Patent Publication Number: US-2022225146-A1

Title: Techniques for demodulation reference signal based signal-to-noise ratio for demodulation processing

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This patent application claims priority to U.S. Provisional Patent Application No. 63/136,932, filed on Jan. 13, 2021, entitled “TECHNIQUES FOR DEMODULATION REFERENCE SIGNAL BASED SIGNAL-TO-NOISE RATIO FOR DEMODULATION PROCESSING,” and assigned to the assignee hereof. This patent application also claims priority to U.S. Provisional Patent Application No. 63/172,827, filed on Apr. 9, 2021, entitled “TECHNIQUES FOR DEMODULATION REFERENCE SIGNAL BASED SIGNAL-TO-NOISE RATIO FOR DEMODULATION PROCESSING,” and assigned to the assignee hereof. The disclosures of the prior applications are considered part of and are 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) based signal-to-noise ratio (SNR) for demodulation processing. 
     DESCRIPTION OF RELATED ART 
     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. The downlink (or forward link) refers to the communication link from the BS to the UE, and the 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 measuring a first energy level of a demodulation reference signal (DMRS); measuring a second energy level of at least one of a tracking reference signal (TRS) or a synchronization signal block (SSB); determining, based at least in part on the first energy level and the second energy level, a DMRS signal-to-noise ratio (SNR); performing, based at least in part on the DMRS SNR, channel estimation for a physical channel associated with a communication to determine an estimated channel; and performing, based at least in part on the estimated channel, demodulation processing for the communication. 
     In some aspects, a UE for wireless communication includes a memory and one or more processors coupled to the memory, the one or more processors configured to: measure a first energy level of a DMRS; measure a second energy level of at least one of a TRS or an SSB; determine, based at least in part on the first energy level and the second energy level, a DMRS SNR; perform, based at least in part on the DMRS SNR, channel estimation for a physical channel associated with a communication to determine an estimated channel; and perform, based at least in part on the estimated channel, demodulation processing for the communication. 
     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: measure a first energy level of a DMRS; measure a second energy level of at least one of a TRS or an SSB; determine, based at least in part on the first energy level and the second energy level, a DMRS SNR; perform, based at least in part on the DMRS SNR, channel estimation for a physical channel associated with a communication to determine an estimated channel; and perform, based at least in part on the estimated channel, demodulation processing for the communication. 
     In some aspects, an apparatus for wireless communication includes means for measuring a first energy level of a DMRS; means for measuring a second energy level of at least one of a TRS or an SSB; means for determining, based at least in part on the first energy level and the second energy level, a DMRS SNR; means for performing, based at least in part on the DMRS SNR, channel estimation for a physical channel associated with a communication to determine an estimated channel; and means for performing, based at least in part on the estimated channel, demodulation processing for the communication. 
     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. 
    
    
     
       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 physical channels and reference signals in a wireless network, in accordance with the present disclosure. 
         FIGS. 4 and 5  are diagrams illustrating examples associated with demodulation reference signal (DMRS) based signal-to-noise ratio (SNR) for demodulation processing, in accordance with the present disclosure. 
         FIG. 6  is a diagram illustrating an example process associated with DMRS based SNR for demodulation processing, in accordance with the present disclosure. 
         FIGS. 7 and 8  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, e.g., 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. 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 T modulators (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, an/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. 
     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. 
     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 DMRS-based signal-to-noise ratio (SNR) for demodulation processing, 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  600  of  FIG. 6 , 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  600  of  FIG. 6 , 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. 
     In some aspects, the UE  120  includes means for measuring a first energy level of a DMRS; means for measuring a second energy level of at least one of a tracking reference signal (TRS) or a synchronization signal block (SSB); means for determining, based at least in part on the first energy level and the second energy level, a DMRS SNR; means for performing, based at least in part on the DMRS SNR, channel estimation for a physical channel associated with a communication to determine an estimated channel; and/or means for performing, based at least in part on the estimated channel, demodulation processing for the communication. 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, using a beam that is selected based at least in part on at least one of the TRS or the SSB, the communication on the physical channel. 
     In some aspects, the UE  120  includes means for measuring a reference signal SNR (RS-SNR) that is based at least in part on the second energy level. 
     In some aspects, the UE  120  includes means for determining the DMRS SNR for at least one of: a slot during which the communication is received, an antenna port used for receiving the communication, or a DMRS port associated with the DMRS. 
     In some aspects, the UE  120  includes means for measuring the DMRS SNR based at least in part on at least one of: the first energy level, the second energy level, a noise level associated with the DMRS, or a RS-SNR that is based at least in part on the second energy level. 
     In some aspects, the UE  120  includes means for measuring a noise level associated with the DMRS; and/or means for determining, based at least in part on the first energy level and the noise level, the DMRS SNR. 
     In some aspects, the UE  120  includes means for determining, based at least in part on the first energy level and the second energy level, a value; means for measuring an RS-SNR that is based at least in part on the second energy level; and/or means for modifying the RS-SNR by the value to obtain the DMRS SNR. 
     In some aspects, the UE  120  includes means for determining the value based at least in part on a function of the first energy level and the second energy level. 
     In some aspects, the UE  120  includes means for determining, based at least in part on the first energy level and a measured noise level associated with the DMRS, a first SNR; means for modifying an RS-SNR, that is based at least in part on the second energy level, by a first value to obtain a second SNR; means for determining whether a ratio, of the first SNR to the second SNR, satisfies a threshold; and/or means for determining that the DMRS SNR is the first SNR if the ratio of the first SNR to the second SNR satisfies the threshold, or the second SNR if the ratio of the first SNR to the second SNR does not satisfy the threshold. 
     In some aspects, the UE  120  includes means for determining, based at least in part on the first energy level and a measured noise level associated with the DMRS, a first SNR; means for modifying an RS-SNR, that is based at least in part on the second energy level, by a first value to obtain a second SNR; means for modifying the second SNR by a second value to obtain a third SNR; and/or means for determining that the DMRS SNR is the first SNR if the first SNR is greater than the third SNR, or the second SNR if the first SNR is less than or equal to the third SNR. 
     In some aspects, the UE  120  includes means for performing a delay spread estimation for the channel based at least in part on the DMRS SNR. In some aspects, the UE  120  includes means for measuring an RS-SNR that is based at least in part on the second energy level; means for comparing the RS-SNR to the DMRS SNR to obtain a difference between the RS-SNR and the DMRS SNR; and/or means for performing the delay spread estimation for the channel using the DMRS SNR based at least in part on the difference between the RS-SNR and the DMRS SNR satisfying a collision threshold. 
     In some aspects, the UE  120  includes means for performing, if the RS-SNR satisfies a reliability threshold, the delay spread estimation for the channel using the DMRS SNR to set a threshold value for separating a signal of the channel from noise over the estimated delay spread of the channel. In some aspects, the UE  120  includes means for determining, if the RS-SNR does not satisfy a reliability threshold, that the delay spread for the channel is a default value. 
     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 physical channels and reference signals in a wireless network, in accordance with the present disclosure. As shown in  FIG. 3 , downlink channels and downlink reference signals may carry information from a base station  110  to a UE  120 , and uplink channels and uplink reference signals may carry information from a UE  120  to a base station  110 . 
     As shown, a downlink channel may include a physical downlink control channel (PDCCH) that carries downlink control information (DCI), a physical downlink shared channel (PDSCH) that carries downlink data, or a physical broadcast channel (PBCH) that carries system information, among other examples. In some aspects, PDSCH communications may be scheduled by PDCCH communications. As further shown, an uplink channel may include a physical uplink control channel (PUCCH) that carries uplink control information (UCI), a physical uplink shared channel (PUSCH) that carries uplink data, or a physical random access channel (PRACH) used for initial network access, among other examples. In some aspects, the UE  120  may transmit acknowledgement (ACK) or negative acknowledgement (NACK) feedback (e.g., ACK/NACK feedback or ACK/NACK information) in UCI on the PUCCH and/or the PUSCH. 
     As further shown, a downlink reference signal may include an SSB, a channel state information (CSI) reference signal (CSI-RS), a DMRS, a positioning reference signal (PRS), a phase tracking reference signal (PTRS), and/or a TRS, among other examples. As also shown, an uplink reference signal may include a sounding reference signal (SRS), a DMRS, and/or a PTRS, among other examples. 
     An SSB may carry information used for initial network acquisition and synchronization, such as a PSS, an SSS, a PBCH, and a PBCH DMRS. An SSB is sometimes referred to as a synchronization signal/PBCH (SS/PBCH) block. In some aspects, the base station  110  may transmit multiple SSBs on multiple corresponding beams, and the SSBs may be used for beam selection. 
     A CSI-RS may carry information used for downlink channel estimation (e.g., downlink CSI acquisition), which may be used for scheduling, link adaptation, or beam management, among other examples. The base station  110  may configure a set of CSI-RSs for the UE  120 , and the UE  120  may measure the configured set of CSI-RSs. Based at least in part on the measurements, the UE  120  may perform channel estimation and may report channel estimation parameters to the base station  110  (e.g., in a CSI report), such as a CQI, a precoding matrix indicator (PMI), a CSI-RS resource indicator (CRI), a layer indicator (LI), a rank indicator (RI), or an RSRP, among other examples. The base station  110  may use the CSI report to select transmission parameters for downlink communications to the UE  120 , such as a number of transmission layers (e.g., a rank), a precoding matrix (e.g., a precoder), an MCS, or a refined downlink beam (e.g., using a beam refinement procedure or a beam management procedure), among other examples. 
     A DMRS may carry information used to estimate a radio channel for demodulation of an associated physical channel (e.g., PDCCH, PDSCH, PBCH, PUCCH, or PUSCH). 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. As shown, DMRSs are used for both downlink communications and uplink communications. 
     A PTRS may carry information used to compensate for oscillator phase noise. Typically, the phase noise increases as the oscillator carrier frequency increases. Thus, PTRS can be utilized at high carrier frequencies, such as millimeter wave frequencies, to mitigate phase noise. The PTRS may be used to track the phase of the local oscillator and to enable suppression of phase noise and common phase error (CPE). As shown, PTRSs are used for both downlink communications (e.g., on the PDSCH) and uplink communications (e.g., on the PUSCH). 
     A TRS may carry information used to assist in time domain and frequency domain tracking. The TRS may be used to track transmission path delay spread and/or Doppler spread. A TRS may be UE-specific. In some aspects, a TRS may be transmitted in a TRS burst. A TRS burst may consist of four OFDM symbols in two consecutive slots. In some aspects, a TRS may be associated with one or more CSI-RS configurations. For example, a TRS burst may use one or more CSI-RS resources. 
     A PRS may carry information used to enable timing or ranging measurements of the UE  120  based on signals transmitted by the base station  110  to improve observed time difference of arrival (OTDOA) positioning performance. For example, a PRS may be a pseudo-random Quadrature Phase Shift Keying (QPSK) sequence mapped in diagonal patterns with shifts in frequency and time to avoid collision with cell-specific reference signals and control channels (e.g., a PDCCH). In general, a PRS may be designed to improve detectability by the UE  120 , which may need to detect downlink signals from multiple neighboring base stations in order to perform OTDOA-based positioning. Accordingly, the UE  120  may receive a PRS from multiple cells (e.g., a reference cell and one or more neighbor cells), and may report a reference signal time difference (RSTD) based on OTDOA measurements associated with the PRSs received from the multiple cells. In some aspects, the base station  110  may then calculate a position of the UE  120  based on the RSTD measurements reported by the UE  120 . 
     An SRS may carry information used for uplink channel estimation, which may be used for scheduling, link adaptation, precoder selection, or beam management, among other examples. The base station  110  may configure one or more SRS resource sets for the UE  120 , and the UE  120  may transmit SRSs on the configured SRS resource sets. An SRS resource set may have a configured usage, such as uplink CSI acquisition, downlink CSI acquisition for reciprocity-based operations, uplink beam management, among other examples. The base station  110  may measure the SRSs, may perform channel estimation based at least in part on the measurements, and may use the SRS measurements to configure communications with the UE  120 . 
     As indicated above,  FIG. 3  is provided as an example. Other examples may differ from what is described with regard to  FIG. 3 . 
     In some cases, for performing demodulation processing of a signal, SNR information for a physical channel associated with the signal may be required. For example, a UE may obtain an SNR to be used for channel estimation of the physical channel (e.g., to determine an estimated channel). The UE may use the estimated channel to perform demodulation processing of the signal to obtain data carried by the signal. 
     In some wireless communication systems, such as millimeter wave systems (and/or for wireless communication devices operating in FR2 or other frequency ranges), a UE may measure an SNR, for channel estimation to facilitate demodulation processing of a signal, using a TRS or an SSB. An SNR that is measured using a TRS or an SSB may be referred to herein as an RS-SNR. However, in some cases, a measured RS-SNR may provide an inaccurate estimation of a demodulation SNR (e.g., an SNR for the physical channel and/or for a channel for a DMRS). For example, the physical channel and/or the channel for the DMRS may experience a beamforming gain that is greater than a beamforming gain experienced by the TRS or the SSB (e.g., resulting in the RS-SNR providing an inaccurate estimation of a demodulation SNR). Because the signals (e.g., the DMRS, the TRS, and/or the SSB) may be beamformed signals, an energy level of the signals may vary depending on a beamforming gain experienced by the signals. As a result, an RS-SNR that is based on the TRS and/or the SSB may be different than the SNR of the DMRS (e.g., the DMRS channel) and/or the physical channel. 
     In some cases, a combination of a precoder and a beam used at a TRS port or an SSB port may introduce an imbalance (e.g., a difference) between the RS-SNR and the SNR of the DMRS. For example, the UE and a base station may select a beam (or a beam pair) for communications based at least in part on a measured beam parameter (e.g., RSRP and/or SNR) of the beam. The beam parameter may be measured using the TRS and/or the SSB and may indicate an average beam parameter across multiple antenna ports (e.g., of the UE). The UE and/or the base station may select a beam with a best beam parameter for communications. However, in some cases, the selected beam may cause an imbalance between the RS-SNR (e.g., measured at a TRS port or an SSB port) and the SNR of the DMRS due to different channel conditions across antenna ports of the UE. For example, due to a movement or change in orientation of the UE (and/or of an antenna of the UE), the selected beam may cause an RS-SNR (e.g., measured by the UE at a TRS port or an SSB port) to provide an inaccurate estimation of a demodulation SNR for a physical channel and/or a DMRS channel. 
     In some cases, a TRS or an SSB may experience a collision with another signal, causing interference for the TRS or the SSB. As a result, the interference experienced by the TRS or the SSB may be different than interference experienced by the physical channel and/or the DMRS channel. For example, neighboring cells may configure TRSs and/or SSBs to use the same or similar frequencies. Therefore, the TRS or the SSB may collide with a TRS or an SSB transmitted from a neighboring cell, resulting in interference that may not be experience by the physical channel and/or the DMRS channel. Therefore, an RS-SNR measured by the UE may provide inaccurate estimation of a demodulation SNR for a physical channel and/or a DMRS channel. By using an RS-SNR that provides an inaccurate estimation of a demodulation SNR for a physical channel and/or a DMRS channel, the UE may perform an inaccurate channel estimation (e.g., resulting in an inaccurate estimated channel). Using an inaccurate estimated channel for demodulation processing results in decreased demodulation performance. As a result, the UE may experience throughput degradation and/or a decreased spectral efficiency for signals that are demodulated using the inaccurate estimated channel. 
     Some techniques and apparatuses described herein enable DMRS based SNR for demodulation processing. For example, a UE may measure an SNR of a received DMRS (e.g., based at least in part on an energy level of the DMRS and a noise level of the DMRS). The UE may use the SNR of the DMRS to perform channel estimation of a physical channel (e.g., to obtain an estimated channel). The UE may perform demodulation processing of a signal based at least in part on the estimated channel. By using an SNR that is measured directly from a DMRS, a UE may ensure that the SNR used for channel estimation to facilitate demodulation processing is an accurate estimation of the SNR experienced by the physical channel and/or the DMRS channel. 
     In some cases, an SNR measured directly from a DMRS (e.g., only from a DMRS) may provide an unreliable measurement. For example, as a DMRS may be confined in a scheduled resource (e.g., rather than transmitted on a wideband) and/or transmitted only when necessary, the SNR measured directly from a DMRS may not be accurate due to a lack of filtering. Therefore, in some cases, the UE may determine a DMRS SNR (e.g., an SNR to be used for channel estimation to facilitate demodulation processing) based at least in part on an energy level of the DMRS and an energy level of a TRS and/or SSB. For example, the UE may measure an RS-SNR (e.g., using a TRS or SSB) and a reference signal (RS) energy level (e.g., based at least in part on the TRS or SSB). The UE may determine the DMRS SNR based at least in part on the energy level of the DMRS and a noise level of the DMRS in a slot in which a signal is received and/or based at least in part on an RS-SNR and an RS energy level (e.g., of a TRS or an SSB). Therefore, in scenarios in which the SNR measured directly from a DMRS (e.g., only from a DMRS) may provide an unreliable measurement, the UE may use a modified or biased RS-SNR (e.g., that is based at least in part on a ratio of the energy level of the DMRS to the RS energy level) to account for the issues described above that result from using the unmodified RS-SNR. As a result, the UE may ensure that an accurate channel estimation is performed to facilitate demodulation processing. Using an accurate channel estimation improves demodulation performance, improves throughput experienced by the UE, and/or improves spectral efficiency experienced by the UE, among other examples. 
       FIG. 4  is a diagram illustrating an example  400  associated with DMRS based SNR for demodulation processing, in accordance with the present disclosure. As shown in  FIG. 4 , example  400  includes communication between UE  120  and a base station  110 . In some aspects, example  400  may include communication between a first wireless communication device (e.g., a UE  120 , a base station  110 , and/or a wireless node) and a second wireless communication device. In some aspects, the UE  120  and the base station  110  may be included in a wireless network, such as wireless network  100 . In some aspects, the wireless network may be a millimeter wave wireless network. For example, the UE  120  and the base station  110  may operate in a millimeter wave operating frequency (and/or in FR2). The UE  120  and the base station  110  may communicate via a wireless access link, which may include an uplink and a downlink. 
     As shown by reference number  405 , the UE  120  may receive, from the base station  110 , one or more signals. For example, the base station  110  may transmit a communication to the UE  120  (e.g., that is to be decoded and demodulated by the UE  120 ). The base station  110  may transmit one or more reference signals to the UE  120 . For example, the base station  110  may transmit one or more DMRSs to the UE  120 . Additionally, the base station  110  may transmit, to the UE  120 , one or more TRSs and/or one or more SSBs. 
     In some aspects, the UE  120  and the base station  110  may communicate using a beam that is selected based at least in part on a measurement of a beam parameter (e.g., RSRP or SNR). The UE  120  (or the base station  110 ) may measure a TRS and/or an SSB to identify a value of the beam parameter. The value of the beam parameter may be an average value across multiple (or all) antenna ports of the UE  120  (or the base station  110 ). The UE  120  (or the base station  110 ) may report beam parameter values for multiple beams. The UE  120  and/or the base station  110  may select a beam for communications based at least in part on the report of beam parameters (e.g., a beam with a best or highest beam parameter may be selected for communications between the UE  120  and the base station  110 ). 
     As described above, the UE  120  may perform demodulation processing of a signal using an estimated channel of a physical channel used to transmit the signal. For example, as described in more detail below, the UE  120  may perform minimized mean square error (MMSE) channel estimation to determine the estimated channel. SNR information for the physical channel may be needed as an input to perform the channel estimation (e.g., the MMSE channel estimation). As described in more detail below, the UE  120  may obtain the SNR information (e.g., an estimated SNR of the physical channel) based at least in part on a DMRS received by the UE  120 . 
     As shown by reference number  410 , the UE  120  may measure or identify an energy level of a DMRS received by the UE  120 . The energy level may be a measure of a signal level of the DMRS and a noise level associated with the DMRS (e.g., the energy level may be a total received energy level, of signal plus noise, of the DMRS). The energy level may be an average energy level across one or more taps or tones of the DMRS (e.g., based at least in part on the scheduled resources for the DMRS). In some aspects, the UE  120  may measure or identify the noise level of the DMRS. The UE  120  may measure or identify the energy level and/or the noise level of the DMRS using a port (e.g., a DMRS port) and a beam or channel associated with the DMRS. The UE  120  may measure or identify the energy level and/or the noise level of the DMRS for a slot (e.g., per slot) in which the DMRS or communication to be demodulated is received, for a receive antenna port of the UE  120  (e.g., per receive antenna port), and/or for a DMRS port used to receive the DMRS (e.g., per DMRS port). 
     As shown by reference number  415 , the UE  120  may measure or identify an energy level of at least one of a TRS or an SSB. The energy level of the reference signal (e.g., the TRS or the SSB) may be a measure of a signal level of the reference signal and a noise level associated with the reference signal (e.g., the energy level may be a total received energy level, of signal plus noise, of the reference signal). In some aspects, the UE  120  may measure or identify the noise level of the reference signal (e.g., the TRS or the SSB). In some aspects, the UE  120  may measure or identify an RS-SNR of the reference signal (e.g., the TRS or the SSB) based at least in part on the energy level of the reference signal and the noise level of the reference signal. The UE  120  may measure or identify the reference signal energy level and/or the noise level of the reference signal using a port (e.g., a TRS port or an SSB port) and a beam or channel associated with the reference signal. 
     As shown by reference number  420 , the UE  120  may determine a DMRS SNR (e.g., an SNR to be used by the UE  120  for channel estimation to facilitate demodulation processing) based at least in part on the energy level of the DMRS and/or the energy level of the reference signal (e.g., the TRS or the SSB). The UE  120  may determine the DMRS SNR based at least in part on the energy level of the DMRS, the energy level of the reference signal (e.g., the TRS or the SSB), a noise level of the DMRS, and/or the RS-SNR of the reference signal (e.g., the TRS or the SSB), among other examples. 
     In some aspects, the UE  120  may determine the DMRS SNR using only the energy level of the DMRS and the noise level of the DMRS. For example, the DMRS SNR may be determined according to the equation of 
     
       
         
           
             
               
                 
                   E 
                   ⁢ 
                   
                     E 
                     DMRS 
                   
                 
                 
                   N 
                   ⁢ 
                   
                     E 
                     DMRS 
                   
                 
               
               - 
               1 
             
             , 
           
         
       
     
     where EE DMRS  is the energy level of the DMRS and NE DMRS  is the noise level of the DMRS. By determining the DMRS SNR using only the energy level of the DMRS and the noise level of the DMRS, the UE  120  may be enabled to compensate for an imbalance in the energy level of the reference signal (e.g., of the TRS or SSB) compared to an energy level of the DMRS (e.g., of the DMRS channel). As a result, the UE  120  may be enabled to perform a more accurate channel estimation for a demodulation channel. 
     In some aspects, the UE  120  may determine the DMRS SNR based at least in part on modifying or scaling the RS-SNR of the reference signal (e.g., the TRS or the SSB). For example, the UE  120  may determine a value or a ratio based at least in part on the energy level of the DMRS and the energy level of the reference signal (e.g., the TRS or the SSB). For example, the value or the ratio may be determined based at least in part on a function of (e.g., a ratio of and/or a difference between) the energy level of the DMRS and the energy level of the reference signal (e.g., the TRS or the SSB). The value or the ratio may indicate a beamforming gain ratio between the DMRS and the reference signal (e.g., the TRS or the SSB). That is, the value or the ratio may indicate a received energy of the DMRS compared to a received energy of the reference signal (e.g., the TRS or the SSB). The UE  120  may determine the DMRS SNR by modifying or scaling the RS-SNR (e.g., of the TRS or SSB) by the value or the ratio. For example, the UE  120  may determine the DMRS SNR according to the equation 
     
       
         
           
             
               
                 
                   E 
                   ⁢ 
                   
                     E 
                     
                       D 
                       ⁢ 
                       M 
                       ⁢ 
                       R 
                       ⁢ 
                       S 
                     
                   
                 
                 
                   E 
                   ⁢ 
                   
                     E 
                     
                       R 
                       ⁢ 
                       S 
                     
                   
                 
               
               · 
               
                 SNR 
                 
                   R 
                   ⁢ 
                   S 
                 
               
             
             , 
           
         
       
     
     where EE DMRS  is the energy level of the DMRS, EE RS  is the energy level of the reference signal (e.g., the TRS or the SSB), and SNR RS  is the RS-SNR of the reference signal (e.g., the TRS or the SSB). In some aspects, the UE  120  may determine the DMRS SNR by further modifying or scaling the modified or scaled RS-SNR. For example, the UE  120  may determine the DMRS SNR according to the equation 
     
       
         
           
             
               
                 
                   E 
                   ⁢ 
                   
                     E 
                     
                       D 
                       ⁢ 
                       M 
                       ⁢ 
                       R 
                       ⁢ 
                       S 
                     
                   
                 
                 
                   E 
                   ⁢ 
                   
                     E 
                     
                       R 
                       ⁢ 
                       S 
                     
                   
                 
               
               · 
               
                 SNR 
                 
                   R 
                   ⁢ 
                   S 
                 
               
               · 
               N 
             
             , 
           
         
       
     
     where Nis a scaling value. By modifying or scaling the RS-SNR (e.g., of the TRS or SSB) by the value or the ratio, the UE  120  may be enabled to compensate for an imbalance in the energy level of the reference signal (e.g., of the TRS or SSB) compared to an energy level of the DMRS. As a result, the UE  120  may be enabled to perform a more accurate channel estimation for a demodulation channel. 
     In some aspects, the UE  120  may determine whether the DMRS SNR determined or computed using only the energy level of the DMRS and the noise level of the DMRS provides a sufficient reliability. For example, as described above, the DMRS may be confined to the scheduled resources. As a result, in some cases, the UE  120  may have insufficient resources to measure the energy level of the DMRS and the noise level of the DMRS to provide a reliable estimation for the DMRS SNR. In some aspects, the UE  120  may determine whether the DMRS SNR determined or computed using only the energy level of the DMRS and the noise level of the DMRS provides a sufficient reliability based at least in part on the energy level of the DMRS, the energy level of the reference signal (e.g., the TRS or the SSB), and/or the RS-SNR of the reference signal (e.g., the TRS or the SSB), among other examples. 
     For example, the UE  120  may use the modified or scaled RS-SNR (e.g., as described above) to determine whether to use the DMRS SNR determined or computed using only the energy level of the DMRS and the noise level of the DMRS. In some aspects, the UE  120  may determine whether a ratio of a first SNR (e.g., the DMRS SNR determined or computed using only the energy level of the DMRS and the noise level of the DMRS) to the modified or scaled RS-SNR (e.g., described above) satisfies (e.g., is greater than) a threshold. For example, the UE  120  may use the equation 
     
       
         
           
             
               
                 
                   ( 
                   
                     
                       
                         E 
                         ⁢ 
                         
                           E 
                           
                             D 
                             ⁢ 
                             M 
                             ⁢ 
                             R 
                             ⁢ 
                             S 
                           
                         
                       
                       
                         N 
                         ⁢ 
                         
                           E 
                           
                             D 
                             ⁢ 
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                             ⁢ 
                             R 
                             ⁢ 
                             S 
                           
                         
                       
                     
                     - 
                     1 
                   
                   ) 
                 
                 
                   
                     
                       EE 
                       
                         D 
                         ⁢ 
                         M 
                         ⁢ 
                         R 
                         ⁢ 
                         S 
                       
                     
                     
                       EE 
                       
                         R 
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                   · 
                   
                     SNR 
                     
                       R 
                       ⁢ 
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               &gt; 
               thershold 
             
             , 
                
             
               where 
               ⁢ 
                   
               
                 ( 
                 
                   
                     
                       E 
                       ⁢ 
                       
                         E 
                         
                           D 
                           ⁢ 
                           M 
                           ⁢ 
                           R 
                           ⁢ 
                           S 
                         
                       
                     
                     
                       N 
                       ⁢ 
                       
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                           D 
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                           ⁢ 
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                   - 
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                 ) 
               
             
           
         
       
     
     is the DMRS SNR determined or computed using only the energy level of the DMRS and the noise level of the DMRS, and 
     
       
         
           
             
               
                 E 
                 ⁢ 
                 
                   E 
                   
                     D 
                     ⁢ 
                     M 
                     ⁢ 
                     R 
                     ⁢ 
                     S 
                   
                 
               
               
                 E 
                 ⁢ 
                 
                   E 
                   
                     R 
                     ⁢ 
                     S 
                   
                 
               
             
             · 
             
               SNR 
               
                 R 
                 ⁢ 
                 S 
               
             
           
         
       
     
     is the modified or scaled RS-SNR, to determine whether to use the DMRS SNR determined or computed using only the energy level of the DMRS and the noise level of the DMRS. For example, if the ratio of the first SNR (e.g., the DMRS SNR determined or computed using only the energy level of the DMRS and the noise level of the DMRS) to the modified or scaled RS-SNR satisfies the threshold, then the UE  120  may use the first SNR as the DMRS SNR. If the ratio of the first SNR to the modified or scaled RS-SNR does not satisfy the threshold, then the UE  120  may use the modified or scaled RS-SNR as the DMRS SNR. 
     In some aspects, the UE  120  may determine whether to use the first SNR (e.g., the DMRS SNR determined or computed using only the energy level of the DMRS and the noise level of the DMRS) based at least in part on whether the first SNR is greater than the modified or scaled RS-SNR. In some aspects, the UE  120  may determine whether to use the first SNR based at least in part on whether the first SNR is greater than the modified or scaled RS-SNR that is modified by a threshold value (e.g., the same value as the threshold described above or a different value). For example, the UE  120  may use the equation 
     
       
         
           
             
               
                 ( 
                 
                   
                     
                       E 
                       ⁢ 
                       
                         E 
                         
                           D 
                           ⁢ 
                           M 
                           ⁢ 
                           R 
                           ⁢ 
                           S 
                         
                       
                     
                     
                       N 
                       ⁢ 
                       
                         E 
                         
                           D 
                           ⁢ 
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                           ⁢ 
                           R 
                           ⁢ 
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                   - 
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                 ) 
               
               &gt; 
               
                 thershold 
                 · 
                 
                   
                     E 
                     ⁢ 
                     
                       E 
                       
                         D 
                         ⁢ 
                         M 
                         ⁢ 
                         R 
                         ⁢ 
                         S 
                       
                     
                   
                   
                     E 
                     ⁢ 
                     
                       E 
                       
                         R 
                         ⁢ 
                         S 
                       
                     
                   
                 
                 · 
                 
                   SNR 
                   
                     R 
                     ⁢ 
                     S 
                   
                 
               
             
             , 
             
 
             
               where 
               ⁢ 
                   
               
                 ( 
                 
                   
                     
                       E 
                       ⁢ 
                       
                         E 
                         DMRS 
                       
                     
                     
                       N 
                       ⁢ 
                       
                         E 
                         DMRS 
                       
                     
                   
                   - 
                   1 
                 
                 ) 
               
             
           
         
       
     
     is the first SNR (e.g., the DMRS SNR determined or computed using only the energy level of the DMRS and the noise level of the DMRS), and 
     
       
         
           
             
               
                 E 
                 ⁢ 
                 
                   E 
                   
                     D 
                     ⁢ 
                     M 
                     ⁢ 
                     R 
                     ⁢ 
                     S 
                   
                 
               
               
                 E 
                 ⁢ 
                 
                   E 
                   
                     R 
                     ⁢ 
                     S 
                   
                 
               
             
             · 
             
               SNR 
               
                 R 
                 ⁢ 
                 S 
               
             
           
         
       
     
     is the modified or scaled RS-SNR, to determine whether to use the first SNR as the DMRS SNR. If the first SNR is greater than the modified or scaled RS-SNR that is modified by the threshold value, then the UE  120  may use the first SNR as the DMRS SNR. If the first SNR is less than or equal to the modified or scaled RS-SNR that is modified by the threshold value, then the UE  120  may use the modified or scaled RS-SNR as the DMRS SNR. 
     In some aspects, a value of the threshold may be a fixed value (e.g., 3 decibels or a similar value) for all UEs. In some aspects, a value of the threshold may be specific to the UE  120 . In some aspects, a value of the threshold may be variable and change over time. For example, a value of the threshold may be based at least in part on channel conditions experienced by the UE  120 . 
     As shown by reference number  425 , the UE  120  may perform channel estimation using the DMRS SNR (e.g., determined by the UE  120  as described above) to determine an estimated channel of a physical channel associated with a signal. For example, the UE  120  may use the DMRS SNR to determine an MMSE filter coefficient. The UE  120  may use the MMSE filter coefficient to determine an estimated channel for a physical channel associated with a signal. 
     In some aspects, the UE  120  may perform channel estimation to estimate a delay spread for the channel using the DMRS SNR (e.g., determined by the UE  120  as described above). For example, a multi-path channel may experience a delay spread due to delays at multiple paths (e.g., due to multi-path propagation). The UE  120  may perform delay spread estimation for the channel based at least in part on the DMRS SNR to improve the delay spread estimation when an SNR of a TRS or an SSB is low or unreliable. 
     For example, when there is an imbalance between the RS-SNR and the DMRS SNR, the UE  120  may use the DMRS SNR to improve or enhance the delay spread estimation. Typically, the UE  120  may relay on the RS-SNR (e.g., an SNR of a TRS or an SSB) to perform channel estimation. However, when the TRS or the SSB experiences interference or other differing parameters from the physical channel (e.g., as described above), delay spread estimations based on the SNR of a TRS or an SSB may be unreliable or result in an underestimation of the delay spread. For example, the UE  120  may detect that the TRS or the SSB is experiencing differing parameters from the physical channel (e.g., that the TRS or the SSB is experiencing a collision with another signal) based at least in part on a difference between the DMRS SNR and the RS-SNR. For example, if the difference between the DMRS SNR and the RS-SNR satisfies (e.g., is greater than or equal to) a collision threshold (e.g., 7 dB or similar values), then the UE  120  may determine or detect that that the TRS or the SSB is experiencing differing parameters from the physical channel (e.g., that the TRS or the SSB is experiencing a collision with another signal). Based at least in part on the difference between the DMRS SNR and the RS-SNR satisfying the collision threshold, the UE  120  may perform the delay spread estimation for the channel using the DMRS SNR. 
     In some aspects, the UE  120  may determine whether the RS-SNR (e.g., an SNR of a TRS or an SSB) satisfies a reliability threshold (e.g., 3 dB or similar values). If the RS-SNR satisfies the reliability threshold, then the UE  120  may use the RS-SNR to calculate the delay spread estimation and may use the DMRS SNR to set a threshold value (e.g., a delay spread threshold value) for separating a signal of the channel from noise over the estimated delay spread of the channel. For example, the UE  120  may use the threshold value to set a range from a strongest path (e.g., a dominant path associated with a highest power among paths received by the UE  120 ) to ensure that all of the most significant paths of the channel are identified or included in the range. For example, the threshold value may be a value that the UE  120  uses to capture paths that have an energy that is within the value from the energy of the strongest or dominant path received by the UE  120 . Therefore, using the DMRS SNR to set the threshold value (e.g., when the RS-SNR is unreliable as described above) improves the channel estimation by ensuring that the threshold value is set such that all (or a majority of) the most significant paths of the channel are identified by the UE  120  (e.g., by ensuring that energy of the most significant paths is within the threshold value from the energy of the best or dominant path). In other words, using the DMRS SNR to set the threshold value improves channel estimation by ensuring that the most significant paths of the channel are captured by the UE  120 . 
     In some aspects, the UE  120  may determine that the RS-SNR does not satisfy (e.g., is less than) the reliability threshold. Therefore, the RS-SNR may not be reliable enough or robust enough to use to estimate the channel delay spread. In other words, using the RS-SNR to compute the delay spread of the channel when the RS-SNR does not satisfy (e.g., is less than) the reliability threshold may result in delay spread underestimation that causes performance loss on fading channels. Therefore, if the RS-SNR does not satisfy the reliability threshold, the UE  120  may determine that the delay spread for the channel is a default value. For example, based at least in part on the difference between the DMRS SNR and the RS-SNR satisfying the collision threshold and based at least in part on the RS-SNR not satisfying the reliability threshold, the UE  120  may use a default value (e.g., a default delay spread value for the channel stored by the UE  120  or indicated to the UE  120 ) for the delay spread when performing channel estimation. 
     As a result, using the DMRS SNR to perform channel delay spread estimation may result in improved or enhanced channel estimation (e.g., compared to using only an RS-SNR for performing the channel delay spread estimation). For example, the UE  120  may be enabled to identify or detect when the TRS or the SSB is experiencing differing parameters from the physical channel (e.g., that the TRS or the SSB is experiencing a collision with another signal) based at least in part on a difference between the DMRS SNR and the RS-SNR. As a result, the UE  120  may use the DMRS SNR to improve the channel delay spread estimation, as described above. 
     As shown by reference number  430 , the UE  120  may perform demodulation processing of the signal using the estimated channel. For example, the UE  120  may use the estimated channel to perform demodulation processing of a signal to obtain data carried by the signal. The UE  120  may communicate (e.g., transmit or receive) one or more signals with the base station  110  based at least in part on performing demodulation processing of the signal using the estimated channel as described herein. As described above, by using the DMRS SNR described above, the UE  120  may ensure that an accurate channel estimation is performed to facilitate demodulation processing. Using an accurate channel estimation improves demodulation performance, improves throughput experienced by the UE  120 , and/or improves spectral efficiency experienced by the UE  120 , among other examples. 
     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 based SNR for demodulation processing, in accordance with the present disclosure. As shown in  FIG. 5 , example  500  depicts an example demodulation processing flow for a UE. 
     As shown by reference number  505 , the UE may perform demodulation processing (e.g., DMRS processing) of signals, using an estimated channel, to obtain data carried by the signal. As shown by reference number  510 , the UE may measure or identify, based at least in part on the DMRS processing, an energy level of a received DMRS (shown as EE-DMRS in  FIG. 5 ) and a noise level of a received DMRS (e.g., shown as NE-DMRS in  FIG. 5 ). The UE may combine (e.g., at a mixer shown by reference number  510 ) the energy level of the received DMRS and the noise level of the received DMRS. As shown by reference number  515 , the UE may subtract 1 from the combined energy level of the received DMRS and the noise level of the received DMRS to identify a first SNR that is based only on the received DMRS 
     
       
         
           
             
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     As shown by reference number  520 , the UE may perform reference signal processing of one or more received reference signals (e.g., TRSs or SSBs). Based at least in part on performing the reference signal processing, the UE may measure or identify an energy level of the reference signal (e.g., shown as EE-RS in  FIG. 5 ) and an RS-SNR of the reference signal. As shown by reference number  525 , the UE may combine the energy level of the DMRS and the energy level of the reference signal (e.g., at the mixer shown by reference number  525 ) to identify a value or a ratio 
     
       
         
           
             
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     As described above in connection with  FIG. 4 , the value or the ratio may indicate a beamforming gain of the DMRS compared to a beamforming gain of the reference signal (e.g., a ratio of, or a difference between, the beamforming gain of the DMRS and the beamforming gain of the reference signal). As shown by reference number  530 , the UE may modify the RS-SNR of the reference signal by the value or the ratio to determine a second SNR 
     
       
         
           
             
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     As shown by reference number  535 , the UE may determine or compute a DMRS SNR (e.g., the SNR to be used by the UE for channel estimation to facilitate demodulation processing) based at least in part on the first SNR (shown as A in  FIG. 5 ) and the second SNR (shown as B in  FIG. 5 ). As described above in connection with  FIG. 4 , in some aspects, the UE may use the first SNR as the DMRS SNR. Alternatively, the UE may use the second SNR as the DMRS SNR. 
     For example, in some aspects, the UE may determine whether to use the first SNR or the second SNR as the DMRS SNR. As described above in connection with  FIG. 4 , the UE may use a threshold value to compare the first SNR and the second SNR to determine whether to use the first SNR or the second SNR as the DMRS SNR. For example, the UE may determine whether a ratio of the first SNR to the second SNR (e.g., the first SNR divided by the second SNR) satisfies the threshold. If the ratio of the first SNR to the second SNR satisfies the threshold, then the UE may use the first SNR as the DMRS SNR. If the ratio of the first SNR to the second SNR does not satisfy the threshold, then the UE may use the second SNR as the DMRS SNR. 
     In some aspects, the UE may modify the second SNR by a value of the threshold. The UE may determine whether the first SNR is greater than the modified second SNR. If the first SNR is greater than the modified second SNR, then the UE may use the first SNR as the DMRS SNR. If the first SNR is less than or equal to the modified second SNR, then the UE may use the second SNR as the DMRS SNR. 
     As shown by reference number  540 , the UE may provide the determined DMRS SNR to an MMSE filter. The UE, using the MMSE filter, may determine an MMSE filter coefficient based at least in part on the DMRS SNR. The UE may provide the MMSE filter coefficient to a demodulation processing component (e.g., a DMRS processing component). The UE may use the MMSE filter coefficient for channel estimation of a physical channel. For example, the UE may perform a channel estimation based at least in part on the DMRS SNR (e.g., using the MMSE filter coefficient) to determine an estimated channel of the physical channel. The UE may perform demodulation of a signal, using the estimated channel, to obtain data carried by the signal. As described above, by determining or identifying the DMRS SNR as described above, the UE may obtain a more accurate channel estimation to facilitate demodulation processing. As a result, demodulation performance of the UE is improved. 
     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 an example process  600  performed, for example, by a UE, in accordance with the present disclosure. Example process  600  is an example where the UE (e.g., UE  120 ) performs operations associated with DMRS based SNR for demodulation processing. 
     As shown in  FIG. 6 , in some aspects, process  600  may include measuring a first energy level of a DMRS (block  610 ). For example, the UE (e.g., using measurement component  708 , depicted in  FIG. 7 ) may measure a first energy level of a DMRS, as described above. 
     As further shown in  FIG. 6 , in some aspects, process  600  may include measuring a second energy level of at least one of a TRS or an SSB (block  620 ). For example, the UE (e.g., using measurement component  708 , depicted in  FIG. 7 ) may measure a second energy level of at least one of a TRS or an SSB, as described above. 
     As further shown in  FIG. 6 , in some aspects, process  600  may include determining, based at least in part on the first energy level and the second energy level, a DMRS SNR (block  630 ). For example, the UE (e.g., using determination component  710 , depicted in  FIG. 7 ) may determine, based at least in part on the first energy level and the second energy level, a DMRS SNR, as described above. 
     As further shown in  FIG. 6 , in some aspects, process  600  may include performing, based at least in part on the DMRS SNR, channel estimation for a physical channel associated with a communication to determine an estimated channel (block  640 ). For example, the UE (e.g., using channel estimation component  712 , depicted in  FIG. 7 ) may perform, based at least in part on the DMRS SNR, channel estimation for a physical channel associated with a communication to determine an estimated channel, as described above. 
     As further shown in  FIG. 6 , in some aspects, process  600  may include performing, based at least in part on the estimated channel, demodulation processing for the communication (block  650 ). For example, the UE (e.g., using demodulation component  714 , depicted in  FIG. 7 ) may perform, based at least in part on the estimated channel, demodulation processing for the communication, as described above. 
     Process  600  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, process  600  includes receiving, using a beam that is selected based at least in part on at least one of the TRS or the SSB, the communication on the physical channel. 
     In a second aspect, alone or in combination with the first aspect, process  600  includes measuring an RS-SNR that is based at least in part on the second energy level. 
     In a third aspect, alone or in combination with one or more of the first and second aspects, the determination of the DMRS SNR includes determining the DMRS SNR for at least one of a slot during which the communication is received, an antenna port used for receiving the communication, or a DMRS port associated with the DMRS. 
     In a fourth aspect, alone or in combination with one or more of the first through third aspects, the determination of the DMRS SNR includes measuring the DMRS SNR based at least in part on at least one of the first energy level, the second energy level, a noise level associated with the DMRS, or an RS-SNR that is based at least in part on the second energy level. 
     In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the determination of the DMRS SNR includes measuring a noise level associated with the DMRS, and determining, based at least in part on the first energy level and the noise level, the DMRS SNR. 
     In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the determination of the DMRS SNR includes determining, based at least in part on the first energy level and the second energy level, a value, measuring an RS-SNR that is based at least in part on the second energy level, and modifying the RS-SNR by the value to obtain the DMRS SNR. 
     In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the determination of the value includes determining the value based at least in part on a function of the first energy level and the second energy level. 
     In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, the determination of the DMRS SNR includes determining, based at least in part on the first energy level and a measured noise level associated with the DMRS, a first SNR, modifying an RS-SNR, that is based at least in part on the second energy level, by a first value to obtain a second SNR, determining whether a ratio, of the first SNR to the second SNR, satisfies a threshold, and determining that the DMRS SNR is the first SNR if the ratio of the first SNR to the second SNR satisfies the threshold, or the second SNR if the ratio of the first SNR to the second SNR does not satisfy the threshold. 
     In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, the determination of the DMRS SNR includes determining, based at least in part on the first energy level and a measured noise level associated with the DMRS, a first SNR, modifying an RS-SNR, that is based at least in part on the second energy level, by a first value to obtain a second SNR, modifying the second SNR by a second value to obtain a third SNR, and determining that the DMRS SNR is the first SNR if the first SNR is greater than the third SNR, or the second SNR if the first SNR is less than or equal to the third SNR. 
     In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, the UE is operating in a millimeter wave operating frequency. 
     In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, performing the channel estimation includes performing a delay spread estimation for the channel based at least in part on the DMRS SNR. 
     In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, performing the delay spread estimation includes measuring an RS-SNR that is based at least in part on the second energy level; comparing the RS-SNR to the DMRS SNR to obtain a difference between the RS-SNR and the DMRS SNR; and performing the delay spread estimation for the channel using the DMRS SNR based at least in part on the difference between the RS-SNR and the DMRS SNR satisfying a collision threshold. 
     In a thirteenth aspect, alone or in combination with one or more of the first through twelfth aspects, performing the delay spread estimation for the channel using the DMRS SNR includes performing, if the RS-SNR satisfies a reliability threshold, the delay spread estimation for the channel using the DMRS SNR to set a threshold value for separating a signal of the channel from noise over the estimated delay spread of the channel. 
     In a fourteenth aspect, alone or in combination with one or more of the first through thirteenth aspects, performing the delay spread estimation for the channel using the DMRS SNR includes determining, if the RS-SNR does not satisfy a reliability threshold, that the delay spread for the channel is a default value. 
     Although  FIG. 6  shows example blocks of process  600 , in some aspects, process  600  may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in  FIG. 6 . Additionally, or alternatively, two or more of the blocks of process  600  may be performed in parallel. 
       FIG. 7  is a block diagram of an example apparatus  700  for wireless communication. The apparatus  700  may be a UE, or a UE may include the apparatus  700 . In some aspects, the apparatus  700  includes a reception component  702  and a transmission component  704 , 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  700  may communicate with another apparatus  706  (such as a UE, a base station, or another wireless communication device) using the reception component  702  and the transmission component  704 . As further shown, the apparatus  700  may include one or more of a measurement component  708 , a determination component  710 , a channel estimation component  712 , or a demodulation component  714 , among other examples. 
     In some aspects, the apparatus  700  may be configured to perform one or more operations described herein in connection with  FIGS. 4 and 5 . Additionally, or alternatively, the apparatus  700  may be configured to perform one or more processes described herein, such as process  600  of  FIG. 6 , or a combination thereof. In some aspects, the apparatus  700  and/or one or more components shown in  FIG. 7  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. 7  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  702  may receive communications, such as reference signals, control information, data communications, or a combination thereof, from the apparatus  706 . The reception component  702  may provide received communications to one or more other components of the apparatus  700 . In some aspects, the reception component  702  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  706 . In some aspects, the reception component  702  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  704  may transmit communications, such as reference signals, control information, data communications, or a combination thereof, to the apparatus  706 . In some aspects, one or more other components of the apparatus  706  may generate communications and may provide the generated communications to the transmission component  704  for transmission to the apparatus  706 . In some aspects, the transmission component  704  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  706 . In some aspects, the transmission component  704  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  704  may be co-located with the reception component  702  in a transceiver. 
     The measurement component  708  may measure a first energy level of a DMRS. The measurement component  708  may measure a second energy level of at least one of a TRS or an SSB. The determination component  710  may determine, based at least in part on the first energy level and the second energy level, a DMRS SNR. The channel estimation component  712  may perform, based at least in part on the DMRS SNR, channel estimation for a physical channel associated with a communication to determine an estimated channel. The demodulation component  714  may perform, based at least in part on the estimated channel, demodulation processing for the communication. 
     The reception component  702  may receive, using a beam that is selected based at least in part on at least one of the TRS or the SSB, the communication on the physical channel. 
     The measurement component  708  may measure an RS-SNR that is based at least in part on the second energy level. 
     The determination component  710  may determine the DMRS SNR for at least one of: a slot during which the communication is received, an antenna port used for receiving the communication, or a DMRS port associated with the DMRS. 
     The measurement component  708  and/or the determination component  710  may measure the DMRS SNR based at least in part on at least one of: the first energy level, the second energy level, a noise level associated with the DMRS, or a RS-SNR that is based at least in part on the second energy level. 
     The measurement component  708  may measure a noise level associated with the DMRS. The determination component  710  may determine, based at least in part on the first energy level and the noise level, the DMRS SNR. 
     The determination component  710  may determine, based at least in part on the first energy level and the second energy level, a value. The measurement component  708  may measure an RS-SNR that is based at least in part on the second energy level. The determination component  710  may modify the RS-SNR by the value to obtain the DMRS SNR. 
     The determination component  710  may determine the value based at least in part on a function of the first energy level and the second energy level. 
     The determination component  710  may determine, based at least in part on the first energy level and a measured noise level associated with the DMRS, a first SNR. The determination component  710  may modify an RS-SNR, that is based at least in part on the second energy level, by a first value to obtain a second SNR. The determination component  710  may determine whether a ratio, of the first SNR to the second SNR, satisfies a threshold. The determination component  710  may determine that the DMRS SNR is the first SNR if the ratio of the first SNR to the second SNR satisfies the threshold, or the second SNR if the ratio of the first SNR to the second SNR does not satisfy the threshold. 
     The determination component  710  may determine, based at least in part on the first energy level and a measured noise level associated with the DMRS, a first SNR. The determination component  710  may modify an RS-SNR, that is based at least in part on the second energy level, by a first value to obtain a second SNR. The determination component  710  may modify the second SNR by a second value to obtain a third SNR. The determination component  710  may determine that the DMRS SNR is the first SNR if the first SNR is greater than the third SNR, or the second SNR if the first SNR is less than or equal to the third SNR. 
     The channel estimation component  712  may perform a delay spread estimation for the channel based at least in part on the DMRS SNR. 
     The number and arrangement of components shown in  FIG. 7  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. 7 . Furthermore, two or more components shown in  FIG. 7  may be implemented within a single component, or a single component shown in  FIG. 7  may be implemented as multiple, distributed components. Additionally, or alternatively, a set of (one or more) components shown in  FIG. 7  may perform one or more functions described as being performed by another set of components shown in  FIG. 7 . 
       FIG. 8  is a block diagram of an example apparatus  800  for wireless communication. The apparatus  800  may be a base station, or a base station may include the apparatus  800 . In some aspects, the apparatus  800  includes a reception component  802  and a transmission component  804 , 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  800  may communicate with another apparatus  806  (such as a UE, a base station, or another wireless communication device) using the reception component  802  and the transmission component  804 . As further shown, the apparatus  800  may include a determination component  808 , among other examples. 
     In some aspects, the apparatus  800  may be configured to perform one or more operations described herein in connection with  FIGS. 4 and 5 . Additionally, or alternatively, the apparatus  800  may be configured to perform one or more processes described herein, or a combination thereof. In some aspects, the apparatus  800  and/or one or more components shown in  FIG. 8  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. 8  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  802  may receive communications, such as reference signals, control information, data communications, or a combination thereof, from the apparatus  806 . The reception component  802  may provide received communications to one or more other components of the apparatus  800 . In some aspects, the reception component  802  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  806 . In some aspects, the reception component  802  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  804  may transmit communications, such as reference signals, control information, data communications, or a combination thereof, to the apparatus  806 . In some aspects, one or more other components of the apparatus  806  may generate communications and may provide the generated communications to the transmission component  804  for transmission to the apparatus  806 . In some aspects, the transmission component  804  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  806 . In some aspects, the transmission component  804  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  804  may be co-located with the reception component  802  in a transceiver. 
     The transmission component  804  may transmit, to a UE, a DMRS. The transmission component  804  may transmit, to the UE, at least one of a TRS or an SSB. The transmission component may transmit, to the UE, a communication that is to be demodulated by the UE based at least in part on an energy level of the DMRS (at the UE) and an energy level of the TRS or the SSB (at the UE). The determination component  808  may determine or select a beam to use to transmit the communication based at least on at least one of the TRS or the SSB. 
     The number and arrangement of components shown in  FIG. 8  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. 8 . Furthermore, two or more components shown in  FIG. 8  may be implemented within a single component, or a single component shown in  FIG. 8  may be implemented as multiple, distributed components. Additionally, or alternatively, a set of (one or more) components shown in  FIG. 8  may perform one or more functions described as being performed by another set of components shown in  FIG. 8 . 
     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: measuring a first energy level of a demodulation reference signal (DMRS); measuring a second energy level of at least one of a tracking reference signal (TRS) or a synchronization signal block (SSB); determining, based at least in part on the first energy level and the second energy level, a DMRS signal-to-noise ratio (SNR); performing, based at least in part on the DMRS SNR, channel estimation for a physical channel associated with a communication to determine an estimated channel; and performing, based at least in part on the estimated channel, demodulation processing for the communication. 
     Aspect 2: The method of aspect 1, further comprising: receiving, using a beam that is selected based at least in part on at least one of the TRS or the SSB, the communication on the physical channel. 
     Aspect 3: The method of any of aspects 1-2, further comprising: measuring a reference signal SNR (RS-SNR) that is based at least in part on the second energy level. 
     Aspect 4: The method of any of aspects 1-3, wherein the determination of the DMRS SNR comprises: determining the DMRS SNR for at least one of: a slot during which the communication is received, an antenna port used for receiving the communication, or a DMRS port associated with the DMRS. 
     Aspect 5: The method of any of aspects 1-4, wherein the determination of the DMRS SNR comprises: measuring the DMRS SNR based at least in part on at least one of: the first energy level, the second energy level, a noise level associated with the DMRS, or a reference signal SNR (RS-SNR) that is based at least in part on the second energy level. 
     Aspect 6: The method of any of aspects 1-5, wherein the determination of the DMRS SNR comprises: measuring a noise level associated with the DMRS; and determining, based at least in part on the first energy level and the noise level, the DMRS SNR. 
     Aspect 7: The method of any of aspects 1-5, wherein the determination of the DMRS SNR comprises: determining, based at least in part on the first energy level and the second energy level, a value; measuring a reference signal SNR (RS-SNR) that is based at least in part on the second energy level; and modifying the RS-SNR by the value to obtain the DMRS SNR. 
     Aspect 8: The method of aspect 7, wherein the determination of the value comprises: determining the value based at least in part on a function of the first energy level and the second energy level. 
     Aspect 9: The method of any of aspects 1-5, wherein the determination of the DMRS SNR comprises: determining, based at least in part on the first energy level and a measured noise level associated with the DMRS, a first SNR; modifying a reference signal SNR (RS-SNR), that is based at least in part on the second energy level, by a first value to obtain a second SNR; determining whether a ratio, of the first SNR to the second SNR, satisfies a threshold; and determining that the DMRS SNR is: the first SNR if the ratio of the first SNR to the second SNR satisfies the threshold, or the second SNR if the ratio of the first SNR to the second SNR does not satisfy the threshold. 
     Aspect 10: The method of any of aspects 1-5, wherein the determination of the DMRS SNR comprises: determining, based at least in part on the first energy level and a measured noise level associated with the DMRS, a first SNR; modifying a reference signal SNR (RS-SNR), that is based at least in part on the second energy level, by a first value to obtain a second SNR; modifying the second SNR by a second value to obtain a third SNR; and determining that the DMRS SNR is: the first SNR if the first SNR is greater than the third SNR, or the second SNR if the first SNR is less than or equal to the third SNR. 
     Aspect 11: The method of any of aspects 1-10, wherein the UE is operating in a millimeter wave operating frequency. 
     Aspect 12: The method of any of aspects 1-11, wherein performing the channel estimation comprises: performing a delay spread estimation for the channel based at least in part on the DMRS SNR. 
     Aspect 13: The method of aspect 12, wherein performing the delay spread estimation comprises: measuring a reference signal SNR (RS-SNR) that is based at least in part on the second energy level; comparing the RS-SNR to the DMRS SNR to obtain a difference between the RS-SNR and the DMRS SNR; and performing the delay spread estimation for the channel using the DMRS SNR based at least in part on the difference between the RS-SNR and the DMRS SNR satisfying a collision threshold. 
     Aspect 14: The method of aspect 13, wherein performing the delay spread estimation for the channel using the DMRS SNR comprises: performing, if the RS-SNR satisfies a reliability threshold, the delay spread estimation for the channel using the DMRS SNR to set a threshold value for separating a signal of the channel from noise over the estimated delay spread of the channel. 
     Aspect 15: The method of aspect 13, wherein performing the delay spread estimation for the channel using the DMRS SNR comprises: determining, if the RS-SNR does not satisfy a reliability threshold, that the delay spread for the channel is a default value. 
     Aspect 16: An apparatus for wireless communication at a device, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method of one or more aspects of aspects 1-15. 
     Aspect 17: A device for wireless communication, comprising a memory and one or more processors coupled to the memory, the memory and the one or more processors configured to perform the method of one or more aspects of aspects 1-15. 
     Aspect 18: An apparatus for wireless communication, comprising at least one means for performing the method of one or more aspects of aspects 1-15. 
     Aspect 19: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method of one or more aspects of aspects 1-15. 
     Aspect 20: A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform the method of one or more aspects of aspects 1-15. 
     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, firmware, and/or a combination of hardware and software. As used herein, a processor is implemented in hardware, firmware, 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, firmware, 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”).