Patent Publication Number: US-11665687-B2

Title: Common measurement and transmission window for downlink and uplink positioning reference signal processing and transmission

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present Application for Patent claims the benefit of U.S. Provisional Application No. 62/932,323, entitled “COMMON MEASUREMENT AND TRANSMISSION WINDOW FOR DOWNLINK AND UPLINK POSITIONING REFERENCE SIGNAL PROCESSING AND TRANSMISSION,” filed Nov. 7, 2019, assigned to the assignee hereof, and expressly incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE DISCLOSURE 
     1. Field of the Disclosure 
     Aspects of the disclosure relate generally to wireless communications. 
     2. Description of the Related Art 
     Wireless communication systems have developed through various generations, including a first-generation analog wireless phone service (1G), a second-generation (2G) digital wireless phone service (including interim 2.5G networks), a third-generation (3G) high speed data, Internet-capable wireless service and a fourth-generation (4G) service (e.g., LTE or WiMax). There are presently many different types of wireless communication systems in use, including cellular and personal communications service (PCS) systems. Examples of known cellular systems include the cellular analog advanced mobile phone system (AMPS), and digital cellular systems based on code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), the Global System for Mobile communication (GSM), etc. 
     A fifth generation (5G) wireless standard, referred to as New Radio (NR), enables higher data transfer speeds, greater numbers of connections, and better coverage, among other improvements. The 5G standard, according to the Next Generation Mobile Networks Alliance, is designed to provide data rates of several tens of megabits per second to each of tens of thousands of users, with 1 gigabit per second to tens of workers on an office floor. Several hundreds of thousands of simultaneous connections should be supported in order to support large wireless sensor deployments. Consequently, the spectral efficiency of 5G mobile communications should be significantly enhanced compared to the current 4G standard. Furthermore, signaling efficiencies should be enhanced and latency should be substantially reduced compared to current standards. 
     SUMMARY 
     The following presents a simplified summary relating to one or more aspects disclosed herein. Thus, the following summary should not be considered an extensive overview relating to all contemplated aspects, nor should the following summary be considered to identify key or critical elements relating to all contemplated aspects or to delineate the scope associated with any particular aspect. Accordingly, the following summary has the sole purpose to present certain concepts relating to one or more aspects relating to the mechanisms disclosed herein in a simplified form to precede the detailed description presented below. 
     In an aspect, a method of wireless communication performed by a user equipment (UE) engaged in a positioning session with a plurality of transmission-reception points (TRPs) includes receiving a downlink positioning reference signal (DL-PRS) configuration specifying one or more DL-PRS resource sets of a DL-PRS instance, wherein each DL-PRS resource set is associated with a TRP of the plurality of TRPs, is configured with a transmission periodicity, comprises one or more DL-PRS resources that are transmitted according to the configured transmission periodicity of the DL-PRS resource set, wherein each DL-PRS resource is scheduled to be repeated over one or more consecutive slots, wherein one transmission instance of a repetition of the one or more DL-PRS resources of the one or more DL-PRS resource sets corresponds to a DL-PRS instance, wherein all DL-PRS resources of the one or more DL-PRS resource sets of the DL-PRS instance are scheduled within a time window, and wherein a duration of the time window is less than a duration defined by a configured transmission periodicity of one of the one or more DL-PRS resource sets; and receiving an uplink PRS (UL-PRS) configuration specifying one or more UL-PRS resource sets, wherein each UL-PRS resource set comprises one or more UL-PRS resources, and wherein all of the one or more UL-PRS are scheduled within the time window. 
     In an aspect, a method of wireless communication performed by a positioning entity includes transmitting, to a UE engaged in a positioning session with a plurality of TRPs, a DL-PRS configuration specifying one or more DL-PRS resource sets of a DL-PRS instance, wherein each DL-PRS resource set is associated with a TRP of the plurality of TRPs, is configured with a transmission periodicity, comprises one or more DL-PRS resources that are transmitted according to the configured transmission periodicity of the DL-PRS resource set, wherein each DL-PRS resource is scheduled to be repeated over one or more consecutive slots, wherein one transmission instance of a repetition of the one or more DL-PRS resources of the one or more DL-PRS resource sets corresponds to a DL-PRS instance, wherein all DL-PRS resources of the one or more DL-PRS resource sets of the DL-PRS instance are scheduled within a time window, and wherein a duration of the time window is less than a duration defined by a configured transmission periodicity of one of the one or more DL-PRS resource sets; and transmitting, to the UE, an UL-PRS configuration specifying one or more UL-PRS resource sets, wherein each UL-PRS resource set comprises one or more UL-PRS resources, and wherein all of the one or more UL-PRS are scheduled within the time window. 
     In an aspect, a UE includes a memory; at least one transceiver; and at least one processor communicatively coupled to the memory and the at least one transceiver, the at least one processor configured to: receive, during a positioning session with a plurality of TRPs, via the at least one transceiver, a DL-PRS configuration specifying one or more DL-PRS resource sets, wherein each DL-PRS resource set is associated with a TRP of the plurality of TRPs, is configured with a transmission periodicity, comprises one or more DL-PRS resources that are transmitted according to the configured transmission periodicity of the DL-PRS resource set, wherein each DL-PRS resource is scheduled to be repeated over one or more consecutive slots, wherein one transmission instance of a repetition of the one or more DL-PRS resources of the one or more DL-PRS resource sets corresponds to a DL-PRS instance, wherein all DL-PRS resources of the one or more DL-PRS resource sets of the DL-PRS instance are scheduled within a time window, and wherein a duration of the time window is less than a duration defined by a configured transmission periodicity of one of the one or more DL-PRS resource sets; and receive, via the at least one transceiver, an UL-PRS configuration specifying one or more UL-PRS resource sets, wherein each UL-PRS resource set comprises one or more UL-PRS resources, and wherein the one or more UL-PRS resources are scheduled within the time window. 
     In an aspect, a positioning entity includes a memory; at least one network interface; and at least one processor communicatively coupled to the memory and the at least one processor, the at least one processor configured to: cause the at least one network interface to transmit, to a UE engaged in a positioning session with a plurality of TRPs, a DL-PRS configuration specifying one or more DL-PRS resource sets of a DL-PRS instance, wherein each DL-PRS resource set is associated with a TRP of the plurality of TRPs, is configured with a transmission periodicity, comprises one or more DL-PRS resources that are transmitted according to the configured transmission periodicity of the DL-PRS resource set, wherein each DL-PRS resource is scheduled to be repeated over one or more consecutive slots, wherein one transmission instance of a repetition of the one or more DL-PRS resources of the one or more DL-PRS resource sets corresponds to a DL-PRS instance, wherein all DL-PRS resources of the one or more DL-PRS resource sets of the DL-PRS instance are scheduled within a time window, and wherein a duration of the time window is less than a duration defined by a configured transmission periodicity of one of the one or more DL-PRS resource sets; and cause the at least one network interface to transmit, to the UE, an UL-PRS configuration specifying one or more UL-PRS resource sets, wherein each UL-PRS resource set comprises one or more UL-PRS resources, and wherein the one or more UL-PRS resources are scheduled within the time window. 
     In an aspect, a UE includes means for receiving, during a positioning session with a plurality of TRPs, a DL-PRS configuration specifying one or more DL-PRS resource sets, wherein each DL-PRS resource set is associated with a TRP of the plurality of TRPs, is configured with a transmission periodicity, comprises one or more DL-PRS resources that are transmitted according to the configured transmission periodicity of the DL-PRS resource set, wherein each DL-PRS resource is scheduled to be repeated over one or more consecutive slots, wherein one transmission instance of a repetition of the one or more DL-PRS resources of the one or more DL-PRS resource sets corresponds to a DL-PRS instance, wherein all DL-PRS resources of the one or more DL-PRS resource sets of the DL-PRS instance are scheduled within a time window, and wherein a duration of the time window is less than a duration defined by a configured transmission periodicity of one of the one or more DL-PRS resource sets; and means for receiving an UL-PRS configuration specifying one or more UL-PRS resource sets, wherein each UL-PRS resource set comprises one or more UL-PRS resources, and wherein the one or more UL-PRS resources are scheduled within the time window. 
     In an aspect, a positioning entity includes means for transmitting, to a UE engaged in a positioning session with a plurality of TRPs, a DL-PRS configuration specifying one or more DL-PRS resource sets of a DL-PRS instance, wherein each DL-PRS resource set is associated with a TRP of the plurality of TRPs, is configured with a transmission periodicity, comprises one or more DL-PRS resources that are transmitted according to the configured transmission periodicity of the DL-PRS resource set, wherein each DL-PRS resource is scheduled to be repeated over one or more consecutive slots, wherein one transmission instance of a repetition of the one or more DL-PRS resources of the one or more DL-PRS resource sets corresponds to a DL-PRS instance, wherein all DL-PRS resources of the one or more DL-PRS resource sets of the DL-PRS instance are scheduled within a time window, and wherein a duration of the time window is less than a duration defined by a configured transmission periodicity of one of the one or more DL-PRS resource sets; and means for transmitting, to the UE, an UL-PRS configuration specifying one or more UL-PRS resource sets, wherein each UL-PRS resource set comprises one or more UL-PRS resources, and wherein the one or more UL-PRS resources are scheduled within the time window. 
     In an aspect, a non-transitory computer-readable medium storing computer-executable instructions includes computer-executable instructions comprising: at least one instruction instructing a UE engaged in a positioning session with a plurality of TRPs to receive a DL-PRS configuration specifying one or more DL-PRS resource sets, wherein each DL-PRS resource set is associated with a TRP of the plurality of TRPs, is configured with a transmission periodicity, comprises one or more DL-PRS resources that are transmitted according to the configured transmission periodicity of the DL-PRS resource set, wherein each DL-PRS resource is scheduled to be repeated over one or more consecutive slots, wherein one transmission instance of a repetition of the one or more DL-PRS resources of the one or more DL-PRS resource sets corresponds to a DL-PRS instance, wherein all DL-PRS resources of the one or more DL-PRS resource sets of the DL-PRS instance are scheduled within a time window, and wherein a duration of the time window is less than a duration defined by a configured transmission periodicity of one of the one or more DL-PRS resource sets; and at least one instruction instructing the UE to receive an UL-PRS configuration specifying one or more UL-PRS resource sets, wherein each UL-PRS resource set comprises one or more UL-PRS resources, and wherein the one or more UL-PRS resources are scheduled within the time window. 
     In an aspect, a non-transitory computer-readable medium storing computer-executable instructions includes computer-executable instructions comprising: at least one instruction instructing a positioning entity to transmit, to a UE engaged in a positioning session with a plurality of TRPs, a DL-PRS configuration specifying one or more DL-PRS resource sets of a DL-PRS instance, wherein each DL-PRS resource set is associated with a TRP of the plurality of TRPs, is configured with a transmission periodicity, comprises one or more DL-PRS resources that are transmitted according to the configured transmission periodicity of the DL-PRS resource set, wherein each DL-PRS resource is scheduled to be repeated over one or more consecutive slots, wherein one transmission instance of a repetition of the one or more DL-PRS resources of the one or more DL-PRS resource sets corresponds to a DL-PRS instance, wherein all DL-PRS resources of the one or more DL-PRS resource sets of the DL-PRS instance are scheduled within a time window, and wherein a duration of the time window is less than a duration defined by a configured transmission periodicity of one of the one or more DL-PRS resource sets; and at least one instruction instructing the positioning entity to transmit, to the UE, an UL-PRS configuration specifying one or more UL-PRS resource sets, wherein each UL-PRS resource set comprises one or more UL-PRS resources, and wherein the one or more UL-PRS resources are scheduled within the time window. 
     Other objects and advantages associated with the aspects disclosed herein will be apparent to those skilled in the art based on the accompanying drawings and detailed description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings are presented to aid in the description of various aspects of the disclosure and are provided solely for illustration of the aspects and not limitation thereof. 
         FIG.  1    illustrates an exemplary wireless communications system, according to various aspects. 
         FIGS.  2 A and  2 B  illustrate example wireless network structures, according to various aspects. 
         FIGS.  3 A to  3 C  are simplified block diagrams of several sample aspects of components that may be employed in a user equipment (UE), a base station, and a network entity, respectively. 
         FIGS.  4 A to  4 D  are diagrams illustrating examples of frame structures and channels within the frame structures, according to aspects of the disclosure. 
         FIG.  5    illustrates an exemplary positioning reference signal (PRS) configuration for a cell supported by a wireless node. 
         FIG.  6    is a diagram of downlink PRS transmissions and uplink PRS transmissions between a base station and two UEs, according to aspects of the disclosure. 
         FIG.  7    is a diagram of a common measurement/transmission window during which both downlink PRS resources and uplink PRS resources are scheduled for a given UE, according to aspects of the disclosure. 
         FIG.  8    is a diagram of multiple measurement/transmission windows during which both downlink PRS resources and uplink PRS resources are scheduled for a given UE, according to aspects of the disclosure. 
         FIGS.  9  and  10    illustrate methods of wireless communication, according to aspects of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Aspects of the disclosure are provided in the following description and related drawings directed to various examples provided for illustration purposes. Alternate aspects may be devised without departing from the scope of the disclosure. Additionally, well-known elements of the disclosure will not be described in detail or will be omitted so as not to obscure the relevant details of the disclosure. 
     The words “exemplary” and/or “example” are used herein to mean “serving as an example, instance, or illustration.” Any aspect described herein as “exemplary” and/or “example” is not necessarily to be construed as preferred or advantageous over other aspects. Likewise, the term “aspects of the disclosure” does not require that all aspects of the disclosure include the discussed feature, advantage or mode of operation. 
     Those of skill in the art will appreciate that the information and signals described below may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description below may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof, depending in part on the particular application, in part on the desired design, in part on the corresponding technology, etc. 
     Further, many aspects are described in terms of sequences of actions to be performed by, for example, elements of a computing device. It will be recognized that various actions described herein can be performed by specific circuits (e.g., application specific integrated circuits (ASICs)), by program instructions being executed by one or more processors, or by a combination of both. Additionally, the sequence(s) of actions described herein can be considered to be embodied entirely within any form of non-transitory computer-readable storage medium having stored therein a corresponding set of computer instructions that, upon execution, would cause or instruct an associated processor of a device to perform the functionality described herein. Thus, the various aspects of the disclosure may be embodied in a number of different forms, all of which have been contemplated to be within the scope of the claimed subject matter. In addition, for each of the aspects described herein, the corresponding form of any such aspects may be described herein as, for example, “logic configured to” perform the described action. 
     As used herein, the terms “user equipment” (UE) and “base station” are not intended to be specific or otherwise limited to any particular radio access technology (RAT), unless otherwise noted. In general, a UE may be any wireless communication device (e.g., a mobile phone, router, tablet computer, laptop computer, tracking device, wearable (e.g., smartwatch, glasses, augmented reality (AR)/virtual reality (VR) headset, etc.), vehicle (e.g., automobile, motorcycle, bicycle, etc.), Internet of Things (IoT) device, etc.) used by a user to communicate over a wireless communications network. A UE may be mobile or may (e.g., at certain times) be stationary, and may communicate with a radio access network (RAN). As used herein, the term “UE” may be referred to interchangeably as an “access terminal” or “AT,” a “client device,” a “wireless device,” a “subscriber device,” a “subscriber terminal,” a “subscriber station,” a “user terminal” or UT, a “mobile device,” a “mobile terminal,” a “mobile station,” or variations thereof. Generally, UEs can communicate with a core network via a RAN, and through the core network the UEs can be connected with external networks such as the Internet and with other UEs. Of course, other mechanisms of connecting to the core network and/or the Internet are also possible for the UEs, such as over wired access networks, wireless local area network (WLAN) networks (e.g., based on IEEE 802.11, etc.) and so on. 
     A base station may operate according to one of several RATs in communication with UEs depending on the network in which it is deployed, and may be alternatively referred to as an access point (AP), a network node, a NodeB, an evolved NodeB (eNB), a next generation eNB (ng-eNB), a New Radio (NR) Node B (also referred to as a gNB or gNodeB), etc. A base station may be used primarily to support wireless access by UEs, including supporting data, voice, and/or signaling connections for the supported UEs. In some systems a base station may provide purely edge node signaling functions while in other systems it may provide additional control and/or network management functions. A communication link through which UEs can send signals to a base station is called an uplink (UL) channel (e.g., a reverse traffic channel, a reverse control channel, an access channel, etc.). A communication link through which the base station can send signals to UEs is called a downlink (DL) or forward link channel (e.g., a paging channel, a control channel, a broadcast channel, a forward traffic channel, etc.). As used herein the term traffic channel (TCH) can refer to either an uplink/reverse or downlink/forward traffic channel. 
     The term “base station” may refer to a single physical transmission-reception point (TRP) or to multiple physical TRPs that may or may not be co-located. For example, where the term “base station” refers to a single physical TRP, the physical TRP may be an antenna of the base station corresponding to a cell (or several cell sectors) of the base station. Where the term “base station” refers to multiple co-located physical TRPs, the physical TRPs may be an array of antennas (e.g., as in a multiple-input multiple-output (MIMO) system or where the base station employs beamforming) of the base station. Where the term “base station” refers to multiple non-co-located physical TRPs, the physical TRPs may be a distributed antenna system (DAS) (a network of spatially separated antennas connected to a common source via a transport medium) or a remote radio head (RRH) (a remote base station connected to a serving base station). Alternatively, the non-co-located physical TRPs may be the serving base station receiving the measurement report from the UE and a neighbor base station whose reference RF signals (or simply “reference signals”) the UE is measuring. Because a TRP is the point from which a base station transmits and receives wireless signals, as used herein, references to transmission from or reception at a base station are to be understood as referring to a particular TRP of the base station. 
     In some implementations that support positioning of UEs, a base station may not support wireless access by UEs (e.g., may not support data, voice, and/or signaling connections for UEs), but may instead transmit reference signals to UEs to be measured by the UEs, and/or may receive and measure signals transmitted by the UEs. Such a base station may be referred to as a positioning beacon (e.g., when transmitting signals to UEs) and/or as a location measurement unit (e.g., when receiving and measuring signals from UEs). 
     An “RF signal” comprises an electromagnetic wave of a given frequency that transports information through the space between a transmitter and a receiver. As used herein, a transmitter may transmit a single “RF signal” or multiple “RF signals” to a receiver. However, the receiver may receive multiple “RF signals” corresponding to each transmitted RF signal due to the propagation characteristics of RF signals through multipath channels. The same transmitted RF signal on different paths between the transmitter and receiver may be referred to as a “multipath” RF signal. As used herein, an RF signal may also be referred to as a “wireless signal” or simply a “signal” where it is clear from the context that the term “signal” refers to a wireless signal or an RF signal. 
     According to various aspects,  FIG.  1    illustrates an exemplary wireless communications system  100 . The wireless communications system  100  (which may also be referred to as a wireless wide area network (WWAN)) may include various base stations  102  and various UEs  104 . The base stations  102  may include macro cell base stations (high power cellular base stations) and/or small cell base stations (low power cellular base stations). In an aspect, the macro cell base station may include eNBs and/or ng-eNBs where the wireless communications system  100  corresponds to an LTE network, or gNBs where the wireless communications system  100  corresponds to a NR network, or a combination of both, and the small cell base stations may include femtocells, picocells, microcells, etc. 
     The base stations  102  may collectively form a RAN and interface with a core network  170  (e.g., an evolved packet core (EPC) or a 5G core (5GC)) through backhaul links  122 , and through the core network  170  to one or more location servers  172  (which may be part of core network  170  or may be external to core network  170 ). In addition to other functions, the base stations  102  may perform functions that relate to one or more of transferring user data, radio channel ciphering and deciphering, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection setup and release, load balancing, distribution for non-access stratum (NAS) messages, NAS node selection, synchronization, RAN sharing, multimedia broadcast multicast service (MBMS), subscriber and equipment trace, RAN information management (RIM), paging, positioning, and delivery of warning messages. The base stations  102  may communicate with each other directly or indirectly (e.g., through the EPC/5GC) over backhaul links  134 , which may be wired or wireless. 
     The base stations  102  may wirelessly communicate with the UEs  104 . Each of the base stations  102  may provide communication coverage for a respective geographic coverage area  110 . In an aspect, one or more cells may be supported by a base station  102  in each geographic coverage area  110 . A “cell” is a logical communication entity used for communication with a base station (e.g., over some frequency resource, referred to as a carrier frequency, component carrier, carrier, band, or the like), and may be associated with an identifier (e.g., a physical cell identifier (PCI), a virtual cell identifier (VCI), a cell global identifier (CGI)) for distinguishing cells operating via the same or a different carrier frequency. In some cases, different cells may be configured according to different protocol types (e.g., machine-type communication (MTC), narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB), or others) that may provide access for different types of UEs. Because a cell is supported by a specific base station, the term “cell” may refer to either or both of the logical communication entity and the base station that supports it, depending on the context. In addition, because a TRP is typically the physical transmission point of a cell, the terms “cell” and “TRP” may be used interchangeably. In some cases, the term “cell” may also refer to a geographic coverage area of a base station (e.g., a sector), insofar as a carrier frequency can be detected and used for communication within some portion of geographic coverage areas  110 . 
     While neighboring macro cell base station  102  geographic coverage areas  110  may partially overlap (e.g., in a handover region), some of the geographic coverage areas  110  may be substantially overlapped by a larger geographic coverage area  110 . For example, a small cell base station  102 ′ may have a geographic coverage area  110 ′ that substantially overlaps with the geographic coverage area  110  of one or more macro cell base stations  102 . A network that includes both small cell and macro cell base stations may be known as a heterogeneous network. A heterogeneous network may also include home eNBs (HeNBs), which may provide service to a restricted group known as a closed subscriber group (CSG). 
     The communication links  120  between the base stations  102  and the UEs  104  may include uplink (also referred to as reverse link) transmissions from a UE  104  to a base station  102  and/or downlink (also referred to as forward link) transmissions from a base station  102  to a UE  104 . The communication links  120  may use MIMO antenna technology, including spatial multiplexing, beamforming, and/or transmit diversity. The communication links  120  may be through one or more carrier frequencies. Allocation of carriers may be asymmetric with respect to downlink and uplink (e.g., more or less carriers may be allocated for downlink than for uplink). 
     The wireless communications system  100  may further include a wireless local area network (WLAN) access point (AP)  150  in communication with WLAN stations (STAs)  152  via communication links  154  in an unlicensed frequency spectrum (e.g., 5 GHz). When communicating in an unlicensed frequency spectrum, the WLAN STAs  152  and/or the WLAN AP  150  may perform a clear channel assessment (CCA) or listen before talk (LBT) procedure prior to communicating in order to determine whether the channel is available. 
     The small cell base station  102 ′ may operate in a licensed and/or an unlicensed frequency spectrum. When operating in an unlicensed frequency spectrum, the small cell base station  102 ′ may employ LTE or NR technology and use the same 5 GHz unlicensed frequency spectrum as used by the WLAN AP  150 . The small cell base station  102 ′, employing LTE/5G in an unlicensed frequency spectrum, may boost coverage to and/or increase capacity of the access network. NR in unlicensed spectrum may be referred to as NR-U. LTE in an unlicensed spectrum may be referred to as LTE-U, licensed assisted access (LAA), or MulteFire. 
     The wireless communications system  100  may further include a millimeter wave (mmW) base station  180  that may operate in mmW frequencies and/or near mmW frequencies in communication with a UE  182 . Extremely high frequency (EHF) is part of the RF in the electromagnetic spectrum. EHF has a range of 30 GHz to 300 GHz and a wavelength between 1 millimeter and 10 millimeters. Radio waves in this band may be referred to as a millimeter wave. Near mmW may extend down to a frequency of 3 GHz with a wavelength of 100 millimeters. The super high frequency (SHF) band extends between 3 GHz and 30 GHz, also referred to as centimeter wave. Communications using the mmW/near mmW radio frequency band have high path loss and a relatively short range. The mmW base station  180  and the UE  182  may utilize beamforming (transmit and/or receive) over a mmW communication link  184  to compensate for the extremely high path loss and short range. Further, it will be appreciated that in alternative configurations, one or more base stations  102  may also transmit using mmW or near mmW and beamforming. Accordingly, it will be appreciated that the foregoing illustrations are merely examples and should not be construed to limit the various aspects disclosed herein. 
     Transmit beamforming is a technique for focusing an RF signal in a specific direction. Traditionally, when a network node (e.g., a base station) broadcasts an RF signal, it broadcasts the signal in all directions (omni-directionally). With transmit beamforming, the network node determines where a given target device (e.g., a UE) is located (relative to the transmitting network node) and projects a stronger downlink RF signal in that specific direction, thereby providing a faster (in terms of data rate) and stronger RF signal for the receiving device(s). To change the directionality of the RF signal when transmitting, a network node can control the phase and relative amplitude of the RF signal at each of the one or more transmitters that are broadcasting the RF signal. For example, a network node may use an array of antennas (referred to as a “phased array” or an “antenna array”) that creates a beam of RF waves that can be “steered” to point in different directions, without actually moving the antennas. Specifically, the RF current from the transmitter is fed to the individual antennas with the correct phase relationship so that the radio waves from the separate antennas add together to increase the radiation in a desired direction, while canceling to suppress radiation in undesired directions. 
     Transmit beams may be quasi-collocated, meaning that they appear to the receiver (e.g., a UE) as having the same parameters, regardless of whether or not the transmitting antennas of the network node themselves are physically collocated. In NR, there are four types of quasi-collocation (QCL) relations. Specifically, a QCL relation of a given type means that certain parameters about a second reference RF signal on a second beam can be derived from information about a source reference RF signal on a source beam. Thus, if the source reference RF signal is QCL Type A, the receiver can use the source reference RF signal to estimate the Doppler shift, Doppler spread, average delay, and delay spread of a second reference RF signal transmitted on the same channel. If the source reference RF signal is QCL Type B, the receiver can use the source reference RF signal to estimate the Doppler shift and Doppler spread of a second reference RF signal transmitted on the same channel. If the source reference RF signal is QCL Type C, the receiver can use the source reference RF signal to estimate the Doppler shift and average delay of a second reference RF signal transmitted on the same channel. If the source reference RF signal is QCL Type D, the receiver can use the source reference RF signal to estimate the spatial receive parameter of a second reference RF signal transmitted on the same channel. 
     In receive beamforming, the receiver uses a receive beam to amplify RF signals detected on a given channel. For example, the receiver can increase the gain setting and/or adjust the phase setting of an array of antennas in a particular direction to amplify (e.g., to increase the gain level of) the RF signals received from that direction. Thus, when a receiver is said to beamform in a certain direction, it means the beam gain in that direction is high relative to the beam gain along other directions, or the beam gain in that direction is the highest compared to the beam gain in that direction of all other receive beams available to the receiver. This results in a stronger received signal strength (e.g., reference signal received power (RSRP), reference signal received quality (RSRQ), signal-to-interference-plus-noise ratio (SINR), etc.) of the RF signals received from that direction. 
     Receive beams may be spatially related. A spatial relation means that parameters for a transmit beam for a second reference signal can be derived from information about a receive beam for a first reference signal. For example, a UE may use a particular receive beam to receive one or more reference downlink reference signals (e.g., positioning reference signals (PRS), navigation reference signals (NRS), tracking reference signals (TRS), phase tracking reference signal (PTRS), cell-specific reference signals (CRS), channel state information reference signals (CSI-RS), primary synchronization signals (PSS), secondary synchronization signals (SSS), synchronization signal blocks (SSBs), etc.) from a base station. The UE can then form a transmit beam for sending one or more uplink reference signals (e.g., uplink positioning reference signals (UL-PRS), sounding reference signal (SRS), demodulation reference signals (DMRS), etc.) to that base station based on the parameters of the receive beam. 
     Note that a “downlink” beam may be either a transmit beam or a receive beam, depending on the entity forming it. For example, if a base station is forming the downlink beam to transmit a reference signal to a UE, the downlink beam is a transmit beam. If the UE is forming the downlink beam, however, it is a receive beam to receive the downlink reference signal. Similarly, an “uplink” beam may be either a transmit beam or a receive beam, depending on the entity forming it. For example, if a base station is forming the uplink beam, it is an uplink receive beam, and if a UE is forming the uplink beam, it is an uplink transmit beam. 
     In 5G, the frequency spectrum in which wireless nodes (e.g., base stations  102 / 180 , UEs  104 / 182 ) operate is divided into multiple frequency ranges, FR1 (from 450 to 6000 MHz), FR2 (from 24250 to 52600 MHz), FR3 (above 52600 MHz), and FR4 (between FR1 and FR2). In a multi-carrier system, such as 5G, one of the carrier frequencies is referred to as the “primary carrier” or “anchor carrier” or “primary serving cell” or “PCell,” and the remaining carrier frequencies are referred to as “secondary carriers” or “secondary serving cells” or “SCells.” In carrier aggregation, the anchor carrier is the carrier operating on the primary frequency (e.g., FR1) utilized by a UE  104 / 182  and the cell in which the UE  104 / 182  either performs the initial radio resource control (RRC) connection establishment procedure or initiates the RRC connection re-establishment procedure. The primary carrier carries all common and UE-specific control channels, and may be a carrier in a licensed frequency (however, this is not always the case). A secondary carrier is a carrier operating on a second frequency (e.g., FR2) that may be configured once the RRC connection is established between the UE  104  and the anchor carrier and that may be used to provide additional radio resources. In some cases, the secondary carrier may be a carrier in an unlicensed frequency. The secondary carrier may contain only necessary signaling information and signals, for example, those that are UE-specific may not be present in the secondary carrier, since both primary uplink and downlink carriers are typically UE-specific. This means that different UEs  104 / 182  in a cell may have different downlink primary carriers. The same is true for the uplink primary carriers. The network is able to change the primary carrier of any UE  104 / 182  at any time. This is done, for example, to balance the load on different carriers. Because a “serving cell” (whether a PCell or an SCell) corresponds to a carrier frequency/component carrier over which some base station is communicating, the term “cell,” “serving cell,” “component carrier,” “carrier frequency,” and the like can be used interchangeably. 
     For example, still referring to  FIG.  1   , one of the frequencies utilized by the macro cell base stations  102  may be an anchor carrier (or “PCell”) and other frequencies utilized by the macro cell base stations  102  and/or the mmW base station  180  may be secondary carriers (“SCells”). The simultaneous transmission and/or reception of multiple carriers enables the UE  104 / 182  to significantly increase its data transmission and/or reception rates. For example, two 20 MHz aggregated carriers in a multi-carrier system would theoretically lead to a two-fold increase in data rate (i.e., 40 MHz), compared to that attained by a single 20 MHz carrier. 
     The wireless communications system  100  may further include one or more UEs, such as UE  190 , that connects indirectly to one or more communication networks via one or more device-to-device (D2D) peer-to-peer (P2P) links. In the example of  FIG.  1   , UE  190  has a D2D P2P link  192  with one of the UEs  104  connected to one of the base stations  102  (e.g., through which UE  190  may indirectly obtain cellular connectivity) and a D2D P2P link  194  with WLAN STA  152  connected to the WLAN AP  150  (through which UE  190  may indirectly obtain WLAN-based Internet connectivity). In an example, the D2D P2P links  192  and  194  may be supported with any well-known D2D RAT, such as LTE Direct (LTE-D), WiFi Direct (WiFi-D), Bluetooth®, and so on. 
     The wireless communications system  100  may further include a UE  164  that may communicate with a macro cell base station  102  over a communication link  120  and/or the mmW base station  180  over a mmW communication link  184 . For example, the macro cell base station  102  may support a PCell and one or more SCells for the UE  164  and the mmW base station  180  may support one or more SCells for the UE  164 . 
     According to various aspects,  FIG.  2 A  illustrates an example wireless network structure  200 . For example, a 5GC  210  (also referred to as a Next Generation Core (NGC)) can be viewed functionally as control plane functions  214  (e.g., UE registration, authentication, network access, gateway selection, etc.) and user plane functions  212 , (e.g., UE gateway function, access to data networks, IP routing, etc.) which operate cooperatively to form the core network. User plane interface (NG-U)  213  and control plane interface (NG-C)  215  connect the gNB  222  to the 5GC  210  and specifically to the control plane functions  214  and user plane functions  212 . In an additional configuration, an ng-eNB  224  may also be connected to the 5GC  210  via NG-C  215  to the control plane functions  214  and NG-U  213  to user plane functions  212 . Further, ng-eNB  224  may directly communicate with gNB  222  via a backhaul connection  223 . In some configurations, the New RAN  220  may only have one or more gNBs  222 , while other configurations include one or more of both ng-eNBs  224  and gNBs  222 . Either gNB  222  or ng-eNB  224  may communicate with UEs  204  (e.g., any of the UEs depicted in  FIG.  1   ). Another optional aspect may include location server  230 , which may be in communication with the 5GC  210  to provide location assistance for UEs  204 . The location server  230  can be implemented as a plurality of separate servers (e.g., physically separate servers, different software modules on a single server, different software modules spread across multiple physical servers, etc.), or alternately may each correspond to a single server. The location server  230  can be configured to support one or more location services for UEs  204  that can connect to the location server  230  via the core network, 5GC  210 , and/or via the Internet (not illustrated). Further, the location server  230  may be integrated into a component of the core network, or alternatively may be external to the core network. 
     According to various aspects,  FIG.  2 B  illustrates another example wireless network structure  250 . For example, a 5GC  260  can be viewed functionally as control plane functions, provided by an access and mobility management function (AMF)  264 , and user plane functions, provided by a user plane function (UPF)  262 , which operate cooperatively to form the core network (i.e., 5GC  260 ). User plane interface  263  and control plane interface  265  connect the ng-eNB  224  to the 5GC  260  and specifically to UPF  262  and AMF  264 , respectively. In an additional configuration, a gNB  222  may also be connected to the 5GC  260  via control plane interface  265  to AMF  264  and user plane interface  263  to UPF  262 . Further, ng-eNB  224  may directly communicate with gNB  222  via the backhaul connection  223 , with or without gNB direct connectivity to the 5GC  260 . In some configurations, the New RAN  220  may only have one or more gNBs  222 , while other configurations include one or more of both ng-eNBs  224  and gNBs  222 . Either gNB  222  or ng-eNB  224  may communicate with UEs  204  (e.g., any of the UEs depicted in  FIG.  1   ). The base stations of the New RAN  220  communicate with the AMF  264  over the N 2  interface and with the UPF  262  over the N 3  interface. 
     The functions of the AMF  264  include registration management, connection management, reachability management, mobility management, lawful interception, transport for session management (SM) messages between the UE  204  and a session management function (SMF)  266 , transparent proxy services for routing SM messages, access authentication and access authorization, transport for short message service (SMS) messages between the UE  204  and the short message service function (SMSF) (not shown), and security anchor functionality (SEAF). The AMF  264  also interacts with an authentication server function (AUSF) (not shown) and the UE  204 , and receives the intermediate key that was established as a result of the UE  204  authentication process. In the case of authentication based on a UMTS (universal mobile telecommunications system) subscriber identity module (USIM), the AMF  264  retrieves the security material from the AUSF. The functions of the AMF  264  also include security context management (SCM). The SCM receives a key from the SEAF that it uses to derive access-network specific keys. The functionality of the AMF  264  also includes location services management for regulatory services, transport for location services messages between the UE  204  and a location management function (LMF)  270  (which acts as a location server  230 ), transport for location services messages between the New RAN  220  and the LMF  270 , evolved packet system (EPS) bearer identifier allocation for interworking with the EPS, and UE  204  mobility event notification. In addition, the AMF  264  also supports functionalities for non-3GPP access networks. 
     Functions of the UPF  262  include acting as an anchor point for intra-/inter-RAT mobility (when applicable), acting as an external protocol data unit (PDU) session point of interconnect to a data network (not shown), providing packet routing and forwarding, packet inspection, user plane policy rule enforcement (e.g., gating, redirection, traffic steering), lawful interception (user plane collection), traffic usage reporting, quality of service (QoS) handling for the user plane (e.g., uplink/downlink rate enforcement, reflective QoS marking in the downlink), uplink traffic verification (service data flow (SDF) to QoS flow mapping), transport level packet marking in the uplink and downlink, downlink packet buffering and downlink data notification triggering, and sending and forwarding of one or more “end markers” to the source RAN node. The UPF  262  may also support transfer of location services messages over a user plane between the UE  204  and a location server, such as a secure user plane location (SUPL) location platform (SLP)  272 . 
     The functions of the SMF  266  include session management, UE Internet protocol (IP) address allocation and management, selection and control of user plane functions, configuration of traffic steering at the UPF  262  to route traffic to the proper destination, control of part of policy enforcement and QoS, and downlink data notification. The interface over which the SMF  266  communicates with the AMF  264  is referred to as the N 11  interface. 
     Another optional aspect may include an LMF  270 , which may be in communication with the 5GC  260  to provide location assistance for UEs  204 . The LMF  270  can be implemented as a plurality of separate servers (e.g., physically separate servers, different software modules on a single server, different software modules spread across multiple physical servers, etc.), or alternately may each correspond to a single server. The LMF  270  can be configured to support one or more location services for UEs  204  that can connect to the LMF  270  via the core network, 5GC  260 , and/or via the Internet (not illustrated). The SLP  272  may support similar functions to the LMF  270 , but whereas the LMF  270  may communicate with the AMF  264 , New RAN  220 , and UEs  204  over a control plane (e.g., using interfaces and protocols intended to convey signaling messages and not voice or data), the SLP  272  may communicate with UEs  204  and external clients (not shown in  FIG.  2 B ) over a user plane (e.g., using protocols intended to carry voice and/or data like the transmission control protocol (TCP) and/or IP). 
       FIGS.  3 A,  3 B, and  3 C  illustrate several exemplary components (represented by corresponding blocks) that may be incorporated into a UE  302  (which may correspond to any of the UEs described herein), a base station  304  (which may correspond to any of the base stations described herein), and a network entity  306  (which may correspond to or embody any of the network functions described herein, including the location server  230 , the LMF  270 , and the SLP  272 ) to support the file transmission operations as taught herein. It will be appreciated that these components may be implemented in different types of apparatuses in different implementations (e.g., in an ASIC, in a system-on-chip (SoC), etc.). The illustrated components may also be incorporated into other apparatuses in a communication system. For example, other apparatuses in a system may include components similar to those described to provide similar functionality. Also, a given apparatus may contain one or more of the components. For example, an apparatus may include multiple transceiver components that enable the apparatus to operate on multiple carriers and/or communicate via different technologies. 
     The UE  302  and the base station  304  each include wireless wide area network (WWAN) transceiver  310  and  350 , respectively, configured to communicate via one or more wireless communication networks (not shown), such as an NR network, an LTE network, a GSM network, and/or the like. The WWAN transceivers  310  and  350  may be connected to one or more antennas  316  and  356 , respectively, for communicating with other network nodes, such as other UEs, access points, base stations (e.g., ng-eNBs, gNBs), etc., via at least one designated RAT (e.g., NR, LTE, GSM, etc.) over a wireless communication medium of interest (e.g., some set of time/frequency resources in a particular frequency spectrum). The WWAN transceivers  310  and  350  may be variously configured for transmitting and encoding signals  318  and  358  (e.g., messages, indications, information, and so on), respectively, and, conversely, for receiving and decoding signals  318  and  358  (e.g., messages, indications, information, pilots, and so on), respectively, in accordance with the designated RAT. Specifically, the WWAN transceivers  310  and  350  include one or more transmitters  314  and  354 , respectively, for transmitting and encoding signals  318  and  358 , respectively, and one or more receivers  312  and  352 , respectively, for receiving and decoding signals  318  and  358 , respectively. 
     The UE  302  and the base station  304  also include, at least in some cases, wireless local area network (WLAN) transceivers  320  and  360 , respectively. The WLAN transceivers  320  and  360  may be connected to one or more antennas  326  and  366 , respectively, for communicating with other network nodes, such as other UEs, access points, base stations, etc., via at least one designated RAT (e.g., WiFi, LTE-D, Bluetooth®, etc.) over a wireless communication medium of interest. The WLAN transceivers  320  and  360  may be variously configured for transmitting and encoding signals  328  and  368  (e.g., messages, indications, information, and so on), respectively, and, conversely, for receiving and decoding signals  328  and  368  (e.g., messages, indications, information, pilots, and so on), respectively, in accordance with the designated RAT. Specifically, the transceivers  320  and  360  include one or more transmitters  324  and  364 , respectively, for transmitting and encoding signals  328  and  368 , respectively, and one or more receivers  322  and  362 , respectively, for receiving and decoding signals  328  and  368 , respectively. 
     Transceiver circuitry including at least one transmitter and at least one receiver may comprise an integrated device (e.g., embodied as a transmitter circuit and a receiver circuit of a single communication device) in some implementations, may comprise a separate transmitter device and a separate receiver device in some implementations, or may be embodied in other ways in other implementations. In an aspect, a transmitter may include or be coupled to a plurality of antennas (e.g., antennas  316 ,  326 ,  356 ,  366 ), such as an antenna array, that permits the respective apparatus to perform transmit “beamforming,” as described herein. Similarly, a receiver may include or be coupled to a plurality of antennas (e.g., antennas  316 ,  326 ,  356 ,  366 ), such as an antenna array, that permits the respective apparatus to perform receive beamforming, as described herein. In an aspect, the transmitter and receiver may share the same plurality of antennas (e.g., antennas  316 ,  326 ,  356 ,  366 ), such that the respective apparatus can only receive or transmit at a given time, not both at the same time. A wireless communication device (e.g., one or both of the transceivers  310  and  320  and/or  350  and  360 ) of the UE  302  and/or the base station  304  may also comprise a network listen module (NLM) or the like for performing various measurements. 
     The UE  302  and the base station  304  also include, at least in some cases, satellite positioning systems (SPS) receivers  330  and  370 . The SPS receivers  330  and  370  may be connected to one or more antennas  336  and  376 , respectively, for receiving SPS signals  338  and  378 , respectively, such as global positioning system (GPS) signals, global navigation satellite system (GLONASS) signals, Galileo signals, Beidou signals, Indian Regional Navigation Satellite System (NAVIC), Quasi-Zenith Satellite System (QZSS), etc. The SPS receivers  330  and  370  may comprise any suitable hardware and/or software for receiving and processing SPS signals  338  and  378 , respectively. The SPS receivers  330  and  370  request information and operations as appropriate from the other systems, and performs calculations necessary to determine positions of the UE  302  and the base station  304  using measurements obtained by any suitable SPS algorithm. 
     The base station  304  and the network entity  306  each include at least one network interfaces  380  and  390  for communicating with other network entities. For example, the network interfaces  380  and  390  (e.g., one or more network access ports) may be configured to communicate with one or more network entities via a wire-based or wireless backhaul connection. In some aspects, the network interfaces  380  and  390  may be implemented as transceivers configured to support wire-based or wireless signal communication. This communication may involve, for example, sending and receiving messages, parameters, and/or other types of information. 
     The UE  302 , the base station  304 , and the network entity  306  also include other components that may be used in conjunction with the operations as disclosed herein. The UE  302  includes processor circuitry implementing a processing system  332  for providing functionality relating to, for example, positioning operations, and for providing other processing functionality. The base station  304  includes a processing system  384  for providing functionality relating to, for example, positioning operations as disclosed herein, and for providing other processing functionality. The network entity  306  includes a processing system  394  for providing functionality relating to, for example, positioning operations as disclosed herein, and for providing other processing functionality. In an aspect, the processing systems  332 ,  384 , and  394  may include, for example, one or more general purpose processors, multi-core processors, ASICs, digital signal processors (DSPs), field programmable gate arrays (FPGA), or other programmable logic devices or processing circuitry. 
     The UE  302 , the base station  304 , and the network entity  306  include memory circuitry implementing memory components  340 ,  386 , and  396  (e.g., each including a memory device), respectively, for maintaining information (e.g., information indicative of reserved resources, thresholds, parameters, and so on). In some cases, the UE  302 , the base station  304 , and the network entity  306  may include positioning components  342 ,  388 , and  398 , respectively. The positioning components  342 ,  388 , and  398  may be hardware circuits that are part of or coupled to the processing systems  332 ,  384 , and  394 , respectively, that, when executed, cause the UE  302 , the base station  304 , and the network entity  306  to perform the functionality described herein. In other aspects, the positioning components  342 ,  388 , and  398  may be external to the processing systems  332 ,  384 , and  394  (e.g., part of a modem processing system, integrated with another processing system, etc.). Alternatively, the positioning components  342 ,  388 , and  398  may be memory modules (as shown in  FIGS.  3 A-C ) stored in the memory components  340 ,  386 , and  396 , respectively, that, when executed by the processing systems  332 ,  384 , and  394  (or a modem processing system, another processing system, etc.), cause the UE  302 , the base station  304 , and the network entity  306  to perform the functionality described herein. 
     The UE  302  may include one or more sensors  344  coupled to the processing system  332  to provide movement and/or orientation information that is independent of motion data derived from signals received by the WWAN transceiver  310 , the WLAN transceiver  320 , and/or the SPS receiver  330 . By way of example, the sensor(s)  344  may include an accelerometer (e.g., a micro-electrical mechanical systems (MEMS) device), a gyroscope, a geomagnetic sensor (e.g., a compass), an altimeter (e.g., a barometric pressure altimeter), and/or any other type of movement detection sensor. Moreover, the sensor(s)  344  may include a plurality of different types of devices and combine their outputs in order to provide motion information. For example, the sensor(s)  344  may use a combination of a multi-axis accelerometer and orientation sensors to provide the ability to compute positions in 2D and/or 3D coordinate systems. 
     In addition, the UE  302  includes a user interface  346  for providing indications (e.g., audible and/or visual indications) to a user and/or for receiving user input (e.g., upon user actuation of a sensing device such a keypad, a touch screen, a microphone, and so on). Although not shown, the base station  304  and the network entity  306  may also include user interfaces. 
     Referring to the processing system  384  in more detail, in the downlink, IP packets from the network entity  306  may be provided to the processing system  384 . The processing system  384  may implement functionality for an RRC layer, a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, and a medium access control (MAC) layer. The processing system  384  may provide RRC layer functionality associated with broadcasting of system information (e.g., master information block (MIB), system information blocks (SIBs)), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter-RAT mobility, and measurement configuration for UE measurement reporting; PDCP layer functionality associated with header compression/decompression, security (ciphering, deciphering, integrity protection, integrity verification), and handover support functions; RLC layer functionality associated with the transfer of upper layer packet data units (PDUs), error correction through automatic repeat request (ARQ), concatenation, segmentation, and reassembly of RLC service data units (SDUs), re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, scheduling information reporting, error correction, priority handling, and logical channel prioritization. 
     The transmitter  354  and the receiver  352  may implement Layer-1 functionality associated with various signal processing functions. Layer-1, which includes a physical (PHY) layer, may include error detection on the transport channels, forward error correction (FEC) coding/decoding of the transport channels, interleaving, rate matching, mapping onto physical channels, modulation/demodulation of physical channels, and MIMO antenna processing. The transmitter  354  handles mapping to signal constellations based on various modulation schemes (e.g., binary phase-shift keying (BPSK), quadrature phase-shift keying (QPSK), M-phase-shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM)). The coded and modulated symbols may then be split into parallel streams. Each stream may then be mapped to an orthogonal frequency division multiplexing (OFDM) subcarrier, multiplexed with a reference signal (e.g., pilot) in the time and/or frequency domain, and then combined together using an inverse fast Fourier transform (IFFT) to produce a physical channel carrying a time domain OFDM symbol stream. The OFDM symbol stream is spatially precoded to produce multiple spatial streams. Channel estimates from a channel estimator may be used to determine the coding and modulation scheme, as well as for spatial processing. The channel estimate may be derived from a reference signal and/or channel condition feedback transmitted by the UE  302 . Each spatial stream may then be provided to one or more different antennas  356 . The transmitter  354  may modulate an RF carrier with a respective spatial stream for transmission. 
     At the UE  302 , the receiver  312  receives a signal through its respective antenna(s)  316 . The receiver  312  recovers information modulated onto an RF carrier and provides the information to the processing system  332 . The transmitter  314  and the receiver  312  implement Layer-1 functionality associated with various signal processing functions. The receiver  312  may perform spatial processing on the information to recover any spatial streams destined for the UE  302 . If multiple spatial streams are destined for the UE  302 , they may be combined by the receiver  312  into a single OFDM symbol stream. The receiver  312  then converts the OFDM symbol stream from the time-domain to the frequency domain using a fast Fourier transform (FFT). The frequency domain signal comprises a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, and the reference signal, are recovered and demodulated by determining the most likely signal constellation points transmitted by the base station  304 . These soft decisions may be based on channel estimates computed by a channel estimator. The soft decisions are then decoded and de-interleaved to recover the data and control signals that were originally transmitted by the base station  304  on the physical channel. The data and control signals are then provided to the processing system  332 , which implements Layer-3 and Layer-2 functionality. 
     In the uplink, the processing system  332  provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, and control signal processing to recover IP packets from the core network. The processing system  332  is also responsible for error detection. 
     Similar to the functionality described in connection with the downlink transmission by the base station  304 , the processing system  332  provides RRC layer functionality associated with system information (e.g., MIB, SIBs) acquisition, RRC connections, and measurement reporting; PDCP layer functionality associated with header compression/decompression, and security (ciphering, deciphering, integrity protection, integrity verification); RLC layer functionality associated with the transfer of upper layer PDUs, error correction through ARQ, concatenation, segmentation, and reassembly of RLC SDUs, re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto transport blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through hybrid automatic repeat request (HARQ), priority handling, and logical channel prioritization. 
     Channel estimates derived by the channel estimator from a reference signal or feedback transmitted by the base station  304  may be used by the transmitter  314  to select the appropriate coding and modulation schemes, and to facilitate spatial processing. The spatial streams generated by the transmitter  314  may be provided to different antenna(s)  316 . The transmitter  314  may modulate an RF carrier with a respective spatial stream for transmission. 
     The uplink transmission is processed at the base station  304  in a manner similar to that described in connection with the receiver function at the UE  302 . The receiver  352  receives a signal through its respective antenna(s)  356 . The receiver  352  recovers information modulated onto an RF carrier and provides the information to the processing system  384 . 
     In the uplink, the processing system  384  provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover IP packets from the UE  302 . IP packets from the processing system  384  may be provided to the core network. The processing system  384  is also responsible for error detection. 
     For convenience, the UE  302 , the base station  304 , and/or the network entity  306  are shown in  FIGS.  3 A-C  as including various components that may be configured according to the various examples described herein. It will be appreciated, however, that the illustrated blocks may have different functionality in different designs. 
     The various components of the UE  302 , the base station  304 , and the network entity  306  may communicate with each other over data buses  334 ,  382 , and  392 , respectively. The components of  FIGS.  3 A-C  may be implemented in various ways. In some implementations, the components of  FIGS.  3 A-C  may be implemented in one or more circuits such as, for example, one or more processors and/or one or more ASICs (which may include one or more processors). Here, each circuit may use and/or incorporate at least one memory component for storing information or executable code used by the circuit to provide this functionality. For example, some or all of the functionality represented by blocks  310  to  346  may be implemented by processor and memory component(s) of the UE  302  (e.g., by execution of appropriate code and/or by appropriate configuration of processor components). Similarly, some or all of the functionality represented by blocks  350  to  388  may be implemented by processor and memory component(s) of the base station  304  (e.g., by execution of appropriate code and/or by appropriate configuration of processor components). Also, some or all of the functionality represented by blocks  390  to  398  may be implemented by processor and memory component(s) of the network entity  306  (e.g., by execution of appropriate code and/or by appropriate configuration of processor components). For simplicity, various operations, acts, and/or functions are described herein as being performed “by a UE,” “by a base station,” “by a positioning entity,” etc. However, as will be appreciated, such operations, acts, and/or functions may actually be performed by specific components or combinations of components of the UE, base station, positioning entity, etc., such as the processing systems  332 ,  384 ,  394 , the transceivers  310 ,  320 ,  350 , and  360 , the memory components  340 ,  386 , and  396 , the positioning components  342 ,  388 , and  398 , etc. 
     Various frame structures may be used to support downlink and uplink transmissions between network nodes (e.g., base stations and UEs).  FIG.  4 A  is a diagram  400  illustrating an example of a downlink frame structure, according to aspects of the disclosure.  FIG.  4 B  is a diagram  430  illustrating an example of channels within the downlink frame structure, according to aspects of the disclosure.  FIG.  4 C  is a diagram  550  illustrating an example of an uplink frame structure, according to aspects of the disclosure.  FIG.  4 D  is a diagram  580  illustrating an example of channels within an uplink frame structure, according to aspects of the disclosure. Other wireless communications technologies may have different frame structures and/or different channels. 
     LTE, and in some cases NR, utilizes OFDM on the downlink and single-carrier frequency division multiplexing (SC-FDM) on the uplink. Unlike LTE, however, NR has an option to use OFDM on the uplink as well. OFDM and SC-FDM partition the system bandwidth into multiple (K) orthogonal subcarriers, which are also commonly referred to as tones, bins, etc. Each subcarrier may be modulated with data. In general, modulation symbols are sent in the frequency domain with OFDM and in the time domain with SC-FDM. The spacing between adjacent subcarriers may be fixed, and the total number of subcarriers (K) may be dependent on the system bandwidth. For example, the spacing of the subcarriers may be 15 kHz and the minimum resource allocation (resource block) may be 12 subcarriers (or 180 kHz). Consequently, the nominal FFT size may be equal to 128, 256, 512, 1024, or 2048 for system bandwidth of 1.25, 2.5, 5, 10, or 20 megahertz (MHz), respectively. The system bandwidth may also be partitioned into subbands. For example, a subband may cover 1.08 MHz (i.e., 6 resource blocks), and there may be 1, 2, 4, 8, or 16 subbands for system bandwidth of 1.25, 2.5, 5, 10, or 20 MHz, respectively. 
     LTE supports a single numerology (subcarrier spacing, symbol length, etc.). In contrast, NR may support multiple numerologies (μ), for example, subcarrier spacing of 15 kHz, 30 kHz, 60 kHz, 120 kHz, and 240 kHz or greater may be available. Table 1 provided below lists some various parameters for different NR numerologies. 
     
       
         
           
               
               
               
               
               
               
               
               
             
               
                 TABLE 1 
               
               
                   
               
               
                   
                   
                   
                   
                   
                 Slot 
                 Symbol 
                 Max. nominal 
               
               
                   
                   
                 Sym- 
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                 Dura- 
                 Dura- 
                 system BW 
               
               
                   
                 scs 
                 bols/ 
                 Sub- 
                 Slots/ 
                 tion 
                 tion 
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                 Sot 
                 frame 
                 Frame 
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                 (μs) 
                 4K FFT size 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                 0 
                 15 
                 14 
                 1 
                 10 
                 1 
                 66.7 
                 50 
               
               
                 1 
                 30 
                 14 
                 2 
                 20 
                 0.5 
                 33.3 
                 100 
               
               
                 2 
                 60 
                 14 
                 4 
                 40 
                 0.25 
                 16.7 
                 100 
               
               
                 3 
                 120 
                 14 
                 8 
                 80 
                 0.125 
                 8.33 
                 400 
               
               
                 4 
                 240 
                 14 
                 16 
                 160 
                 0.0625 
                 4.17 
                 800 
               
               
                   
               
            
           
         
       
     
     In the example of  FIGS.  4 A to  4 D , a numerology of 15 kHz is used. Thus, in the time domain, a frame (e.g., 10 ms) is divided into 10 equally sized subframes of 1 ms each, and each subframe includes one time slot. In  FIGS.  4 A to  4 D , time is represented horizontally (e.g., on the X axis) with time increasing from left to right, while frequency is represented vertically (e.g., on the Y axis) with frequency increasing (or decreasing) from bottom to top. 
     A resource grid may be used to represent time slots, each time slot including one or more time-concurrent resource blocks (RBs) (also referred to as physical RBs (PRBs)) in the frequency domain. The resource grid is further divided into multiple resource elements (REs). An RE may correspond to one symbol length in the time domain and one subcarrier in the frequency domain. In the numerology of  FIGS.  4 A to  4 D , for a normal cyclic prefix, an RB may contain 12 consecutive subcarriers in the frequency domain and seven consecutive symbols in the time domain, for a total of 84 REs. For an extended cyclic prefix, an RB may contain 12 consecutive subcarriers in the frequency domain and six consecutive symbols in the time domain, for a total of 72 REs. The number of bits carried by each RE depends on the modulation scheme. 
     Some of the REs carry downlink reference (pilot) signals (DL-RS). The DL-RS may include PRS in LTE, NRS in 5G, TRS, PTRS, CRS, CSI-RS, DMRS, PSS, SSS, SSB, etc.  FIG.  4 A  illustrates exemplary locations of REs carrying PRS (labeled “R”). 
     A collection of resource elements (REs) that are used for transmission of PRS is referred to as a “PRS resource.” The collection of resource elements can span multiple PRBs in the frequency domain and ‘N’ (e.g., 1 or more) consecutive symbol(s) within a slot in the time domain. In a given OFDM symbol in the time domain, a PRS resource occupies consecutive PRBs in the frequency domain. 
     The transmission of a PRS resource within a given PRB has a particular comb size (also referred to as the “comb density”). A comb size ‘N’ represents the subcarrier spacing (or frequency/tone spacing) within each symbol of a PRS resource configuration. Specifically, for a comb size ‘N,’ PRS are transmitted in every Nth subcarrier of a symbol of a PRB. For example, for comb-4, for each of the fours symbols of the PRS resource configuration, REs corresponding to every fourth subcarrier (e.g., subcarriers 0, 4, 8) are used to transmit PRS of the PRS resource. Currently, comb sizes of comb-2, comb-4, comb-6, and comb-12 are supported for DL-PRS.  FIG.  4 A  illustrates an exemplary PRS resource configuration for comb-6 (which spans six symbols). That is, the locations of the shaded REs (labeled “R”) indicate a comb-6 PRS resource configuration. 
     A “PRS resource set” is a set of PRS resources used for the transmission of PRS signals, where each PRS resource has a PRS resource ID. In addition, the PRS resources in a PRS resource set are associated with the same TRP. A PRS resource set is identified by a PRS resource set ID and is associated with a particular TRP (identified by a cell ID). In addition, the PRS resources in a PRS resource set have the same periodicity, a common muting pattern configuration, and the same repetition factor across slots. The periodicity may have a length selected from 2 m ·{4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 160, 320, 640, 1280, 2560, 5120, 10240} slots, with μ=0, 1, 2, 3. The repetition factor may have a length selected from {1, 2, 4, 6, 8, 16, 32} slots. 
     A PRS resource ID in a PRS resource set is associated with a single beam (and/or beam ID) transmitted from a single TRP (where a TRP may transmit one or more beams). That is, each PRS resource of a PRS resource set may be transmitted on a different beam, and as such, a “PRS resource,” or simply “resource,” can also be referred to as a “beam.” Note that this does not have any implications on whether the TRPs and the beams on which PRS are transmitted are known to the UE. 
     A “PRS instance” or “PRS occasion” is one instance of a periodically repeated time window (e.g., a group of one or more consecutive slots) where PRS are expected to be transmitted. A PRS occasion may also be referred to as a “PRS positioning occasion,” a “PRS positioning instance”, a “positioning occasion,” “a positioning instance,” or simply an “occasion” or “instance.” 
       FIG.  4 B  illustrates an example of various channels within a downlink slot of a radio frame. In NR, the channel bandwidth, or system bandwidth, is divided into multiple bandwidth parts (BWPs). A BWP is a contiguous set of PRBs selected from a contiguous subset of the common RBs for a given numerology on a given carrier. Generally, a maximum of four BWPs can be specified in the downlink and uplink. That is, a UE can be configured with up to four BWPs on the downlink, and up to four BWPs on the uplink. Only one BWP (uplink or downlink) may be active at a given time, meaning the UE may only receive or transmit over one BWP at a time. On the downlink, the bandwidth of each BWP should be equal to or greater than the bandwidth of the SSB, but it may or may not contain the SSB. 
     Referring to  FIG.  4 B , a primary synchronization signal (PSS) is used by a UE to determine subframe/symbol timing and a physical layer identity. A secondary synchronization signal (SSS) is used by a UE to determine a physical layer cell identity group number and radio frame timing. Based on the physical layer identity and the physical layer cell identity group number, the UE can determine a PCI. Based on the PCI, the UE can determine the locations of the aforementioned DL-RS. The physical broadcast channel (PBCH), which carries an MIB, may be logically grouped with the PSS and SSS to form an SSB (also referred to as an SS/PBCH). The MIB provides a number of RBs in the downlink system bandwidth and a system frame number (SFN). The physical downlink shared channel (PDSCH) carries user data, broadcast system information not transmitted through the PBCH, such as system information blocks (SIBs), and paging messages. 
     The physical downlink control channel (PDCCH) carries downlink control information (DCI) within one or more control channel elements (CCEs), each CCE including one or more RE group (REG) bundles (which may span multiple symbols in the time domain), each REG bundle including one or more REGs, each REG corresponding to 12 resource elements (one resource block) in the frequency domain and one OFDM symbol in the time domain. The set of physical resources used to carry the PDCCH/DCI is referred to in NR as the control resource set (CORESET). In NR, a PDCCH is confined to a single CORESET and is transmitted with its own DMRS. This enables UE-specific beamforming for the PDCCH. 
     In the example of  FIG.  4 B , there is one CORESET per BWP, and the CORESET spans three symbols in the time domain. Unlike LTE control channels, which occupy the entire system bandwidth, in NR, PDCCH channels are localized to a specific region in the frequency domain (i.e., a CORESET). Thus, the frequency component of the PDCCH shown in  FIG.  4 B  is illustrated as less than a single BWP in the frequency domain. Note that although the illustrated CORESET is contiguous in the frequency domain, it need not be. In addition, the CORESET may span less than three symbols in the time domain. 
     The DCI within the PDCCH carries information about uplink resource allocation (persistent and non-persistent) and descriptions about downlink data transmitted to the UE. Multiple (e.g., up to eight) DCIs can be configured in the PDCCH, and these DCIs can have one of multiple formats. For example, there are different DCI formats for uplink scheduling, for non-MIMO downlink scheduling, for MIMO downlink scheduling, and for uplink power control. A PDCCH may be transported by 1, 2, 4, 8, or 16 CCEs in order to accommodate different DCI payload sizes or coding rates. 
     As illustrated in  FIG.  4 C , some of the REs carry DMRS for channel estimation at the base station. The UE may additionally transmit SRS in, for example, the last symbol of a subframe. The SRS may have a comb structure, and a UE may transmit SRS on one of the combs. The comb structure (also referred to as the “comb size”) indicates the number of subcarriers in each symbol period carrying a reference signal (here, SRS). For example, a comb size of comb-4 means that every fourth subcarrier of a given symbol carries the reference signal, whereas a comb size of comb-2 means that every second subcarrier of a given symbol carries the reference signal. In the example of  FIG.  4 C , the illustrated SRS are both comb-2. The SRS may be used by a base station to obtain the channel state information (CSI) for each UE. CSI describes how an RF signal propagates from the UE to the base station and represents the combined effect of scattering, fading, and power decay with distance. The system uses the SRS for resource scheduling, link adaptation, massive MIMO, beam management, etc. 
       FIG.  4 D  illustrates an example of various channels within an uplink subframe of a frame, according to aspects of the disclosure. A random access channel (RACH), also referred to as a physical random access channel (PRACH), may be within one or more subframes within a frame based on the PRACH configuration. The PRACH may include six consecutive RB pairs within a subframe. The PRACH allows the UE to perform initial system access and achieve uplink synchronization. A physical uplink control channel (PUCCH) may be located on edges of the uplink system bandwidth. The PUCCH carries uplink control information (UCI), such as scheduling requests, CSI reports, a channel quality indicator (CQI), a precoding matrix indicator (PMI), a rank indicator (RI), and HARQ ACK/NACK feedback. The physical uplink shared channel (PUSCH) carries data, and may additionally be used to carry a buffer status report (BSR), a power headroom report (PHR), and/or UCI. 
     A collection of resource elements that are used for transmission of SRS is referred to as an “SRS resource,” and may be identified by the parameter SRS-ResourceId. The collection of resource elements can span multiple PRBs in the frequency domain and N (e.g., one or more) consecutive symbol(s) within a slot in the time domain. In a given OFDM symbol, an SRS resource occupies consecutive PRBs. An “SRS resource set” is a set of SRS resources used for the transmission of SRS signals, and is identified by an SRS resource set ID (SRS-ResourceSetId). 
     Generally, a UE transmits SRS to enable the receiving base station (either the serving base station or a neighboring base station) to measure the channel quality between the UE and the base station. However, SRS can also be used as uplink positioning reference signals for uplink positioning procedures, such as uplink time-difference of arrival (UL-TDOA), multi-round-trip-time (multi-RTT), downlink angle-of-arrival (DL-AoA), etc. 
     Several enhancements over the previous definition of SRS have been proposed for SRS-for-positioning (also referred to as “UL-PRS”), such as a new staggered pattern within an SRS resource (except for single-symbol/comb-2), a new comb type for SRS, new sequences for SRS, a higher number of SRS resource sets per component carrier, and a higher number of SRS resources per component carrier. In addition, the parameters SpatialRelationInfo and PathLossReference are to be configured based on a downlink reference signal or SSB from a neighboring TRP. Further still, one SRS resource may be transmitted outside the active BWP, and one SRS resource may span across multiple component carriers. Also, SRS may be configured in RRC connected state and only transmitted within an active BWP. Further, there may be no frequency hopping, no repetition factor, a single antenna port, and new lengths for SRS (e.g., 8 and 12 symbols). There may also be open-loop power control and not closed-loop power control, and comb-8 (i.e., an SRS transmitted every eighth subcarrier in the same symbol) may be used. Lastly, the UE may transmit through the same transmit beam from multiple SRS resources for UL-AoA. All of these are features that are additional to the current SRS framework, which is configured through RRC higher layer signaling (and potentially triggered or activated through MAC control element (CE) or DCI). 
     Note that the terms “positioning reference signal” and “PRS” may sometimes refer to specific reference signals that are used for positioning in LTE systems. However, as used herein, unless otherwise indicated, the terms “positioning reference signal” and “PRS” refer to any type of reference signal that can be used for positioning, such as but not limited to, PRS in LTE, NRS in 5G, TRS, PTRS, CRS, CSI-RS, DMRS, PSS, SSS, SSB, SRS, UL-PRS, etc. In addition, the terms “positioning reference signal” and “PRS” refer to downlink or uplink positioning reference signals, unless otherwise indicated. A downlink positioning reference signal may be referred to as a “DL-PRS,” and an uplink positioning reference signal (e.g., an SRS-for-positioning, PTRS) may be referred to as an “UL-PRS.” In addition, for signals that may be transmitted in both the uplink and downlink (e.g., DMRS, PTRS), the signals may be prepended with “UL” or “DL” to distinguish the direction. For example, “UL-DMRS” may be differentiated from “DL-DMRS.” 
     The following parameters are used to configure DL-PRS resources and DL-PRS resource sets. The parameter “DL-PRS-Periodicity” defines the DL-PRS resource periodicity and takes the values of T per   PRS  ∈ {4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 160, 320, 640, 1280, 2560, 5120, 10240, 20480}, where the value 20480 is not supported for μ=0. All of the DL-PRS resources within one resource set are configured with the same periodicity. The parameter “DL-PRS-ResourceRepetitionFactor” defines how many times each DL-PRS resource is repeated for a single instance of the DL-PRS resource set and takes the values of T rep   PRS  ∈ {1,2,4,6,8,16,32}. All of the DL-PRS resources within one resource set have the same “ResourceRepetitionFactor.” The parameter “DL-PRS-ResourceTimeGap” defines the offset in number of slots between two repeated instances of a DL-PRS resource with the same DL-PRS-ResourceID within a single instance of the DL-PRS resource set, and takes the values of T gap   PRS  ∈{1,2,4,8,16,32}. The UE only expects to be configured with the “DL-PRS-ResourceTimeGap” if the “DL-PRS-ResourceRepetitionFactor” is configured with a value greater than one. The time duration spanned by one instance of a “DL-PRS-ResourceSet” is not expected to exceed the configured value of “DL-PRS-Periodicity.” All of the DL-PRS resources within one resource set have the same “DL-PRS-ResourceTimeGap.” The parameter “DL-PRS-SFNO-Offset” defines the time offset of the SFN  0  slot 0 for the transmitting cell with respect to SFN  0  slot 0. The parameter “DL-PRS-ResourceSetSlotOffset” defines the slot offset with respect to SFN  0  slot 0 and takes values T offset   PRS  ∈ {0,1, . . . , T per   PRS −1}. 
     A PRS resource is defined by the following parameters. The parameter “DL-PRS-ResourceList” determines the DL-PRS resources that are contained within one DL-PRS resource set. The parameter “DL-PRS-ResourceId” identifies a specific DL-PRS resource. All DL-PRS resource identifiers are locally defined within a DL-PRS resource set. The parameter “DL-PRS-SequenceId” is used to initialize the c init  value used in a pseudo-random generator for generation of DL-PRS sequences for a given DL-PRS resource. The parameter “DL-PRS-ReOffset” defines the starting RE offset of the first symbol within a DL-PRS resource in the frequency domain. The relative RE offsets of the remaining symbols within a DL-PRS resource are defined based on the initial offset and one or more rules. The parameter “DL-PRS-ResourceSlotOffset” determines the starting slot of the DL-PRS resource with respect to the corresponding “DL-PRS-ResourceSetSlotOffset.” The parameter “DL-PRS-ResourceSymbolOffset” determines the starting symbol of the DL-PRS resource within the starting slot. The parameter “DL-PRS-NumSymbols” defines the number of symbols of the DL-PRS resource within a slot. The parameter “DL-PRS-QCL-Info” defines any quasi-colocation information of the DL-PRS resource with other reference signals. The DL-PRS may be configured to be ‘QCL-Type-D’ with a DL-PRS or SS/PBCH block from a serving cell or a non-serving cell. The DL-PRS may be configured to be ‘QCL-Type-C’ with an SS/PBCH block from a serving or non-serving cell. The parameter “DL-PRS-ResourceBandwidth” defines the number of resource blocks configured for PRS transmission. The parameter has a granularity of four PRBs with a minimum of 24 PRBs and a maximum of 272 PRBs. All DL-PRS resources within a DL-PRS resource set have the same value of “DL-PRS-ResourceBandwidth.” The parameter “DL-PRS-StartPRB” defines the starting PRB index of the DL-PRS resource with respect to reference Point A. The starting PRB index has a granularity of one PRB with a minimum value of zero and a maximum value of 2176 PRBs. 
       FIG.  5    is a diagram of an exemplary PRS configuration  500  for the PRS transmissions of a given base station, according to aspects of the disclosure. In  FIG.  5   , time is represented horizontally, increasing from left to right. Each long rectangle represents a slot and each short (shaded) rectangle represents an OFDM symbol. The PRS configuration  500  identifies the PRS resources  512  and  514  of a PRS resource set  510  during which the base station transmits PRS. The PRS resource set  510  has an occasion length N PRS  of two (2) slots and a periodicity of T PRS  (e.g., 160 subframes or 160 ms). As such, both the PRS resources  512  and  514  are two consecutive slots in length and repeat every T PRS  subframes, starting from the slot in which the first symbol of the respective PRS resource occurs. 
     In the example of  FIG.  5   , the PRS resource set  510  includes two PRS resources, a first PRS resource  512  (labeled “PRS resource  1 ” in  FIG.  5   ) and a second PRS resource  514  (labeled “PRS resource  2 ” in  FIG.  5   ). The PRS resource  512  and the PRS resource  514  may be transmitted on separate beams of the same base station. The PRS resource  512  has a symbol length N symb  of two (2) symbols, and the PRS resource  514  has a symbol length N symb  of four (4) symbols. 
     Each instance of the PRS resource set  510 , illustrated as instances  520   a ,  520   b , and  520   c , includes an occasion of length ‘2’ (i.e., Np PRS s=2) for each PRS resource  512 ,  514  of the PRS resource set. The PRS resources  512  and  514  are repeated every T PRS  subframes up to the muting sequence periodicity T REP . As such, a bitmap of length T REP  would be needed to indicate which occasions of instances  520   a ,  520   b , and  520   c  are muted. 
     PRS, and other types of positioning reference signals, are used for a number of cellular network-based positioning technologies. Such positioning technologies include downlink-based, uplink-based, and downlink-and-uplink-based positioning methods. Downlink-based positioning methods include observed time difference of arrival (OTDOA) in LTE, downlink time difference of arrival (DL-TDOA) in NR, and downlink angle-of-departure (DL-AoD) in NR. In an OTDOA or DL-TDOA positioning procedure, a UE measures the differences between the times of arrival (ToAs) of reference signals (e.g., PRS, TRS, NRS, PTRS, CSI-RS, SSB, etc.) received from pairs of base stations, referred to as reference signal time difference (RSTD) or time difference of arrival (TDOA) measurements, and reports them to a positioning entity (e.g., the UE, a location server, a serving base station, or other network component). More specifically, the UE receives the identifiers of a reference base station (e.g., a serving base station) and multiple non-reference base stations in assistance data. The UE then measures the RSTD between the reference base station and each of the non-reference base stations. Based on the known locations of the involved base stations and the RSTD measurements, the positioning entity can estimate the UE&#39;s location. For DL-AoD positioning, a base station measures the angle and other channel properties (e.g., signal strength) of the downlink transmit beam used to communicate with a UE to estimate the location of the UE. 
     Uplink-based positioning methods include uplink time difference of arrival (UL-TDOA) and uplink angle-of-arrival (UL-AoA). UL-TDOA is similar to DL-TDOA, but is based on uplink reference signals (e.g., SRS) transmitted by the UE. For UL-AoA positioning, a base station measures the angle and other channel properties (e.g., gain level) of the uplink receive beam used to communicate with a UE to estimate the location of the UE. 
     Downlink-and-uplink-based positioning methods include enhanced cell-ID (E-CID) positioning and multi-round-trip-time (RTT) positioning (also referred to as “multi-cell RTT”). In an RTT procedure, an initiator (a base station or a UE) transmits an RTT measurement signal (e.g., a PRS or SRS) to a responder (a UE or base station), which transmits an RTT response signal (e.g., an SRS or PRS) back to the initiator. The RTT response signal includes the difference between the ToA of the RTT measurement signal and the transmission time of the RTT response signal, referred to as the reception-to-transmission (Rx-Tx) measurement. The initiator calculates the difference between the transmission time of the RTT measurement signal and the ToA of the RTT response signal, referred to as the “Tx-Rx” measurement. The propagation time (also referred to as the “time of flight”) between the initiator and the responder can be calculated from the Tx-Rx and Rx-Tx measurements. Based on the propagation time and the known speed of light, the distance between the initiator and the responder can be determined. For multi-RTT positioning, a UE performs an RTT procedure with multiple base stations to enable its location to be triangulated based on the known locations of the base stations. RTT and multi-RTT methods can be combined with other positioning techniques, such as UL-AoA and DL-AoD, to improve location accuracy. 
     The E-CID positioning method is based on radio resource management (RRM) measurements. In E-CID, the UE reports the serving cell ID, the timing advance (TA), and the identifiers, estimated timing, and signal strength of detected neighbor base stations. The location of the UE is then estimated based on this information and the known locations of the base stations. 
     To assist positioning operations, a location server (e.g., location server  230 , LMF  270 , SLP  272 ) may provide assistance data to the UE. For example, the assistance data may include identifiers of the base stations (or the cells/TRPs of the base stations) from which to measure reference signals, the reference signal configuration parameters (e.g., the number of consecutive positioning subframes, periodicity of positioning subframes, muting sequence, frequency hopping sequence, reference signal identifier (ID), reference signal bandwidth, etc.), and/or other parameters applicable to the particular positioning method. Alternatively, the assistance data may originate directly from the base stations themselves (e.g., in periodically broadcasted overhead messages, etc.). in some cases, the UE may be able to detect neighbor network nodes itself without the use of assistance data. 
     A location estimate may be referred to by other names, such as a position estimate, location, position, position fix, fix, or the like. A location estimate may be geodetic and comprise coordinates (e.g., latitude, longitude, and possibly altitude) or may be civic and comprise a street address, postal address, or some other verbal description of a location. A location estimate may further be defined relative to some other known location or defined in absolute terms (e.g., using latitude, longitude, and possibly altitude). A location estimate may include an expected error or uncertainty (e.g., by including an area or volume within which the location is expected to be included with some specified or default level of confidence). 
     It has been agreed to limit the maximum number of DL-PRS resources configured to the UE across all TRPs within a defined measurement window. That is, the TRPs involved in a positioning session with a particular UE will configure PRS resources for the UE (at the direction of the location server, such location server  230 , LMF  270 , SLP  272 ) such that all of the configured PRS resources are scheduled within a given measurement window. The length (i.e., duration) of the measurement window and the maximum number of PRS resources may be a UE capability that the UE signals to the location server via, for example, LTE positioning protocol (LPP). 
     Each TRP may configure one or more PRS resource sets in each configured PRS instance (or PRS occasion), and each PRS instance may begin at some slot offset from the start of an SFN and occurs at the PRS periodicity (i.e., T PRS ). The measurement window occurs with the same periodicity as the PRS periodicity and begins at the same slot offset. The slot offset for a DL-PRS resource set may be configured to the UE using a DL-PRS resource set offset parameter. The DL-PRS resource set offset parameter (i.e., “DL-PRS-ResourceSetSlotOffset”) defines the slot offset with respect to the first slot of an SFN (i.e., slot “0”) for a TRP where the DL-PRS resource set is configured. That is, the DL-PRS resource set slot offset parameter indicates the slot in which the first DL-PRS resource of the first DL-PRS resource set of the PRS instance occurs. The DL-PRS resource set offset parameter may have a value from 0 to a maximum resource offset value parameter (which is less than the periodicity T PRS ). 
     The PRS periodicity parameter indicates the periodicity of DL-PRS resource allocations in slots configured per the DL-PRS resource set. That is, all of the DL-PRS resources of a given PRS resource set have the same periodicity. In an aspect, the value of the PRS periodicity parameter may be selected from the set {4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 160, 320, 640, 1280, 2560, 5120, 10240, 20480}. Note that a periodicity of 20480 is not supported for a subcarrier spacing (SCS) of 15 kHz. 
     A UE may also be configured with one or more SRS resource sets. An SRS resources may be defined by a resource type parameter and a periodicity and offset parameter. The resource type parameter specifies the type of SRS resources as periodic, semi-persistent, or aperiodic. The periodicity and offset parameter specifies the periodicity and offset for semi-persistent and periodic SRS resources. All values may be provided in terms of a “number of slots.” Thus, for example, a value of “sl1” corresponds to a periodicity of one slot, a value of “sl2” corresponds to a periodicity of two slots, and so on. For each periodicity, the corresponding offset is given in the number of slots. For periodicity “sl1,” for example, the offset is 0 slots. 
       FIG.  6    is a diagram  600  of DL-PRS transmissions and UL-PRS transmissions between a TRP (labelled “TRP  1 ”) and two UEs (labelled “UE  1 ” and “UE  2 ”), according to aspects of the disclosure. Each epoch illustrated in  FIG.  6    (e.g., “Epoch  0 ,” “Epoch  1 ,” etc.) corresponds to either a downlink or uplink PRS instance (PRS occasion) during which the transmitter (TRP  1 , UE  1 , or UE  2 ) transmits PRS on the PRS resources of one or more PRS resource sets. 
     At TRP  1 , the time between the start of an SFN (labelled “SFN  0 ”) and the first PRS transmission epoch (labelled “Epoch  0 ”) is specified by the DL-PRS resource set slot offset parameter “DL-PRS-ResourceSetSlotOffset.” The time between each PRS transmission epoch (e.g., “Epoch  0 ” and “Epoch  1 ”) is specified by the DL-PRS periodicity parameter “DL-PRS-Periodicity.” 
     At the first UE, i.e., UE  1 , the time between the start of the SFN (i.e., “SFN  0 ”) and the first SRS transmission epoch (“Epoch  1 ”) is specified by the uplink SRS slot offset parameter “UL-SRS-SlotOffset.” The time between each SRS transmission epoch (e.g., “Epoch  1 ” and “Epoch  3 ”) is specified by the uplink SRS periodicity parameter “UL-SRS-Periodicity.” The time between each SRS transmission epoch is also referred to as the measurement periodicity. 
     At the second UE, i.e., UE  2 , the time between the start of the SFN (i.e., “SFN  0 ”) and the first SRS transmission epoch (“Epoch  0 ”) is specified by the uplink SRS slot offset parameter “UL-SRS-SlotOffset.” The time between each SRS transmission epoch (e.g., “Epoch  0 ” and “Epoch  2 ”) is specified by the uplink SRS periodicity parameter “UL-SRS-Periodicity.” The time between each SRS transmission epoch is also referred to as the measurement periodicity. 
     In the example of  FIG.  6   , the TRP  1  can support multiple UEs (UE  1  and UE  2 ) using a time division multiplexing (TDM) approach. That is, as shown, UE  1  transmits SRS at “Epoch  1 ” and “Epoch  3 ,” and UE  2  transmits SRS at “Epoch  0 ” and “Epoch  2 .” An epoch pair, such as Epoch  3  at TRP  1  and Epoch  3  at UE  1 , form an RTT pair (i.e., an RTT measurement signal and an RTT response signal). 
     Note that the maximum number of epochs per SFN (“N”) is based on the QoS of the location estimate, with more epochs resulting in higher positioning accuracy. 
     Ideally, all measurements that go into generating a location fix should be made concurrently. If measurements from different points in time are used for generating a location fix, UE motion, as well as changes to UE and base station clocks (referred to as “clock drift”), can result in measurement errors that ultimately could produce location errors. For example, travel at a highway speed of 30 meters per second (m/s) could result in a 30 meter (m) (i.e., 1 s*30 m/s=30 m) measurement error if two measurements were made 1 second apart. Similarly, a 10 part-per-billion UE clock drift could produce a 10 nanosecond (ns) (i.e., 1 s*10 ns/s=10 ns), approximately 3 m, measurement error for two measurements taken one second apart. With the stricter 3 m to 10 m accuracy targets for commercial use cases in NR, it is important that controllable error sources (unlike, e.g., multipath) are minimized. 
     With regard to multi-cell RTT, it is beneficial to conduct and associate as close in time as possible the Rx-Tx offset measurements produced by the UE with the Tx-Rx offset measurements produced by the corresponding TRPs (where the TRPs transmit the RTT measurement signals and the UE transmits the RTT response signals). Referring back to  FIG.  6   , this figure shows an example of an RTT pair where the DL-PRS transmission from TRP  1  and the SRS transmission from UE  1  are scheduled close in time, that is, at Epoch  5  (the reporting/positioning periodicity). 
     Continuing the example in  FIG.  6   , DL-PRS transmission is scheduled in various instances (epochs) according to the parameters “DL-PRS-ResourceSetSlotOffset” and “DL-PRS-Periodicity.” Similarly, SRS can be scheduled in instances (epochs) according to the parameters “SRS-Slot-Offset” and “SRS-Periodicity.” However, keeping with the on-demand nature of NR, there may be a start instance that specifies the first time during a session that SRS will be transmitted by a given UE (e.g., UE  1  or UE  2 ). The start of SRS transmission for positioning may, for example, be given by an SRS activation command. Likewise, a session may be limited in time by a given QoS or by the transmission of an SRS deactivation command. 
     For simplicity, the SRS instances (epochs) are numbered according to the closest DL-PRS instance (epoch). Note that a corresponding SRS instance can appear before or after the DL-PRS instance in an RTT pair. In  FIG.  6   , this is referred to as the DL-to-UL offset. Furthermore, different UEs may utilize different sets of SRS instances. The large-scale (inter-instance) and small-scale (intra-instance) TDM provides opportunities to support more UEs while minimizing signal congestion/interference on the radio link and reducing peak processing load requirements on the base stations (e.g., gNBs). 
     Currently, as noted above, all DL-PRS resources configured to the UE across all TRPs are scheduled within a measurement window. The present disclosure proposes to configure, for a given UE involved in a positioning session (e.g., multi-RTT), all DL-PRS resources across all involved TRPs and all UL-PRS (or SRS) resources to be within the same measurement/transmission window. In that way, the UE expects the “SRS-Slot-offset” and “SRS-Periodicity” parameters to be configured in an SRS-for-positioning resource such that any SRS transmission is within [−X, X] ms of at least one DL-PRS resource from each of the TRPs. For example, X may be 25 ms. Such an RS configuration may enable sufficiently close measurements in time at both the UE and TRPs. 
     In an aspect, a limit on the maximum number of UL-PRS resources configured to the UE for all TRPs within the measurement/transmission window may be defined. This limit can be signalled by the UE (e.g., to the location server over LPP) as a UE capability. In an aspect, the UE may report a different maximum length based on the frequency range (e.g., FR1, Fr2) in which the UE is operating, or the frequency band in which the UE is operating, etc. 
       FIG.  7    is a diagram  700  of a common measurement/transmission window  710  during which both DL-PRS resources  720  and UL-PRS resources  730  are scheduled for a given UE, according to aspects of the disclosure. In the example of  FIG.  7   , the measurement/transmission window  710  is 16 ms in length and occurs every 160 ms. However, as will be appreciated, this is merely an example, and numerous other configurations of the measurement/transmission window  710  are possible. 
     The DL-PRS transmissions on the DL-PRS resources  720  and the UL-PRS transmissions on the UL-PRS resources  730  within the measurement/transmission window  710  are not necessarily related to each other. That is, while the UL-PRS resources  730  may be for transmitting UL-PRS in response to DL-PRS measured on the DL-PRS resources  720 , this may not always be the case. For example, at least some of the DL-PRS resources  720  and UL-PRS resources  730  may be for different positioning sessions. For example, the DL-PRS resources  720  may be for one type of positioning session (e.g., DL-TDOA) and the UL-PRS resources  730  may be for a different type of positioning session (e.g., UL-TDOA). 
     In addition, while  FIG.  7    illustrates the UL-PRS resources  730  following the DL-PRS resources  720 , because they are not necessarily related to each other, they can occur in any order, and can even be interspersed with each other. Further, although  FIG.  7    illustrates three DL-PRS resources  720  and three UL-PRS resources  730 , as will be appreciated, there may be more or fewer than three each, and there may be different numbers of DL-PRS resources  720  and UL-PRS resources  730 . 
     The length/duration and periodicity of the measurement/transmission window  710  may not be explicitly signaled to the UE. Rather, it is implicit based on the configuration of the DL-PRS resources  720  and UL-PRS resources  730 . More specifically, the location server (e.g., location server  230 , LMF  270 , SLP  272 ) may configure DL-PRS resources  720  for the UE within the measurement/transmission window  710 , and configure the UE with UL-PRS resources  730  within the same measurement/transmission window  710 . The length/duration of the measurement/transmission window  710  is therefore from the first DL-PRS resource  720  or UL-PRS resource  730  of a PRS instance (here, DL-PRS resource  720 , labeled “DL-PRS  1 ”) to the last DL-PRS resource  720  or UL-PRS resource  730  of the PRS instance (here, UL-PRS resource  730 , labeled “UL-PRS  3 ”). As described above, the first downlink or uplink PRS resource of a PRS instance starts at the slot offset (as specified in either the DL-PRS resource set slot offset of the UL-PRS slot offset parameter). The last downlink or uplink PRS resource of the PRS instance occurs before the end of the PRS periodicity, at which point, a new PRS instance and measurement/transmission window  710  begins, and may correspond to the maximum resource offset value. Thus, the measurement/transmission window  710  may be roughly commensurate with a downlink or uplink PRS instance, except that it includes both downlink and uplink PRS resources during the same time period, meaning that both the downlink and uplink PRS instances have the same periodicity. That is, all DL-PRS resources across all TRPs and all UL-PRS resources are scheduled within the same window every DL-PRS periodicity, which is equal with the UL-PRS periodicity. 
     In an aspect, the duration of the measurement/transmission window  710  may always be a fraction of the periodicity (i.e., Tp PRS ). For example, the duration may correspond to the range [“DL-PRS-ResourceSetSlotOffset,” “DL-PRS-ResourceSetSlotOffset”+T PRS /10], or the range [“DL-PRS-ResourceSetSlotOffset”-T PRS /10, “DL-PRS-ResourceSetSlotOffset”+T PRS /10]. The selected/calculated duration may be rounded up to the next slot/subframe boundary. For example, if Tp PRS =5 ms, then T PRS /10=0.5 ms, so the duration can be rounded up to the range [“DL-PRS-ResourceSetSlotOffset”−1, “DL-PRS-ResourceSetSlotOffset”+1] ms. 
     In an aspect, for small periodicities (i.e., less than a threshold), the duration of the measurement/transmission window  710  may be equal to the periodicity, but for larger periodicities (i.e., greater than the threshold), the duration of the measurement/transmission window  710  may be smaller than the periodicity. For example, the threshold may be a periodicity of 32 slots or 32 ms. 
     In an aspect, the measurement/transmission window  710  may correspond to a DL-PRS measurement window, the parameters for which were described above. In that case, the location server may simply schedule all UL-PRS resources for the UE to be within the DL-PRS measurement window. 
     In an aspect, although the length of the measurement/transmission window  710  may not be signaled to the UE, the UE may signal (to the location server via LPP) the length of the measurement/transmission window  710  as a UE capability, the same as it may signal the length of the DL-PRS measurement window. The location server can then schedule the DL-PRS resources  720  and UL-PRS resources  730  within the signaled measurement/transmission window  710 . 
     As described above, all UL-PRS (or SRS-for-positioning) resources for positioning may be transmitted within a common measurement/transmission window, which may correspond to a DL-PRS measurement window as currently defined. However, there may be multiple DL-PRS measurement windows defined, and the UL-PRS would need to be transmitted within those measurement windows. For example, instead of one DL-PRS measurement window in which all DL-PRS resource sets are expected to be received, there may be one DL-PRS measurement window per DL-PRS resource set. In that case, UL-PRS resources could be scheduled within those DL-PRS measurement windows, making them measurement/transmission windows as well. 
       FIG.  8    is a diagram  800  of multiple measurement/transmission windows  810  during which both DL-PRS resources  820  and UL-PRS resources  830  are scheduled for a given UE, according to aspects of the disclosure. In the example of  FIG.  8   , the first measurement/transmission window  810   a  includes a single DL-PRS resource  820  (meaning there is only one DL-PRS resource  820  in that DL-PRS resource set) and no UL-PRS resources  830 . The second measurement/transmission window  810   b  also includes a single DL-PRS resource  820 , but also includes an UL-PRS resource  830 . As will be appreciated, this is merely an example, and there may be more or fewer DL and UL-PRS resources in the measurement/transmission windows  810 . 
     There are various benefits of transmitting downlink and uplink PRS in the same measurement/transmission window. For example, a UE may experience some amount of clock drift, and as such, if the downlink and uplink PRS transmission(s) for a given positioning session are too far apart in time (e.g., outside the measurement/transmission windows), the clock may have drifted enough to affect measurement accuracy. As another example, if the UE is in motion, the change in location of the UE between the downlink and uplink PRS transmission(s) for a given positioning session may affect accuracy if the downlink and uplink PRS transmission(s) are outside of the same measurement/transmission window. 
       FIG.  9    illustrates an exemplary method  900  of wireless communication, according to aspects of the disclosure. The method  900  may be performed by a UE (e.g., any of the UEs described herein) engaged in a positioning session with a plurality of TRPs. 
     At  910 , the UE receives a DL-PRS configuration specifying one or more DL-PRS resource sets of a DL-PRS instance, wherein each DL-PRS resource set is associated with a TRP of the plurality of TRPs, is configured with a transmission periodicity, comprises one or more DL-PRS resources that are transmitted according to the configured transmission periodicity of the DL-PRS resource set, wherein each DL-PRS resource is scheduled to be repeated over one or more consecutive slots, wherein one transmission instance of a repetition of the one or more DL-PRS resources of the one or more DL-PRS resource sets corresponds to a DL-PRS instance, wherein all DL-PRS resources of the one or more DL-PRS resource sets of the DL-PRS instance are scheduled within a time window, and wherein a duration of the time window is less than a duration defined by a configured transmission periodicity of one of the one or more DL-PRS resource sets. In an aspect, operation  910  may be performed by WWAN transceiver  310 , processing system  332 , memory component  340 , and/or positioning component  342 , any or all of which may be considered means for performing this operation. 
     At  920 , the UE receives an UL-PRS configuration specifying one or more UL-PRS resource sets, wherein each UL-PRS resource set comprises one or more UL-PRS resources, and wherein the one or more UL-PRS are scheduled within the time window. In an aspect, operation  920  may be performed by WWAN transceiver  310 , processing system  332 , memory component  340 , and/or positioning component  342 , any or all of which may be considered means for performing this operation. 
     At  930 , the UE optionally performs, during the time window, measurements of DL-PRS transmissions on one or more DL-PRS resources of the one or more DL-PRS resource sets, and reports, to a location server, the measurements of the DL-PRS transmissions. In an aspect, operation  930  may be performed by WWAN transceiver  310 , processing system  332 , memory component  340 , and/or positioning component  342 , any or all of which may be considered means for performing this operation. 
     At  940 , the UE optionally transmits, during the time window, at least one UL-PRS on the one or more UL-PRS resources. In an aspect, operation  940  may be performed by WWAN transceiver  310 , processing system  332 , memory component  340 , and/or positioning component  342 , any or all of which may be considered means for performing this operation. 
       FIG.  10    illustrates an exemplary method  1000  of wireless communication, according to aspects of the disclosure. The method  1000  may be performed by a positioning entity, such as location server  230 , LMF  270 , or SLP  272 . 
     At  1010 , the positioning entity transmits, to a UE (e.g., any of the UEs described herein) engaged in a positioning session with a plurality of TRPs, a DL-PRS configuration specifying one or more DL-PRS resource sets of a DL-PRS instance, wherein each DL-PRS resource set is associated with a TRP of the plurality of TRPs, is configured with a transmission periodicity, comprises one or more DL-PRS resources that are transmitted according to the configured transmission periodicity of the DL-PRS resource set, wherein each DL-PRS resource is scheduled to be repeated over one or more consecutive slots, wherein one transmission instance of a repetition of the one or more DL-PRS resources of the one or more DL-PRS resource sets corresponds to a DL-PRS instance, wherein all DL-PRS resources of the one or more DL-PRS resource sets of the DL-PRS instance are scheduled within a time window, and wherein a duration of the time window is less than a duration defined by a configured transmission periodicity of one of the one or more DL-PRS resource sets. In an aspect, operation  1010  may be performed by network interface(s)  390 , processing system  394 , memory component  396 , and/or positioning module  398 , any or all of which may be considered means for performing this operation. 
     At  1020 , the positioning entity transmits, to the UE, an UL-PRS configuration specifying one or more UL-PRS resource sets, wherein each UL-PRS resource set comprises one or more UL-PRS resources, and wherein the one or more UL-PRS are scheduled within the time window. In an aspect, operation  1020  may be performed by network interface(s)  390 , processing system  394 , memory component  396 , and/or positioning module  398 , any or all of which may be considered means for performing this operation. 
     Those of skill in the art will appreciate that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof. 
     Further, those of skill in the art will appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the aspects disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure. 
     The various illustrative logical blocks, modules, and circuits described in connection with the aspects disclosed herein may be implemented or performed with a general purpose processor, a DSP, an ASIC, an FPGA, or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. 
     The methods, sequences and/or algorithms described in connection with the aspects disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in random access memory (RAM), flash memory, read-only memory (ROM), erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal (e.g., UE). In the alternative, the processor and the storage medium may reside as discrete components in a user terminal. 
     In one or more exemplary aspects, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk and disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media. 
     While the foregoing disclosure shows illustrative aspects of the disclosure, it should be noted that various changes and modifications could be made herein without departing from the scope of the disclosure as defined by the appended claims. The functions, steps and/or actions of the method claims in accordance with the aspects of the disclosure described herein need not be performed in any particular order. Furthermore, although elements of the disclosure may be described or claimed in the singular, the plural is contemplated unless limitation to the singular is explicitly stated.