Patent Publication Number: US-2022224475-A1

Title: Demodulation reference signal bundling for physical uplink control channel repetitions

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This patent application claims priority to U.S. Provisional Patent Application No. 63/137,193, filed on Jan. 14, 2021, entitled “DMRS BUNDLING FOR PUCCH REPETITIONS,” and assigned to the assignee hereof. The disclosure of the prior application is considered part of and is incorporated by reference into this patent application. 
    
    
     FIELD OF THE DISCLOSURE 
     Aspects of the present disclosure generally relate to wireless communication and to techniques and apparatuses for demodulation reference signal (DMRS) bundling for physical uplink control channel (PUCCH) repetitions. 
     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 (e.g., bandwidth, transmit power, or the like). 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). 
     A wireless network may include a number of base stations (BSs) that can support communication for a number of user equipment (UEs). A UE may communicate with a BS via the downlink and uplink. “Downlink” (or “forward link”) refers to the communication link from the BS to the UE, and “uplink” (or “reverse link”) refers to the communication link from the UE to the BS. As will be described in more detail herein, a BS may be referred to as a Node B, a gNB, an access point (AP), a radio head, a transmit receive point (TRP), a New Radio (NR) BS, a 5G Node B, or the like. 
     The above multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different user equipment to communicate on a municipal, national, regional, and even global level. 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 and/or SC-FDM (e.g., 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. As the demand for mobile broadband access continues to increase, further improvements in LTE, NR, and other radio access technologies remain useful. 
     SUMMARY 
     In some aspects, a method of wireless communication performed by a user equipment (UE) includes receiving, from a base station, an indication that demodulation reference signal (DMRS) bundling is to be used for channel estimation by the base station for one or more physical uplink control channel (PUCCH) repetitions, where the indication is a semi-static configuration or a dynamic indication; and transmitting, to the base station, the one or more PUCCH repetitions by maintaining a phase continuity among DMRSs of the one or more PUCCH repetitions based at least in part on receiving the indication that DMRS bundling is to be used. 
     In some aspects, a method of wireless communication performed by a base station includes transmitting, to one or more UEs, an indication that DMRS bundling is to be used for channel estimation by the base station for PUCCH repetitions, where the indication is a semi-static configuration or a dynamic indication; receiving, from a UE of the one or more UEs, one or more PUCCH repetitions; and performing a channel estimation of an uplink channel associated with the one or more PUCCH repetitions by applying DMRS bundling among DMRSs of the one or more PUCCH repetitions. 
     In some aspects, a UE for wireless communication includes a memory and one or more processors, coupled to the memory, configured to: receive, from a base station, an indication that DMRS bundling is to be used for channel estimation by the base station for one or more PUCCH repetitions, where the indication is a semi-static configuration or a dynamic indication; and transmit, to the base station, the one or more PUCCH repetitions by maintaining a phase continuity among DMRSs of the one or more PUCCH repetitions based at least in part on receiving the indication that DMRS bundling is to be used. 
     In some aspects, a base station for wireless communication includes a memory and one or more processors, coupled to the memory, configured to: transmit, to one or more UEs, an indication that DMRS bundling is to be used for channel estimation by the base station for PUCCH repetitions, where the indication is a semi-static configuration or a dynamic indication; receive, from a UE of the one or more UEs, one or more PUCCH repetitions; and perform a channel estimation of an uplink channel associated with the one or more PUCCH repetitions by applying DMRS bundling among DMRSs of the one or more PUCCH repetitions. 
     In some aspects, a non-transitory computer-readable medium storing a set of instructions for wireless communication includes one or more instructions that, when executed by one or more processors of a UE, cause the UE to: receive, from a base station, an indication that DMRS bundling is to be used for channel estimation by the base station for one or more PUCCH repetitions, where the indication is a semi-static configuration or a dynamic indication; and transmit, to the base station, the one or more PUCCH repetitions by maintaining a phase continuity among DMRSs of the one or more PUCCH repetitions based at least in part on receiving the indication that DMRS bundling is to be used. 
     In some aspects, a non-transitory computer-readable medium storing a set of instructions for wireless communication includes one or more instructions that, when executed by one or more processors of a base station, cause the base station to: transmit, to one or more UEs, an indication that DMRS bundling is to be used for channel estimation by the base station for PUCCH repetitions, where the indication is a semi-static configuration or a dynamic indication; receive, from a UE of the one or more UEs, one or more PUCCH repetitions; and perform a channel estimation of an uplink channel associated with the one or more PUCCH repetitions by applying DMRS bundling among DMRSs of the one or more PUCCH repetitions. 
     In some aspects, an apparatus for wireless communication includes means for receiving, from a base station, an indication that DMRS bundling is to be used for channel estimation by the base station for one or more PUCCH repetitions, where the indication is a semi-static configuration or a dynamic indication; and means for transmitting, to the base station, the one or more PUCCH repetitions by maintaining a phase continuity among DMRSs of the one or more PUCCH repetitions based at least in part on receiving the indication that DMRS bundling is to be used. 
     In some aspects, an apparatus for wireless communication includes means for transmitting, to one or more UEs, an indication that DMRS bundling is to be used for channel estimation by the apparatus for PUCCH repetitions, where the indication is a semi-static configuration or a dynamic indication; means for receiving, from a UE of the one or more UEs, one or more PUCCH repetitions; and means for performing a channel estimation of an uplink channel associated with the one or more PUCCH repetitions by applying DMRS bundling among DMRSs of the one or more PUCCH repetitions. 
     Aspects generally include a method, apparatus, system, computer program product, non-transitory computer-readable medium, user equipment, base station, wireless communication device, and/or processing system as substantially described herein with reference to and as illustrated by the drawings and specification. 
     The foregoing has outlined rather broadly the features and technical advantages of examples according to 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. 
     While aspects are described in the present disclosure by illustration to some examples, those skilled in the art will understand that such aspects may be implemented in many different arrangements and scenarios. Techniques described herein may be implemented using different platform types, devices, systems, shapes, sizes, and/or packaging arrangements. For example, some aspects may be implemented via integrated chip embodiments or other non-module-component based devices (e.g., end-user devices, vehicles, communication devices, computing devices, industrial equipment, retail/purchasing devices, medical devices, or artificial intelligence-enabled devices). Aspects may be implemented in chip-level components, modular components, non-modular components, non-chip-level components, device-level components, or system-level components. Devices incorporating described aspects and features may include additional components and features for implementation and practice of claimed and described aspects. For example, transmission and reception of wireless signals may include a number of components for analog and digital purposes (e.g., hardware components including antennas, radio frequency (RF) chains, power amplifiers, modulators, buffers, processor(s), interleavers, adders, or summers). It is intended that aspects described herein may be practiced in a wide variety of devices, components, systems, distributed arrangements, or end-user devices of varying size, shape, and constitution. 
    
    
     
       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 certain 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 diagram illustrating an example of a wireless network, in accordance with the present disclosure. 
         FIG. 2  is a diagram illustrating an example of a base station in communication with a user equipment (UE) in a wireless network, in accordance with the present disclosure. 
         FIG. 3  is a diagram illustrating an example of a frame structure in a wireless communication network, in accordance with the present disclosure. 
         FIGS. 4-6  are diagrams illustrating examples associated with demodulation reference signal (DMRS) bundling for physical uplink control channel (PUCCH) repetitions, in accordance with the present disclosure. 
         FIGS. 7 and 8  are diagrams illustrating example processes associated with DMRS bundling for PUCCH repetitions, in accordance with the present disclosure. 
         FIGS. 9 and 10  are block diagrams of example apparatuses for wireless communication, in accordance with 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 should not be construed as limited to any specific structure or function presented throughout this disclosure. Rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Based on the teachings herein, one skilled in the art should 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 number 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. It should be understood that 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, algorithms, or the like (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. 
     It should be noted that while aspects may be described herein using terminology commonly associated with a 5G or NR radio access technology (RAT), aspects of the present disclosure can be applied to other RATs, such as a 3G RAT, a 4G RAT, and/or a RAT subsequent to 5G (e.g., 6G). 
       FIG. 1  is a diagram illustrating an example of a wireless network  100 , in accordance with the present disclosure. The wireless network  100  may be or may include elements of a 5G (NR) network and/or an LTE network, among other examples. The wireless network  100  may include a number of base stations  110  (shown as BS  110   a , BS  110   b , BS  110   c , and BS  110   d ) and other network entities. A base station (BS) is an entity that communicates with user equipment (UEs) and may also be referred to as an NR BS, a Node B, a gNB, a 5G node B (NB), an access point, a transmit receive point (TRP), or the like. 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 and/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, and/or another type of cell. A macro cell may cover a relatively large geographic area (e.g., 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 (e.g., a home) and may allow restricted access by UEs having association with the femto cell (e.g., UEs in a closed subscriber group (CSG)). ABS for a macro cell may be referred to as a macro BS. ABS for a pico cell may be referred to as a pico BS. A BS for a femto cell may be referred to as a femto BS or a home BS. 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 BS may support one or multiple (e.g., three) cells. The terms “eNB”, “base station”, “NR BS”, “gNB”, “TRP”, “AP”, “node B”, “5G NB”, and “cell” may be used interchangeably herein. 
     In some aspects, a cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of a mobile BS. In some aspects, the BSs may be interconnected to one another and/or to one or more other BSs or network nodes (not shown) in the wireless network  100  through various types of backhaul interfaces, such as a direct physical connection or a virtual network, using any suitable transport network. 
     Wireless network  100  may also include relay stations. A relay station is an entity that can receive a transmission of data from an upstream station (e.g., a BS or a UE) and send a transmission of the data to a downstream station (e.g., 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 BS  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 BS may also be referred to as a relay station, a relay base station, a relay, or the like. 
     Wireless network  100  may be a heterogeneous network that includes BSs of different types, such as macro BSs, pico BSs, femto BSs, relay BSs, or the like. These different types of BSs may have different transmit power levels, different coverage areas, and different impacts on interference in wireless network  100 . For example, macro BSs may have a high transmit power level (e.g., 5 to 40 watts) whereas pico BSs, femto BSs, and relay BSs may have lower transmit power levels (e.g., 0.1 to 2 watts). 
     A network controller  130  may couple to a set of BSs 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, directly or indirectly, via a wireless or wireline backhaul. 
     UEs  120  (e.g.,  120   a ,  120   b ,  120   c ) may be dispersed throughout wireless network  100 , 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, a station, or the like. A UE may be a cellular phone (e.g., a smart phone), a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet, 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 (e.g., smart ring, smart bracelet)), an entertainment device (e.g., 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 or wired 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, and/or location tags, that may communicate with a base station, another device (e.g., remote device), or some other entity. A wireless node may provide, for example, connectivity for or to a network (e.g., 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, and/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 and/or memory components. In some aspects, the processor components and the memory components may be coupled together. For example, the processor components (e.g., one or more processors) and the memory components (e.g., a memory) may be operatively coupled, communicatively coupled, electronically coupled, and/or electrically coupled. 
     In general, any number of wireless networks may be deployed in a given geographic area. Each wireless network may support a particular RAT and may operate on one or more frequencies. A RAT may also be referred to as a radio technology, an air interface, or the like. A frequency may also be referred to as a carrier, a frequency channel, or the like. 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 cases, NR or 5G RAT networks may be deployed. 
     In some aspects, two or more UEs  120  (e.g., shown as UE  120   a  and UE  120   e ) may communicate directly using one or more sidelink channels (e.g., without using a base station  110  as an intermediary to communicate with one another). For example, the UEs  120  may communicate using peer-to-peer (P2P) communications, device-to-device (D2D) communications, a vehicle-to-everything (V2X) protocol (e.g., which may include a vehicle-to-vehicle (V2V) protocol or a vehicle-to-infrastructure (V2I) protocol), and/or a mesh network. In this case, the UE  120  may perform scheduling operations, resource selection operations, and/or other operations described elsewhere herein as being performed by the base station  110 . 
     Devices of wireless network  100  may communicate using the electromagnetic spectrum, which may be subdivided based on frequency or wavelength into various classes, bands, channels, or the like. For example, devices of wireless network  100  may communicate using an operating band having a first frequency range (FR1), which may span from 410 MHz to 7.125 GHz, and/or may communicate using an operating band having a second frequency range (FR2), which may span from 24.25 GHz to 52.6 GHz. The frequencies between FR1 and FR2 are sometimes referred to as mid-band frequencies. Although a portion of FR1 is greater than 6 GHz, FR1 is often referred to as a “sub-6 GHz” band. Similarly, FR2 is often referred to as a “millimeter wave” band despite being different from the extremely high frequency (EHF) band (30 GHz-300 GHz) which is identified by the International Telecommunications Union (ITU) as a “millimeter wave” band. Thus, unless specifically stated otherwise, it should be understood that the term “sub-6 GHz” or the like, if used herein, may broadly represent frequencies less than 6 GHz, frequencies within FR1, and/or mid-band frequencies (e.g., greater than 7.125 GHz). Similarly, unless specifically stated otherwise, it should be understood that the term “millimeter wave” or the like, if used herein, may broadly represent frequencies within the EHF band, frequencies within FR2, and/or mid-band frequencies (e.g., less than 24.25 GHz). It is contemplated that the frequencies included in FR1 and FR2 may be modified, and techniques described herein are applicable to those modified frequency ranges. 
     As indicated above,  FIG. 1  is provided as an example. Other examples may differ from what is described with regard to  FIG. 1 . 
       FIG. 2  is a diagram illustrating an example  200  of a base station  110  in communication with a UE  120  in a wireless network  100 , in accordance with 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 (MCS) for each UE based at least in part on channel quality indicators (CQIs) received from the UE, process (e.g., encode and modulate) 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 (e.g., for semi-static resource partitioning information (SRPI)) and control information (e.g., CQI requests, grants, and/or upper layer signaling) and provide overhead symbols and control symbols. Transmit processor  220  may also generate reference symbols for reference signals (e.g., a cell-specific reference signal (CRS) or a demodulation reference signal (DMRS)) and synchronization signals (e.g., a primary synchronization signal (PSS) or a secondary synchronization signal (SSS)). A transmit (TX) multiple-input multiple-output (MIMO) processor  230  may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, the overhead symbols, and/or the reference symbols, if applicable, and may provide T output symbol streams to Tmodulators (MODs)  232   a  through  232   t . Each modulator  232  may process a respective output symbol stream (e.g., for OFDM) to obtain an output sample stream. Each modulator  232  may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. T downlink signals from modulators  232   a  through  232   t  may be transmitted via T antennas  234   a  through  234   t , respectively. 
     At UE  120 , antennas  252   a  through  252   r  may receive the downlink signals from base station  110  and/or other base stations and may provide received signals to demodulators (DEMODs)  254   a  through  254   r , respectively. Each demodulator  254  may condition (e.g., filter, amplify, downconvert, and digitize) a received signal to obtain input samples. Each demodulator  254  may further process the input samples (e.g., for OFDM) to obtain received symbols. A MIMO detector  256  may obtain received symbols from all R demodulators  254   a  through  254   r , perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor  258  may process (e.g., demodulate and 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 . The term “controller/processor” may refer to one or more controllers, one or more processors, or a combination thereof. A channel processor may determine a reference signal received power (RSRP) parameter, a received signal strength indicator (RSSI) parameter, a reference signal received quality (RSRQ) parameter, and/or a CQI parameter, among other examples. In some aspects, one or more components of UE  120  may be included in a housing  284 . 
     Network controller  130  may include communication unit  294 , controller/processor  290 , and memory  292 . Network controller  130  may include, for example, one or more devices in a core network. Network controller  130  may communicate with base station  110  via communication unit  294 . 
     Antennas (e.g., antennas  234   a  through  234   t  and/or antennas  252   a  through  252   r ) may include, or may be included within, one or more antenna panels, antenna groups, sets of antenna elements, and/or antenna arrays, among other examples. An antenna panel, an antenna group, a set of antenna elements, and/or an antenna array may include one or more antenna elements. An antenna panel, an antenna group, a set of antenna elements, and/or an antenna array may include a set of coplanar antenna elements and/or a set of non-coplanar antenna elements. An antenna panel, an antenna group, a set of antenna elements, and/or an antenna array may include antenna elements within a single housing and/or antenna elements within multiple housings. An antenna panel, an antenna group, a set of antenna elements, and/or an antenna array may include one or more antenna elements coupled to one or more transmission and/or reception components, such as one or more components of  FIG. 2 . 
     On the uplink, at UE  120 , a transmit processor  264  may receive and process data from a data source  262  and control information (e.g., for reports that include RSRP, RSSI, RSRQ, and/or CQI) 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 modulators  254   a  through  254   r  (e.g., for DFT-s-OFDM or CP-OFDM), and transmitted to base station  110 . In some aspects, a modulator and a demodulator (e.g., MOD/DEMOD  254 ) of the UE  120  may be included in a modem of the UE  120 . In some aspects, the UE  120  includes a transceiver. The transceiver may include any combination of antenna(s)  252 , modulators and/or demodulators  254 , MIMO detector  256 , receive processor  258 , transmit processor  264 , and/or TX MIMO processor  266 . The transceiver may be used by a processor (e.g., controller/processor  280 ) and memory  282  to perform aspects of any of the methods described herein (for example, as described with reference to  FIGS. 4-10 ). 
     At base station  110 , the uplink signals from UE  120  and other UEs may be received by antennas  234 , processed by demodulators  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 . Base station  110  may include a scheduler  246  to schedule UEs  120  for downlink and/or uplink communications. In some aspects, a modulator and a demodulator (e.g., MOD/DEMOD  232 ) of the base station  110  may be included in a modem of the base station  110 . In some aspects, the base station  110  includes a transceiver. The transceiver may include any combination of antenna(s)  234 , modulators and/or demodulators  232 , MIMO detector  236 , receive processor  238 , transmit processor  220 , and/or TX MIMO processor  230 . The transceiver may be used by a processor (e.g., controller/processor  240 ) and memory  242  to perform aspects of any of the methods described herein (for example, as described with reference to  FIGS. 4-10 ). 
     Controller/processor  240  of base station  110 , controller/processor  280  of UE  120 , and/or any other component(s) of  FIG. 2  may perform one or more techniques associated with demodulation reference signal (DMRS) bundling for physical uplink control channel (PUCCH) repetitions, as described in more detail elsewhere herein. For example, controller/processor  240  of base station  110 , controller/processor  280  of UE  120 , and/or any other component(s) of  FIG. 2  may perform or direct operations of, for example, process  700  of  FIG. 7 , process  800  of  FIG. 8 , and/or other processes as described herein. Memories  242  and  282  may store data and program codes for base station  110  and UE  120 , respectively. In some aspects, memory  242  and/or memory  282  may include a non-transitory computer-readable medium storing one or more instructions (e.g., code and/or program code) for wireless communication. For example, the one or more instructions, when executed (e.g., directly, or after compiling, converting, and/or interpreting) by one or more processors of the base station  110  and/or the UE  120 , may cause the one or more processors, the UE  120 , and/or the base station  110  to perform or direct operations of, for example, process  700  of  FIG. 7 , process  800  of  FIG. 8 , and/or other processes as described herein. In some aspects, executing instructions may include running the instructions, converting the instructions, compiling the instructions, and/or interpreting the instructions, among other examples. 
     In some aspects, the UE  120  includes means for receiving, from a base station, an indication that DMRS bundling is to be used for channel estimation by the base station for one or more PUCCH repetitions, wherein the indication is a semi-static configuration or a dynamic indication; and/or means for transmitting, to the base station, the one or more PUCCH repetitions by maintaining a phase continuity among DMRSs of the one or more PUCCH repetitions based at least in part on receiving the indication that DMRS bundling is to be used. The means for the UE  120  to perform operations described herein may include, for example, one or more of antenna  252 , demodulator  254 , MIMO detector  256 , receive processor  258 , transmit processor  264 , TX MIMO processor  266 , modulator  254 , controller/processor  280 , or memory  282 . 
     In some aspects, the UE  120  includes means for receiving, from the base station, the semi-static configuration indicating that DMRS bundling is to be used for channel estimation by the base station for the one or more PUCCH repetitions. 
     In some aspects, the UE  120  includes means for receiving the dynamic indication that is specific to the UE that indicates that DMRS bundling is to be used for channel estimation by the base station. 
     In some aspects, the UE  120  includes means for receiving, from the base station, a group-common dynamic indication that DMRS bundling is to be used for channel estimation by the base station for the one or more PUCCH repetitions. 
     In some aspects, the UE  120  includes means for receiving, from the base station, an indication of a PUCCH repetition factor for the one or more PUCCH repetitions and the indication that DMRS bundling is to be used for channel estimation by the base station for the one or more PUCCH repetitions. 
     In some aspects, the UE  120  includes means for transmitting, to the base station, a capability message indicating a phase continuity capability of the UE. 
     In some aspects, the UE  120  includes means for receiving, from the base station, an indication of a PUCCH repetition group and an indication that DMRS bundling is to be applied by the base station across DMRSs of each PUCCH repetition included in the PUCCH repetition group. 
     In some aspects, the UE  120  includes means for receiving an indication of a number of PUCCH repetitions to be included in each PUCCH repetition group. 
     In some aspects, the UE  120  includes means for receiving an indication of a threshold amount of time between consecutive PUCCH repetitions, wherein consecutive PUCCH repetitions that have a time gap between the consecutive PUCCH repetitions that satisfies the threshold amount of time are to be included in a PUCCH repetition group. 
     In some aspects, the UE  120  includes means for transmitting a first PUCCH repetition included in a PUCCH repetition group; means for determining that a second PUCCH repetition included in the PUCCH repetition group is not to be transmitted; and/or means for transmitting a third PUCCH repetition included in the PUCCH repetition group after determining that the second PUCCH repetition included in the PUCCH repetition group is not to be transmitted, 
     In some aspects, the UE  120  includes means for receiving an indication that PUCCH repetitions that are to be transmitted by the UE using a same transmit beam are to be included in a PUCCH repetition group for DMRS bundling. 
     In some aspects, the UE  120  includes means for identifying that consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling. 
     In some aspects, the UE  120  includes means for identifying that consecutive PUCCH repetitions and non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling. 
     In some aspects, the UE  120  includes means for identifying whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling based at least in part on a phase continuity capability of the UE. 
     In some aspects, the UE  120  includes means for receiving, from the base station, an indication of whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling. 
     In some aspects, the UE  120  includes means for transmitting the one or more PUCCH repetitions based at least in part on applying one or more restrictions. 
     In some aspects, the base station  110  includes means for transmitting, to one or more UEs, an indication that DMRS bundling is to be used for channel estimation by the base station for PUCCH repetitions, where the indication is a semi-static configuration or a dynamic indication; means for receiving, from a UE of the one or more UEs, one or more PUCCH repetitions; and/or means for performing a channel estimation of an uplink channel associated with the one or more PUCCH repetitions by applying DMRS bundling among DMRSs of the one or more PUCCH repetitions. The means for the base station  110  to perform operations described herein may include, for example, one or more of transmit processor  220 , TX MIMO processor  230 , modulator  232 , antenna  234 , demodulator  232 , MIMO detector  236 , receive processor  238 , controller/processor  240 , memory  242 , or scheduler  246 . 
     In some aspects, the base station  110  includes means for aggregating the DMRSs of the one or more PUCCH repetitions; and/or means for performing the channel estimation of the uplink channel based at least in part on the aggregated DMRSs of the one or more PUCCH repetitions. 
     In some aspects, the base station  110  includes means for transmitting, to the one or more UEs, the semi-static configuration indicating that DMRS bundling is to be used for channel estimation by the base station for PUCCH repetitions. 
     In some aspects, the base station  110  includes means for transmitting, to the UE of the one or more UEs, the dynamic indication that is specific to the UE. 
     In some aspects, the base station  110  includes means for transmitting, to the one or more UEs, a group-common dynamic indication that DMRS bundling is to be used for channel estimation by the base station for PUCCH repetitions. 
     In some aspects, the base station  110  includes means for transmitting, to the one or more UEs, an indication of a PUCCH repetition factor for one or more PUCCH repetitions and the indication that DMRS bundling is to be used for channel estimation by the base station for the one or more PUCCH repetitions. 
     In some aspects, the base station  110  includes means for receiving, from the UE of the one or more UEs, a capability message indicating a phase continuity capability of the UE. 
     In some aspects, the base station  110  includes means for identifying a subset of UEs, from the set of UEs, that have indicated a sufficient phase continuity capability for DMRS bundling; and/or means for performing channel estimation by applying DMRS bundling among DMRSs of PUCCH repetitions received from the subset of UEs. 
     In some aspects, the base station  110  includes means for transmitting, to the one or more UEs, an indication of one or more PUCCH repetition groups and an indication that DMRS bundling is to be applied by the base station across DMRSs of each PUCCH repetition included in a PUCCH repetition group. 
     In some aspects, the base station  110  includes means for identifying that the one or more PUCCH repetitions are included in a same PUCCH repetition group; and/or means for applying DMRS bundling among DMRSs of the one or more PUCCH repetitions for channel estimation based at least in part on identifying that the one or more PUCCH repetitions are included in the same PUCCH repetition group. 
     In some aspects, the base station  110  includes means for transmitting an indication of a number of PUCCH repetitions to be included in each PUCCH repetition group. 
     In some aspects, the base station  110  includes means for transmitting an indication of a threshold amount of time between consecutive PUCCH repetitions, wherein consecutive PUCCH repetitions that have a time gap between the consecutive PUCCH repetitions that satisfies the threshold amount of time are to be included in a PUCCH repetition group. 
     In some aspects, the base station  110  includes means for receiving, from the UE, a first PUCCH repetition included in a PUCCH repetition group; means for determining that a second PUCCH repetition included in the PUCCH repetition group is not transmitted by the UE; and/or means for receiving, from the UE, a third PUCCH repetition included in the PUCCH repetition group after determining that the second PUCCH repetition included in the PUCCH repetition group is not transmitted. 
     In some aspects, the base station  110  includes means for determining that DMRS bundling is not to be applied among DMRSs of the first PUCCH repetition and the third PUCCH repetition. 
     In some aspects, the base station  110  includes means for performing channel estimation by applying DMRS bundling among DMRSs of first PUCCH repetition and any PUCCH repetitions included in the PUCCH repetition group that are transmitted prior to determining that the second PUCCH repetition included in the PUCCH repetition group is not transmitted; and/or means for performing channel estimation by applying DMRS bundling among DMRSs of third PUCCH repetition and any PUCCH repetitions included in the PUCCH repetition group that are transmitted after determining that the second PUCCH repetition included in the PUCCH repetition group is not transmitted. 
     In some aspects, the base station  110  includes means for transmitting an indication that PUCCH repetitions that are to be transmitted by a UE using a same transmit beam are to be included in a PUCCH repetition group for DMRS bundling. 
     In some aspects, the base station  110  includes means for identifying whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling. 
     In some aspects, the base station  110  includes means for determining whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group based at least in part on a phase continuity capability of the UE. 
     In some aspects, the base station  110  includes means for transmitting, to the UE, an indication of whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling. 
     While blocks in  FIG. 2  are illustrated as distinct components, the functions described above with respect to the blocks may be implemented in a single hardware, software, or combination component or in various combinations of components. For example, the functions described with respect to the transmit processor  264 , the receive processor  258 , and/or the TX MIMO processor  266  may be performed by or under the control of controller/processor  280 . 
     As indicated above,  FIG. 2  is provided as an example. Other examples may differ from what is described with regard to  FIG. 2 . 
       FIG. 3  is a diagram illustrating an example  300  of a frame structure in a wireless communication network, in accordance with the present disclosure. The frame structure shown in  FIG. 3  is for frequency division duplexing (FDD) in a telecommunication system, such as LTE or NR. The transmission timeline for each of the downlink and uplink may be partitioned into units of radio frames (sometimes referred to as frames). Each radio frame may have a predetermined duration (e.g., 10 milliseconds (ms)) and may be partitioned into a set of Z (Z≥1) subframes (e.g., with indices of 0 through Z−1). Each subframe may have a predetermined duration (e.g., 1 ms) and may include a set of slots (e.g., 2m slots per subframe are shown in  FIG. 3 , where m is an index of a numerology used for a transmission, such as 0, 1, 2, 3, 4, or another number). Each slot may include a set of L symbol periods. For example, each slot may include fourteen symbol periods (e.g., as shown in  FIG. 3 ), seven symbol periods, or another number of symbol periods. In a case where the subframe includes two slots (e.g., when m=1), the subframe may include 2L symbol periods, where the 2L symbol periods in each subframe may be assigned indices of 0 through 2L−1. In some aspects, a scheduling unit for the FDD may be frame-based, subframe-based, slot-based, mini-slot based, or symbol-based. 
     As indicated above,  FIG. 3  is provided as an example. Other examples may differ from what is described with respect to  FIG. 3 . 
     In some cases, a transmitter, such as a UE  120  or a base station  110 , may transmit one or more DMRSs to a receiver, such as another UE  120  or base station  110 . A DMRS may include a reference signal that is generated from a base sequence, such as a Zadoff-Chu sequence or a Gold sequence. A DMRS may carry information used to estimate a radio channel for demodulation of an associated physical channel. The design and mapping of a DMRS may be specific to a physical channel for which the DMRS is used for estimation. DMRSs are UE-specific, can be beamformed, can be confined in a scheduled resource (e.g., rather than transmitted on a wideband), and can be transmitted only when necessary. DMRSs are used for both downlink communications and uplink communications. The receiver may perform one or more measurements of the DMRS to estimate a physical channel on which one or more communications are transmitted from the transmitter. In this way, the receiver may determine whether a channel quality of the physical channel satisfies one or more channel quality thresholds and may use the results from the one or more measurements to facilitate demodulation of the communications transmitted on the physical channel. 
     In some cases, the transmitter and/or receiver may support bundling of DMRSs in the time domain across one or more time slots. That is, when DMRS bundling is configured, the receiver may perform joint or aggregated channel estimation based on DMRS(s) received across multiple slots, as opposed to performing channel estimation separately for each individual slot based on the DMRS(s) received in that slot. DMRS bundling may be referred to as DMRS aggregation. DMRS bundling enables the receiver to perform joint channel estimation on the DMRS in multiple time slots to improve an accuracy of channel estimation. 
     For DMRS bundling to be supported, the transmitter may be required to maintain a phase continuity or phase coherence among the DMRSs transmitted by the transmitter. “Phase continuity” or “phase coherence” may refer to the transmitter maintaining a radio frequency (RF) phase after modulation among multiple transmissions (e.g., among multiple DMRSs) over time. For example, to maintain continuity or phase coherence among DMRSs, the transmitter may maintain a consistency in a phase relationship among multiple DMRSs transmitted in different time slots. Phase continuity or phase coherence among the DMRSs transmitted by the transmitter may be required for DMRS bundling to allow the receiver to aggregate or bundle the DMRSs to perform joint channel estimation based on DMRS(s) received across multiple slots. A failure to maintain phase continuity or phase coherence among the DMRSs may result in the receiver being unable to perform a channel estimation, or may result in an inaccurate channel estimation, when applying DMRS bundling. 
     In some cases, a UE  120  may be configured to transmit one or more PUCCH repetitions of a PUCCH communication. For example, the UE  120  may be configured to transmit multiple PUCCH repetitions across different time slots. In some aspects, a PUCCH format of a PUCCH communication may indicate a number of repetitions associated with the PUCCH communication (e.g., a repetition factor). A PUCCH repetition may include one or more DMRSs. Therefore, it may be beneficial for a base station  110  to perform DMRS bundling across DMRSs of PUCCH repetitions to improve an accuracy of a channel estimation of the uplink channel. However, the UE  120  may be unaware of which PUCCH repetitions are to be associated with DMRS bundling and/or may be unaware that the base station  110  is to apply DMRS bundling across DMRSs of multiple PUCCH repetitions. Therefore, the UE  120  may not maintain phase continuity or phase coherence across the PUCCH repetitions. Moreover, some UEs  120  may be unable to support or maintain phase continuity or phase coherence across the multiple PUCCH repetitions (e.g., due to a lack of capability of the UE  120  or an RF hardware configuration of the UE  120 ). As a result, a UE  120  may not maintain phase continuity or phase coherence across the multiple PUCCH repetitions, resulting in the base station  110  being unable to perform a channel estimation, or resulting in an inaccurate channel estimation, by applying DMRS bundling among DMRSs of the multiple PUCCH repetitions. This may result in decreased demodulation performance by the base station  110 . 
     Some techniques and apparatuses described herein enable DMRS bundling for PUCCH repetitions. A base station  110  may indicate, to one or more UEs  120 , that the base station  110  is to apply DMRS bundling across one or more PUCCH repetitions. For example, PUCCH repetitions may be grouped into repetition groups, enabling a UE  120  to identify that phase continuity should be maintained among DMRSs of PUCCH repetitions included in a repetition group. The UE  120  may transmit one or more PUCCH repetitions (e.g., PUCCH repetitions included in a repetition group) by maintaining a phase continuity among DMRSs of the one or more PUCCH repetitions. The base station  110  may receive the one or more PUCCH repetitions. The base station  110  may perform a channel estimation of an uplink channel associated with the one or more PUCCH repetitions by applying DMRS bundling among DMRSs of the one or more PUCCH repetitions. As a result, the UE  120  is enabled to identify PUCCH repetitions that are associated with DMRS bundling and may ensure that a phase continuity among DMRSs of the PUCCH repetitions is maintained by the UE  120 . This enables the base station  110  to apply DMRS bundling among the DMRSs of the PUCCH repetitions, improving an accuracy of channel estimation by the base station  110 . 
       FIG. 4  is a diagram illustrating an example  400  associated with DMRS bundling for PUCCH repetitions, in accordance with the present disclosure. As shown in  FIG. 4 , a base station  110  and a UE  120  may communicate with one another. In some aspects, the base station  110  and the UE  120  may be included in a wireless network, such as wireless network  100 . The base station  110  and the UE  120  may communicate via a wireless access link, which may include an uplink and a downlink. 
     As shown by reference number  405 , the base station  110  may transmit, and the UE  120  may receive, an indication that DMRS bundling is to be used for channel estimation by the base station  110  for PUCCH repetitions. In some aspects, the indication that DMRS bundling is to be used for channel estimation by the base station  110  for PUCCH repetitions may be an indication to the UE  120  to apply phase continuity among DMRSs of one or more PUCCH repetitions (e.g., to enable the base station  110  to apply DMRS bundling among the DMRSs of the one or more PUCCH repetitions). 
     In some aspects, the indication that DMRS bundling is to be used for channel estimation by the base station  110  for PUCCH repetitions may be included in a semi-static configuration transmitted by the base station  110 . In some aspects, the indication that DMRS bundling is to be used for channel estimation by the base station  110  for PUCCH repetitions may be included in a dynamic indication transmitted by the base station  110 . 
     In some aspects, the base station  110  may transmit the indication that DMRS bundling is to be used for channel estimation by the base station  110  for PUCCH repetitions to one or more UEs  120 . For example, the indication may be a group-common indication that is transmitted to multiple UEs  120 . In some aspects, the indication that DMRS bundling is to be used for channel estimation by the base station  110  for PUCCH repetitions may be a UE-specific indication (e.g., the indication may be transmitted to a single UE  120 ). In some aspects, the base station  110  may transmit the indication that DMRS bundling is to be used for channel estimation by the base station  110  for PUCCH repetitions in a downlink control information (DCI) message (e.g., a dynamic indication). In some aspects, the base station  110  may transmit the indication that DMRS bundling is to be used for channel estimation by the base station  110  for PUCCH repetitions in a medium access control (MAC) control element (MAC-CE) message (e.g., a semi-static configuration). 
     In some aspects, the base station  110  may transmit, to the UE  120 , an indication of a PUCCH repetition factor. The PUCCH repetition factor may indicate a number of repetitions associated with the PUCCH communication. The indication of the PUCCH repetition factor may be a dynamic indication transmitted by the base station  110 . In some aspects, the base station  110  may transmit the indication of the PUCCH repetition factor and the indication that DMRS bundling is to be used for channel estimation by the base station  110  for PUCCH repetitions in the same message (e.g., as part of the same dynamic indication). 
     As shown by reference number  410 , in some aspects, the UE  120  may transmit, and the base station  110  may receive, a capability message that indicates a phase continuity capability of the UE  120 . The phase continuity capability may indicate whether the UE  120  can support phase continuity across DMRSs of multiple PUCCH repetitions. In some aspects, the phase continuity capability may indicate an amount of time that the UE  120  can maintain phase continuity across multiple transmissions. In some aspects, the phase continuity capability may indicate one or more antennas of the UE  120  across which phase continuity can be maintained (e.g., the UE  120  may be capable of maintaining phase continuity among transmissions using a first antenna and a third antenna, but may not be capable of maintaining phase continuity among transmissions using the first antenna and a second antenna). 
     In some aspects, the phase continuity capability may indicate whether the UE  120  is capable of maintaining phase continuity among non-consecutive transmissions that use the same transmit beam or precoder. For example, the UE  120  may communicate using a beam A and a beam B. The phase continuity capability may indicate whether the UE  120  is capable of maintaining phase continuity among transmissions on beam A if the UE  120  is to transmit a communication on beam B between the transmissions on beam A. That is, if transmissions by the UE  120  have an order in the time domain of a first transmission on beam A, a second transmission on beam B, and a third transmission on beam A, then the phase continuity capability may indicate whether the UE  120  is capable of maintaining phase continuity among the first transmission and the third transmission. 
     In some aspects, the base station  110  may determine whether to apply DMRS bundling to PUCCH repetitions transmitted by a UE  120  based at least in part on a reported phase continuity capability of the UE  120 . For example, in some aspects, the base station  110  may transmit a group-common indication, to a set of UEs  120 , that DMRS bundling is to be used for channel estimation by the base station  110  for PUCCH repetitions. The base station  110  may receive, from one or more (or all) of the set of UEs  120 , a phase continuity capability message. The base station  110  may identify a subset of UEs  120 , from the set of UEs  120 , that have indicated a sufficient phase continuity capability for DMRS bundling. The base station  110  may perform channel estimation by applying DMRS bundling among DMRSs of PUCCH repetitions received from the subset of UEs  120 , as described below in more detail. 
     As shown by reference number  415 , the UE  120  may identify one or more PUCCH repetitions that are associated with DMRS bundling. For example, the UE  120  may identify one or more PUCCH repetitions for which the UE  120  is to maintain a phase continuity for DMRSs of the PUCCH repetitions (e.g., to enable the base station  110  to apply DMRS bundling among the DMRSs of the one or more PUCCH repetitions). 
     In some aspects, the UE  120  may identify one or more PUCCH repetition groups. A PUCCH repetition group may be a set of PUCCH repetitions for which the UE  120  is to apply phase continuity among DMRSs of the set of PUCCH repetitions. In other words, a PUCCH repetition group may be a set of PUCCH repetitions that the base station  110  is to apply DMRS bundling to for channel estimation. 
     In some aspects, the base station  110  may indicate the one or more PUCCH repetition groups when indicating that DMRS bundling is to be used for channel estimation by the base station  110  for PUCCH repetitions. In some aspects, the base station  110  may indicate the one or more PUCCH repetition groups in a separate indication or configuration. In some aspects, the base station  110  may indicate, to the UE  120 , one or more parameters for forming PUCCH repetition groups. For example, a parameter for forming PUCCH repetition groups may include a number of PUCCH repetitions to be included in a PUCCH repetition group. For example, the base station  110  may indicate that every NPUCCH repetitions are to be included in a PUCCH repetition group, where Nis an integer. In some aspects, a parameter for forming PUCCH repetition groups may include a threshold time gap between consecutive repetitions. That is, the UE  120  may identify a time gap between consecutive PUCCH repetitions. If the time gap does not satisfy (e.g., is larger than) the threshold time gap, then the consecutive PUCCH repetitions are not to be included in the same PUCCH repetition group. For example, the base station  110  may indicate that consecutive PUCCH repetitions, that have a time gap between the PUCCH repetitions that does not satisfy (e.g., is larger than) the threshold time gap, are not to be included in the same PUCCH repetition group. 
     In some aspects, a parameter for forming PUCCH repetition groups may include a beam used to transmit the PUCCH repetition. For example, PUCCH repetitions may be transmitted, by the UE  120 , using multiple beams or precoders. The parameter for forming PUCCH repetition groups may indicate whether non-consecutive PUCCH repetitions that are to be transmitted by the UE  120  using the same transmit beam are to be included in the same PUCCH repetition group. In some aspects, the parameter for forming PUCCH repetition groups may indicate that only consecutive PUCCH repetitions that are to be transmitted by the UE  120  using the same transmit beam are to be included in the same PUCCH repetition group. In some aspects, the parameter for forming PUCCH repetition groups may indicate that consecutive and non-consecutive PUCCH repetitions that are to be transmitted by the UE  120  using the same transmit beam are to be included in the same PUCCH repetition group. 
     For example, a beam pattern for PUCCH repetitions may be beam A, followed by beam B, followed by beam A, and followed by beam B. If only consecutive PUCCH repetitions that are to be transmitted by the UE  120  using the same transmit beam are to be included in the same PUCCH repetition group, then none of the PUCCH repetitions following the above pattern may be included in the same PUCCH repetition group. However, if consecutive and non-consecutive PUCCH repetitions that are to be transmitted by the UE  120  using the same transmit beam are to be included in the same PUCCH repetition group, then the PUCCH repetitions transmitted using beam A may be included in a first PUCCH repetition group and the PUCCH repetitions transmitted using beam B may be included in a second PUCCH repetition group. 
     In some aspects, whether non-consecutive PUCCH repetitions that are to be transmitted by the UE  120  using the same transmit beam are to be included in the same PUCCH repetition group may be based at least in part on the phase continuity capability of the UE  120 . In some aspects, whether non-consecutive PUCCH repetitions that are to be transmitted by the UE  120  using the same transmit beam are to be included in the same PUCCH repetition group may be indicated by the base station  110  to the UE  120  (e.g., in a semi-static configuration or using dynamic signaling). 
     The UE  120  may identify PUCCH repetition groups using one or more (or all) of the parameters described above. For example, the UE  120  may identify a PUCCH repetition group (e.g., based at least in part on one or more (or all) of the parameters described above) and may determine that the UE  120  is to maintain a phase continuity or phase coherence among DMRSs of the PUCCH repetitions included in the PUCCH repetition group. 
     As shown by reference number  420 , the UE  120  may transmit, to the base station  110 , one or more PUCCH repetitions by maintaining a phase continuity among DMRSs of the one or more PUCCH repetitions (e.g., based at least in part on receiving the indication that DMRS bundling is to be used). For example, the UE  120  may determine whether the phase continuity capability of the UE  120  is sufficient for maintaining a phase continuity among DMRSs of the one or more PUCCH repetitions. The UE  120  may identify one or more PUCCH repetitions for which a phase continuity among DMRSs of the one or more PUCCH repetitions is to be maintained (e.g., based at least in part on identifying a PUCCH repetition group, as described above). The UE  120  may ensure that an RF phase of the DMRSs of the one or more PUCCH repetitions (e.g., the PUCCH repetitions included in the PUCCH repetition group) is maintained while transmitting the one or more PUCCH repetitions. For example, the UE  120  may transmit the one or more PUCCH repetitions in separate transmissions and/or in separate time slots. The UE  120  may ensure that an RF phase of the DMRSs among each transmission for the one or more PUCCH repetitions is maintained. 
     In some aspects, the UE  120  may apply one or more restrictions to the transmission of the one or more PUCCH repetitions based at least in part on receiving the indication that DMRS bundling is to be used. For example, the one or more restrictions may include that phase continuity is to be maintained among the one or more PUCCH repetitions. As another example, the one or more restrictions may include that the UE  120  is to refrain from transmitting another uplink communication between the one or more PUCCH repetitions (e.g., between PUCCH repetitions included in a PUCCH repetition group). In other words, based at least in part on receiving the indication that DMRS bundling is to be used, the UE  120  may refrain from transmitting another uplink communication between a first time associated with a transmission a first PUCCH repetition and a second time associated a second transmission of a second PUCCH repetition (e.g., where DMRS bundling is to be applied among the first PUCCH repetition and the second PUCCH repetition). As another example, the one or more restrictions may include that the UE  120  is to use a certain beam pattern or precoder pattern for the transmissions of the one or more PUCCH repetitions (e.g., as depicted and described in more detail in connection with  FIG. 6 ). The one or more restrictions may ensure, or improve a likelihood, that DMRS bundling may be successfully applied by the base station  110 . 
     As shown by reference number  425 , the base station  110  may determine whether to apply DMRS bundling to PUCCH repetitions received from the UE  120 . For example, the base station  110  may determine whether to apply DMRS bundling to PUCCH repetitions received from the UE  120  based at least in part on the phase continuity capability of the UE  120 . The base station  110  may determine whether to apply DMRS bundling to PUCCH repetitions received from the UE  120  based at least in part on determining whether the PUCCH repetitions are included in the same PUCCH repetition group (e.g., in a similar manner as described above in connection with the UE  120  identifying the PUCCH repetition groups). 
     In some aspects, the UE  120  may not transmit a PUCCH repetition included in a PUCCH repetition group. For example, the UE  120  may drop (e.g., not transmit) a PUCCH repetition due to an overlap (e.g., in the time domain) with a downlink signal or a downlink symbol. In some aspects, the UE  120  may drop a PUCCH repetition due to a cancellation indication received from the base station  110 . In some aspects, the UE  120  may drop a PUCCH repetition due to an overlap (e.g., in the time domain) with another uplink signal, such as a sounding reference signal (SRS). For example, the UE  120  may drop the PUCCH repetition and transmit the other uplink signal. In some other aspects, if the UE  120  determines that the PUCCH repetition overlaps (e.g., in the time domain) with another uplink signal, or that another uplink signal is to be transmitted between another PUCCH repetition and the PUCCH repetition, the UE  120  may refrain from transmitting the other uplink signal and may transmit the PUCCH repetition. The base station  110  may determine that DMRS bundling is not to be applied among DMRSs of PUCCH repetitions transmitted before the dropped repetition and DMRSs of PUCCH repetitions transmitted after the dropped repetition. The base station  110  may determine that DMRS bundling is not to be applied in this scenario as the reception of a downlink signal or transmission of another uplink signal between transmissions of PUCCH repetitions may cause the UE  120  to be unable to maintain a phase continuity among the PUCCH repetitions. 
     For example, a PUCCH repetition group may include three PUCCH repetitions. The UE  120  may transmit, to the base station  110 , the first PUCCH repetition (e.g., the first PUCCH repetition in the time domain). The UE  120  may drop (e.g., not transmit) the second PUCCH repetition. The UE  120  may transmit, to the base station  110 , the third PUCCH repetition (e.g., the third PUCCH repetition in the time domain). The base station  110  may determine that DMRS bundling is not to be applied among a DMRS of the first PUCCH repetition and a DMRS of the third PUCCH repetition. 
     In the example above, if the PUCCH repetition group includes additional PUCCH repetitions (e.g., before the first PUCCH repetition in the time domain or after the third PUCCH repetition in the time domain), then the base station  110  may determine that DMRS bundling is to be applied among DMRSs of PUCCH repetitions transmitted before the second PUCCH repetition is dropped or among DMRSs of PUCCH repetitions transmitted after the second PUCCH repetition is dropped. 
     As shown by reference number  430 , the base station  110  may perform a channel estimation of an uplink channel associated with the one or more PUCCH repetitions by applying DMRS bundling among DMRSs of the one or more PUCCH repetitions. For example, the base station  110  may perform a joint channel estimation using the DMRSs of the one or more PUCCH repetitions that are transmitted across multiple time slots. 
     As a result, the UE  120  is enabled to identify PUCCH repetitions that are associated with DMRS bundling and may ensure that a phase continuity among DMRSs of the PUCCH repetitions is maintained by the UE  120 . This enables the base station  110  to apply DMRS bundling among the DMRSs of the PUCCH repetitions, improving an accuracy of channel estimation by the base station  110 . 
     As indicated above,  FIG. 4  is provided as an example. Other examples may differ from what is described with respect to  FIG. 4 . 
       FIG. 5  is a diagram illustrating an example  500  associated with DMRS bundling for PUCCH repetitions, in accordance with the present disclosure. As shown in  FIG. 5 , a base station  110  and a UE  120  may communicate with one another. 
     As shown by reference numbers  505  and  510 , the UE  120  may identify (or be scheduled or configured with) PUCCH repetition groups. As described above in connection with  FIG. 4 , a PUCCH repetition group may include PUCCH repetitions among which the base station  110  is to apply DMRS bundling for channel estimation. The UE  120  and/or the base station  110  may identify the PUCCH repetition groups in a similar (or the same) manner as described above in connection with  FIG. 4 . For example, the UE  120  and/or the base station  110  may identify the PUCCH repetition groups based at least in part on one or more (or all) of the parameters for forming PUCCH repetition groups described above in connection with  FIG. 4 . 
     As shown by reference number  515 , the UE  120  may transmit each PUCCH repetition included in the PUCCH repetition group. The UE  120  may transmit the PUCCH repetitions by maintaining a phase continuity or a phase coherence among DMRSs of each PUCCH repetition included in the PUCCH repetition group. As shown by reference number  520 , the base station  110  may perform a channel estimation of an uplink channel associated with the PUCCH repetitions by applying DMRS bundling among DMRSs of each PUCCH repetition included in the PUCCH repetition group. 
     As shown in  FIG. 5 , the UE  120  may attempt to transmit each PUCCH repetition included in the PUCCH repetition group shown by reference number  510 . For example, the UE  120  may attempt to maintain a phase continuity or a phase coherence among DMRSs of each PUCCH repetition included in the PUCCH repetition group. As shown by reference number  525 , the UE  120  may transmit, to the base station  110 , a first PUCCH repetition included in the PUCCH repetition group. 
     As shown by reference number  530 , the UE  120  may determine that a second PUCCH repetition included in the PUCCH repetition group is not to be transmitted. For example, the UE  120  may identify an overlap (e.g., in the time domain) with a downlink signal from the base station  110  or a downlink symbol. Alternatively, the UE  120  may determine that another uplink signal, such as an SRS, is to be transmitted by the UE  120  that overlaps (e.g., in the time domain) with the second PUCCH repetition. In some aspects, if the UE  120  determines that the second PUCCH repetition overlaps (e.g., in the time domain) with another uplink signal, or that another uplink signal is to be transmitted between the first PUCCH repetition and the second PUCCH repetition, the UE  120  may refrain from transmitting the other uplink signal and may transmit the second PUCCH repetition. As a result, the UE  120  may drop (e.g., not transmit) the second PUCCH repetition included in the PUCCH repetition group. As shown by reference number  535 , the UE  120  may transmit, to the base station  110 , a third PUCCH repetition included in the PUCCH repetition group. 
     As shown by reference number  540 , the base station  110  may receive the first PUCCH repetition and the third PUCCH repetition from the UE  120 . However, the base station  110  may refrain from applying DMRS bundling among DMRSs of the first PUCCH repetition and the third PUCCH repetition. Failing to transmit a PUCCH repetition included in the PUCCH repetition group (e.g., the second PUCCH repetition), may break the PUCCH repetition group. That is, the base station  110  may not apply DMRS bundling among DMRSs of PUCCH repetitions transmitted before the dropped PUCCH repetition (e.g., the first PUCCH repetition) and DMRSs of PUCCH repetitions transmitted after the dropped PUCCH repetition (e.g., the third PUCCH repetition). 
     In some cases, the PUCCH repetition group may be maintained for PUCCH repetitions transmitted before the dropped PUCCH repetition. For example, if the PUCCH repetition group included another PUCCH repetition before the first PUCCH repetition (e.g., in the time domain), then the base station  110  may perform a channel estimation of an uplink channel associated with the PUCCH repetitions by applying DMRS bundling among DMRSs of the other PUCCH repetition and the first PUCCH repetition (e.g., but not the third PUCCH repetition). Similarly, the PUCCH repetition group may be maintained for PUCCH repetitions transmitted after the dropped PUCCH repetition. For example, if the PUCCH repetition group included another PUCCH repetition after the third PUCCH repetition (e.g., in the time domain), then the base station  110  may perform a channel estimation of an uplink channel associated with the PUCCH repetitions by applying DMRS bundling among DMRSs of the other PUCCH repetition and the third PUCCH repetition (e.g., but not the first PUCCH repetition). 
     The base station  110  may not apply DMRS bundling in this scenario as the reception of a downlink signal or transmission of another uplink signal between transmissions of PUCCH repetitions may cause the UE  120  to be unable to maintain a phase continuity among the PUCCH repetitions. In this way, the base station  110  may ensure that DMRS bundling is applied only among DMRSs for which the UE  120  is capable of maintaining a phase continuity or phase coherence. This may improve an accuracy of a channel estimation by the base station  110  when applying DMRS bundling. 
     As indicated above,  FIG. 5  is provided as an example. Other examples may differ from what is described with respect to  FIG. 5 . 
       FIG. 6  is a diagram illustrating examples  600  and  650  associated with DMRS bundling for PUCCH repetitions, in accordance with the present disclosure. As shown in  FIG. 6 , a UE  120  may identify one or more PUCCH repetition groups based at least in part on a transmit beam or precoder used by the UE  120  to transmit PUCCH repetitions. 
     As shown in  FIG. 6 , and example  600 , the UE  120  may transmit PUCCH repetitions using multiple transmit beams (e.g., shown as beam A and beam B in  FIG. 6 ). Example  600  may depict PUCCH repetition groups formed based at least in part on a transmit beam used by the UE  120 , where only consecutive PUCCH repetitions transmitted on the same transmit beam are to be included in the same PUCCH repetition group. For example, the UE  120  may transmit a PUCCH repetition  605  and a PUCCH repetition  610  on beam A, as shown in  FIG. 6 . The UE  120  may transmit a PUCCH repetition  615  and a PUCCH repetition  620  on beam B. The UE  120  may transmit a PUCCH repetition  625  and a PUCCH repetition  630  on beam A. 
     As shown by reference number  635 , PUCCH repetition  605  and PUCCH repetition  610  may be included in the same PUCCH repetition group, as they are PUCCH repetitions transmitted consecutively (e.g., in the time domain) on the same transmit beam (e.g., beam A). As shown by reference number  640 , PUCCH repetition  615  and PUCCH repetition  620  may be included in the same PUCCH repetition group as they are PUCCH repetitions transmitted consecutively (e.g., in the time domain) on the same transmit beam (e.g., beam B). Similarly, as shown by reference number  645 , PUCCH repetition  625  and PUCCH repetition  630  may be included in the same PUCCH repetition group as they are PUCCH repetitions transmitted consecutively (e.g., in the time domain) on the same transmit beam (e.g., beam A). However, in some cases, even though PUCCH repetition  610  and PUCCH repetition  625  are transmitted on the same beam (e.g., beam A), they may not be included in the same PUCCH repetition group as they are not consecutive (e.g., PUCCH repetitions  615  and  620  are transmitted on beam B between PUCCH repetition  610  and PUCCH repetition  625 ). In some aspects, the UE  120  may identify the PUCCH repetition groups as described above in example  600  and based at least in part on one or more other parameters for forming PUCCH repetition groups described above in connection with  FIGS. 4 and 5 . 
     As shown in  FIG. 6 , and example  600 , the UE  120  may transmit PUCCH repetitions using multiple transmit beams (e.g., shown as beam A and beam B in  FIG. 6 ). Example  600  may depict PUCCH repetition groups formed based at least in part on a transmit beam used by the UE  120  where both consecutive and non-consecutive PUCCH repetitions may be included in the same PUCCH repetition group so long as the PUCCH repetitions are transmitted using the same transmit beam. For example, the UE  120  may transmit a PUCCH repetition  655  on beam A. The UE  120  may transmit a PUCCH repetition  660  on beam B. The UE  120  may transmit a PUCCH repetition  665  on beam A. The UE  120  may transmit a PUCCH repetition  670  on beam B. 
     As shown by reference number  675 , PUCCH repetition  655  and PUCCH repetition  665  may be included in the same PUCCH repetition group because PUCCH repetition  655  and PUCCH repetition  665  are transmitted by the UE  120  using beam A. Similarly, as shown by reference number  680 , PUCCH repetition  660  and PUCCH repetition  670  may be included in the same PUCCH repetition group because PUCCH repetition  660  and PUCCH repetition  670  are transmitted by the UE  120  using beam B. In some aspects, the UE  120  may identify the PUCCH repetition groups as described above in example  650  and based at least in part on one or more other parameters for forming PUCCH repetition groups described above in connection with  FIGS. 4 and 5 . 
     In some aspects, whether PUCCH repetition groups are formed in accordance with example  600  (e.g., where only consecutive PUCCH repetitions transmitted on the same transmit beam are to be included in the same PUCCH repetition group) or in accordance with example  650  (e.g., where PUCCH repetitions transmitted on the same transmit beam are to be included in the same PUCCH repetition group regardless of whether the PUCCH repetitions are consecutive) may be based at least in part on a phase continuity capability of the UE  120 . In some aspects, whether PUCCH repetition groups are formed in accordance with example  600  or in accordance with example  650  may be based at least in part on an indication, to the UE  120 , from a base station  110  (e.g., a dynamic indication or a semi-static configuration). 
     As indicated above,  FIG. 6  is provided as an example. Other examples may differ from what is described with respect to  FIG. 6 . 
       FIG. 7  is a diagram illustrating an example process  700  performed, for example, by a UE, in accordance with the present disclosure. Example process  700  is an example where the UE (e.g., UE  120 ) performs operations associated with DMRS bundling for PUCCH repetitions. 
     As shown in  FIG. 7 , in some aspects, process  700  may include receiving, from a base station, an indication that DMRS bundling is to be used for channel estimation by the base station for one or more PUCCH repetitions, wherein the indication is a semi-static configuration or a dynamic indication (block  710 ). For example, the UE (e.g., using reception component  902 , depicted in  FIG. 9 ) may receive, from a base station, an indication that DMRS bundling is to be used for channel estimation by the base station for one or more PUCCH repetitions, wherein the indication is a semi-static configuration or a dynamic indication, as described above. 
     As further shown in  FIG. 7 , in some aspects, process  700  may include transmitting, to the base station, the one or more PUCCH repetitions by maintaining a phase continuity among DMRSs of the one or more PUCCH repetitions based at least in part on receiving the indication that DMRS bundling is to be used (block  720 ). For example, the UE (e.g., using transmission component  904 , depicted in  FIG. 9 ) may transmit, to the base station, the one or more PUCCH repetitions by maintaining a phase continuity among DMRSs of the one or more PUCCH repetitions based at least in part on receiving the indication that DMRS bundling is to be used, as described above. 
     Process  700  may include additional aspects, such as any single aspect or any combination of aspects described below and/or in connection with one or more other processes described elsewhere herein. 
     In a first aspect, receiving the indication that DMRS bundling is to be used for channel estimation by the base station comprises receiving, from the base station, the semi-static configuration indicating that DMRS bundling is to be used for channel estimation by the base station for the one or more PUCCH repetitions. 
     In a second aspect, receiving the indication that DMRS bundling is to be used for channel estimation by the base station comprises receiving the dynamic indication, wherein the dynamic indication is specific to the UE. 
     In a third aspect, receiving the indication that DMRS bundling is to be used for channel estimation by the base station comprises receiving, from the base station, a group-common dynamic indication that DMRS bundling is to be used for channel estimation by the base station for the one or more PUCCH repetitions. 
     In a fourth aspect, alone or in combination with one or more of the first through third aspects, receiving the indication that DMRS bundling is to be used for channel estimation by the base station comprises receiving the indication via a DCI message. 
     In a fifth aspect, alone or in combination with one or more of the first through third aspects, receiving the indication that DMRS bundling is to be used for channel estimation by the base station comprises receiving the indication via a MAC-CE message. 
     In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, receiving the indication that DMRS bundling is to be used for channel estimation by the base station comprises receiving, from the base station, an indication of a PUCCH repetition factor for the one or more PUCCH repetitions and the indication that DMRS bundling is to be used for channel estimation by the base station for the one or more PUCCH repetitions. 
     In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, process  700  includes transmitting, to the base station, a capability message indicating a phase continuity capability of the UE. 
     In an eighth aspect, alone or in combination with one or more of the third through seventh aspects, the indication that DMRS bundling is to be used for channel estimation by the base station is a group-common indication associated with a set of UEs, that includes the UE, and the base station applies DMRS bundling to PUCCH repetitions transmitted by a subset of UEs, from the set of UEs, that have a sufficient phase continuity capability. 
     In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, receiving the indication that DMRS bundling is to be used for channel estimation by the base station comprises receiving, from the base station, an indication of a PUCCH repetition group and an indication that DMRS bundling is to be applied by the base station across DMRSs of each PUCCH repetition included in the PUCCH repetition group. 
     In a tenth aspect, alone or in combination with the ninth aspect, receiving the indication of the PUCCH repetition group comprises receiving an indication of a number of PUCCH repetitions to be included in each PUCCH repetition group. 
     In an eleventh aspect, alone or in combination with one or more of the ninth through tenth aspects, receiving the indication of the PUCCH repetition group comprises receiving an indication of a threshold amount of time between consecutive PUCCH repetitions, wherein consecutive PUCCH repetitions that have a time gap between the consecutive PUCCH repetitions that satisfies the threshold amount of time are to be included in a PUCCH repetition group. 
     In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, transmitting the one or more PUCCH repetitions comprises transmitting a first PUCCH repetition included in a PUCCH repetition group, determining that a second PUCCH repetition included in the PUCCH repetition group is not to be transmitted, and transmitting a third PUCCH repetition included in the PUCCH repetition group after determining that the second PUCCH repetition included in the PUCCH repetition group is not to be transmitted, wherein DMRS bundling is not to be applied by the base station among DMRSs of the first PUCCH repetition and the third PUCCH repetition. 
     In a thirteenth aspect, alone or in combination with the twelfth aspect, DMRS bundling is to be applied by the base station among DMRSs of the first PUCCH repetition and any PUCCH repetitions included in the PUCCH repetition group that are transmitted prior to determining that the second PUCCH repetition included in the PUCCH repetition group is not to be transmitted. 
     In a fourteenth aspect, alone or in combination with one or more of the first through thirteenth aspects, receiving the indication that DMRS bundling is to be used for channel estimation by the base station comprises receiving an indication that PUCCH repetitions that are to be transmitted by the UE using a same transmit beam are to be included in a PUCCH repetition group for DMRS bundling. 
     In a fifteenth aspect, alone or in combination with the fourteenth aspect, receiving the indication that PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling comprises identifying that consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling. 
     In a sixteenth aspect, alone or in combination with the fourteenth aspect, receiving the indication that PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling comprises identifying that consecutive PUCCH repetitions and non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling. 
     In a seventeenth aspect, alone or in combination with one or more of the fourteenth through sixteenth aspects, process  700  includes identifying whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling based at least in part on a phase continuity capability of the UE. 
     In an eighteenth aspect, alone or in combination with one or more of the fourteenth through sixteenth aspects, process  700  includes receiving, from the base station, an indication of whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling. 
     In a nineteenth aspect, alone or in combination with one or more of the first through eighteenth aspects, transmitting the one or more PUCCH repetitions includes applying one or more restrictions based at least in part on receiving the indication that DMRS bundling is to be used. 
     In a twentieth aspect, alone or in combination with the nineteenth aspect, the one or more restrictions include at least one of: refraining from transmitting another uplink signal between repetitions of the one or more PUCCH repetitions, maintaining the phase continuity among the DMRSs of the one or more PUCCH repetitions, or using a beam pattern or precoder pattern when transmitting the one or more PUCCH repetitions. 
     Although  FIG. 7  shows example blocks of process  700 , in some aspects, process  700  may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in  FIG. 7 . Additionally, or alternatively, two or more of the blocks of process  700  may be performed in parallel. 
       FIG. 8  is a diagram illustrating an example process  800  performed, for example, by a base station, in accordance with the present disclosure. Example process  800  is an example where the base station (e.g., base station  110 ) performs operations associated with DMRS bundling for PUCCH repetitions. 
     As shown in  FIG. 8 , in some aspects, process  800  may include transmitting, to one or more UEs, an indication that DMRS bundling is to be used for channel estimation by the base station for PUCCH repetitions, wherein the indication is a semi-static configuration or a dynamic indication (block  810 ). For example, the base station (e.g., using transmission component  1004 , depicted in  FIG. 10 ) may transmit, to one or more UEs, an indication that DMRS bundling is to be used for channel estimation by the base station for PUCCH repetitions, wherein the indication is a semi-static configuration or a dynamic indication, as described above. 
     As further shown in  FIG. 8 , in some aspects, process  800  may include receiving, from a UE of the one or more UEs, one or more PUCCH repetitions (block  820 ). For example, the base station (e.g., using reception component  1002 , depicted in  FIG. 10 ) may receive, from a UE of the one or more UEs, one or more PUCCH repetitions, as described above. 
     As further shown in  FIG. 8 , in some aspects, process  800  may include performing a channel estimation of an uplink channel associated with the one or more PUCCH repetitions by applying DMRS bundling among DMRSs of the one or more PUCCH repetitions (block  830 ). For example, the base station (e.g., using channel estimation component  1008 , depicted in  FIG. 10 ) may perform a channel estimation of an uplink channel associated with the one or more PUCCH repetitions by applying DMRS bundling among DMRSs of the one or more PUCCH repetitions, as described above. 
     Process  800  may include additional aspects, such as any single aspect or any combination of aspects described below and/or in connection with one or more other processes described elsewhere herein. 
     In a first aspect, performing the channel estimation of the uplink channel associated with the one or more PUCCH repetitions comprises aggregating the DMRSs of the one or more PUCCH repetitions, and performing the channel estimation of the uplink channel based at least in part on the aggregated DMRSs of the one or more PUCCH repetitions. 
     In a second aspect, alone or in combination with the first aspect, transmitting the indication that DMRS bundling is to be used for channel estimation by the base station comprises transmitting, to the one or more UEs, the semi-static configuration indicating that DMRS bundling is to be used for channel estimation by the base station for PUCCH repetitions. 
     In a third aspect, alone or in combination with the first aspect, transmitting the indication that DMRS bundling is to be used for channel estimation by the base station comprises transmitting, to the UE of the one or more UEs, the dynamic indication, wherein the dynamic indication is specific to the UE. 
     In a fourth aspect, alone or in combination with the first aspect, transmitting the indication that DMRS bundling is to be used for channel estimation by the base station comprises transmitting, to the one or more UEs, a group-common dynamic indication that DMRS bundling is to be used for channel estimation by the base station for PUCCH repetitions. 
     In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, transmitting the indication that DMRS bundling is to be used for channel estimation by the base station comprises transmitting the indication via a DCI message. 
     In a sixth aspect, alone or in combination with one or more of the first through fourth aspects, transmitting the indication that DMRS bundling is to be used for channel estimation by the base station comprises transmitting the indication via a MAC-CE message. 
     In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, transmitting the indication that DMRS bundling is to be used for channel estimation by the base station comprises transmitting, to the one or more UEs, an indication of a PUCCH repetition factor for one or more PUCCH repetitions and the indication that DMRS bundling is to be used for channel estimation by the base station for the one or more PUCCH repetitions. 
     In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, process  800  includes receiving, from the UE of the one or more UEs, a capability message indicating a phase continuity capability of the UE. 
     In a ninth aspect, alone or in combination with one or more of the first and fourth through eighth aspects, the indication that DMRS bundling is to be used for channel estimation by the base station is a group-common indication associated with a set of UEs, and process  800  includes identifying a subset of UEs, from the set of UEs, that have indicated a sufficient phase continuity capability for DMRS bundling, and performing channel estimation by applying DMRS bundling among DMRSs of PUCCH repetitions received from the subset of UEs. 
     In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, transmitting the indication that DMRS bundling is to be used for channel estimation by the base station comprises transmitting, to the one or more UEs, an indication of one or more PUCCH repetition groups and an indication that DMRS bundling is to be applied by the base station across DMRSs of each PUCCH repetition included in a PUCCH repetition group. 
     In an eleventh aspect, alone or in combination with the tenth aspect, performing the channel estimation of the uplink channel associated with the one or more PUCCH repetitions comprises identifying that the one or more PUCCH repetitions are included in a same PUCCH repetition group, and applying DMRS bundling among DMRSs of the one or more PUCCH repetitions for channel estimation based at least in part on identifying that the one or more PUCCH repetitions are included in the same PUCCH repetition group. 
     In a twelfth aspect, alone or in combination with one or more of the tenth through eleventh aspects, transmitting the indication of the one or more PUCCH repetition groups comprises transmitting an indication of a number of PUCCH repetitions to be included in each PUCCH repetition group. 
     In a thirteenth aspect, alone or in combination with one or more of the tenth through twelfth aspects, transmitting the indication of the one or more PUCCH repetition groups comprises transmitting an indication of a threshold amount of time between consecutive PUCCH repetitions, wherein consecutive PUCCH repetitions that have a time gap between the consecutive PUCCH repetitions that satisfies the threshold amount of time are to be included in a PUCCH repetition group. 
     In a fourteenth aspect, alone or in combination with one or more of the first through thirteenth aspects, receiving the one or more PUCCH repetitions comprises receiving, from the UE, a first PUCCH repetition included in a PUCCH repetition group, determining that a second PUCCH repetition included in the PUCCH repetition group is not transmitted by the UE, and receiving, from the UE, a third PUCCH repetition included in the PUCCH repetition group after determining that the second PUCCH repetition included in the PUCCH repetition group is not transmitted. 
     In a fifteenth aspect, alone or in combination with the fourteenth aspect, performing the channel estimation of the uplink channel associated with the one or more PUCCH repetitions comprises determining that DMRS bundling is not to be applied among DMRSs of the first PUCCH repetition and the third PUCCH repetition. 
     In a sixteenth aspect, alone or in combination with one or more of the fourteenth through fifteenth aspects, performing the channel estimation of the uplink channel associated with the one or more PUCCH repetitions comprises at least one of performing channel estimation by applying DMRS bundling among DMRSs of first PUCCH repetition and any PUCCH repetitions included in the PUCCH repetition group that are transmitted prior to determining that the second PUCCH repetition included in the PUCCH repetition group is not transmitted, or performing channel estimation by applying DMRS bundling among DMRSs of third PUCCH repetition and any PUCCH repetitions included in the PUCCH repetition group that are transmitted after determining that the second PUCCH repetition included in the PUCCH repetition group is not transmitted. 
     In a seventeenth aspect, alone or in combination with one or more of the first through sixteenth aspects, transmitting the indication that DMRS bundling is to be used for channel estimation by the base station comprises transmitting an indication that PUCCH repetitions that are to be transmitted by a UE using a same transmit beam are to be included in a PUCCH repetition group for DMRS bundling. 
     In an eighteenth aspect, alone or in combination with the seventeenth aspect, transmitting the indication that PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling comprises identifying whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling. 
     In a nineteenth aspect, alone or in combination with the eighteenth aspect, identifying whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling comprises determining whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group based at least in part on a phase continuity capability of the UE. 
     In a twentieth aspect, alone or in combination with the eighteenth aspect, identifying whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling comprises transmitting, to the UE, an indication of whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling. 
     Although  FIG. 8  shows example blocks of process  800 , in some aspects, process  800  may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in  FIG. 8 . Additionally, or alternatively, two or more of the blocks of process  800  may be performed in parallel. 
       FIG. 9  is a block diagram of an example apparatus  900  for wireless communication. The apparatus  900  may be a UE, or a UE may include the apparatus  900 . In some aspects, the apparatus  900  includes a reception component  902  and a transmission component  904 , which may be in communication with one another (for example, via one or more buses and/or one or more other components). As shown, the apparatus  900  may communicate with another apparatus  906  (such as a UE, a base station, or another wireless communication device) using the reception component  902  and the transmission component  904 . As further shown, the apparatus  900  may include a determination component  908 , among other examples. 
     In some aspects, the apparatus  900  may be configured to perform one or more operations described herein in connection with  FIGS. 4-6 . Additionally, or alternatively, the apparatus  900  may be configured to perform one or more processes described herein, such as process  700  of  FIG. 7 , or a combination thereof. In some aspects, the apparatus  900  and/or one or more components shown in  FIG. 9  may include one or more components of the UE described above in connection with  FIG. 2 . Additionally, or alternatively, one or more components shown in  FIG. 9  may be implemented within one or more components 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  902  may receive communications, such as reference signals, control information, data communications, or a combination thereof, from the apparatus  906 . The reception component  902  may provide received communications to one or more other components of the apparatus  900 . In some aspects, the reception component  902  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 of the apparatus  906 . In some aspects, the reception component  902  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  904  may transmit communications, such as reference signals, control information, data communications, or a combination thereof, to the apparatus  906 . In some aspects, one or more other components of the apparatus  906  may generate communications and may provide the generated communications to the transmission component  904  for transmission to the apparatus  906 . In some aspects, the transmission component  904  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  906 . In some aspects, the transmission component  904  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  904  may be co-located with the reception component  902  in a transceiver. 
     The reception component  902  may receive, from a base station, an indication that DMRS bundling is to be used for channel estimation by the base station for one or more PUCCH repetitions, where the indication is a semi-static configuration or a dynamic indication. The transmission component  904  may transmit, to the base station, the one or more PUCCH repetitions by maintaining a phase continuity among DMRSs of the one or more PUCCH repetitions based at least in part on receiving the indication that DMRS bundling is to be used. 
     The transmission component  904  may transmit, to the base station, a capability message indicating a phase continuity capability of the UE. 
     The determination component  908  may identify whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling based at least in part on a phase continuity capability of the UE. 
     The reception component  902  may receive, from the base station, an indication of whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling. 
     The transmission component  904  may apply one or more restrictions based at least in part on receiving the indication that DMRS bundling is to be used. 
     The number and arrangement of components shown in  FIG. 9  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. 9 . Furthermore, two or more components shown in  FIG. 9  may be implemented within a single component, or a single component shown in  FIG. 9  may be implemented as multiple, distributed components. Additionally, or alternatively, a set of (one or more) components shown in  FIG. 9  may perform one or more functions described as being performed by another set of components shown in  FIG. 9 . 
       FIG. 10  is a block diagram of an example apparatus  1000  for wireless communication. The apparatus  1000  may be a base station, or a base station may include the apparatus  1000 . In some aspects, the apparatus  1000  includes a reception component  1002  and a transmission component  1004 , which may be in communication with one another (for example, via one or more buses and/or one or more other components). As shown, the apparatus  1000  may communicate with another apparatus  1006  (such as a UE, a base station, or another wireless communication device) using the reception component  1002  and the transmission component  1004 . As further shown, the apparatus  1000  may include a channel estimation component  1008 , among other examples. 
     In some aspects, the apparatus  1000  may be configured to perform one or more operations described herein in connection with  FIGS. 4-6 . Additionally, or alternatively, the apparatus  1000  may be configured to perform one or more processes described herein, such as process  800  of  FIG. 8 , or a combination thereof. In some aspects, the apparatus  1000  and/or one or more components shown in  FIG. 10  may include one or more components of the base station described above in connection with  FIG. 2 . Additionally, or alternatively, one or more components shown in  FIG. 10  may be implemented within one or more components 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  1002  may receive communications, such as reference signals, control information, data communications, or a combination thereof, from the apparatus  1006 . The reception component  1002  may provide received communications to one or more other components of the apparatus  1000 . In some aspects, the reception component  1002  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 of the apparatus  1006 . In some aspects, the reception component  1002  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  1004  may transmit communications, such as reference signals, control information, data communications, or a combination thereof, to the apparatus  1006 . In some aspects, one or more other components of the apparatus  1006  may generate communications and may provide the generated communications to the transmission component  1004  for transmission to the apparatus  1006 . In some aspects, the transmission component  1004  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  1006 . In some aspects, the transmission component  1004  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  1004  may be co-located with the reception component  1002  in a transceiver. 
     The transmission component  1004  may transmit, to one or more UEs, an indication that DMRS bundling is to be used for channel estimation by the base station for PUCCH repetitions. The reception component  1002  may receive, from a UE of the one or more UEs, one or more PUCCH repetitions. The channel estimation component  1008  may perform a channel estimation of an uplink channel associated with the one or more PUCCH repetitions by applying DMRS bundling among DMRSs of the one or more PUCCH repetitions. 
     The reception component  1002  may receive, from the UE of the one or more UEs, a capability message indicating a phase continuity capability of the UE. 
     The number and arrangement of components shown in  FIG. 10  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. 10 . Furthermore, two or more components shown in  FIG. 10  may be implemented within a single component, or a single component shown in  FIG. 10  may be implemented as multiple, distributed components. Additionally, or alternatively, a set of (one or more) components shown in  FIG. 10  may perform one or more functions described as being performed by another set of components shown in  FIG. 10 . 
     The following provides an overview of some aspects of the present disclosure: 
     Aspect 1: A method of wireless communication performed by a user equipment (UE), comprising: receiving, from a base station, an indication that demodulation reference signal (DMRS) bundling is to be used for channel estimation by the base station for one or more physical uplink control channel (PUCCH) repetitions, wherein the indication is a semi-static configuration or a dynamic indication; and transmitting, to the base station, the one or more PUCCH repetitions by maintaining a phase continuity among DMRSs of the one or more PUCCH repetitions based at least in part on receiving the indication that DMRS bundling is to be used. 
     Aspect 2: The method of Aspect 1, wherein receiving the indication that DMRS bundling is to be used for channel estimation by the base station comprises: receiving, from the base station, the semi-static configuration indicating that DMRS bundling is to be used for channel estimation by the base station for the one or more PUCCH repetitions. 
     Aspect 3: The method of Aspect 1, wherein receiving the indication that DMRS bundling is to be used for channel estimation by the base station comprises: receiving the dynamic indication, wherein the dynamic indication is specific to the UE. 
     Aspect 4: The method of Aspect 1, wherein receiving the indication that DMRS bundling is to be used for channel estimation by the base station comprises: receiving, from the base station, a group-common dynamic indication that DMRS bundling is to be used for channel estimation by the base station for the one or more PUCCH repetitions. 
     Aspect 5: The method of any of Aspects 1 and 3-4, wherein receiving the indication that DMRS bundling is to be used for channel estimation by the base station comprises receiving the indication via a downlink control information (DCI) message. 
     Aspect 6: The method of any of Aspects 1 and 3-4, wherein receiving the indication that DMRS bundling is to be used for channel estimation by the base station comprises receiving the indication via a medium access control (MAC) control element (MAC-CE) message. 
     Aspect 7: The method of any of Aspects 1-6, wherein receiving the indication that DMRS bundling is to be used for channel estimation by the base station comprises: receiving, from the base station, an indication of a PUCCH repetition factor for the one or more PUCCH repetitions and the indication that DMRS bundling is to be used for channel estimation by the base station for the one or more PUCCH repetitions. 
     Aspect 8: The method of any of Aspects 1-7, further comprising: transmitting, to the base station, a capability message indicating a phase continuity capability of the UE. 
     Aspect 9: The method of any of Aspects 1 and 4-8, wherein the indication that DMRS bundling is to be used for channel estimation by the base station is a group-common indication associated with a set of UEs, that includes the UE, and the base station applies DMRS bundling to PUCCH repetitions transmitted by a subset of UEs, from the set of UEs, that have a sufficient phase continuity capability. 
     Aspect 10: The method of any of Aspects 1-9, wherein receiving the indication that DMRS bundling is to be used for channel estimation by the base station comprises: receiving, from the base station, an indication of a PUCCH repetition group and an indication that DMRS bundling is to be applied by the base station across DMRSs of each PUCCH repetition included in the PUCCH repetition group. 
     Aspect 11: The method of Aspect 10, wherein receiving the indication of the PUCCH repetition group comprises: receiving an indication of a number of PUCCH repetitions to be included in each PUCCH repetition group. 
     Aspect 12: The method of any of Aspects 10-11, wherein receiving the indication of the PUCCH repetition group comprises: receiving an indication of a threshold amount of time between consecutive PUCCH repetitions, wherein consecutive PUCCH repetitions that have a time gap between the consecutive PUCCH repetitions that satisfies the threshold amount of time are to be included in a PUCCH repetition group. 
     Aspect 13: The method of any of Aspects 1-12, wherein transmitting the one or more PUCCH repetitions comprises: transmitting a first PUCCH repetition included in a PUCCH repetition group; determining that a second PUCCH repetition included in the PUCCH repetition group is not to be transmitted; and transmitting a third PUCCH repetition included in the PUCCH repetition group after determining that the second PUCCH repetition included in the PUCCH repetition group is not to be transmitted, wherein DMRS bundling is not to be applied by the base station among DMRSs of the first PUCCH repetition and the third PUCCH repetition. 
     Aspect 14: The method of Aspect 13, wherein DMRS bundling is to be applied by the base station among DMRSs of the first PUCCH repetition and any PUCCH repetitions included in the PUCCH repetition group that are transmitted prior to determining that the second PUCCH repetition included in the PUCCH repetition group is not to be transmitted. 
     Aspect 15: The method of any of Aspects 1-14, wherein receiving the indication that DMRS bundling is to be used for channel estimation by the base station comprises: receiving an indication that PUCCH repetitions that are to be transmitted by the UE using a same transmit beam are to be included in a PUCCH repetition group for DMRS bundling. 
     Aspect 16: The method of Aspect 15, wherein receiving the indication that PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling comprises: identifying that consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling. 
     Aspect 17: The method of Aspect 15, wherein receiving the indication that PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling comprises: identifying that consecutive PUCCH repetitions and non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling. 
     Aspect 18: The method of any of Aspects 15-17, further comprising: identifying whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling based at least in part on a phase continuity capability of the UE. 
     Aspect 19: The method of any of Aspects 15-17, further comprising: receiving, from the base station, an indication of whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling. 
     Aspect 20: The method of any of Aspects 1-19, wherein transmitting the one or more PUCCH repetitions comprises applying one or more restrictions based at least in part on receiving the indication that DMRS bundling is to be used. 
     Aspect 21: The method of Aspect 20, wherein the one or more restrictions include at least one of: refraining from transmitting another uplink signal between repetitions of the one or more PUCCH repetitions, maintaining the phase continuity among the DMRSs of the one or more PUCCH repetitions, or using a beam pattern or precoder pattern when transmitting the one or more PUCCH repetitions. 
     Aspect 22: A method of wireless communication performed by a base station, comprising: transmitting, to one or more user equipment (UEs), an indication that demodulation reference signal (DMRS) bundling is to be used for channel estimation by the base station for physical uplink control channel (PUCCH) repetitions; receiving, from a UE of the one or more UEs, one or more PUCCH repetitions; and performing a channel estimation of an uplink channel associated with the one or more PUCCH repetitions by applying DMRS bundling among DMRSs of the one or more PUCCH repetitions. 
     Aspect 23: The method of Aspect 22, wherein performing the channel estimation of the uplink channel associated with the one or more PUCCH repetitions comprises: aggregating the DMRSs of the one or more PUCCH repetitions; and performing the channel estimation of the uplink channel based at least in part on the aggregated DMRSs of the one or more PUCCH repetitions. 
     Aspect 24: The method of any of Aspects 22-23, wherein transmitting the indication that DMRS bundling is to be used for channel estimation by the base station comprises: transmitting, to the one or more UEs, a semi-static configuration indicating that DMRS bundling is to be used for channel estimation by the base station for PUCCH repetitions. 
     Aspect 25: The method of any of Aspects 22-23, wherein transmitting the indication that DMRS bundling is to be used for channel estimation by the base station comprises: transmitting, to the UE of the one or more UEs, a dynamic indication that is specific to the UE. 
     Aspect 26: The method of any of Aspects 22-23, wherein transmitting the indication that DMRS bundling is to be used for channel estimation by the base station comprises: transmitting, to the one or more UEs, a group-common dynamic indication that DMRS bundling is to be used for channel estimation by the base station for PUCCH repetitions. 
     Aspect 27: The method of any of Aspects 22-23 and 25-26, wherein transmitting the indication that DMRS bundling is to be used for channel estimation by the base station comprises transmitting the indication via a downlink control information (DCI) message. 
     Aspect 28: The method of any of Aspects 22-23 and 25-26, wherein transmitting the indication that DMRS bundling is to be used for channel estimation by the base station comprises transmitting the indication via a medium access control (MAC) control element (MAC-CE) message. 
     Aspect 29: The method of any of Aspects 22-28, wherein transmitting the indication that DMRS bundling is to be used for channel estimation by the base station comprises: transmitting, to the one or more UEs, an indication of a PUCCH repetition factor for one or more PUCCH repetitions and the indication that DMRS bundling is to be used for channel estimation by the base station for the one or more PUCCH repetitions. 
     Aspect 30: The method of any of Aspects 22-29, further comprising: receiving, from the UE of the one or more UEs, a capability message indicating a phase continuity capability of the UE. 
     Aspect 31: The method of any of Aspects 22-23 and 26-30, wherein the indication that DMRS bundling is to be used for channel estimation by the base station is a group-common indication associated with a set of UEs, the method further comprising: identifying a subset of UEs, from the set of UEs, that have indicated a sufficient phase continuity capability for DMRS bundling; and performing channel estimation by applying DMRS bundling among DMRSs of PUCCH repetitions received from the subset of UEs. 
     Aspect 32: The method of any of Aspects 22-31, wherein transmitting the indication that DMRS bundling is to be used for channel estimation by the base station comprises: transmitting, to the one or more UEs, an indication of one or more PUCCH repetition groups and an indication that DMRS bundling is to be applied by the base station across DMRSs of each PUCCH repetition included in a PUCCH repetition group. 
     Aspect 33: The method of Aspect 32, wherein performing the channel estimation of the uplink channel associated with the one or more PUCCH repetitions comprises: identifying that the one or more PUCCH repetitions are included in a same PUCCH repetition group; and applying DMRS bundling among DMRSs of the one or more PUCCH repetitions for channel estimation based at least in part on identifying that the one or more PUCCH repetitions are included in the same PUCCH repetition group. 
     Aspect 34: The method of any of Aspects 32-33, wherein transmitting the indication of the one or more PUCCH repetition groups comprises: transmitting an indication of a number of PUCCH repetitions to be included in each PUCCH repetition group. 
     Aspect 35: The method of any of Aspects 32-34, wherein transmitting the indication of the one or more PUCCH repetition groups comprises: transmitting an indication of a threshold amount of time between consecutive PUCCH repetitions, wherein consecutive PUCCH repetitions that have a time gap between the consecutive PUCCH repetitions that satisfies the threshold amount of time are to be included in a PUCCH repetition group. 
     Aspect 36: The method of any of Aspects 22-35, wherein receiving the one or more PUCCH repetitions comprises: receiving, from the UE, a first PUCCH repetition included in a PUCCH repetition group; determining that a second PUCCH repetition included in the PUCCH repetition group is not transmitted by the UE; and receiving, from the UE, a third PUCCH repetition included in the PUCCH repetition group after determining that the second PUCCH repetition included in the PUCCH repetition group is not transmitted. 
     Aspect 37: The method of Aspect 36, wherein performing the channel estimation of the uplink channel associated with the one or more PUCCH repetitions comprises: determining that DMRS bundling is not to be applied among DMRSs of the first PUCCH repetition and the third PUCCH repetition. 
     Aspect 38: The method of any of Aspects 36-37, wherein performing the channel estimation of the uplink channel associated with the one or more PUCCH repetitions comprises at least one of: performing channel estimation by applying DMRS bundling among DMRSs of first PUCCH repetition and any PUCCH repetitions included in the PUCCH repetition group that are transmitted prior to determining that the second PUCCH repetition included in the PUCCH repetition group is not transmitted; or performing channel estimation by applying DMRS bundling among DMRSs of third PUCCH repetition and any PUCCH repetitions included in the PUCCH repetition group that are transmitted after determining that the second PUCCH repetition included in the PUCCH repetition group is not transmitted. 
     Aspect 39: The method of any of Aspects 22-38, wherein transmitting the indication that DMRS bundling is to be used for channel estimation by the base station comprises: transmitting an indication that PUCCH repetitions that are to be transmitted by a UE using a same transmit beam are to be included in a PUCCH repetition group for DMRS bundling. 
     Aspect 40: The method of Aspect 39, wherein transmitting the indication that PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling comprises: identifying whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling. 
     Aspect 41: The method of Aspect 40, wherein identifying whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling comprises: determining whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group based at least in part on a phase continuity capability of the UE. 
     Aspect 42: The method of Aspect 40, wherein identifying whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling comprises: transmitting, to the UE, an indication of whether non-consecutive PUCCH repetitions that are to be transmitted by the UE using the same transmit beam are to be included in the PUCCH repetition group for DMRS bundling. 
     Aspect 43: 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 of Aspects 1-21. 
     Aspect 44: 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 of Aspects 1-21. 
     Aspect 45: An apparatus for wireless communication, comprising at least one means for performing the method of one or more of Aspects 1-21. 
     Aspect 46: 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 of Aspects 1-21. 
     Aspect 47: 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 of Aspects 1-21. 
     Aspect 48: 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 of Aspects 22-42. 
     Aspect 49: 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 of Aspects 22-42. 
     Aspect 50: An apparatus for wireless communication, comprising at least one means for performing the method of one or more of Aspects 22-42. 
     Aspect 51: 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 of Aspects 22-42. 
     Aspect 52: 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 of Aspects 22-42. 
     The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the precise forms 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 and/or a combination of hardware and software. “Software” shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, and/or functions, among other examples, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. As used herein, a processor is implemented in hardware and/or a combination of hardware and software. It will be apparent that systems and/or methods described herein may be implemented in different forms of hardware and/or a combination of hardware and software. The actual specialized control hardware or software code used to implement these systems and/or methods is not limiting of the aspects. Thus, the operation and behavior of the systems and/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 and/or methods based, at least in part, on the description herein. 
     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, not equal to the threshold, or the like. 
     Even though particular combinations of features are recited in the claims and/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 and/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, a phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination with multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering of a, b, and c). 
     No element, act, or instruction used herein should 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.” Further, as used herein, the article “the” is intended to include one or more items referenced in connection with the article “the” and may be used interchangeably with “the one or more.” Furthermore, as used herein, the terms “set” and “group” are intended to include one or more items (e.g., 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,” “having,” or the like 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. Also, as used herein, the term “or” is intended to be inclusive when used in a series and may be used interchangeably with “and/or,” unless explicitly stated otherwise (e.g., if used in combination with “either” or “only one of”).