Patent Publication Number: US-2023164809-A1

Title: Monitoring multicast broadcast control information

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This patent application is a Continuation of U.S. patent application Ser. No. 17/107,171 filed on 30 Nov. 2020 and entitled “MONITORING MULTICAST BROADCAST CONTROL INFORMATION,” which claims priority to U.S. Provisional Patent Application No. 62/954,829 filed on 30 Dec. 2019 and entitled “MONITORING MULTICAST BROADCAST CONTROL INFORMATION,” both of which are assigned to the assignee hereof. 
    
    
     FIELD OF THE DISCLOSURE 
     Aspects of the present disclosure generally relate to wireless communication and specifically, to techniques and apparatuses for monitoring multicast broadcast control information. 
     BACKGROUND 
     Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (for example, bandwidth, or transmit power, among other examples, or a combination thereof). Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, orthogonal frequency-division multiple access (OFDMA) systems, single-carrier frequency-division multiple access (SC-FDMA) systems, time division synchronous code division multiple access (TD-SCDMA) systems, and Long Term Evolution (LTE). LTE/LTE-Advanced is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP). 
     The above multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different user equipments (UEs) to communicate on a municipal, national, regional, and even global level. New Radio (NR), which may also be referred to as 5G, is a set of enhancements to the LTE mobile standard promulgated by the 3GPP. NR is designed to better support mobile broadband Internet access by improving spectral efficiency, lowering costs, improving services, making use of new spectrum, and better integrating with other open standards using orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) (CP-OFDM) on the downlink (DL), using CP-OFDM or SC-FDMA (for example, also known as discrete Fourier transform spread OFDM (DFT-s-OFDM)) on the uplink (UL), as well as supporting beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation. However, as the demand for mobile broadband access continues to increase, there exists a need for further improvements in LTE and NR technologies. Preferably, these improvements are applicable to other multiple access technologies and the telecommunication standards that employ these technologies. 
     When multicast broadcast (MB) control information is updated, a base station may need to signal such change to UEs served by the base station so that UEs subscribed to MB services can obtain the updated MB control information. Some signaling techniques may be more suitable for some MB system designs as compared to other MB system designs. For example, a signaling technique that improves performance or reduces UE power consumption in one MB system design may not achieve the same results in another MB system design. 
     SUMMARY 
     In some aspects, a method of wireless communication, performed by a user equipment (UE), may include receiving a notification of a change to multicast broadcast (MB) control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in an MB control channel (MBCCH) scheduled by a physical downlink control channel (PDCCH) communication addressed to an MB radio network temporary identifier (MB-RNTI); and monitoring one or more resources of the MBCCH to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     In some aspects, a method of wireless communication, performed by a UE, may include receiving a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in a system information block (SIB) scheduled by a PDCCH communication addressed to a system information radio network temporary identifier (SI-RNTI); and monitoring the SIB to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     In some aspects, a method of wireless communication, performed by a UE, may include receiving a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in a unicast radio resource control (RRC) message scheduled by a PDCCH communication addressed to a cell radio network temporary identifier (C-RNTI); and monitoring the unicast RRC message to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     In some aspects, a method of wireless communication, performed by a base station, may include transmitting a notification of a change to MB control information, the MB control information being included in one of: an MB control channel communication scheduled by a PDCCH communication addressed to an MB radio network temporary identifier, a system information block scheduled by a PDCCH communication addressed to a system information radio network temporary identifier, or a unicast radio resource control message scheduled by a PDCCH communication addressed to a cell radio network temporary identifier; and transmitting updated MB control information based at least in part on transmitting the notification of the change to the MB control information. 
     In some aspects, a UE for wireless communication may include memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to receive a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in an MBCCH scheduled by a PDCCH communication addressed to an MB-RNTI; and monitor one or more resources of the MBCCH to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     In some aspects, a UE for wireless communication may include memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to receive a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in a SIB scheduled by a PDCCH communication addressed to an SI-RNTI; and monitor the SIB to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     In some aspects, a UE for wireless communication may include memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to receive a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in a unicast RRC message scheduled by a PDCCH communication addressed to a C-RNTI; and monitor the unicast RRC message to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     In some aspects, a base station for wireless communication may include memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to transmit a notification of a change to MB control information, the MB control information being included in one of: an MB control channel communication scheduled by a PDCCH communication addressed to an MB radio network temporary identifier, a system information block scheduled by a PDCCH communication addressed to a system information radio network temporary identifier, or a unicast radio resource control message scheduled by a PDCCH communication addressed to a cell radio network temporary identifier; and transmit updated MB control information based at least in part on transmitting the notification of the change to the MB control information. 
     In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a UE, may cause the one or more processors to: receive a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in an MBCCH scheduled by a PDCCH communication addressed to an MB-RNTI; and monitor one or more resources of the MBCCH to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a UE, may cause the one or more processors to: receive a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in a SIB scheduled by a PDCCH communication addressed to an SI-RNTI; and monitor the SIB to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a UE, may cause the one or more processors to: receive a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in a unicast RRC message scheduled by a PDCCH communication addressed to a C-RNTI; and monitor the unicast RRC message to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a base station, may cause the one or more processors to: transmit a notification of a change to MB control information, the MB control information being included in one of: an MB control channel communication scheduled by a PDCCH communication addressed to an MB radio network temporary identifier, a system information block scheduled by a PDCCH communication addressed to a system information radio network temporary identifier, or a unicast radio resource control message scheduled by a PDCCH communication addressed to a cell radio network temporary identifier; and transmit updated MB control information based at least in part on transmitting the notification of the change to the MB control information. 
     In some aspects, an apparatus for wireless communication may include means for receiving a notification of a change to MB control information associated with at least one MB service to which the apparatus is subscribed, the MB control information being included in an MBCCH scheduled by a PDCCH communication addressed to an MB-RNTI; and means for monitoring one or more resources of the MBCCH to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     In some aspects, an apparatus for wireless communication may include means for receiving a notification of a change to MB control information associated with at least one MB service to which the apparatus is subscribed, the MB control information being included in a SIB scheduled by a PDCCH communication addressed to an SI-RNTI; and means for monitoring the SIB to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     In some aspects, an apparatus for wireless communication may include means for receiving a notification of a change to MB control information associated with at least one MB service to which the apparatus is subscribed, the MB control information being included in a unicast RRC message scheduled by a PDCCH communication addressed to a C-RNTI; and means for monitoring the unicast RRC message to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     In some aspects, an apparatus for wireless communication may include means for transmitting a notification of a change to MB control information, the MB control information being included in one of: an MB control channel communication scheduled by a PDCCH communication addressed to an MB radio network temporary identifier, a system information block scheduled by a PDCCH communication addressed to a system information radio network temporary identifier, or a unicast radio resource control message scheduled by a PDCCH communication addressed to a cell radio network temporary identifier; and means for transmitting updated MB control information based at least in part on transmitting the notification of the change to the MB control information. 
     Aspects generally include a method, apparatus, system, computer program product, non-transitory computer-readable medium, user equipment, base station, wireless communication device, or processing system as substantially described with reference to and as illustrated by the drawings and specification. 
     The foregoing has outlined rather broadly the features and technical advantages of examples in accordance with the disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter. The conception and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. Characteristics of the concepts disclosed herein, both their organization and method of operation, together with associated advantages will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purposes of illustration and description, and not as a definition of the limits of the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the above-recited features of the present disclosure can be understood in detail, a more particular description, briefly summarized above, may be had by reference to aspects, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only some typical aspects of this disclosure and are therefore not to be considered limiting of its scope, for the description may admit to other equally effective aspects. The same reference numbers in different drawings may identify the same or similar elements. 
         FIG.  1    is a block diagram illustrating an example wireless network in accordance with various aspects of the present disclosure. 
         FIG.  2    is a block diagram illustrating an example base station (BS) in communication with a user equipment (UE) in a wireless network in accordance with various aspects of the present disclosure. 
         FIG.  3    is a diagram illustrating an example channel mapping for multicast broadcast communications in accordance with various aspects of the present disclosure. 
         FIG.  4    is a diagram illustrating an example of a multicast broadcast control information flow in accordance with various aspects of the present disclosure. 
         FIG.  5    is a diagram illustrating another example of a multicast broadcast control information flow in accordance with various aspects of the present disclosure. 
         FIG.  6    is a diagram illustrating another example of a multicast broadcast control information flow in accordance with various aspects of the present disclosure. 
         FIG.  7    is a diagram illustrating an example of a multicast broadcast control information change notification in accordance with various aspects of the present disclosure. 
         FIG.  8    is a diagram illustrating another example of a multicast broadcast control information flow in accordance with various aspects of the present disclosure. 
         FIG.  9    is a diagram illustrating another example of a multicast broadcast control information change notification in accordance with various aspects of the present disclosure. 
         FIG.  10    is a diagram illustrating another example of a multicast broadcast control information flow in accordance with various aspects of the present disclosure. 
         FIGS.  11 - 13    are flowcharts illustrating example processes performed by a UE in accordance with various aspects of the present disclosure. 
         FIG.  14    is a flowchart illustrating an example process performed by a base station in accordance with various aspects of the present disclosure. 
         FIGS.  15 - 18    are block diagrams of example apparatuses for wireless communication in accordance with various aspects of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Various aspects of the disclosure are described more fully hereinafter with reference to the accompanying drawings. This disclosure may, however, be embodied in many different forms and are not to be construed as limited to any specific structure or function presented throughout this disclosure. Rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Based on the teachings herein one skilled in the art may appreciate that the scope of the disclosure is intended to cover any aspect of the disclosure disclosed herein, whether implemented independently of or combined with any other aspect of the disclosure. For example, an apparatus may be implemented or a method may be practiced using any quantity of the aspects set forth herein. In addition, the scope of the disclosure is intended to cover such an apparatus or method which is practiced using other structure, functionality, or structure and functionality in addition to or other than the various aspects of the disclosure set forth herein. Any aspect of the disclosure disclosed herein may be embodied by one or more elements of a claim. 
     Several aspects of telecommunication systems will now be presented with reference to various apparatuses and techniques. These apparatuses and techniques will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, or algorithms, among other examples, or combinations thereof (collectively referred to as “elements”). These elements may be implemented using hardware, software, or combinations thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. 
     Various aspects relate generally to transmission of multicast broadcast (MB) control information. Some aspects more specifically relate to using a multicast broadcast control channel (MBCCH) to carry MB control information. In some aspects, an MBCCH communication may be scheduled by a physical downlink control channel (PDCCH) communication that is addressed to a multicast broadcast radio network temporary identifier (MB-RNTI). Some aspects more specifically relate to using a system information block (SIB) to carry MB control information. In some aspects, the SIB may be scheduled by a PDCCH communication addressed to a system information RNTI (SI-RNTI). Some aspects more specifically relate to using a unicast radio resource control (RRC) message to carry MB control information. In some aspects, the unicast RRC message may be scheduled by a PDCCH communication addressed to a cell RNTI (C-RNTI). 
     Particular aspects of the subject matter described in this disclosure can be implemented to realize one or more of the following potential advantages. In some examples, the described techniques can be used to improve performance in various MB system designs. For example, using an MBCCH communication or a SIB to carry MB control information provides flexibility because the MBCCH communication and the SIB can be received by a UE in an RRC connected mode, an RRC idle mode, and an RRC inactive mode. Using a SIB may reduce system complexity by using legacy signaling mechanisms without creating a new channel (e.g., the MBCCH), while using an MBCCH may reduce power consumption for UEs not subscribed to MB services by introducing UE-specific signaling of MB control information rather than system-wide signaling via a SIB. As another example, using a unicast RRC message to carry MB control information may be less flexible than using the MBCCH communication and the SIB because the unicast RRC message can only be received by UEs in an RRC connected mode, but may reduce power consumption by only signaling UEs that are subscribed to MB services. Furthermore, some techniques and apparatuses described herein reduce power consumption by partitioning MB services into multiple sets of MB services and using separate notifications, to indicate a change in MB control information, for different sets of MB services. In this example, UEs that are not subscribed to a set of MB services need not obtain MB control information upon receiving a notification of a change in MB control information for that set of MB services, thereby reducing power consumption and extending battery life. Furthermore, some techniques and apparatuses described herein conserve system overhead and network resources by using a short message indicator in downlink control information to indicate a change in MB control information. 
       FIG.  1    is a block diagram illustrating an example wireless network in accordance with various aspects of the present disclosure. The wireless network may be a Long Term Evolution (LTE) network or some other wireless network, such as a 5G or NR network. The wireless network may include a quantity of base stations (BSs)  110  (shown as BS  110   a , BS  110   b , BS  110   c , and BS  110   d ) and other network entities. A BS is an entity that communicates with user equipment (UE(s)) and may also be referred to as a Node B, an eNodeB, an eNB, a gNB, a NR BS, a 5G node B (NB), an access point (AP), or a transmit receive point (TRP), among other examples, or combinations thereof (these terms are used interchangeably herein). Each BS may provide communication coverage for a particular geographic area. In 3GPP, the term “cell” can refer to a coverage area of a BS or a BS subsystem serving this coverage area, depending on the context in which the term is used. 
     A BS may provide communication coverage for a macro cell, a pico cell, a femto cell, or another type of cell. A macro cell may cover a relatively large geographic area (for example, several kilometers in radius) and may allow unrestricted access by UEs with service subscription. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscription. A femto cell may cover a relatively small geographic area (for example, a home) and may allow restricted access by UEs having association with the femto cell (for example, UEs in a closed subscriber group (CSG)). ABS for a macro cell may be referred to as a macro BS. A BS for a pico cell may be referred to as a pico BS. ABS for a femto cell may be referred to as a femto BS or a home BS. A BS may support one or multiple (for example, three) cells. 
     The wireless network may be a heterogeneous network that includes BSs of different types, for example, macro BSs, pico BSs, femto BSs, or relay BSs, among other examples, or combinations thereof. These different types of BSs may have different transmit power levels, different coverage areas, and different impacts on interference in the wireless network. For example, macro BSs may have a high transmit power level (for example, 5 to 40 watts) whereas pico BSs, femto BSs, and relay BSs may have lower transmit power levels (for example, 0.1 to 2 watts). In the example shown in  FIG.  1   , a BS  110   a  may be a macro BS for a macro cell  102   a , a BS  110   b  may be a pico BS for a pico cell  102   b , and a BS  110   c  may be a femto BS for a femto cell  102   c . A network controller  130  may couple to the set of BSs  102   a ,  102   b ,  110   a  and  110   b , and may provide coordination and control for these BSs. Network controller  130  may communicate with the BSs via a backhaul. The BSs may also communicate with one another, for example, directly or indirectly via a wireless or wireline backhaul. 
     In some aspects, a cell may not be stationary, rather, the geographic area of the cell may move in accordance with the location of a mobile BS. In some aspects, the BSs may be interconnected to one another or to one or more other BSs or network nodes (not shown) in the wireless network through various types of backhaul interfaces such as a direct physical connection, or a virtual network, among other examples, or combinations thereof using any suitable transport network. 
     The wireless network may also include relay stations. A relay station is an entity that can receive a transmission of data from an upstream station (for example, a BS or a UE) and send a transmission of the data to a downstream station (for example, a UE or a BS). A relay station may also be a UE that can relay transmissions for other UEs. In the example shown in  FIG.  1   , a relay station  110   d  may communicate with macro BS  110   a  and a UE  120   d  in order to facilitate communication between BS  110   a  and UE  120   d . A relay station may also be referred to as a relay BS, a relay base station, or a relay, among other examples, or combinations thereof. 
     UEs  120  (for example,  120   a ,  120   b ,  120   c ) may be dispersed throughout the wireless network, and each UE may be stationary or mobile. A UE may also be referred to as an access terminal, a terminal, a mobile station, a subscriber unit, or a station, among other examples, or combinations thereof. A UE may be a cellular phone (for example, a smart phone), a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device or equipment, biometric sensors/devices, wearable devices (smart watches, smart clothing, smart glasses, smart wrist bands, smart jewelry (for example, smart ring, smart bracelet)), an entertainment device (for example, a music or video device, or a satellite radio), a vehicular component or sensor, smart meters/sensors, industrial manufacturing equipment, a global positioning system device, or any other suitable device that is configured to communicate via a wireless medium. 
     Some UEs may be considered machine-type communication (MTC) or evolved or enhanced machine-type communication (eMTC) UEs. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors or location tags, among other examples, or combinations thereof, that may communicate with a base station, another device (for example, remote device), or some other entity. A wireless node may provide, for example, connectivity for or to a network (for example, a wide area network such as Internet or a cellular network) via a wired or wireless communication link. Some UEs may be considered Internet-of-Things (IoT) devices, or may be implemented as NB-IoT (narrowband internet of things) devices. Some UEs may be considered a Customer Premises Equipment (CPE). UE  120  may be included inside a housing that houses components of UE  120 , such as processor components, or memory components, among other examples, or combinations thereof. 
     In general, any quantity of wireless networks may be deployed in a given geographic area. Each wireless network may support a particular radio access technology (RAT) and may operate on one or more frequencies or frequency channels. A frequency may also be referred to as a carrier among other examples. Each frequency may support a single RAT in a given geographic area in order to avoid interference between wireless networks of different RATs. In some examples, NR or 5G RAT networks may be deployed. 
     In some aspects, two or more UEs  120  (for example, shown as UE  120   a  and UE  120   e ) may communicate directly with one another using one or more sidelink channels (for example, without using a base station  110  as an intermediary). For example, the UEs  120  may communicate using peer-to-peer (P2P) communications, device-to-device (D2D) communications, a vehicle-to-everything (V2X) protocol (for example, which may include a vehicle-to-vehicle (V2V) protocol, or a vehicle-to-infrastructure (V2I) protocol, among other examples, or combinations thereof), or a mesh network, among other examples, or combinations thereof. In such examples, the UE  120  may perform scheduling operations, resource selection operations, or other operations described elsewhere herein as being performed by the base station  110 . 
       FIG.  2    is a block diagram illustrating an example base station (BS) in communication with a user equipment (UE) in a wireless network in accordance with various aspects of the present disclosure. Base station  110  may be equipped with T antennas  234   a  through  234   t , and UE  120  may be equipped with R antennas  252   a  through  252   r , where in general T≥1 and R≥1. 
     At base station  110 , a transmit processor  220  may receive data from a data source  212  for one or more UEs, select one or more modulation and coding schemes (MCSs) for each UE based at least in part on channel quality indicators (CQIs) received from the UE, process (for example, encode) the data for each UE based at least in part on the MCS(s) selected for the UE, and provide data symbols for all UEs. Transmit processor  220  may also process system information (for example, for semi-static resource partitioning information (SRPI) among other examples) and control information (for example, CQI requests, grants, or upper layer signaling, among other examples, or combinations thereof) and provide overhead symbols and control symbols. Transmit processor  220  may also generate reference symbols for reference signals (for example, the cell-specific reference signal (CRS)) and synchronization signals (for example, the primary synchronization signal (PSS) and secondary synchronization signal (SSS)). A transmit (TX) multiple-input multiple-output (MIMO) processor  230  may perform spatial processing (for example, precoding) on the data symbols, the control symbols, the overhead symbols, or the reference symbols, if applicable, and may provide T output symbol streams to T modulators (MODs)  232   a  through  232   t . Each MOD  232  may process a respective output symbol stream (for example, for OFDM among other examples) to obtain an output sample stream. Each MOD  232  may further process (for example, convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. T downlink signals from MODs  232   a  through  232   t  may be transmitted via T antennas  234   a  through  234   t , respectively. In accordance with various aspects described in more detail below, the synchronization signals can be generated with location encoding to convey additional information. 
     At UE  120 , antennas  252   a  through  252   r  may receive the downlink signals from base station  110  or other base stations and may provide received signals to R demodulators (DEMODs)  254   a  through  254   r , respectively. Each DEMOD  254  may condition (for example, filter, amplify, downconvert, and digitize) a received signal to obtain input samples. Each DEMOD  254  may further process the input samples (for example, for OFDM) to obtain received symbols. A MIMO detector  256  may obtain received symbols from all R DEMODs  254   a  through  254   r , perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor  258  may process (for example, decode) the detected symbols, provide decoded data for UE  120  to a data sink  260 , and provide decoded control information and system information to a controller/processor  280 . A channel processor may determine a reference signal received power (RSRP), a received signal strength indicator (RSSI), a reference signal received quality (RSRQ), or a channel quality indicator (CQI), among other examples, or combinations thereof. In some aspects, one or more components of UE  120  may be included in a housing. 
     On the uplink, at UE  120 , a transmit processor  264  may receive and process data from a data source  262  as well as control information (for example, for reports including RSRP, RSSI, RSRQ, or CQI, among other examples, or combinations thereof) from controller/processor  280 . Transmit processor  264  may also generate reference symbols for one or more reference signals. The symbols from transmit processor  264  may be precoded by a TX MIMO processor  266  if applicable, further processed by MODs  254   a  through  254   r  (for example, for discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM), or orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) (CP-OFDM), among other examples, or combinations thereof), and transmitted to base station  110 . At base station  110 , the uplink signals from UE  120  and other UEs may be received by antennas  234 , processed by DEMODs  232 , detected by a MIMO detector  236  if applicable, and further processed by a receive processor  238  to obtain decoded data and control information sent by UE  120 . Receive processor  238  may provide the decoded data to a data sink  239  and the decoded control information to controller/processor  240 . Base station  110  may include communication unit  244  and communicate to network controller  130  via communication unit  244 . Network controller  130  may include communication unit  294 , controller/processor  290 , and memory  292 . 
     Controller/processor  240  of base station  110 , controller/processor  280  of UE  120 , or any other component(s) of  FIG.  2    may perform one or more techniques associated with multicast broadcast control information, as described in more detail elsewhere herein. For example, controller/processor  240  of base station  110 , controller/processor  280  of UE  120 , or any other component(s) of  FIG.  2    may perform or direct operations of, for example, the process  1100  of  FIG.  11   , the process  1200  of  FIG.  12   , the process  1300  of  FIG.  13   , the process  1400  of  FIG.  14   , or other processes as described herein. Memories  242  and  282  may store data and program codes for base station  110  and UE  120 , respectively. A scheduler  246  may schedule UEs for data transmission on the downlink or uplink. 
     In some aspects, UE  120  may include means for receiving a notification of a change to MB control information associated with at least one MB service to which the UE  120  is subscribed, the MB control information being included in an MBCCH scheduled by a PDCCH communication addressed to an MB-RNTI; means for monitoring one or more resources of the MBCCH to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information; or a combination thereof. Additionally or alternatively, UE  120  may include means for receiving a notification of a change to MB control information associated with at least one MB service to which the UE  120  is subscribed, the MB control information being included in a SIB scheduled by a PDCCH communication addressed to an SI-RNTI; means for monitoring the SIB to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information; or a combination thereof. Additionally or alternatively, UE  120  may include means for receiving a notification of a change to MB control information associated with at least one MB service to which the UE  120  is subscribed, the MB control information being included in a unicast RRC message scheduled by a PDCCH communication addressed to a C-RNTI; means for monitoring the unicast RRC message to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information; or a combination thereof. In some aspects, such means may include one or more components of UE  120  described in connection with  FIG.  2   . 
     In some aspects, base station  110  may include means for transmitting a notification of a change to MB control information, the MB control information being included in one of: an MB control channel communication scheduled by a PDCCH communication addressed to an MB radio network temporary identifier, a system information block scheduled by a PDCCH communication addressed to a system information radio network temporary identifier, or a unicast radio resource control message scheduled by a PDCCH communication addressed to a cell radio network temporary identifier; means for transmitting updated MB control information based at least in part on transmitting the notification of the change to the MB control information; or a combination thereof. In some aspects, such means may include one or more components of base station  110  described in connection with  FIG.  2   . 
       FIG.  3    is a diagram illustrating an example channel mapping for multicast broadcast communications in accordance with various aspects of the present disclosure. In some aspects, multicast or broadcast transmissions in NR may be supported using a multicast broadcast traffic channel (MBTCH)  302  and a multicast broadcast control channel (MBCCH)  304 . The MBTCH  302  may carry multicast or broadcast data, while the MBCCH  304  may carry configuration information or control information for multicast or broadcast communications to be transmitted on the MBTCH  302 . A multicast or broadcast communication on the MBTCH  302  may be addressed to a group of UEs using a group radio network temporary identifier (G-RNTI). 
     In some aspects, different MBTCHs  302  may be used to carry multicast broadcast traffic with different quality of service (QoS) requirements. A multicast/broadcast traffic flow with associated QoS requirements or QoS parameters (for example, a group of related packets for the same multicast/broadcast service) may be referred to as an MB-QoS flow. In some aspects, there may be a one-to-one mapping between MB-QoS flows and MBTCHs  302 . A base station or a core network device may configure a multicast broadcast radio bearer (MRB) for an MB-QoS flow. In some aspects, there may be a one-to-one mapping between MB-QoS flows and MRBs. Thus, each MBTCH  302  may correspond to an MRB for carrying an MB-QoS flow. 
     The MBCCH  304  may carry configuration information for configuring the MBTCHs  302 , and may be addressed to all UEs in a cell (for example, a physical cell or a virtual cell) using a single cell RNTI (SC-RNTI). In some aspects, there is a single MBCCH  304  per cell (physical cell or virtual cell), and the MBCCH  304  carries MBTCH configuration information for multiple multicast/broadcast services with different MB-QoS flows. The MBCCH  304  and the MBTCH  302  are logical channels, and may be mapped to a downlink shared channel (DL-SCH) transport channel  306 , which may be mapped to the PDSCH  308 . 
     The MBCCH  304  may carry multicast broadcast (MB) control information (for example, in an NR BroadcastMulticastConfiguration message) for the MBTCH  302 , such as for an MRB of the MBTCH  302 . The MB control information may include information usable by the UE  120  to receive an MB service (for example, via the MBTCH  302 ). For example, MB control information may indicate a list of G-RNTIs and corresponding MB services, a mapping between MB-QoS flows and G-RNTIs, a mapping between temporary mobile group identities (TMGIs) and G-RNTIs, a mapping between logical channel identifiers (LCIDs) and G-RNTIs, a control resource set (CORESET) configuration for the MBTCH  302 , a set of time domain resources allocated for the MBTCH  302 , a set of frequency domain resources allocated for the MBTCH  302 , or one or more discontinuous reception (DRX) parameters associated with the MBTCH  302 , among other examples. 
     In some MB system designs, the MBCCH  304  may be used to carry MB control information. An MBCCH communication (for example, carrying MB control information for MB communications) may be scheduled by a PDCCH communication that is addressed to a multicast broadcast RNTI (MB-RNTI or M-RNTI). The PDCCH communication and corresponding MBCCH communication may be received by UEs  120  in a radio resource control (RRC) connected mode, an RRC idle mode, and an RRC inactive mode. Thus, this system design is flexible and can be used for all UEs  120  regardless of an RRC mode of a UE  120 . 
     However, other MB system designs may be introduced in NR without the necessity of introducing a new logical channel, such as the MBCCH  304 . For example, MB control information may be carried in a system information block (SIB). The SIB may be scheduled by a PDCCH communication addressed to a system information RNTI (SI-RNTI). Similar to the MBCCH design, the PDCCH communication and the SIB may be received by UEs  120  in an RRC connected mode, an RRC idle mode, and an RRC inactive mode. Thus, this system design is flexible and can be used for all UEs  120  regardless of an RRC mode of a UE  120 . However, when the MB control information changes, such a change may be signaled as a system information update. This may impact UEs  120  that are not subscribed to MB services, and may cause those UEs  120  to unnecessarily obtain updated system information, thereby increasing power consumption and reducing battery life. 
     In another MB system design, MB control information may be carried in a unicast RRC message between a base station  110  and a UE  120 . The unicast RRC message may be scheduled by a PDCCH communication addressed to a cell RNTI (C-RNTI). In this example, the MB control information can be received by UEs  120  in an RRC connected mode, but not UEs  120  in an RRC idle mode or an RRC inactive mode. Because UEs  120  in an RRC idle mode or an RRC inactive mode may be capable of receiving MB services, this MB system design may be inefficient. However, this MB system design impacts only UEs  120  that are subscribed to MB services, thereby reducing power consumption of UEs  120  as compared to the SIB design described above. 
     When the MB control information is updated, a base station  110  may need to signal such change to UEs  120  served by the base station  110  so that UEs  120  subscribed to MB services can obtain the updated MB control information. Some signaling techniques may be more suitable for some MB system designs as compared to other MB system designs. For example, a signaling technique that improves performance or reduces UE power consumption in one MB system design may not achieve the same results in another MB system design. Some techniques and apparatuses described herein improve performance of MB control information monitoring, as well as signaling of changes to MB control information, for various MB system designs. For example, some techniques and apparatuses described herein partition MB services into multiple sets of MB services and use a separate notification, for each set of MB services, to indicate a change in MB control information for a corresponding set of MB services. As a result, UEs that are not subscribed to a set of MB services need not obtain MB control information upon receiving a notification of a change in MB control information for that set of MB services, thereby reducing power consumption and extending battery life. Furthermore, some techniques and apparatuses conserve system overhead and network resources by using a short message indicator in downlink control information to indicate a change in MB control information. 
       FIG.  4    is a diagram illustrating an example of a multicast broadcast control information flow in accordance with various aspects of the present disclosure. As shown in  FIG.  4   , a base station  110  and a UE  120  may communicate with one another. 
     As shown in  FIG.  4   , the base station  110  may transmit MB control information  405  to the UE  120 . The MB control information  405  may include information usable by the UE  120  to receive one or more MB services. For example, the MB control information  405  may indicate a list of G-RNTIs and corresponding MB services, a mapping between MB-QoS flows and G-RNTIs, a mapping between TMGIs and G-RNTIs, a mapping between LCIDs and G-RNTIs, a CORESET configuration for one or more MB services, a set of time domain resources allocated for one or more MB services, a set of frequency domain resources allocated for one or more MB services, or one or more DRX parameters associated with MB communications, among other examples. In some aspects, the UE  120  may monitor for a message that includes MB control information  405  for all MB services provided in a service area of the UE  120  (for example, a coverage area of the base station  110  or one or more neighbor base stations  110 ). Alternatively, the UE  120  may monitor for a message that includes MB control information  405  for only those MB services of interest to the UE  120  or only those MB services to which the UE  120  is subscribed. 
     As further shown, in one MB system design, the MB control information  405  may be carried in an MBCCH (for example, in an MBCCH communication). The MBCCH communication may be scheduled by a PDCCH communication addressed to an MB-RNTI. In another MB system design, the MB control information  405  may be carried in a SIB. The SIB may be scheduled by a PDCCH communication addressed to an SI-RNTI. In another MB system design, the MB control information  405  may be carried in an RRC message (for example, an RRC configuration message or an RRC reconfiguration message, among other examples), such as a unicast RRC message. The RRC message may be scheduled by a PDCCH communication addressed to a C-RNTI. 
     As further shown in  FIG.  4   , the base station  110  may transmit, to the UE  120 , a notification of a change to the MB control information  405 . This notification may be referred to herein as an MB control information change notification  410  or as a change notification  410 . The manner in which the MB control information change notification  410  is transmitted by the base station  110  and received by the UE  120  may depend on an MB system design, such as whether the MB control information  405  is included in an MBCCH communication, a SIB, or an RRC message, among other examples. Additionally or alternatively, the signaling included in the MB control information change notification  410  may depend on the MB system design. In some aspects, the UE  120  may monitor for an MB control information change notification  410  that is triggered by a change to any MB service provided in a service area of the UE  120 . Alternatively, the UE  120  may monitor for an MB control information change notification  410  that is triggered by a change to only those MB services of interest to the UE  120  or only those MB services to which the UE  120  is subscribed. 
     As further shown in  FIG.  4   , the UE  120  may obtain updated MB control information  415 , such as by monitoring for and receiving the updated MB control information  415 , based at least in part on receiving the MB control information change notification  410 . In some aspects, the UE  120  may monitor one or more resources allocated to MB control information  405 / 415  based at least in part on receiving the MB control information change notification  410 . The manner in which the UE  120  obtains updated MB control information  415  may depend on the MB system design. 
     Additional details regarding an MB control information change notification  410  for MB control information  405  included in an MBCCH communication are described below in connection with  FIGS.  5 - 7   . Additional details regarding an MB control information change notification  410  for MB control information  405  included in a SIB are described below in connection with  FIGS.  8  and  9   . Additional details regarding an MB control information change notification  410  for MB control information  405  included in an RRC message are described below in connection with  FIG.  10   . 
       FIG.  5    is a diagram illustrating another example of a multicast broadcast control information flow in accordance with various aspects of the present disclosure. As shown in  FIG.  5   , a base station  110  and a UE  120  may communicate with one another. 
     As shown in  FIG.  5   , the base station  110  may transmit MB control information  505  to the UE  120 . As shown, the MB control information  505  may be carried in an MBCCH (for example, in an MBCCH communication). The MBCCH communication may be scheduled by a PDCCH communication addressed to an MB-RNTI. In the example of  FIG.  5   , the MB system design uses a single MBCCH to carry control information for all MB services that are provided in a service area associated with the MBCCH (for example, a coverage area of the base station  110 ). 
     As further shown in  FIG.  5   , the base station  110  may transmit, to the UE  120 , an MB control information change notification  510 . In the example of  FIG.  5   , where a single MBCCH carries control information for all MB services, there may be a single change notification  515  used for all MB services in the service area, or the MB services in the service area may be partitioned into multiple sets of MB services and a separate change notification  520  (for example, transmitted using a different field in the same channel (for example, the PDCCH) or a same downlink control information (DCI), or transmitted using a different set of time-frequency resources than other change notifications  520 ) may be used for each set of MB services. In some aspects, the base station  110  may group MB services based at least in part on an update cycle associated with MB services, such that MB services with a similar update cycle (for example, that have a similar periodicity to changes in MB control information  505 ) are included in the same set of MB services. 
     For example, the base station  110  may use a single change notification  515  for all MB services. In this example, the base station  110  may trigger transmission of the single change notification  515  based at least in part on a change to any MB service associated with the service area of the base station  110 . In this example, when the UE  120  receives the single change notification  515 , the UE  120  may obtain updated MB control information  525 . For example, the UE  120  may obtain the updated MB control information  525  via the MBCCH, in a similar manner as described above in connection with the MB control information  505 . In some aspects, the UE  120  may read a portion of the MBCCH communication that includes the MB control information  505 / 525  to identify MB control information  505 / 525  associated with one or more MB services to which the UE  120  is subscribed. In some examples, the MB control information  505 / 525  for the MB service(s) to which the UE  120  is subscribed may not have changed from a time prior to the change to the MB control information  505 / 525 , but the UE  120  may still obtain the MB control information  505 / 525  due to this MB system design. In other words, if a single change notification  515  is used for all MB services, the UE  120  may obtain updated MB control information  525  upon receiving the single change notification  515  regardless of whether an MB service to which the UE  120  is subscribed triggered the single change notification  515  (for example, regardless of whether the updated MB control information  525  has changed for an MB service to which the UE  120  is subscribed). 
     As another example, the base station  110  may use separate change notifications  520  for different sets of MB services. In some aspects, each set of MB services is a different subset of all of the MB services in a service area of the base station  110 . In this example, the base station  110  may trigger transmission of a change notification  520  associated with a set of MB services (for example, a set of one or more MB services) based at least in part on a change to one or more MB services included in that set of MB services. In this example, if the UE  120  receives the change notification  520  for the set of MB services, then the UE  120  may obtain updated MB control information  525  only if the UE  120  is subscribed to an MB service included in the set of MB services. In other words, if the UE  120  receives a change notification  520  associated with a set of MB services to which the UE  120  is not subscribed, then the UE  120  may refrain from monitoring for updated MB control information  525  based at least in part on receiving that change notification  520 . In some aspects, the base station  110  may indicate (for example, in a SIB or an RRC message, among other examples) different resources in which different change notifications  520  are scheduled, and the UE  120  may monitor for only the change notification(s)  520  associated with the MB service(s) to which the UE  120  is subscribed. In this way, power consumption of the UE  120  may be reduced. 
     In some aspects, change notifications  520  for different sets of MB services may be transmitted or monitored with different periodicities. For example, a set of MB services with a longer update cycle may be associated with a change notification  520  with a longer periodicity, and a set of MB services with a shorter update cycle may be associated with a change notification  520  with a shorter periodicity. When the change notifications  520  for different set of services or different MBCCHs are transmitted on different channels, the change notifications  520  can be transmitted with different periodicities according to a service update cycle. When the change notifications  520  for different set of services or different MBCCHs are transmitted on the same channel, the change notifications  520  can be sent with a shorter periodicity, and the UE  120  can monitor the change notifications  520  based on different periodicities (for example, configured by the base station  110 ) according to the service update cycle. This may conserve UE battery power while also assisting UEs  120  with receiving updated MB control information  525 . 
       FIG.  6    is a diagram illustrating another example of a multicast broadcast control information flow in accordance with various aspects of the present disclosure. As shown in  FIG.  6   , a base station  110  and a UE  120  may communicate with one another. In the example of  FIG.  6   , the MB system design includes multiple MBCCHs, rather than a single MBCCH described above in connection with  FIG.  5   . In some aspects, each MBCCH, of the multiple MBCCHs, may occupy a different set of time-frequency resources than every other MBCCH of the multiple MBCCHs. For example, different MBCCHs may have different resource allocations (for example, within a PDSCH). Additionally or alternatively, each MBCCH may be associated with a different set of MB services (for example, a different subset of all of the MB services in a service area of the base station  110 ). For example, each MBCCH may carry MB control information for a different set of MB services. In some aspects, different MBCCHs may be associated with different transmission configurations, such as different repetition periods, different modification periods, or different on durations for MBCCH scheduling, among other examples. 
     As shown in  FIG.  6   , the base station  110  may transmit a first MBCCH communication  605 , via a first MBCCH (shown as MBCCH 1), that includes MB control information for a first set of MB services (shown as MB service set 1). As further shown, the base station  110  may transmit a second MBCCH communication  610 , via a second MBCCH (shown as MBCCH 2), that includes MB control information for a second set of MB services (shown as MB service set 2). As further shown, the base station  110  may transmit a third MBCCH communication  615 , via a third MBCCH (shown as MBCCH 3), that includes MB control information for a third set of MB services (shown as MB service set 3). Three MBCCHs associated with a corresponding three MB service sets are shown in  FIG.  6    as an example. In practice, a different number of MBCCHs and MB services sets may be used. As further shown in  FIG.  6   , the UE  120  may be subscribed to an MB service included in MB service set 1 and an MB service included in MB service set 3, and may not be subscribed to any MB services in MB service set 2. The first MBCCH communication  605 , the second MBCCH communication  610 , and the third MBCCH communication  615  may be scheduled by a PDCCH communication addressed to an MB-RNTI (for example, a single PDCCH communication for all of the MBCCHs or a different PDCCH communication for each MBCCH). 
     In some aspects, the base station  110  may indicate, to the UE  120 , a set of MB services corresponding to an MBCCH in a configuration message (for example, an RRC message). For example, the configuration message may indicate each MBCCH and a respective set of MB services corresponding to each MBCCH. Additionally or alternatively, the UE  120  can indicate the MB service(s) of interest to the base station  110 , and the base station  110  can signal, to the UE  120 , the corresponding MBCCH(s) to monitor based on those MB service(s) of interest. In this way, power consumption of the UE  120  may be reduced by monitoring MB control information for only the MB services in which the UE  120  is interested or is subscribed. 
     In some aspects, different MBCCHs may be associated with different MB-RNTIs. In this example, a PDCCH communication, that schedules an MBCCH communication associated with a specific MB-RNTI, may be addressed to the specific MB-RNTI. Furthermore, PDCCH communications that schedule MBCCH communications for different MBCCHs may be addressed to different MB-RNTIs. In this example, different MBCCHs may use overlapping scheduling windows, may use the same hybrid automatic repeat request (HARQ) process or the same set of HARQ processes, and may use the same LCD or the same set of LCIDs. 
     Alternatively, different MBCCHs may be associated with (for example, may share) the same MB-RNTI. For example, a PDCCH communication, that schedules multiple MBCCH communications associated with the same MB-RNTI, may be addressed to the same MB-RNTI. In this example, different MBCCHs that share an MB-RNTI may be associated with different non-overlapping scheduling windows. For example, a first set of time-frequency resources used for a first MBCCH may be different from a second set of time-frequency resources used for a second MBCCH that shares an MB-RNTI with the first MBCCH. Additionally or alternatively, a first PDCCH communication that schedules MBCCH communications for a first MBCCH may occur in a first set of time-frequency resources, and a second PDCCH communication that schedules MBCCH communications for a second MBCCH, that shares an MB-RNTI with the first MBCCH, may occur in a second set of time-frequency resources. In this example, the UE  120  may differentiate the MBCCHs based at least in part on a scheduling window used for an MBCCH. 
     Additionally or alternatively, different MBCCHs that share an MB-RNTI may be associated with different HARQ processes (and different HARQ process identifiers). For example, a first HARQ process identifier or a first set of HARQ process identifiers may be used for a first MBCCH, and a second HARQ process identifier or a second set of HARQ process identifiers may be used for a second MBCCH that shares an MB-RNTI with the first MBCCH. In this example, the different MBCCHs may use an overlapping scheduling window (and may also use the same LCD, in some aspects), and the UE  120  may differentiate the MBCCHs based at least in part on a HARQ process identifier used for an MBCCH. 
     Additionally or alternatively, different MBCCHs that share an MB-RNTI may be associated with different LCIDs. For example, a first LCID or a first set of LCIDs may be used for a first MBCCH, and a second LCID or a second set of LCIDs may be used for a second MBCCH that shares an MB-RNTI with the first MBCCH. In this example, the different MBCCHs may use an overlapping scheduling window (and may use the same HARQ process identifier(s), in some aspects), and the UE  120  may differentiate the MBCCHs based at least in part on an LCID used for an MBCCH. 
     In some aspects, different MBCCHs may correspond to different bandwidth part configurations. For example, different sets of MB services may be provided in different bandwidth parts (or for different bandwidth part configurations). In some aspects, a first set of MB services may be provided in a bandwidth part with a wider bandwidth (for example, a first set of MB services that has more content), and a second set of MB services may be provided in a bandwidth part with a narrower bandwidth (for example, a second set of MB services that has less content). 
     As further shown in  FIG.  6   , the base station  110  may transmit, to the UE  120 , an MB control information change notification  620 . In the example of  FIG.  6   , where different MBCCHs carry control information for different sets of MB services, the base station  110  may use a separate change notification  620  for each MBCCH. For example, the base station  110  may transmit each change notification  620  using a different field in the same channel (for example, the PDCCH) or a same downlink control information (DCI), or using a different set of time-frequency resources than other change notifications  620 . In this example, the base station  110  may trigger transmission of a change notification  620  associated with a set of MB services (or an MBCCH that carries control information for that set of MB services) based at least in part on a change to one or more MB services included in that set of MB services. In this example, if the UE  120  receives the change notification  620  for the set of MB services, then the UE  120  may obtain updated MB control information only if the UE  120  is subscribed to an MB service included in the set of MB services. 
     For example, as shown in  FIG.  6   , the base station  110  may transmit a first change notification (shown as CN 1 ) for MB service set 1 and may transmit a second change notification (shown as CN 2 ) for MB service set 2. The first change notification may indicate that MB control information for MB service set 1 has changed (for example, from a time at which prior MB control information for MB service set 1 was transmitted). Similarly, the second change notification may indicate that MB control information for MB service set 2 has changed. The MB control information for MB service set 3 may not have changed since a prior time at which a change notification  620  for MB service set 3 was scheduled to be transmitted, and so the base station  110  may refrain from transmitting a change notification  620  for MB service set 3. Alternatively, the base station  110  may transmit a third change notification (shown as CN3) for MB service set 3, and the third change notification may indicate that MB control information for MB service set 3 has not changed. 
     In some aspects, the base station  110  may indicate, to the UE  120 , one or more resources that carry a change notification  620 . The UE  120  may monitor the one or more resources based at least in part on receiving the indication. In some aspects, the base station  110  may indicate different sets of resources for different change notifications  620  (for example, corresponding to different MB service sets or different MBCCHs), and the UE  120  may monitor for only the change notifications  620  associated with an MB service to which the UE  120  is subscribed. 
     As further shown, the UE  120  may obtain updated MB control information  625  for MB service set 1, such as by monitoring one or more resources of MBCCH 1 for MB control information  625 . In the example of  FIG.  6   , the UE  120  may obtain the updated MB control information  625  for MB service set 1 because the UE  120  is subscribed to one or more MB services included in MB service set 1 and because the UE  120  received a change notification  620  for MB service set 1. 
     As further shown, the UE  120  may refrain from obtaining updated MB control information  630  for MB service set 2. In the example of  FIG.  6   , the UE  120  may refrain from obtaining the updated MB control information  630  for MB service set 2 even if the UE  120  receives a change notification  620  for MB service set 2 because the UE  120  is not subscribed any MB services included in MB service set 2. 
     As further shown, the UE  120  may refrain from obtaining MB control information  635  for MB service set 3. In the example of  FIG.  6   , the UE  120  may refrain from obtaining the MB control information  635  for MB service set 3 even if the UE  120  is subscribed to one or more MB services included in MB service set 3 because the UE  120  did not receive a change notification  620  for MB service set 3 (or received a change notification  620  indicating that MB control information  635  for MB service set 3 has not changed). 
     In some aspects, the base station  110  may indicate, to the UE  120 , addition of a new MB service to a service area of the base station  110 . In some aspects, the UE  120  may monitor for updated MB control information associated with the new MB service. In some aspects, the base station  110  may indicate an MBCCH or an MB service group for the new MB service, and the UE  120  may monitor that MBCCH to obtain MB control information for the new MB service. In this way, the UE  120  may reduce power consumption as compared to monitoring for all MB control information (for example, on all MBCCHs) for the new MB service. 
       FIG.  7    is a diagram illustrating an example of a multicast broadcast control information change notification in accordance with various aspects of the present disclosure.  FIG.  7    shows an example of a change notification  705  carried in a PDCCH communication. The change notification  705  shown in  FIG.  7    may be used to notify a UE  120  of a change to MB control information for an MB system design that uses one or more MBCCHs, as described above in connection with  FIGS.  5  and  6   . As shown in  FIG.  7   , in some aspects, a change notification  705  may be included in a PDCCH communication  710  (also referred to as DCI). In some aspects, the PDCCH communication  710  may be addressed to an MB-RNTI, as shown in  FIG.  7   . 
     As further shown, the PDCCH communication  710  may include an indication of whether the PDCCH communication  710  includes scheduling information for the MBCCH and not a notification of a change (shown as a bit value of 01 in a bit field), whether the PDCCH communication  710  includes a notification of a change and not scheduling information (shown as a bit value of 10 in the bit field), or whether the PDCCH communication  710  includes both scheduling information and a notification of a change (shown as a bit value of 11 in the bit field). In some aspects, the change notification  705  may be referred to as a short message, and the PDCCH communication  710  may indicate whether the PDCCH communication  710  includes the short message (for example, using a short message indicator). The scheduling information for the MBCCH may indicate, for example, a resource allocation for an MBCCH communication (for example, a set of time-frequency resources), a modulation and coding scheme for the MBCCH communication, or other scheduling information for the MBCCH communication. 
     In some aspects, the change notification  705  (the short message) may include a bitmap (for example, in a field of the PDCCH communication  710  that carries the change notification  705 ). Different bits of the bitmap may correspond to different MBCCHs or different set of MB services, which may be associated with different sets of MB services, as described above in connection with  FIG.  6   . A value of a bit in the bitmap may represent a change notification  705  corresponding to an MBCCH or a set of MB services associated with that bit. For example, a first value of a bit (for example, 0) may indicate that MB control information of an MBCCH or a set of MB services, corresponding to the bit, has not changed, and a second value of the bit (for example, 1) may indicate that MB control information of the MBCCH or the set of MB services has changed. In example bitmap  715  of  FIG.  7   , a bitmap value of 110 indicates that MB control information for MBCCH 1 or a first set of MB services has changed (represented by a 1 in the first bit in the bitmap), that MB control information for MBCCH 2 or a second set of MB services has changed (represented by a 1 in the second bit in the bitmap), and that MB control information for MBCCH 3 or a third set of MB services has not changed (represented by a 0 in the third bit in the bitmap), which corresponds to the example of  FIG.  6   . The bitmap  715  may be transmitted in the PDCCH communication  710 . 
     In some aspects, the bitmap may include a bit to indicate whether a new MB service has been added to a service area of the base station  110 . In this example, a first value of the bit (for example, 0) may indicate that a new MB service has not been added, and a second value of the bit (for example, 1) may indicate that a new MB service has been added. In example bitmap  720  of  FIG.  7   , a bitmap value of 1101 indicates that MB control information for MBCCH 1 has changed (represented by a 1 in the first bit in the bitmap), that MB control information for MBCCH 2 has changed (represented by a 1 in the second bit in the bitmap), that MB control information for MBCCH 3 has not changed (represented by a 0 in the third bit in the bitmap), and that a new MB service has been added (represented by a 1 in the fourth bit in the bitmap). The bitmap  720  may be transmitted in the PDCCH communication  710 . 
     Thus, if a service area includes NMB service groups (for example, N sets of MB services), then the bitmap in the short message may include N bits in some aspects, where each of the N bits corresponds to a different set of MB services of the N sets of MB services. Alternatively, the bitmap may include N+1 bits, with one bit for each set of MB services of the N sets of MB services and an additional bit for a new MB service indication. 
     In some aspects, the base station  110  may indicate, to the UE  120 , one or more resources that carry the PDCCH communication  710 . The UE  120  may monitor the one or more resources based at least in part on receiving the indication of the one or more resources that carry the PDCCH communication  710 . Additionally or alternatively, the base station  110  may indicate a CORESET for the PDCCH communication  710  or a bandwidth part for the PDCCH communication  710 , among other examples. In some aspects, a slot for monitoring the PDCCH communication  710  (for example, the change notification  705 ) may overlap with one or more slots for MBCCH scheduling. In some aspects, the slot for monitoring the PDCCH communication  710  may be a first slot in an MBCCH modification period associated with one or more MBCCHs (for example, a period of time during which MB control information cannot be changed). Alternatively, the base station  110  may indicate (for example, in a SIB or in an RRC message) a slot offset for monitoring the PDCCH communication  710  within the MBCCH modification period. In some aspects, the PDCCH communication  710  may be in the same bandwidth part as an MBCCH PDSCH (for example, the PDSCH used to convey the MBCCH) communication scheduled by the PDCCH communication  710 . Alternatively, the PDCCH communication  710  may be in a different bandwidth part than an MBCCH PDSCH communication scheduled by the PDCCH communication  710 . 
     Although  FIG.  7    shows the change notification  705  being included in a PDCCH communication addressed to an MB-RNTI, which uses a short message indicator to conserve signaling overhead, in some aspects, the change notification  705  may be included in a message addressed to a different RNTI than the MB-RNTI (and other than a paging RNTI (P-RNTI), in some aspects). For example, the change notification  705  may be included in a message addressed to an MB notification RNTI (MB-N-RNTI). In this example, the PDCCH communication  710  need not include the short message indicator (for example, may include scheduling information without including the change notification  705 ). In other words, the PDCCH addressed to the MB-RNTI may be dedicated to scheduling the MBCCH while the PDCCH addressed to the MB-N-RNTI may be dedicated for a short message with change notifications  705  for MB services. 
       FIG.  8    is a diagram illustrating another example of a multicast broadcast control information flow in accordance with various aspects of the present disclosure. As shown in  FIG.  8   , a base station  110  and a UE  120  may communicate with one another. As further shown, the base station  110  may transmit MB control information  805  to the UE  120 . As shown, the MB control information  805  may be carried in a SIB. The SIB may be scheduled by a PDCCH communication addressed to an SI-RNTI. 
     As further shown, the base station  110  may transmit, to the UE  120 , an MB control information change notification  810  (also referred to as a change notification  810 ). The MB control information change notification  810  may be indicated in a field or a message that is different from a field or a message used to indicate a change to system information (for example, one or more SIBs) other than the SIB carrying the MB control information  805 . In this way, UEs  120  that are not interested in MB services do not need to reacquire a SIB that has been modified due to a change in the MB control information  805 . In the example of  FIG.  8   , where a SIB carries control information for all MB services, there may be a single change notification  815  used for all MB services in the service area, or the MB services in the service area may be partitioned into multiple sets of MB services and a separate change notification  820  (for example, transmitted using a different field or a different set of time-frequency resources than other change notifications  820 ) may be used for each set of MB services. 
     For example, the base station  110  may use a single change notification  815  for all MB services. In this example, the base station  110  may trigger transmission of the single change notification  815  based at least in part on a change to any MB service associated with the service area of the base station  110 . In this example, when the UE  120  receives the single change notification  815 , the UE  120  may obtain updated MB control information  825 . In some aspects, the UE  120  may read a portion of the SIB that includes the MB control information  805 / 825  to identify MB control information  805 / 825  associated with one or more MB services to which the UE  120  is subscribed. In some examples, the MB control information  805 / 825  for the MB service(s) to which the UE  120  is subscribed may not have changed from a time prior to the change to the MB control information  805 / 825 , but the UE  120  may still obtain the MB control information  805 / 825  due to this MB system design. In other words, if a single change notification  815  is used for all MB services, the UE  120  may obtain updated MB control information  825  upon receiving the single change notification  815  regardless of whether an MB service to which the UE  120  is subscribed triggered the change notification  815  (for example, regardless of whether the updated MB control information  825  has changed for an MB service to which the UE  120  is subscribed). 
     As another example, the base station  110  may use separate change notifications  820  for different sets of MB services. In some aspects, each set of MB services is a different subset of all of the MB services in a service area of the base station  110 . In this example, the base station  110  may trigger transmission of a change notification  820  associated with a set of MB services (for example, a set of one or more MB services) based at least in part on a change to one or more MB services included in that set of MB services. In this example, if the UE  120  receives the change notification  820  for the set of MB services, then the UE  120  may obtain updated MB control information  825  only if the UE  120  is subscribed to an MB service included in the set of MB services. In other words, if the UE  120  receives a change notification  820  associated with a set of MB services to which the UE  120  is not subscribed, then the UE  120  may refrain from monitoring for updated MB control information  825  based at least in part on receiving that change notification  820 . Additionally or alternatively, the base station  110  may indicate (for example, in an RRC message) different resources in which different change notifications  820  are scheduled, and the UE  120  may monitor for only the change notification(s)  820  associated with the MB service(s) to which the UE  120  is subscribed. In this way, power consumption of the UE  120  may be reduced. 
       FIG.  9    is a diagram illustrating another example of a multicast broadcast control information change notification in accordance with various aspects of the present disclosure.  FIG.  9    shows an example of a change notification  905  carried in a PDCCH communication. The change notification  905  shown in  FIG.  9    may be used to notify a UE  120  of a change to MB control information for an MB system design that uses a SIB, as described above in connection with  FIG.  8   . As shown in  FIG.  9   , in some aspects, a change notification  905  may be included in a PDCCH communication  910  (also referred to as DCI) that is addressed to a paging RNTI (P-RNTI). In some aspects, the base station  110  may indicate a paging occasion or a paging frame in which the UE  120  is to monitor for the PDCCH communication  910  (or a PDCCH communication  915 ). 
     As further shown, the PDCCH communication  910  may include at least one of an indication  920  of whether there is a modification to system information other than a set of SIBs (shown as SIB6, SIB7, SIB8, and SIBx) that includes the SIB carrying the MB control information (shown as SIBx), an indication (for example, a change notification  905 ) of whether there is a modification to the SIB carrying the MB control information, or a combination thereof. For example, a first bit in a short message indication of the PDCCH communication  910  (shown as bit 1) may indicate whether there is a modification to system information other than a set of SIBs (shown as SIB6, SIB7, SIB8, and SIBx) that includes the SIB carrying the MB control information (shown as SIBx). Additionally or alternatively, a second bit in a short message indication of the PDCCH communication  910  (shown as bit 2) may indicate whether the short message is associated with an emergency message, such as an Earthquake and Tsunami Warning System (ETWS) message or a Commercial Mobile Alert System (CMAS) message. Additionally or alternatively, a third bit in a short message indication of the PDCCH communication  910  (shown as bit 3) may indicate whether there is a modification to the SIB carrying the MB control information (shown as SIBx). In some aspects, one or more bits (shown as bits 4 through 8) of the short message indication in the PDCCH communication  910  may be reserved. 
     In some aspects, if bit 1 (the bit that indicates whether there is a modification to system information other than a set of SIBs that includes the SIB carrying the MB control information) is set to a first value (for example, 0), then a UE  120  may obtain updated system information regardless of whether that UE  120  is interested in or subscribed to MB services. However, if there is an update to MB services but not another SIB (for example, other than SIB6, SIB7, SIBS, or SIBx), then bit 1 may be set to a second value (for example, 1), and a UE  120  that is not interested in or subscribed to MB services may refrain from obtaining system information. In this way, UEs  120  that are not interested in or subscribed to MB services may conserve power by refraining from monitoring for SIBx (for example, based at least in part on a value of bit 1) and may still obtain updates to system information other than SIBx. 
     In some aspects, if bit 3 (the bit that indicates whether there is a modification to the SIB carrying the MB control information) has a first value (for example, 0), then this may indicate that there is not a modification to the SIB carrying the MB control information (or that the MB control information has not changed). In this example, a UE  120  subscribed to or interested in receiving MB services may refrain from obtaining the SIB. If bit 3 has a second value (for example, 1), then this may indicate that there is a modification to the SIB carrying the MB control information (or that the MB control information has changed). In this example, a UE  120  subscribed to or interested in receiving MB services may obtain the SIB (for example, to obtain updated MB control information). 
     In some aspects, the PDCCH communication  910  may include an indication of whether there is a modification to a specific set of MB services (for example, when all MB services in a service area are partitioned into multiple sets of MB services). In this example, a bit in the short message may indicate whether there is a modification to MB control information associated with a first set of MB services, another bit in the short message may indicate whether there is a modification to MB control information associated with a second set of MB services, and so on. In this example, one or more of the reserved bits (shown as bits 4 through 8) may be used to indicate whether a specific set of MB services is associated with updated MB control information. 
     Additionally or alternatively, the PDCCH communication  910  may include an indication of whether a new MB service has been added to the available MB services in a service area. For example, a bit of the short message may indicate whether a new MB service has been added. A first value of the bit may indicate that a new MB service has not been added, and a second value of the bit may indicate that a new MB service has been added. In this example, one or more of the reserved bits (shown as bits 4 through 8) may be used to indicate whether a new MB service has been added. 
     In some aspects, a PDCCH communication  910  addressed to a P-RNTI may include an indication of whether there is a modification to the SIB carrying the MB control information (shown as bit 3), and a separate paging message (for example, corresponding to the PDCCH communication  910 , (for example, a PDSCH communication scheduled by the PDCCH communication  910 ) may indicate a specific set of MB services associated with a change to MB control information. For example, the paging message may include a bitmap described above in connection with  FIG.  7    (for example, bitmap  715  or bitmap  720 ). 
     In some aspects, a change notification may be included in a PDCCH communication that is addressed to an RNTI other than a P-RNTI and an SI-RNTI, such as an MB-N-RNTI (sometimes referred to as an M-N-RNTI). This PDCCH communication may include multiple bits for a change notification, and each bit may indicate whether a corresponding set of MB services is associated with a change in MB control information. Additionally or alternatively, this PDCCH communication may include an indication of whether a new MB service has been added, as described elsewhere herein. 
     When the change notification is included in a PDCCH communication that is addressed to an RNTI other than a P-RNTI and an SI-RNTI, a PDCCH communication  915  addressed to a P-RNTI need not include an indication  925  of whether there is a modification to the SIB carrying the MB control information (shown as SIBx). However, as shown, the PDCCH communication  915  may include an indication  925  of whether there is a modification to system information other than a set of SIBs (shown as SIB6, SIB7, SIB8, and SIBx) that includes the SIB carrying the MB control information (shown as SIBx). For example, a first bit in a short message indication of the PDCCH communication  915  (shown as bit 1) may indicate whether there is a modification to system information other than a set of SIBs (shown as SIB6, SIB7, SIB8, and SIBx) that includes the SIB carrying the MB control information (shown as SIBx). Additionally or alternatively, a second bit in a short message indication of the PDCCH communication  910  (shown as bit 2) may indicate whether the short message is associated with an emergency message, such as an ETWS message or a CMAS message. In some aspects, one or more bits (shown as bits 3 through 8) of the short message indication in the PDCCH communication  915  may be reserved. 
       FIG.  10    is a diagram illustrating another example of a multicast broadcast control information flow in accordance with various aspects of the present disclosure. As shown in  FIG.  10   , a base station  110  and a UE  120  may communicate with one another. As further shown, the base station  110  may transmit MB control information  1005  to the UE  120 . As shown, the MB control information  1005  may be carried in an RRC message, such as a unicast RRC message. The RRC message may be scheduled by a PDCCH communication addressed to a C-RNTI. 
     As further shown, the base station  110  may transmit, to the UE  120 , an MB control information change notification  1010  (also referred to as a change notification  1010 ). In the example of  FIG.  10   , where an RRC message carries control information  1005  for all MB services, there may be a single change notification  1015  used for all MB services in the service area, or the MB services in the service area may be partitioned into multiple sets of MB services and a separate change notification  1020  (for example, transmitted using a different field or a different set of time-frequency resources than other change notifications  1020 ) may be used for each set of MB services. 
     For example, the base station  110  may use a single change notification  1015  for all MB services. In this example, the base station  110  may trigger transmission of the single change notification  1015  based at least in part on a change to any MB service associated with the service area of the base station  110 . In this example, when the UE  120  receives the single change notification  1015 , the UE  120  may obtain updated MB control information  1025 . For example, the UE  120  may obtain a new RRC message (for example, via an RRC reconfiguration message or via an RRC release procedure and RRC connection establishment procedure). In some aspects, the UE  120  may read a portion of the RRC message that includes the MB control information  1005 / 1025  to identify MB control information  1005 / 1025  associated with one or more MB services to which the UE  120  is subscribed. In some examples, the MB control information  1005 / 1025  for the MB service(s) to which the UE  120  is subscribed may not have changed from a time prior to the change to the MB control information  1005 / 1025 , but the UE  120  may still obtain the MB control information  1005 / 1025  due to this MB system design. In other words, if a single change notification  1015  is used for all MB services, the UE  120  may obtain updated MB control information  1025  upon receiving the single change notification  1015  regardless of whether an MB service to which the UE  120  is subscribed triggered the change notification  1015  (for example, regardless of whether the updated MB control information  1025  has changed for an MB service to which the UE  120  is subscribed). 
     As another example, the base station  110  may use separate change notifications  1020  for different sets of MB services. In some aspects, each set of MB services is a different subset of all of the MB services in a service area of the base station  110 . In this example, the base station  110  may trigger transmission of a change notification  1020  associated with a set of MB services (for example, a set of one or more MB services) based at least in part on a change to one or more MB services included in that set of MB services. In this example, if the UE  120  receives the change notification  1020  for the set of MB services, then the UE  120  may obtain updated MB control information  1025  only if the UE  120  is subscribed to an MB service included in the set of MB services. In other words, if the UE  120  receives a change notification  1020  associated with a set of MB services to which the UE  120  is not subscribed, then the UE  120  may refrain from monitoring for updated MB control information  1025  based at least in part on receiving that change notification  1020 . Additionally or alternatively, the base station  110  may indicate different resources in which different change notifications  1020  are scheduled, and the UE  120  may monitor for only the change notification(s)  1020  associated with the MB service(s) to which the UE  120  is subscribed. In this way, power consumption of the UE  120  may be reduced. 
     The change notification  1010  may be included in dedicated RRC signaling, in a paging message, or in a short message indication, among other examples. In some aspects, a message used to transmit the change notification  1010  may depend on an RRC mode (sometimes referred to as an RRC state) of the UE  120 , such as an RRC connected mode, an RRC idle mode, or an RRC inactive mode. For example, a UE  120  in an RRC connected mode may receive a change notification  1010  via dedicated RRC signaling with the base station  110 . For a UE  120  in an RRC inactive mode, the base station  110  may transmit the change notification  1010  to the UE  120  using a radio access network (RAN) paging message, a short message indication, or a PDCCH direct indication (such as a PDCCH direct indication used in eMTC communications), among other examples. For a UE  120  in an RRC idle mode, the base station  110  may transmit the change notification  1010  to the UE  120  using a RAN-initiated paging message (similar to a message used in eMTC to alert UEs  120  of a change to access barring), a short message indication, or a PDCCH direct indication. When a UE  120  in an RRC idle mode or an RRC inactive mode receives the change notification  1010 , the UE  120  may enter an RRC connected mode to receive the updated MB control information  1025  via dedicated RRC signaling. 
     In some aspects, the MB control information  1005 / 1025  is associated with a group of cells. In this example, the base station  110  may indicate the group of cells, for which the MB control information  1005 / 1025  is valid, to the UE  120 . If the UE  120  performs a cell reselection while in an RRC idle mode, the UE  120  need not enter an RRC connected mode to obtain updated MB control information  1025  if the cell reselected by the UE  120  is in the group of cells, thereby conserving power of the UE  120 . However, if the UE  120  selects a cell that is not included in the group of cells, then the UE  120  may enter the RRC connected mode to obtain the MB control information  1005 / 1025  via dedicated RRC signaling. 
       FIG.  11    is a flowchart illustrating an example process  1100  performed, for example, by a UE in accordance with various aspects of the present disclosure. The example process  1100  is an example where the UE (for example, UE  120 ) performs operations associated with monitoring MB control information. 
     As shown in  FIG.  11   , in some aspects, the process  1100  may include receiving a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in an MBCCH scheduled by a PDCCH communication addressed to an MB-RNTI (block  1110 ). For example, the UE (for example, using receive processor  258 , controller/processor  280 , or memory  282 , among other examples) may receive a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, as described above. In some aspects, the MB control information is included in an MBCCH scheduled by a PDCCH communication addressed to an MB-RNTI. 
     As further shown in  FIG.  11   , in some aspects, the process  1100  may include monitoring one or more resources of the MBCCH to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information (block  1120 ). For example, the UE (for example, using receive processor  258 , controller/processor  280 , or memory  282 , among other examples) may monitor one or more resources of the MBCCH to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information, as described above. 
     The process  1100  may include additional aspects, such as any single aspect or any combination of aspects described below or in connection with one or more other processes described elsewhere herein. 
     In a first aspect, the MBCCH is a single MBCCH used to transmit MB control information for all MB services associated with a service area of the UE. 
     In a second aspect, alone or in combination with the first aspect, the notification is triggered based at least in part on a change to any MB service associated with a service area of the UE. 
     In a third aspect, alone or in combination with one or more of the first and second aspects, the single MBCCH is associated with multiple sets of MB services and a separate MB control information change notification is associated with each of the multiple sets of MB services. 
     In a fourth aspect, alone or in combination with one or more of the first through third aspects, the process  1100  includes receiving an MB control information change notification associated with an MB service to which the UE is not subscribed; and refraining from monitoring for updated MB control information based at least in part on receiving the MB control information change notification associated with the MB service to which the UE is not subscribed. 
     In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the MBCCH is one of multiple MBCCHs, each of the multiple MBCCHs being associated with a different set of MB services. 
     In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, a separate MB control information change is associated with each of the multiple MBCCHs. 
     In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the process  1100  includes receiving an MB control information change notification associated with an MBCCH that is associated with a set of MB services to which the UE is not subscribed; and refraining from monitoring for updated MB control information based at least in part on receiving the MB control information change notification associated with the MBCCH that is associated with a set of MB services to which the UE is not subscribed. 
     In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, at least two MBCCHs of the multiple MBCCHs are associated with a same MB-RNTI. 
     In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, different MBCCHs, of the at least two MBCCHs that are associated with the same MB-RNTI, are associated with different non-overlapping scheduling windows, different hybrid automatic repeat request processes, different logical channel identifiers, or a combination thereof. 
     In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, at least two MBCCHs of the multiple MBCCHs are associated with different MB-RNTIs. 
     In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, at least two MBCCHs of the multiple MBCCHs correspond to different bandwidth part configurations. 
     In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, the process  1100  includes receiving a configuration message that indicates respective sets of MB services corresponding to each of the multiple MBCCHs; and monitoring the MBCCH based at least in part on the configuration message. 
     In a thirteenth aspect, alone or in combination with one or more of the first through twelfth aspects, the process  1100  includes receiving an indication of a new MB service; and monitoring the one or more resources of the MBCCH to receive the updated MB control information based at least in part on receiving the indication of the new MB service. 
     In a fourteenth aspect, alone or in combination with one or more of the first through thirteenth aspects, the notification of the change to the MB control information is included in the PDCCH communication addressed to the MB-RNTI. 
     In a fifteenth aspect, alone or in combination with one or more of the first through fourteenth aspects, the PDCCH communication addressed to the MB-RNTI includes an indication of whether the PDCCH communication includes scheduling information for the MBCCH and not the notification of the change, includes the notification of the change and not the scheduling information, or includes both the scheduling information and the notification of the change. 
     In a sixteenth aspect, alone or in combination with one or more of the first through fifteenth aspects, the notification of the change includes a bitmap, and different bits of the bitmap correspond to different MBCCHs associated with different sets of MB services or to different sets of MB services in a single MBCCH. 
     In a seventeenth aspect, alone or in combination with one or more of the first through sixteenth aspects, the bitmap includes a bit to indicate a new MB service. 
     In an eighteenth aspect, alone or in combination with one or more of the first through seventeenth aspects, the process  1100  includes receiving an indication of one or more resources that carry the notification of the change to the MB control information; and monitoring the one or more resources that carry the notification of the change to the MB control information. 
     In a nineteenth aspect, alone or in combination with one or more of the first through eighteenth aspects, the notification of the change to the MB control information is received by the UE in a message addressed to a different RNTI than the MB-RNTI to which the PDCCH communication is addressed. 
     Although  FIG.  11    shows example blocks of the process  1100 , in some aspects, the process  1100  may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in  FIG.  11   . Additionally or alternatively, two or more of the blocks of the process  1100  may be performed in parallel. 
       FIG.  12    is a flowchart illustrating an example process  1200  performed, for example, by a UE in accordance with various aspects of the present disclosure. The example process  1200  is an example where the UE (for example, UE  120 ) performs operations associated with monitoring MB control information. 
     As shown in  FIG.  12   , in some aspects, the process  1200  may include receiving a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in a SIB scheduled by a PDCCH communication addressed to an SI-RNTI (block  1210 ). For example, the UE (for example, using receive processor  258 , controller/processor  280 , or memory  282 , among other examples) may receive a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, as described above. In some aspects, the MB control information is included in a SIB scheduled by a PDCCH communication addressed to an SI-RNTI. 
     As further shown in  FIG.  12   , in some aspects, the process  1200  may include monitoring the SIB to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information (block  1220 ). For example, the UE (for example, using receive processor  258 , controller/processor  280 , or memory  282 , among other examples) may monitor the SIB to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information, as described above. 
     The process  1200  may include additional aspects, such as any single aspect or any combination of aspects described below or in connection with one or more other processes described elsewhere herein. 
     In a first aspect, the notification of the change to the MB control information is included in a PDCCH communication addressed to a P-RNTI. 
     In a second aspect, alone or in combination with the first aspect, the PDCCH communication addressed to the P-RNTI includes at least one of an indication of whether there is a modification to system information other than a set of SIBs that includes the SIB carrying the MB control information, an indication of whether there is a modification to the SIB carrying the MB control information, or a combination thereof. 
     In a third aspect, alone or in combination with one or more of the first and second aspects, the process  1200  includes monitoring the SIB to receive the updated MB control information based at least in part on a value of a bit, in the PDCCH communication addressed to the P-RNTI, that indicates whether there is a modification to the SIB. 
     In a fourth aspect, alone or in combination with one or more of the first through third aspects, the PDCCH communication addressed to the P-RNTI includes at least one of an indication of whether there is a modification to a specific set of MB services, an indication of a new MB service, or a combination thereof. 
     In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the PDCCH communication addressed to the P-RNTI includes an indication of whether there is a modification to the SIB, and a paging message corresponding to the PDCCH communication indicates a specific set of MB services associated with the notification of the change to the MB control information. 
     In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the notification of the change to the MB control information is included in a PDCCH communication addressed to an RNTI other than a paging RNTI and the SI-RNTI. 
     In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the PDCCH communication addressed to the RNTI other than the paging RNTI and the SI-RNTI includes at least one of: multiple bits, wherein different bits indicate a change to MB control information for different sets of MB services, an indication of a new MB service, or a combination thereof. 
     In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, a PDCCH communication addressed to a paging RNTI includes an indication of whether there is a modification to system information other than a set of SIBs that includes the SIB that carries the MB control information. 
     Although  FIG.  12    shows example blocks of the process  1200 , in some aspects, the process  1200  may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in  FIG.  12   . Additionally or alternatively, two or more of the blocks of the process  1200  may be performed in parallel. 
       FIG.  13    is a flowchart illustrating an example process  1300  performed, for example, by a UE in accordance with various aspects of the present disclosure. The example process  1300  is an example where the UE (for example, UE  120 ) performs operations associated with monitoring MB control information. 
     As shown in  FIG.  13   , in some aspects, the process  1300  may include receiving a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in a unicast RRC message scheduled by a PDCCH communication addressed to a C-RNTI (block  1310 ). For example, the UE (for example, using receive processor  258 , controller/processor  280 , or memory  282 , among other examples) may receive a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, as described above. In some aspects, the MB control information is included in a unicast RRC message scheduled by a PDCCH communication addressed to a C-RNTI. 
     As further shown in  FIG.  13   , in some aspects, the process  1300  may include monitoring the unicast RRC message to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information (block  1320 ). For example, the UE (for example, using receive processor  258 , controller/processor  280 , or memory  282 , among other examples) may monitor the unicast RRC message to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information, as described above. 
     The process  1300  may include additional aspects, such as any single aspect or any combination of aspects described below or in connection with one or more other processes described elsewhere herein. 
     In a first aspect, the notification of the change is indicated in at least one of: dedicated RRC signaling, a paging message, a short message indication, or a combination thereof. 
     In a second aspect, alone or in combination with the first aspect, the MB control information includes an indication of a group of cells in which the MB control information is valid. 
     Although  FIG.  13    shows example blocks of the process  1300 , in some aspects, the process  1300  may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in  FIG.  13   . Additionally or alternatively, two or more of the blocks of the process  1300  may be performed in parallel. 
       FIG.  14    is a flowchart illustrating an example process  1400  performed, for example, by a base station in accordance with various aspects of the present disclosure. The example process  1400  is an example where the base station (for example, base station  110 ) performs operations associated with monitoring MB control information. 
     As shown in  FIG.  14   , in some aspects, the process  1400  may include transmitting a notification of a change to MB control information, the MB control information being included in one of: an MB control channel communication scheduled by a PDCCH communication addressed to an MB radio network temporary identifier, a system information block scheduled by a PDCCH communication addressed to a system information radio network temporary identifier, or a unicast radio resource control message scheduled by a PDCCH communication addressed to a cell radio network temporary identifier (block  1410 ). For example, the base station (for example, using transmit processor  220 , controller/processor  240 , or memory  242 , among other examples) may transmit a notification of a change to MB control information, as described above. In some aspects, the MB control information is included in one of: an MB control channel communication scheduled by a PDCCH communication addressed to an MB radio network temporary identifier, a system information block scheduled by a PDCCH communication addressed to a system information radio network temporary identifier, or a unicast radio resource control message scheduled by a PDCCH communication addressed to a cell radio network temporary identifier. 
     As further shown in  FIG.  14   , in some aspects, the process  1400  may include transmitting updated MB control information based at least in part on transmitting the notification of the change to the MB control information (block  1420 ). For example, the base station (for example, using transmit processor  220 , controller/processor  240 , or memory  242 , among other examples) may transmit updated MB control information based at least in part on transmitting the notification of the change to the MB control information, as described above. 
     The process  1400  may include additional aspects, such as any single aspect or any combination of aspects described in connection with one or more other processes described elsewhere herein. 
     Although  FIG.  14    shows example blocks of the process  1400 , in some aspects, the process  1400  may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in  FIG.  14   . Additionally or alternatively, two or more of the blocks of the process  1400  may be performed in parallel. 
       FIG.  15    is a block diagram of an example apparatus  1500  for wireless communication in accordance with various aspects of the present disclosure. The apparatus  1500  may be a UE, or a UE may include the apparatus  1500 . In some aspects, the apparatus  1500  includes a reception component  1502 , a communication manager  1504 , and a transmission component  1506 , which may be in communication with one another (for example, via one or more buses). As shown, the apparatus  1500  may communicate with another apparatus  1508  (such as a UE, a base station, or another wireless communication device) using the reception component  1502  and the transmission component  1506 . 
     In some aspects, the apparatus  1500  may be configured to perform one or more operations described herein in connection with  FIGS.  4 - 10   . Additionally or alternatively, the apparatus  1500  may be configured to perform one or more processes described herein, such as process  1100  of  FIG.  11   , process  1200  of  FIG.  12   , process  1300  of  FIG.  13   , or a combination thereof. In some aspects, the apparatus  1500  may include one or more components of the UE described above in connection with  FIG.  2   . 
     The reception component  1502  may receive communications, such as reference signals, control information, data communications, or a combination thereof, from the apparatus  1508 . The reception component  1502  may provide received communications to one or more other components of the apparatus  1500 , such as the communication manager  1504 . In some aspects, the reception component  1502  may perform signal processing on the received communications (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, de-mapping, equalization, interference cancellation, or decoding, among other examples), and may provide the processed signals to the one or more other components. In some aspects, the reception component  1502  may include one or more antennas, a demodulator, a MIMO detector, a receive processor, a controller/processor, a memory, or a combination thereof, of the UE described above in connection with  FIG.  2   . 
     The transmission component  1506  may transmit communications, such as reference signals, control information, data communications, or a combination thereof, to the apparatus  1508 . In some aspects, the communication manager  1504  may generate communications and may transmit the generated communications to the transmission component  1506  for transmission to the apparatus  1508 . In some aspects, the transmission component  1506  may perform signal processing on the generated communications (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or encoding, among other examples), and may transmit the processed signals to the apparatus  1508 . In some aspects, the transmission component  1506  may include one or more antennas, a modulator, a transmit MIMO processor, a transmit processor, a controller/processor, a memory, or a combination thereof, of the UE described above in connection with  FIG.  2   . In some aspects, the transmission component  1506  may be co-located with the reception component  1502  in a transceiver. 
     The communication manager  1504  may receive or may cause the reception component  1502  to receive a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in an MBCCH scheduled by a PDCCH communication addressed to an MB-RNTI. The communication manager  1504  may monitor one or more resources of the MBCCH to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. In some aspects, the communication manager  1504  may perform one or more operations described elsewhere herein as being performed by one or more components of the communication manager  1504 . 
     The communication manager  1504  may include a controller/processor, a memory, or a combination thereof, of the UE described above in connection with  FIG.  2   . In some aspects, the communication manager  1504  includes a set of components, such as a monitoring component  1510 . Alternatively, the set of components may be separate and distinct from the communication manager  1504 . In some aspects, one or more components of the set of components may include or may be implemented within a controller/processor, a memory, or a combination thereof, of the UE described above in connection with  FIG.  2   . Additionally or alternatively, one or more components of the set of components may be implemented at least in part as software stored in a memory. For example, a component (or a portion of a component) may be implemented as instructions or code stored in a non-transitory computer-readable medium and executable by a controller or a processor to perform the functions or operations of the component. 
     The reception component  1502  may receive a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in an MBCCH scheduled by a PDCCH communication addressed to an MB-RNTI. The reception component  1502  and/or the monitoring component  1510  may monitor one or more resources of the MBCCH to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     The reception component  1502  may receive an MB control information change notification associated with an MB service to which the UE is not subscribed. The reception component  1502  and/or the monitoring component  1510  may refrain from monitoring for updated MB control information based at least in part on receiving the MB control information change notification associated with the MB service to which the UE is not subscribed. 
     The reception component  1502  may receive an MB control information change notification associated with an MBCCH that is associated with a set of MB services to which the UE is not subscribed. The reception component  1502  and/or the monitoring component  1510  may refrain from monitoring for updated MB control information based at least in part on receiving the MB control information change notification associated with the MBCCH that is associated with a set of MB services to which the UE is not subscribed. 
     The reception component  1502  may receive a configuration message that indicates respective sets of MB services corresponding to each of the multiple MBCCHs. The reception component  1502  and/or the monitoring component  1510  may monitor the MBCCH based at least in part on the configuration message. 
     The reception component  1502  may receive an indication of a new MB service. The reception component  1502  and/or the monitoring component  1510  may monitor the one or more resources of the MBCCH to receive the updated MB control information based at least in part on receiving the indication of the new MB service. 
     The reception component  1502  may receive an indication of one or more resources that carry the notification of the change to the MB control information. The reception component  1502  and/or the monitoring component  1510  may monitor the one or more resources that carry the notification of the change to the MB control information. 
     The number and arrangement of components shown in  FIG.  15    are provided as an example. In practice, there may be additional components, fewer components, different components, or differently arranged components than those shown in  FIG.  15   . Furthermore, two or more components shown in  FIG.  15    may be implemented within a single component, or a single component shown in  FIG.  15    may be implemented as multiple, distributed components. Additionally or alternatively, a set of (one or more) components shown in  FIG.  15    may perform one or more functions described as being performed by another set of components shown in  FIG.  15   . 
       FIG.  16    is a block diagram of an example apparatus  1600  for wireless communication in accordance with various aspects of the present disclosure. The apparatus  1600  may be a UE, or a UE may include the apparatus  1600 . In some aspects, the apparatus  1600  includes a reception component  1602 , a communication manager  1604 , and a transmission component  1606 , which may be in communication with one another (for example, via one or more buses). As shown, the apparatus  1600  may communicate with another apparatus  1608  (such as a UE, a base station, or another wireless communication device) using the reception component  1602  and the transmission component  1606 . 
     In some aspects, the apparatus  1600  may be configured to perform one or more operations described herein in connection with  FIGS.  4 - 10   . Additionally or alternatively, the apparatus  1600  may be configured to perform one or more processes described herein, such as process  1100  of  FIG.  11   , process  1200  of  FIG.  12   , process  1300  of  FIG.  13   , or a combination thereof. In some aspects, the apparatus  1600  may include one or more components of the UE described above in connection with  FIG.  2   . 
     The reception component  1602  may receive communications, such as reference signals, control information, data communications, or a combination thereof, from the apparatus  1608 . The reception component  1602  may provide received communications to one or more other components of the apparatus  1600 , such as the communication manager  1604 . In some aspects, the reception component  1602  may perform signal processing on the received communications (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, de-mapping, equalization, interference cancellation, or decoding, among other examples), and may provide the processed signals to the one or more other components. In some aspects, the reception component  1602  may include one or more antennas, a demodulator, a MIMO detector, a receive processor, a controller/processor, a memory, or a combination thereof, of the UE described above in connection with  FIG.  2   . 
     The transmission component  1606  may transmit communications, such as reference signals, control information, data communications, or a combination thereof, to the apparatus  1608 . In some aspects, the communication manager  1604  may generate communications and may transmit the generated communications to the transmission component  1606  for transmission to the apparatus  1608 . In some aspects, the transmission component  1606  may perform signal processing on the generated communications (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or encoding, among other examples), and may transmit the processed signals to the apparatus  1608 . In some aspects, the transmission component  1606  may include one or more antennas, a modulator, a transmit MIMO processor, a transmit processor, a controller/processor, a memory, or a combination thereof, of the UE described above in connection with  FIG.  2   . In some aspects, the transmission component  1606  may be co-located with the reception component  1602  in a transceiver. 
     The communication manager  1604  may receive or may cause the reception component  1602  to receive a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in a SIB scheduled by a PDCCH communication addressed to an SI-RNTI. The communication manager  1604  may monitor the SIB to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. In some aspects, the communication manager  1604  may perform one or more operations described elsewhere herein as being performed by one or more components of the communication manager  1604 . 
     The communication manager  1604  may include a controller/processor, a memory, or a combination thereof, of the UE described above in connection with  FIG.  2   . In some aspects, the communication manager  1604  includes a set of components, such as a monitoring component  1610 . Alternatively, the set of components may be separate and distinct from the communication manager  1604 . In some aspects, one or more components of the set of components may include or may be implemented within a controller/processor, a memory, or a combination thereof, of the UE described above in connection with  FIG.  2   . Additionally or alternatively, one or more components of the set of components may be implemented at least in part as software stored in a memory. For example, a component (or a portion of a component) may be implemented as instructions or code stored in a non-transitory computer-readable medium and executable by a controller or a processor to perform the functions or operations of the component. 
     The reception component  1602  may receive a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in a SIB scheduled by a PDCCH communication addressed to an SI-RNTI. The reception component  1602  and/or the monitoring component  1610  may monitor the SIB to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     The reception component  1602  and/or the monitoring component  1610  may monitor the SIB to receive the updated MB control information based at least in part on a value of a bit, in the PDCCH communication addressed to the P-RNTI, that indicates whether there is a modification to the SIB. 
     The number and arrangement of components shown in  FIG.  16    are provided as an example. In practice, there may be additional components, fewer components, different components, or differently arranged components than those shown in  FIG.  16   . Furthermore, two or more components shown in  FIG.  16    may be implemented within a single component, or a single component shown in  FIG.  16    may be implemented as multiple, distributed components. Additionally or alternatively, a set of (one or more) components shown in  FIG.  16    may perform one or more functions described as being performed by another set of components shown in  FIG.  16   . 
       FIG.  17    is a block diagram of an example apparatus  1700  for wireless communication in accordance with various aspects of the present disclosure. The apparatus  1700  may be a UE, or a UE may include the apparatus  1700 . In some aspects, the apparatus  1700  includes a reception component  1702 , a communication manager  1704 , and a transmission component  1706 , which may be in communication with one another (for example, via one or more buses). As shown, the apparatus  1700  may communicate with another apparatus  1708  (such as a UE, a base station, or another wireless communication device) using the reception component  1702  and the transmission component  1706 . 
     In some aspects, the apparatus  1700  may be configured to perform one or more operations described herein in connection with  FIGS.  4 - 10   . Additionally or alternatively, the apparatus  1700  may be configured to perform one or more processes described herein, such as process  1100  of  FIG.  11   , process  1200  of  FIG.  12   , process  1300  of  FIG.  13   , or a combination thereof. In some aspects, the apparatus  1700  may include one or more components of the UE described above in connection with  FIG.  2   . 
     The reception component  1702  may receive communications, such as reference signals, control information, data communications, or a combination thereof, from the apparatus  1708 . The reception component  1702  may provide received communications to one or more other components of the apparatus  1700 , such as the communication manager  1704 . In some aspects, the reception component  1702  may perform signal processing on the received communications (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, de-mapping, equalization, interference cancellation, or decoding, among other examples), and may provide the processed signals to the one or more other components. In some aspects, the reception component  1702  may include one or more antennas, a demodulator, a MIMO detector, a receive processor, a controller/processor, a memory, or a combination thereof, of the UE described above in connection with  FIG.  2   . 
     The transmission component  1706  may transmit communications, such as reference signals, control information, data communications, or a combination thereof, to the apparatus  1708 . In some aspects, the communication manager  1704  may generate communications and may transmit the generated communications to the transmission component  1706  for transmission to the apparatus  1708 . In some aspects, the transmission component  1706  may perform signal processing on the generated communications (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or encoding, among other examples), and may transmit the processed signals to the apparatus  1708 . In some aspects, the transmission component  1706  may include one or more antennas, a modulator, a transmit MIMO processor, a transmit processor, a controller/processor, a memory, or a combination thereof, of the UE described above in connection with  FIG.  2   . In some aspects, the transmission component  1706  may be co-located with the reception component  1702  in a transceiver. 
     The communication manager  1704  may receive or may cause the reception component  1702  to receive a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in a unicast RRC message scheduled by a PDCCH communication addressed to a C-RNTI. The communication manager  1704  may monitor the unicast RRC message to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. In some aspects, the communication manager  1704  may perform one or more operations described elsewhere herein as being performed by one or more components of the communication manager  1704 . 
     The communication manager  1704  may include a controller/processor, a memory, or a combination thereof, of the UE described above in connection with  FIG.  2   . In some aspects, the communication manager  1704  includes a set of components, such as a monitoring component  1710 . Alternatively, the set of components may be separate and distinct from the communication manager  1704 . In some aspects, one or more components of the set of components may include or may be implemented within a controller/processor, a memory, or a combination thereof, of the UE described above in connection with  FIG.  2   . Additionally or alternatively, one or more components of the set of components may be implemented at least in part as software stored in a memory. For example, a component (or a portion of a component) may be implemented as instructions or code stored in a non-transitory computer-readable medium and executable by a controller or a processor to perform the functions or operations of the component. 
     The reception component  1702  may receive a notification of a change to MB control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in a unicast RRC message scheduled by a PDCCH communication addressed to a C-RNTI. The reception component  1702  and/or the monitoring component  1710  may monitor the unicast RRC message to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     The number and arrangement of components shown in  FIG.  17    are provided as an example. In practice, there may be additional components, fewer components, different components, or differently arranged components than those shown in  FIG.  17   . Furthermore, two or more components shown in  FIG.  17    may be implemented within a single component, or a single component shown in  FIG.  17    may be implemented as multiple, distributed components. Additionally or alternatively, a set of (one or more) components shown in  FIG.  17    may perform one or more functions described as being performed by another set of components shown in  FIG.  17   . 
       FIG.  18    is a block diagram of an example apparatus  1800  for wireless communication in accordance with various aspects of the present disclosure. The apparatus  1800  may be a base station, or a base station may include the apparatus  1800 . In some aspects, the apparatus  1800  includes a reception component  1802 , a communication manager  1804 , and a transmission component  1806 , which may be in communication with one another (for example, via one or more buses). As shown, the apparatus  1800  may communicate with another apparatus  1808  (such as a UE, a base station, or another wireless communication device) using the reception component  1802  and the transmission component  1806 . 
     In some aspects, the apparatus  1800  may be configured to perform one or more operations described herein in connection with  FIGS.  4 - 10   . Additionally or alternatively, the apparatus  1800  may be configured to perform one or more processes described herein, such as process  1400  of  FIG.  14   . In some aspects, the apparatus  1800  may include one or more components of the base station described above in connection with  FIG.  2   . 
     The reception component  1802  may receive communications, such as reference signals, control information, data communications, or a combination thereof, from the apparatus  1808 . The reception component  1802  may provide received communications to one or more other components of the apparatus  1800 , such as the communication manager  1804 . In some aspects, the reception component  1802  may perform signal processing on the received communications (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, de-mapping, equalization, interference cancellation, or decoding, among other examples), and may provide the processed signals to the one or more other components. In some aspects, the reception component  1802  may include one or more antennas, a demodulator, a MIMO detector, a receive processor, a controller/processor, a memory, or a combination thereof, of the base station described above in connection with  FIG.  2   . 
     The transmission component  1806  may transmit communications, such as reference signals, control information, data communications, or a combination thereof, to the apparatus  1808 . In some aspects, the communication manager  1804  may generate communications and may transmit the generated communications to the transmission component  1806  for transmission to the apparatus  1808 . In some aspects, the transmission component  1806  may perform signal processing on the generated communications (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or encoding, among other examples), and may transmit the processed signals to the apparatus  1808 . In some aspects, the transmission component  1806  may include one or more antennas, a modulator, a transmit MIMO processor, a transmit processor, a controller/processor, a memory, or a combination thereof, of the base station described above in connection with  FIG.  2   . In some aspects, the transmission component  1806  may be co-located with the reception component  1802  in a transceiver. 
     The communication manager  1804  may transmit or may cause the transmission component  1806  to transmit a notification of a change to MB control information, the MB control information being included in one of an MB control channel communication scheduled by a PDCCH communication addressed to an MB radio network temporary identifier, a system information block scheduled by a PDCCH communication addressed to a system information radio network temporary identifier, or a unicast radio resource control message scheduled by a PDCCH communication addressed to a cell radio network temporary identifier. The communication manager  1804  may transmit or may cause the transmission component  1806  to transmit updated MB control information based at least in part on transmitting the notification of the change to the MB control information. In some aspects, the communication manager  1804  may perform one or more operations described elsewhere herein as being performed by one or more components of the communication manager  1804 . 
     The communication manager  1804  may include a controller/processor, a memory, a scheduler, a communication unit, or a combination thereof, of the base station described above in connection with  FIG.  2   . In some aspects, the communication manager  1804  includes a set of components. Alternatively, the set of components may be separate and distinct from the communication manager  1804 . In some aspects, one or more components of the set of components may include or may be implemented within a controller/processor, a memory, a scheduler, a communication unit, or a combination thereof, of the base station described above in connection with  FIG.  2   . Additionally or alternatively, one or more components of the set of components may be implemented at least in part as software stored in a memory. For example, a component (or a portion of a component) may be implemented as instructions or code stored in a non-transitory computer-readable medium and executable by a controller or a processor to perform the functions or operations of the component. 
     The transmission component  1806  may transmit a notification of a change to MB control information, the MB control information being included in one of an MB control channel communication scheduled by a PDCCH communication addressed to an MB radio network temporary identifier, a system information block scheduled by a PDCCH communication addressed to a system information radio network temporary identifier, or a unicast radio resource control message scheduled by a PDCCH communication addressed to a cell radio network temporary identifier. The transmission component  1806  may transmit updated MB control information based at least in part on transmitting the notification of the change to the MB control information. 
     The number and arrangement of components shown in  FIG.  18    are provided as an example. In practice, there may be additional components, fewer components, different components, or differently arranged components than those shown in  FIG.  18   . Furthermore, two or more components shown in  FIG.  18    may be implemented within a single component, or a single component shown in  FIG.  18    may be implemented as multiple, distributed components. Additionally or alternatively, a set of (one or more) components shown in  FIG.  18    may perform one or more functions described as being performed by another set of components shown in  FIG.  18   . 
     The following provides an overview of aspects of the present disclosure: 
     Aspect 1: A method of wireless communication performed by a user equipment (UE), comprising: receiving a notification of a change to multicast broadcast (MB) control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in an MB control channel (MBCCH) scheduled by a physical downlink control channel (PDCCH) communication addressed to an MB radio network temporary identifier (MB-RNTI); and monitoring one or more resources of the MBCCH to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     Aspect 2: The method of aspect 1, wherein the MBCCH is a single MBCCH used to transmit MB control information for all MB services associated with a service area of the UE. 
     Aspect 3: The method of aspect 2, wherein the notification is triggered based at least in part on a change to any MB service associated with a service area of the UE. 
     Aspect 4: The method of aspect 2, wherein the single MBCCH is associated with multiple sets of MB services and a separate MB control information change notification is associated with each of the multiple sets of MB services. 
     Aspect 5: The method of aspect 4, further comprising: receiving an MB control information change notification associated with an MB service to which the UE is not subscribed; and refraining from monitoring for updated MB control information based at least in part on receiving the MB control information change notification associated with the MB service to which the UE is not subscribed. 
     Aspect 6: The method of aspect 1, wherein the MBCCH is one of multiple MBCCHs, each of the multiple MBCCHs being associated with a different set of MB services. 
     Aspect 7: The method of aspect 6, wherein a separate MB control information change is associated with each of the multiple MBCCHs. 
     Aspect 8: The method of aspect 7, further comprising: receiving an MB control information change notification associated with an MBCCH that is associated with a set of MB services to which the UE is not subscribed; and refraining from monitoring for updated MB control information based at least in part on receiving the MB control information change notification associated with the MBCCH that is associated with a set of MB services to which the UE is not subscribed. 
     Aspect 9: The method of aspect 6, wherein at least two MBCCHs of the multiple MBCCHs are associated with a same MB-RNTI. 
     Aspect 10: The method of aspect 9, wherein different MBCCHs, of the at least two MBCCHs that are associated with the same MB-RNTI, are associated with different non-overlapping scheduling windows, different hybrid automatic repeat request processes, different logical channel identifiers, or a combination thereof. 
     Aspect 11: The method of aspect 6, wherein at least two MBCCHs of the multiple MBCCHs are associated with different MB-RNTIs. 
     Aspect 12: The method of aspect 6, wherein at least two MBCCHs of the multiple MBCCHs correspond to different bandwidth part configurations. 
     Aspect 13: The method of aspect 6, further comprising: receiving a configuration message that indicates respective sets of MB services corresponding to each of the multiple MBCCHs; and monitoring the MBCCH based at least in part on the configuration message. 
     Aspect 14: The method of any of the preceding aspects, further comprising: receiving an indication of a new MB service; and monitoring the one or more resources of the MBCCH to receive the updated MB control information based at least in part on receiving the indication of the new MB service. 
     Aspect 15: The method of any of the preceding aspects, wherein the notification of the change to the MB control information is included in the PDCCH communication addressed to the MB-RNTI. 
     Aspect 16: The method of aspect 15, wherein the PDCCH communication addressed to the MB-RNTI includes an indication of whether the PDCCH communication includes scheduling information for the MBCCH and not the notification of the change, includes the notification of the change and not the scheduling information, or includes both the scheduling information and the notification of the change. 
     Aspect 17: The method of any one of aspects 15-16, wherein the notification of the change includes a bitmap, and wherein different bits of the bitmap correspond to different MBCCHs associated with different sets of MB services or to different sets of MB services in a single MBCCH. 
     Aspect 18: The method of aspect 17, wherein the bitmap includes a bit to indicate a new MB service. 
     Aspect 19: The method of any one of the preceding aspects, further comprising: receiving an indication of one or more resources that carry the notification of the change to the MB control information; and monitoring the one or more resources that carry the notification of the change to the MB control information. 
     Aspect 20: The method of any one of the preceding aspects, wherein the notification of the change to the MB control information is received by the UE in a message addressed to a different RNTI than the MB-RNTI to which the PDCCH communication is addressed. 
     Aspect 21: A method of wireless communication performed by a user equipment (UE), comprising: receiving a notification of a change to multicast broadcast (MB) control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in a system information block (SIB) scheduled by a physical downlink control channel (PDCCH) communication addressed to a system information radio network temporary identifier (SI-RNTI); and monitoring the SIB to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     Aspect 22: The method of aspect 21, wherein the notification of the change to the MB control information is included in a PDCCH communication addressed to a paging RNTI (P-RNTI). 
     Aspect 23: The method of aspect 22, wherein the PDCCH communication addressed to the P-RNTI includes at least one of an indication of whether there is a modification to system information other than a set of SIBs that includes the SIB carrying the MB control information, an indication of whether there is a modification to the SIB carrying the MB control information, or a combination thereof. 
     Aspect 24: The method of any one of aspects 22-23, further comprising monitoring the SIB to receive the updated MB control information based at least in part on a value of a bit, in the PDCCH communication addressed to the P-RNTI, that indicates whether there is a modification to the SIB. 
     Aspect 25: The method of any one of aspects 22-24, wherein the PDCCH communication addressed to the P-RNTI includes at least one of an indication of whether there is a modification to a specific set of MB services, an indication of a new MB service, or a combination thereof. 
     Aspect 26: The method of any one of aspects 22-25, wherein the PDCCH communication addressed to the P-RNTI includes an indication of whether there is a modification to the SIB, and wherein a paging message corresponding to the PDCCH communication indicates a specific set of MB services associated with the notification of the change to the MB control information. 
     Aspect 27: The method of any one of aspects 21-26, wherein the notification of the change to the MB control information is included in a PDCCH communication addressed to an RNTI other than a paging RNTI and the SI-RNTI. 
     Aspect 28: The method of aspect 27, wherein the PDCCH communication addressed to the RNTI other than the paging RNTI and the SI-RNTI includes at least one of: multiple bits, wherein different bits indicate a change to MB control information for different sets of MB services, an indication of a new MB service, or a combination thereof. 
     Aspect 29: The method of aspect 27, wherein a PDCCH communication addressed to a paging RNTI includes an indication of whether there is a modification to system information other than a set of SIBs that includes the SIB that carries the MB control information. 
     Aspect 30: A method of wireless communication performed by a user equipment (UE), comprising: receiving a notification of a change to multicast broadcast (MB) control information associated with at least one MB service to which the UE is subscribed, the MB control information being included in a unicast radio resource control (RRC) message scheduled by a physical downlink control channel (PDCCH) communication addressed to a cell radio network temporary identifier (C-RNTI); and monitoring the unicast RRC message to receive updated MB control information based at least in part on receiving the notification of the change to the MB control information. 
     Aspect 31: The method of aspect 30, wherein the notification of the change is indicated in at least one of: dedicated RRC signaling, a paging message, a short message indication, or a combination thereof. 
     Aspect 32: The method of any one of aspects 30-31, wherein the MB control information includes an indication of a group of cells in which the MB control information is valid. 
     Aspect 33: A method of wireless communication performed by a base station, comprising: transmitting a notification of a change to multicast broadcast (MB) control information, the MB control information being included in one of: an MB control channel communication scheduled by a physical downlink control channel (PDCCH) communication addressed to an MB radio network temporary identifier, a system information block scheduled by a PDCCH communication addressed to a system information radio network temporary identifier, or a unicast radio resource control message scheduled by a PDCCH communication addressed to a cell radio network temporary identifier; and transmitting updated MB control information based at least in part on transmitting the notification of the change to the MB control information. 
     Aspect 34: An apparatus for wireless communication at a device, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method of one or more aspects of aspects 1-20. 
     Aspect 35: A device for wireless communication, comprising a memory and one or more processors coupled to the memory, the memory and the one or more processors configured to perform the method of one or more aspects of aspects 1-20. 
     Aspect 36: An apparatus for wireless communication, comprising at least one means for performing the method of one or more aspects of aspects 1-20. 
     Aspect 37: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method of one or more aspects of aspects 1-20. 
     Aspect 38: A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform the method of one or more aspects of aspects 1-20. 
     Aspect 39: An apparatus for wireless communication at a device, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method of one or more aspects of aspects 21-29. 
     Aspect 40: A device for wireless communication, comprising a memory and one or more processors coupled to the memory, the memory and the one or more processors configured to perform the method of one or more aspects of aspects 21-29. 
     Aspect 41: An apparatus for wireless communication, comprising at least one means for performing the method of one or more aspects of aspects 21-29. 
     Aspect 42: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method of one or more aspects of aspects 21-29. 
     Aspect 43: A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform the method of one or more aspects of aspects 21-29. 
     Aspect 44: An apparatus for wireless communication at a device, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method of one or more aspects of aspects 30-32. 
     Aspect 45: A device for wireless communication, comprising a memory and one or more processors coupled to the memory, the memory and the one or more processors configured to perform the method of one or more aspects of aspects 30-32. 
     Aspect 46: An apparatus for wireless communication, comprising at least one means for performing the method of one or more aspects of aspects 30-32. 
     Aspect 47: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method of one or more aspects of aspects 30-32. 
     Aspect 48: A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform the method of one or more aspects of aspects 30-32. 
     Aspect 49: An apparatus for wireless communication at a device, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method of aspect 33. 
     Aspect 50: A device for wireless communication, comprising a memory and one or more processors coupled to the memory, the memory and the one or more processors configured to perform the method of aspect 33. 
     Aspect 51: An apparatus for wireless communication, comprising at least one means for performing the method of aspect 33. 
     Aspect 52: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method of aspect 33. 
     Aspect 53: A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform the method of aspect 33. 
     The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the precise form disclosed. Modifications and variations may be made in light of the above disclosure or may be acquired from practice of the aspects. 
     As used herein, the term “component” is intended to be broadly construed as hardware, firmware, or a combination of hardware and software. As used herein, a processor is implemented in hardware, firmware, or a combination of hardware and software. 
     Some aspects are described herein in connection with thresholds. As used herein, satisfying a threshold may, depending on the context, refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, or not equal to the threshold, among other examples, or combinations thereof. 
     It will be apparent that systems or methods described herein may be implemented in different forms of hardware, firmware, or a combination of hardware and software. The actual specialized control hardware or software code used to implement these systems or methods is not limiting of the aspects. Thus, the operation and behavior of the systems or methods were described herein without reference to specific software code—it being understood that software and hardware can be designed to implement the systems or methods based, at least in part, on the description herein. 
     Even though particular combinations of features are recited in the claims or disclosed in the specification, these combinations are not intended to limit the disclosure of various aspects. In fact, many of these features may be combined in ways not specifically recited in the claims or disclosed in the specification. Although each dependent claim listed below may directly depend on only one claim, the disclosure of various aspects includes each dependent claim in combination with every other claim in the claim set. 
     As used herein, “or” is used intended to be interpreted in the inclusive sense, unless otherwise explicitly indicated. For example, “a or b” may include a only, b only, or a combination of a and b. As used herein, a phrase referring to “at least one of” or “one or more of” a list of items refers to any combination of those items, including single members. For example, “at least one of: a, b, or c” is intended to cover the possibilities of: a only, b only, c only, a combination of a and b, a combination of a and c, a combination of b and c, and a combination of a and b and c. 
     No element, act, or instruction used herein is to be construed as critical or essential unless explicitly described as such. Also, as used herein, the articles “a” and “an” are intended to include one or more items, and may be used interchangeably with “one or more.” Furthermore, as used herein, the terms “set” and “group” are intended to include one or more items (for example, related items, unrelated items, or a combination of related and unrelated items), and may be used interchangeably with “one or more.” Where only one item is intended, the phrase “only one” or similar language is used. Also, as used herein, the terms “has,” “have,” or “having,” or similar terms are intended to be open-ended terms. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise.