the RRC Connected state. The method also includes, while operating in one of the RRC Inactive state or the RRC Connected state, receiving a multicast transmission associated with the multicast service. The one of the RRC Inactive state or the RRC Connected state is based on the indication.

[0100] In a second aspect, in combination with the first aspect, the indication specifies that the UE is to remain in the RRC inactive state to receive the multicast transmission based on a priority associated with the UE.

[0101] In a third aspect, in combination with one or more of the first or second aspects, the presence of the indication in the paging message indicates that the UE is to activate MRB and remain in the RRC inactive state to receive the multicast transmission.

[0102] In a fourth aspect, in combination with one or more of the first to third aspects, the method includes receiving an indicator of a priority associated with the multicast service, and the indication specifies that the UE will transition to the RRC connected state to receive the multicast transmission based on the priority.

[0103] In a fifth aspect, in combination with one or more of the first to fourth aspects, the paging message is a unicast paging message, the indication includes a UE-specific RAN paging ID associated with the UE, and the presence of the indication in the paging message indicates that the UE is to transition to the RRC connected state to receive the multicast transmission.

[0104] In a sixth aspect, in combination with one or more of the first to fifth aspects, the indication is associated with a TMGI, and the presence of the indication in the paging message indicates that the UE associated with the TMGI will remain in the RRC inactive state to receive the multicast transmission.

[0105] In a seventh aspect, in combination with one or more of the first to sixth aspects, the method includes receiving a group identifier associated with the UE, and the paging message includes group information associated with the indication.

[0106] In an eighth aspect, in combination with one or more of the first to seventh aspects, the paging message includes one or more of a first TMGI associated with a first priority or a second TMGI associated with a second priority higher than the first priority.

[0107] In a ninth aspect, a UE includes at least one processor and a memory coupled to the at least one processor and storing processor-readable instructions, the processor-readable instructions being configured, when executed by the at least one processor, to subscribe to a multicast service and transition from the RRC connected state to an RRC inactive state when operating in an RRC connected state. The at least one processor is further configured to receive a paging message associated with the multicast service when operating in the RRC inactive state. The paging message includes an indication of whether the UE will remain in the RRC inactive state or transition from the RRC inactive state to the RRC connected state. The at least one processor is further configured to receive a multicast transmission associated with the multicast service when operating in one of the RRC inactive state or the RRC connected state. The one of the RRC inactive state or the RRC connected state is based on the indication.

[0108] In a tenth aspect, in combination with the ninth aspect, the indication specifies that the UE is to remain in the RRC inactive state to receive the multicast transmission based on a priority associated with the UE.

[0109] In an eleventh aspect, in combination with one or more of the ninth to tenth aspects, the presence of the indication in the paging message indicates that the UE will activate MRB and remain in the RRC inactive state to receive the multicast transmission.

[0110] In the twelfth aspect, in combination with one or more of the ninth to eleventh aspects, the at least one processor is further configured to receive an indicator of a priority associated with the multicast service, and the indication specifies that the UE will transition to the RRC connected state to receive the multicast transmission based on the priority.

[0111] In the thirteenth aspect, in combination with one or more of the ninth to twelfth aspects, the paging message is a unicast paging message, the indication includes a UE-specific RAN paging ID associated with the UE, and the presence of the indication in the paging message indicates that the UE will transition to the RRC connected state to receive the multicast transmission.

[0112] In a fourteenth aspect, in combination with one or more of aspects nine to thirteen, the indication is associated with a TMGI, and the presence of the indication in the paging message indicates that the UE associated with the TMGI is to remain in the RRC inactive state to receive the multicast transmission.

[0113] In a fifteenth aspect, in combination with one or more of the ninth to fourteenth aspects, the at least one processor is further configured to receive a group identifier associated with the UE, and the paging message includes group information associated with the indication.

[0114] In a sixteenth aspect, in combination with one or more of the ninth to fifteenth aspects, the paging message includes one or more of a first TMGI associated with a first priority or a second TMGI associated with a second priority higher than the first priority.

[0115] In a seventeenth aspect, a method for wireless communication performed by a base station includes receiving a subscription message associated with a multicast service when a UE is operating in an RRC connected state. The method also includes sending a paging message associated with the multicast service when the UE is operating in an RRC inactive state. The paging message includes an indication of whether the UE will remain in the RRC inactive state or will transition from the RRC inactive state to the RRC connected state. The method also includes sending a multicast transmission associated with the multicast service when the UE is operating in one of the RRC inactive state or the RRC connected state. The one of the RRC inactive state or the RRC connected state is based on the indication.

[0116] In the eighteenth aspect, in combination with the seventeenth aspect, the indication specifies that the UE is to remain in the RRC inactive state to receive the multicast transmission based on a priority associated with the UE.

[0117] In a nineteenth aspect, in combination with one or more of the seventeenth aspect or the eighteenth aspect, the presence of the indication in the paging message indicates that the UE will activate MRB and remain in the RRC inactive state to receive the multicast transmission.

[0118] In aspect 20, in combination with one or more of aspects 17 to 19, the method includes sending an indicator of a priority associated with the multicast service, and the indication specifies that the UE will transition to the RRC connected state to receive the multicast transmission based on the priority.

[0119] In aspect 21, in combination with one or more of aspects 17 to 20, the paging message is a unicast paging message, the indication includes a UE-specific RAN paging ID associated with the UE, and the presence of the indication in the paging message indicates that the UE will transition to the RRC connected state to receive the multicast transmission.

[0120] In a twenty-second aspect, in combination with one or more of aspects seventeen to twenty-first, the method includes sending a group identifier associated with the UE, and the paging message includes group information associated with the indication.

[0121] In a twenty-third aspect, in combination with one or more of aspects seventeen to twenty-second, the paging message includes one or more of a first TMGI associated with a first priority or a second TMGI associated with a second priority higher than the first priority.

[0122] In a twenty-fourth aspect, a base station includes at least one processor and a memory coupled to the at least one processor and storing processor-readable code, the processor-readable code being configured, when executed by the at least one processor, to receive a subscription message associated with a multicast service when a UE is operating in an RRC connected state. The at least one processor is further configured to send a paging message associated with the multicast service when the UE is operating in an RRC inactive state. The paging message includes an indication of whether the UE will remain in the RRC inactive state or will transition from the RRC inactive state to the RRC connected state. The at least one processor is further configured to send a multicast transmission associated with the multicast service when the UE is operating in one of the RRC inactive state or the RRC connected state. The one of the RRC inactive state or the RRC connected state is based on the indication.

[0123] In a twenty-fifth aspect, in combination with the twenty-fourth aspect, the indication specifies that the UE will remain in the RRC inactive state to receive the multicast transmission based on a priority associated with the UE.

[0124] In a twenty-sixth aspect, in combination with one or more of the twenty-fourth or twenty-fifth aspects, the presence of the indication in the paging message indicates that the UE will activate MRB and remain in the RRC inactive state to receive the multicast transmission.

[0125] In aspect 27, in combination with one or more of aspects 24 to 26, the at least one processor is further configured to send an indicator of a priority associated with the multicast service, and the indication specifies that the UE will transition to the RRC connected state to receive the multicast transmission based on the priority.

[0126] In aspect 28, in combination with one or more of aspects 24 to 27, the indication is associated with a TMGI, and the presence of the indication in the paging message indicates that the UE associated with the TMGI will remain in the RRC inactive state to receive the multicast transmission.

[0127] In aspect 29, in combination with one or more of aspects 24 to 28, the at least one processor is further configured to send a group identifier associated with the UE, and the paging message includes group information associated with the indication.

[0128] In a thirtieth aspect, in combination with one or more of aspects twenty-fourth to twenty-ninth, the paging message includes one or more of a first TMGI associated with a first priority or a second TMGI associated with a second priority higher than the first priority.

[0129] It will be understood by those skilled in the art that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be mentioned throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, light fields or optical particles, or any combination thereof.

[0130] This article is relative to Figures 1 to 7 The one or more components, functional blocks, and modules may include a processor, an electronic device, a hardware device, an electronic component, a logic circuit, a memory, a software code, a firmware code, or the like, or any combination thereof. Software should be broadly interpreted to mean instructions, instruction sets, codes, code segments, program codes, programs, subroutines, software modules, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, and / or functions, or the like, whether referred to as software, firmware, middleware, microcode, hardware description language, or other terms. In addition, the features discussed herein may be implemented via dedicated processor circuitry, via executable instructions, or a combination thereof.

[0131] It will be further understood by those skilled in the art that the various illustrative logic blocks, modules, circuits, and algorithmic steps described in conjunction with the present disclosure may be implemented as electronic hardware, computer software, or a combination thereof. In order to clearly illustrate this interchangeability of hardware and software, various illustrative components, frames, modules, circuits, and steps have been generally described above in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the specific application and the design constraints proposed for the entire system. Those skilled in the art may implement the described functionality in different ways for each specific application, but such specific implementation decisions should not be interpreted as causing departure from the scope of the present disclosure. It will also be readily appreciated that the order or combination of components, methods, or interactions described herein are merely examples, and that the components, methods, or interactions of various aspects of the present disclosure may be combined or performed in a manner other than that illustrated and described herein.

[0132] The various illustrative logical components, logic blocks, modules, circuits, and algorithmic processes described in conjunction with the specific implementations disclosed herein can be implemented as electronic hardware, computer software, or a combination of both. The interchangeability of hardware and software has been generally described in terms of functionality and exemplified in the various illustrative components, blocks, modules, circuits, and processes described above. Whether such functionality is implemented in hardware or software depends on the specific application and the design constraints imposed on the overall system.

[0133] The hardware and data processing apparatus for implementing the various illustrative logic components, logic blocks, modules, and circuits described in conjunction with the various aspects disclosed herein may be implemented or executed using a general-purpose single-chip or multi-chip processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic components, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, or any conventional processor, controller, microcontroller, or state machine. In some implementations, a processor may be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in combination with a DSP core, or any other such configuration. In some implementations, a particular process and method may be performed by circuits specific to a given function.

[0134] In one or more aspects, the functions described may be implemented in hardware, digital electronic circuitry, computer software, firmware, including the structures disclosed in this specification and their structural equivalents, or in any combination thereof. Implementations of the subject matter described in this specification may also be implemented as one or more computer programs, i.e., one or more modules of computer program instructions encoded on computer storage media for execution by, or for controlling the operation of, data processing apparatus.

[0135] If implemented in software, the function may be stored as one or more instructions or codes on a computer-readable medium or sent via a computer-readable medium. The process of the method or algorithm disclosed herein may be implemented in a processor-executable software module that may reside on a computer-readable medium. Computer-readable media include both computer storage media and communication media, and communication media include any medium that can realize transferring a computer program from one place to another. The storage medium can be any available medium that a computer can access. By way of example and not limitation, such computer-readable media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage devices, magnetic disk storage devices or other magnetic storage devices, or any other medium that can be used to store the desired program code in the form of an instruction or data structure and that can be accessed by a computer. In addition, any connection may be appropriately referred to as a computer-readable medium. Disks and optical disks as used herein include compact discs (CDs), laser discs, optical discs, digital versatile discs (DVDs), floppy disks and blue-ray discs, wherein disks typically reproduce data magnetically, while optical discs reproduce data optically with lasers. The above combination should also be included within the scope of computer-readable media. Additionally, the operations of a method or algorithm may reside as a code and instruction set, or any combination of code and instruction sets, on a machine-readable medium or computer-readable medium, which may be incorporated into a computer program product.

[0136] Various modifications to the specific implementations described in this disclosure will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other specific implementations without departing from the spirit or scope of this disclosure. Therefore, the claims are not intended to be limited to the specific implementations shown herein but are to be accorded the widest scope consistent with this disclosure, the principles and novel features disclosed herein.

[0137] Additionally, one of ordinary skill in the art will readily recognize that the terms "upper" and "lower" are sometimes used for ease of describing the drawings and indicate relative positions corresponding to the orientation of the drawings on a correctly oriented page and may not reflect the correct orientation of any device as implemented.

[0138] Certain features described in this specification in the context of a single implementation may also be implemented in combination in that single implementation. Conversely, various features described in the context of a single implementation may also be implemented in multiple implementations individually or in any suitable subcombination. Furthermore, while some features are described above as operating in a particular combination and even initially claimed as such, in some cases one or more features from a claimed combination may be cut out of that combination, and a claimed combination may involve subcombinations or variations of subcombinations.

[0139] Similarly, although operations are depicted in a particular order in the figures, this should not be understood as requiring such operations to be performed in the particular order shown or in a sequential order, or to perform all illustrated operations to achieve the desired result. In addition, the accompanying drawings may schematically depict one or more example processes in the form of flow charts. However, other operations not depicted may be incorporated into the schematically illustrated example processes. For example, one or more additional operations may be performed before, after, simultaneously with, or between any of the illustrated operations. In some cases, multitasking and parallel processing are advantageous. In addition, the separation of the various system components in the specific implementations described above should not be understood as requiring such separation in all specific implementations, but rather it should be understood that the described program components and systems can generally be integrated together in a single software product, or packaged into multiple software products. In addition, some other specific implementations also fall within the scope of the appended claims. In some cases, the actions recited in the claims can be performed in different orders and still achieve the desired result.

[0140] As used herein, including in the claims, the term "or," when used in a list of two or more items, means that any one of the listed items can be used alone, or any combination of two or more of the listed items can be used. For example, if a composition is described as comprising component A, B, or C, the composition can comprise A alone; B alone; C alone; A and B combined; A and C combined; B and C combined; or A, B, and C combined. Furthermore, as used herein (including in the claims), "or," as used in a list of items preceded by "at least one," indicates a separate list, such that, for example, a list of "at least one of A, B, or C" means A or B or C or AB or AC or BC or ABC (i.e., A and B and C), or any combination of any of these. The term "substantially" is defined as largely, but not necessarily entirely, what is specified (and includes what is specified; for example, substantially 90 degrees includes 90 degrees, and substantially parallel includes parallel), as understood by one of ordinary skill in the art. In any disclosed embodiment, the term "substantially" may be used in place of "within [percentage] of" that which is specified, where percentages include 0.1%, 1%, 5%, or 10%.

[0141] The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Therefore, the disclosure is not intended to be limited to the examples and designs described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for wireless communication performed by a user equipment (UE), the method comprising: Subscribing to a multicast service when operating in a Radio Resource Control (RRC) connected state; transitioning from the RRC connected state to the RRC inactive state; while operating in the RRC inactive state, receiving a paging message associated with the multicast service, the paging message including an indication of whether the UE is to remain in the RRC inactive state or is to transition from the RRC inactive state to the RRC connected state; as well as A multicast transmission associated with the multicast service is received while operating in one of the RRC inactive state or the RRC connected state, the one of the RRC inactive state or the RRC connected state being based on the indication.

2. The method of claim 1 , wherein the indication specifies that the UE is to remain in the RRC inactive state to receive the multicast transmission based on a priority associated with the UE.

3. The method of claim 1 , wherein the presence of the indication in the paging message indicates that the UE is to activate a multicast radio bearer (MRB) and remain in the RRC inactive state to receive the multicast transmission.

4. The method of claim 1 , further comprising receiving an indicator of a priority associated with the multicast service, wherein the indication specifies that the UE is to transition to the RRC connected state to receive the multicast transmission based on the priority.

5. The method of claim 1 , wherein the paging message is a unicast paging message, wherein the indication comprises a UE-specific radio access network (RAN) paging identifier (ID) associated with the UE, and wherein the presence of the indication in the paging message indicates that the UE is to transition to the RRC connected state to receive the multicast transmission.

6. The method of claim 1 , wherein the indication is associated with a temporary mobile group identity (TMGI), and wherein the presence of the indication in the paging message indicates that a UE associated with the TMGI is to remain in the RRC inactive state to receive the multicast transmission.

7. The method of claim 1, further comprising receiving a group identifier associated with the UE, and wherein the paging message includes group information associated with the indication.

8. The method of claim 1, wherein the paging message comprises one or more of a first temporary mobile group identity (TMGI) associated with a first priority level or a second TMGI associated with a second priority level higher than the first priority level.

9. A user equipment (UE), the user equipment (UE) comprising: at least one processor; and a memory coupled to the at least one processor and storing processor-readable code, the processor-readable code being configured to: Subscribing to a multicast service when operating in a Radio Resource Control (RRC) connected state; transitioning from the RRC connected state to the RRC inactive state; while operating in the RRC inactive state, receiving a paging message associated with the multicast service, the paging message including an indication of whether the UE is to remain in the RRC inactive state or is to transition from the RRC inactive state to the RRC connected state; as well as A multicast transmission associated with the multicast service is received while operating in one of the RRC inactive state or the RRC connected state, the one of the RRC inactive state or the RRC connected state being based on the indication.

10. The UE of claim 9, wherein the indication specifies that the UE is to remain in the RRC inactive state to receive the multicast transmission based on a priority associated with the UE.

11. The UE of claim 9, wherein the presence of the indication in the paging message indicates that the UE is to activate a multicast radio bearer (MRB) and remain in the RRC inactive state to receive the multicast transmission.

12. The UE of claim 9, wherein the at least one processor is further configured to receive an indicator of a priority associated with the multicast service, and wherein the indication specifies that the UE is to transition to the RRC connected state to receive the multicast transmission based on the priority.

13. The UE of claim 9, wherein the paging message is a unicast paging message, wherein the indication comprises a UE-specific radio access network (RAN) paging identifier (ID) associated with the UE, and wherein the presence of the indication in the paging message indicates that the UE is to transition to the RRC connected state to receive the multicast transmission.

14. The UE of claim 9, wherein the indication is associated with a temporary mobile group identity (TMGI), and wherein the presence of the indication in the paging message indicates that the UE associated with the TMGI is to remain in the RRC inactive state to receive the multicast transmission.

15. The UE of claim 9, wherein the at least one processor is further configured to receive a group identifier associated with the UE, and wherein the paging message includes group information associated with the indication.

16. The UE of claim 9, wherein the paging message comprises one or more of a first temporary mobile group identity (TMGI) associated with a first priority level or a second TMGI associated with a second priority level higher than the first priority level.

17. A method for wireless communication performed by a base station, the method comprising: receiving a subscription message associated with a multicast service while a user equipment (UE) is operating in a radio resource control (RRC) connected state; When the UE is operating in the RRC inactive state, sending a paging message associated with the multicast service, the paging message including an indication of whether the UE is to remain in the RRC inactive state or to transition from the RRC inactive state to the RRC connected state; as well as and transmitting a multicast transmission associated with the multicast service while the UE is operating in one of the RRC inactive state or the RRC connected state, the one of the RRC inactive state or the RRC connected state being based on the indication.

18. The method of claim 17, wherein the indication specifies that the UE is to remain in the RRC inactive state to receive the multicast transmission based on a priority associated with the UE.

19. The method of claim 17, wherein the presence of the indication in the paging message indicates that the UE is to activate a multicast radio bearer (MRB) and remain in the RRC inactive state to receive the multicast transmission.

20. The method of claim 17, further comprising transmitting an indicator of a priority associated with the multicast service, wherein the indication specifies that the UE is to transition to the RRC connected state to receive the multicast transmission based on the priority.

21. The method of claim 17, wherein the paging message is a unicast paging message, wherein the indication comprises a UE-specific radio access network (RAN) paging identifier (ID) associated with the UE, and wherein the presence of the indication in the paging message indicates that the UE is to transition to the RRC connected state to receive the multicast transmission.

22. The method of claim 17, further comprising transmitting a group identifier associated with the UE, and wherein the paging message includes group information associated with the indication.

23. The method of claim 17, wherein the paging message includes one or more of a first temporary mobile group identity (TMGI) associated with a first priority level or a second TMGI associated with a second priority level higher than the first priority level.

24. A base station, comprising: at least one processor; and a memory coupled to the at least one processor and storing processor-readable code, the processor-readable code being configured to: receiving a subscription message associated with a multicast service while the UE is operating in a radio resource control (RRC) connected state; When the UE is operating in the RRC inactive state, sending a paging message associated with the multicast service, the paging message including an indication of whether the UE is to remain in the RRC inactive state or to transition from the RRC inactive state to the RRC connected state; as well as and transmitting a multicast transmission associated with the multicast service while the UE is operating in one of the RRC inactive state or the RRC connected state, the one of the RRC inactive state or the RRC connected state being based on the indication.

25. The base station of claim 24, wherein the indication specifies that the UE is to remain in the RRC inactive state to receive the multicast transmission based on a priority associated with the UE.

26. The base station of claim 24, wherein the presence of the indication in the paging message indicates that the UE is to activate a multicast radio bearer (MRB) and remain in the RRC inactive state to receive the multicast transmission.

27. The base station of claim 24, wherein the at least one processor is further configured to send an indicator of a priority associated with the multicast service, and wherein the indication specifies that the UE is to transition to the RRC connected state to receive the multicast transmission based on the priority.

28. The base station of claim 24, wherein the indication is associated with a temporary mobile group identity (TMGI), and wherein the presence of the indication in the paging message indicates that a UE associated with the TMGI is to remain in the RRC inactive state to receive the multicast transmission.

29. The base station of claim 24, wherein the at least one processor is further configured to transmit a group identifier associated with the UE, and wherein the paging message includes group information associated with the indication.

30. The base station of claim 24, wherein the paging message comprises one or more of a first temporary mobile group identity (TMGI) associated with a first priority level or a second TMGI associated with a second priority level higher than the first priority level.

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