Wideband Positioning Reference Signal Processing via Sub-Nyquist Sampling

Abstract

Technologies for wireless communications are disclosed. In one aspect, a bandpass filter of a radio frequency front end (RFFE) of a user equipment (UE) receives an analog radio frequency (RF) signal having a first bandwidth associated with a first sampling rate, the analog RF signal including a positioning reference signal (PRS). An analog-to-digital converter (ADC) of the UE samples the analog RF signal at a second sampling rate to generate a digital RF signal representing the analog RF signal, wherein the ADC operates at a second bandwidth lower than the first bandwidth, and wherein the second sampling rate is the inverse of the first sampling rate multiplied by a folding factor of the first bandwidth. The digital RF signal is then output to a baseband processor of the UE.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims the benefit of U.S. Provisional Application No. 63 / 041,017, filed on June 18, 2020, entitled “WIDEBAND POSITIONING REFERENCE SIGNAL PROCESSING VIA SUB-NYQUIST SAMPLING,” and U.S. Non-Provisional Application No. 17 / 349,220, filed on June 16, 2021, entitled “WIDEBAND POSITIONING REFERENCE SIGNAL PROCESSING VIA SUB-NYQUIST SAMPLING,” both of which are assigned to the assignee of this application and are expressly incorporated herein by reference in their entirety.

[0003] Public background

[0004] 1. Public Domain

[0005] Aspects of the present disclosure generally relate to wireless communications.

[0006] 2. Description of Related Technologies

[0007] Wireless communication systems have evolved over several generations, including first-generation analog wireless telephone service (1G), second-generation (2G) digital wireless telephone service (including transitional 2.5G and 2.75G networks), third-generation (3G) high-speed data wireless service with Internet capabilities, and fourth-generation (4G) services (e.g., Long Term Evolution (LTE) or WiMax). Currently, there are 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), Global System for Mobile Communications (GSM), and the like.

[0008] The fifth generation (5G) wireless standard, known as New Radio (NR), calls for higher data transmission speeds, a greater number of connections, and better coverage, among other improvements. According to the Next Generation Mobile Networks Alliance, the 5G standard is designed to provide data rates of tens of megabits per second to each of tens of thousands of users, and 1 gigabit per second to dozens of employees on an office floor. Hundreds of thousands of simultaneous connections should be supported to support large sensor deployments. Therefore, the spectral efficiency of 5G mobile communications should be significantly improved compared to the current 4G standard. In addition, signaling efficiency should be improved and latency should be significantly reduced compared to current standards.

[0009] Overview

[0010] The following is a simplified summary of one or more aspects disclosed herein. Thus, the following summary should not be considered an exhaustive overview of all contemplated aspects, nor should it be considered to identify key or critical elements related to all contemplated aspects or to delineate the scope associated with any particular aspect. Accordingly, the sole purpose of the following summary is to present certain concepts related to one or more aspects of the mechanisms disclosed herein in a simplified form prior to the detailed description given below.

[0011] In one aspect, a wireless communication method performed by a user equipment (UE) includes: receiving an analog radio frequency (RF) signal having a first bandwidth associated with a first sampling rate at a bandpass filter of a radio frequency front end (RFFE) of the UE, the analog RF signal including a positioning reference signal (PRS); sampling the analog RF signal at a second sampling rate by an analog-to-digital converter (ADC) of the UE to generate a digital RF signal representing the analog RF signal, wherein the ADC operates at a second bandwidth lower than the first bandwidth, and wherein the second sampling rate is the first sampling rate multiplied by a reciprocal of a folding factor of the first bandwidth; and outputting the digital RF signal to a baseband processor of the UE.

[0012] In one aspect, a user equipment (UE) includes: a memory; a bandpass filter of a radio frequency front end (RFFE) configured to receive an analog radio frequency (RF) signal having a first bandwidth associated with a first sampling rate, the analog RF signal including a positioning reference signal (PRS); an analog-to-digital converter (ADC); and a baseband processor communicatively coupled to the ADC, wherein the ADC is configured to: sample the analog RF signal at a second sampling rate to generate a digital RF signal representing the analog RF signal, wherein the ADC operates at a second bandwidth lower than the first bandwidth, and wherein the second sampling rate is a reciprocal of a folding factor of the first bandwidth multiplied by the first sampling rate; and output the digital RF signal to the baseband processor.

[0013] In one aspect, a user equipment (UE) includes: a device for receiving an analog radio frequency (RF) signal having a first bandwidth associated with a first sampling rate at a bandpass filter of a radio frequency front end (RFFE) of the UE, the analog RF signal including a positioning reference signal (PRS); a device for sampling the analog RF signal at a second sampling rate to generate a digital RF signal representing the analog RF signal, wherein the device for sampling operates at a second bandwidth lower than the first bandwidth, and wherein the second sampling rate is the first sampling rate multiplied by a reciprocal of a folding factor of the first bandwidth; and a device for outputting the digital RF signal to a baseband processor of the UE.

[0014] In one aspect, a non-transitory computer-readable medium stores computer-executable instructions that, when executed by a user equipment (UE), cause the UE to: receive an analog radio frequency (RF) signal having a first bandwidth associated with a first sampling rate at a bandpass filter of a radio frequency front end (RFFE) of the UE, the analog RF signal including a positioning reference signal (PRS); sample the analog RF signal at a second sampling rate by an analog-to-digital converter (ADC) to generate a digital RF signal representing the analog RF signal, wherein the ADC operates at a second bandwidth lower than the first bandwidth, and wherein the second sampling rate is a reciprocal of a folding factor of the first bandwidth multiplied by the first sampling rate; and output the digital RF signal to a baseband processor of the UE.

[0015] Other objects and advantages associated with the aspects disclosed herein will be apparent to those skilled in the art based on the drawings and detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings are presented to aid in describing the aspects of the disclosure and are provided solely for illustration of the aspects and not limitation thereof.

[0018] Figure 1 An example wireless communication system is illustrated in accordance with aspects of the present disclosure.

[0019] Figure 2A and 2B Example wireless network structures according to aspects of the present disclosure are illustrated.

[0020] Figure 3A 、 3B 3C 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, and configured to support communications as taught herein.

[0021] Figure 4 is a block diagram of an example RF front-end receiver architecture according to aspects of the present disclosure.

[0022] Figure 5 is a diagram illustrating an example frame structure according to aspects of the present disclosure.

[0023] Figure 6 is a diagram of an example radio frequency (RF) signal processing procedure in accordance with aspects of the present disclosure.

[0024] Figure 7 is a graph illustrating the relationship between transmission bandwidth and measurement accuracy according to aspects of the present disclosure.

[0025] Figure 8 A comparison between sampling a wireless signal at its Nyquist rate and at its sub-Nyquist rate is illustrated in accordance with aspects of the present disclosure.

[0026] Figure 9 Examples of folded interleaved subcarrier sets in accordance with aspects of the present disclosure are illustrated.

[0027] Figure 10

[0014] Example wireless communication methods in accordance with aspects of the present disclosure are illustrated.

[0028] Detailed description

[0029] Aspects of the present disclosure are provided below in the description and related drawings of various examples provided for illustrative purposes. Alternative aspects can be designed without departing from the scope of the present disclosure. In addition, well-known elements in the present disclosure will not be described in detail or will be omitted to avoid obscuring the relevant details of the present disclosure.

[0030] 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.

[0031] Those skilled 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 referred to throughout the following description 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 specific application, in part on the desired design, in part on the corresponding technology, etc.

[0032] In addition, many aspects are described in terms of sequences of actions performed by, for example, elements of a computing device. It will be appreciated that the various actions described herein can be performed by dedicated circuits (e.g., application specific integrated circuits (ASICs)), by program instructions being executed by one or more processors, or by a combination of the two. In addition, the sequences of actions described herein may be considered to be fully embodied within any form of non-transient computer-readable storage medium having stored therein a corresponding set of computer instructions that, upon execution, will cause or instruct an associated processor of a device to perform the functionality described herein. Thus, various aspects of the present disclosure may be embodied in several different forms, all of which have been contemplated as falling within the scope of the claimed subject matter. In addition, for each aspect described herein, the corresponding form of any such aspect may be described herein as, for example, "logic configured to perform the described actions."

[0033] As used herein, the terms "user equipment" (UE) and "base station" are not intended to be specific to or otherwise limited to any particular radio access technology (RAT), unless otherwise specified. In general, a UE can be any wireless communication device used by a user to communicate on a wireless communication network (e.g., a mobile phone, a router, a tablet computer, a laptop computer, a consumer asset location device, a wearable device (e.g., a smart watch, glasses, augmented reality (AR) / virtual reality (VR) headset, etc.), a vehicle (e.g., a car, a motorcycle, a bicycle, etc.), an Internet of Things (IoT) device, etc.). A UE can be mobile or can be stationary (e.g., at certain times) and can communicate with a radio access network (RAN). As used herein, the term "UE" can be interchangeably referred to as an "access terminal" or "AT," "client device," "wireless device," "subscriber device," "subscriber terminal," "subscriber station," "user terminal" or "UT," "mobile device," "mobile terminal," "mobile station," or variations thereof. In general, a UE can communicate with a core network via the RAN, and through the core network, the UE can connect to external networks (such as the Internet) and other UEs. Of course, other mechanisms for connecting to the core network and / or the Internet are also possible for the UE, such as through a wired access network, a wireless local area network (WLAN) network (e.g., based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 specification, etc.), etc.

[0034] A base station may operate according to one of several RATs to communicate with UEs, depending on the network in which it is deployed, and may be referred to interchangeably as an access point (AP), network node, Node B, evolved Node B (eNB), next-generation eNB (ng-eNB), new radio (NR) Node B (also referred to as gNB or gNodeB), etc. A base station may primarily be used 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 pure edge node signaling functionality, while in other systems, a base station may provide additional control and / or network management functionality. The communication link by which a UE may send signals to a base station is referred to as an uplink (UL) channel (e.g., a reverse traffic channel, a reverse control channel, an access channel, etc.). The communication link by which a base station may send signals to a UE is referred to as 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) may refer to either an uplink / reverse traffic channel or a downlink / forward traffic channel.

[0035] The term "base station" may refer to a single physical transmit receive point (TRP) or may refer 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 the base station antenna corresponding to the cell (or several cell sectors) of the base station. Where the term "base station" refers to multiple co-located physical TRPs, the physical TRP may be the antenna array of the base station (e.g., as in a multiple-input multiple-output (MIMO) system or where the base station employs beamforming). Where the term "base station" refers to multiple non-co-located physical TRPs, the physical TRP may be a distributed antenna system (DAS) (a network of spatially separated antennas connected to a common source via a transmission 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 a serving base station that receives measurement reports from a UE and a neighbor base station whose reference radio frequency (RF) signal the UE is measuring. Since a TRP is the point from which a base station transmits and receives wireless signals, as used herein, references to transmissions from or receptions at a base station should be understood as references to the specific TRP of that base station.

[0036] In some implementations that support UE positioning, a base station may not support wireless access for the UE (e.g., may not support data, voice, and / or signaling connections for the UE), but may instead transmit a reference signal to the UE to be measured by the UE and / or may receive and measure signals transmitted by the UE. Such a base station may be referred to as a positioning tower (e.g., when transmitting signals to the UE) and / or as a position measurement unit (e.g., when receiving and measuring signals from the UE).

[0037] An "RF signal" comprises an electromagnetic wave of a given frequency that transmits 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, due to the propagation characteristics of each RF signal through a multipath channel, the receiver may receive multiple "RF signals" corresponding to each transmitted RF signal. The same RF signal transmitted over different paths between a transmitter and a 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 the context clearly indicates whether the term "signal" refers to a wireless signal or an RF signal.

[0038] Figure 1 An example wireless communication system 100 is illustrated in accordance with various aspects of the present disclosure. The wireless communication system 100, which may also be referred to as a wireless wide area network (WWAN), may include various base stations 102 (labeled "BS") and various UEs 104. The base stations 102 may include macrocell base stations (high-power cellular base stations) and / or small cell base stations (low-power cellular base stations). In one aspect, the macrocell base stations may include eNBs and / or ng-eNBs (where the wireless communication system 100 corresponds to an LTE network), or gNBs (where the wireless communication system 100 corresponds to an NR network), or a combination of both, and the small cell base stations may include femtocells, picocells, microcells, and the like.

[0039] Each base station 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)) via backhaul links 122, and through the core network 170 to one or more location servers 172 (e.g., a location management function (LMF) or a secure user plane location (SUPL) location platform (SLP)). The location server 172 may be part of the core network 170 or may be external to the core network 170. Among other functions, the base stations 102 may also perform functions related to one or more of communicating user data, radio channel encryption and decryption, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection setup and release, load balancing, distribution of non-access stratum (NAS) messages, NAS node selection, synchronization, RAN sharing, multimedia broadcast multicast service (MBMS), subscriber and equipment tracking, RAN information management (RIM), paging, positioning, and delivery of alert messages. Base stations 102 may communicate with each other via backhaul links 134 (which may be wired or wireless) directly or indirectly (e.g., via EPC / 5GC).

[0040] Base stations 102 may communicate wirelessly with UEs 104. Each base station 102 may provide communication coverage for a respective geographic coverage area 110. In one aspect, one or more cells may be supported by base station 102 in each geographic coverage area 110. A "cell" is a logical communication entity used to communicate with a base station (e.g., on a certain frequency resource, which may be referred to as a carrier frequency, component carrier, carrier, frequency band, etc.) and may be associated with an identifier (e.g., a physical cell identifier (PCI), an enhanced cell identifier (ECI), a virtual cell identifier (VCI), a cell global identifier (CGI), etc.) to distinguish between cells operating on the same or different carrier frequencies. 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 other) that may provide access to different types of UEs. Because a cell is supported by a specific base station, the term "cell" may refer to either or both the logical communication entity and the base station supporting the logical communication entity, depending on the context. Additionally, 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 (e.g., a sector) of a base station, in the sense that a carrier frequency may be detected and used for communications within a portion of geographic coverage area 110.

[0041] Although the geographic coverage areas 110 of adjacent macrocell base stations 102 may partially overlap (e.g., in a handover region), some geographic coverage areas 110 may be substantially overlapped by a larger geographic coverage area 110. For example, a small cell base station 102' (labeled "SC" for "small cell") may have a geographic coverage area 110' that substantially overlaps with the geographic coverage areas 110 of one or more macrocell base stations 102. A network that includes both small cell and macrocell base stations may be referred to as a heterogeneous network. A heterogeneous network may also include a home eNB (HeNB), which may provide service to a restricted group known as a closed subscriber group (CSG).

[0042] The communication link 120 between the base station 102 and the UE 104 may include uplink (also known as reverse link) transmissions from the UE 104 to the base station 102 and / or downlink (DL) (also known as forward link) transmissions from the base station 102 to the UE 104. The communication link 120 may utilize MIMO antenna technology, including spatial multiplexing, beamforming, and / or transmit diversity. The communication link 120 may utilize one or more carrier frequencies. The allocation of carriers may be asymmetric with respect to the downlink and uplink (e.g., more or fewer carriers may be allocated to the downlink than to the uplink).

[0043] The wireless communication system 100 may further include a wireless local area network (WLAN) access point (AP) 150 in communication with a WLAN station (STA) 152 in an unlicensed spectrum (e.g., 5 GHz) via a communication link 154. When communicating in the unlicensed spectrum, the WLAN STA 152 and / or the WLAN AP 150 may perform a clear channel assessment (CCA) or listen-before-talk (LBT) procedure to determine whether a channel is available before communicating.

[0044] Small cell base station 102' can operate in licensed and / or unlicensed spectrum. When operating in unlicensed spectrum, small cell base station 102' can employ LTE or NR technology and use the same 5 GHz unlicensed spectrum used by WLAN AP 150. Small cell base station 102' employing LTE / 5G in unlicensed spectrum can boost coverage and / or increase capacity of the access network. NR in unlicensed spectrum can be referred to as NR-U. LTE in unlicensed spectrum can be referred to as LTE-U, Licensed Assisted Access (LAA), or MulteFire.

[0045] The wireless communication system 100 may further include a millimeter wave (mmW) base station 180 that can operate in mmW and / or near-mmW frequencies to communicate with a UE 182. Extremely high frequencies (EHF) are part of the RF spectrum within the electromagnetic spectrum. EHF has a range of 30 GHz to 300 GHz and a wavelength between 1 mm and 10 mm. Radio waves in this frequency band may be referred to as millimeter waves. Near-mmW frequencies extend down to 3 GHz with a wavelength of 100 mm. Super high frequency (SHF) frequency bands extend between 3 GHz and 30 GHz and are also referred to as centimeter waves. Communications using mmW / near-mmW radio frequency bands 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) on the mmW communication link 184 to compensate for the extremely high path loss and short range. Furthermore, it will be appreciated that, in alternative configurations, one or more base stations 102 may also transmit using mmW or near-mmW frequencies and beamforming. Accordingly, it will be appreciated that the foregoing explanation is merely an example, and should not be construed as limiting the various aspects disclosed herein.

[0046] Transmit beamforming is a technique for focusing an RF signal in a specific direction. Conventionally, when a network node (e.g., a base station) broadcasts an RF signal, it broadcasts the signal in all directions (omnidirectionally). Using 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 the receiving device with a faster (in terms of data rate) and stronger RF signal. In order to change the directionality of the RF signal during transmission, the network node can control the phase and relative amplitude of the RF signal at each of the one or more transmitters broadcasting the RF signal. For example, the network node can use an antenna array (referred to as a "phased array" or "antenna array") that generates a beam of RF waves that can be "steered" in different directions without actually moving the antennas. Specifically, the RF currents from the transmitters are fed to the individual antennas in the correct phase relationship so that the radio waves from the separate antennas add together in the desired direction to increase radiation, while canceling out in undesired directions to suppress radiation.

[0047] The transmit beams can be quasi-colocated, which means that they appear to the receiver (e.g., UE) to have the same parameters, regardless of whether the transmit antennas of the network node themselves are physically colocated. In NR, there are four types of quasi-colocation (QCL) relationships. Specifically, a given type of QCL relationship means that certain parameters about the second reference RF signal on the second beam can be derived from information about the source reference RF signal on the source beam. Therefore, 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 the 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 the 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 the second reference RF signal transmitted on the same channel. If the source reference RF signal is QCL type D, the receiver may use the source reference RF signal to estimate spatial reception parameters of a second reference RF signal transmitted on the same channel.

[0048] In receive beamforming, a receiver uses a receive beam to amplify the RF signal detected on a given channel. For example, the receiver may increase the gain setting of the antenna array and / or adjust the phase setting of the antenna array in a particular direction to amplify (e.g., increase the gain level of) the RF signal received from that direction. Thus, when a receiver is said to be beamforming in a certain direction, it means that 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 for 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 and noise ratio (SINR), etc.) for the RF signal received from that direction.

[0049] The transmit beam and receive beam can be spatially correlated. The spatial relationship means that the parameters of the second beam (e.g., transmit or receive beam) used for the second reference signal can be derived from information about the first beam (e.g., receive beam or transmit beam) of the first reference signal. For example, the UE can use a specific receive beam to receive a reference downlink reference signal (e.g., a synchronization signal block (SSB)) from the base station. The UE can then form a transmit beam based on the parameters of the receive beam for sending an uplink reference signal (e.g., a sounding reference signal (SRS)) to the base station.

[0050] Note that depending on the entity forming the "downlink" beam, the beam can be a transmit beam or a receive beam. For example, if the base station is forming a downlink beam to transmit a reference signal to the UE, the downlink beam is a transmit beam. However, if the UE is forming a downlink beam, the downlink beam is a receive beam for receiving downlink reference signals. Similarly, depending on the entity forming the "uplink" beam, the beam can be a transmit beam or a receive beam. For example, if the base station is forming an uplink beam, the uplink beam is an uplink receive beam, while if the UE is forming an uplink beam, the uplink beam is an uplink transmit beam.

[0051] In 5G, the 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). The mmW band generally includes the FR2, FR3, and FR4 frequency ranges. As such, the terms "mmW" and "FR2" or "FR3" or "FR4" can generally be used interchangeably.

[0052] 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 the UE 104 / 182 and on the cell in which the UE 104 / 182 performs an initial radio resource control (RRC) connection establishment procedure or initiates an RRC connection re-establishment procedure. The primary carrier carries all common control channels as well as UE-specific control channels and can be a carrier in a licensed frequency (however, this is not always the case). The secondary carrier is a carrier operating on a second frequency (e.g., FR2) that can be configured once an RRC connection is established between the UE 104 and the anchor carrier and can be used to provide additional radio resources. In some cases, the secondary carrier can be a carrier in an unlicensed frequency. The secondary carrier may contain only necessary signaling information and signals, for example, UE-specific signaling information and signals may not be present in the secondary carrier, since both the 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 carrier. The network can change the primary carrier for any UE 104 / 182 at any time. For example, this is done to balance the load on different carriers. Since a "serving cell" (whether PCell or SCell) corresponds to the carrier frequency / component carrier that a base station is using to communicate, the terms "cell", "serving cell", "component carrier", "carrier frequency", etc. may be used interchangeably.

[0053] For example, still referring to Figure 1 In one embodiment, one of the frequencies utilized by the macrocell base station 102 may be an anchor carrier (or "PCell"), and the other frequencies utilized by the macrocell base station 102 and / or the mmW base station 180 may be secondary carriers ("SCells"). Simultaneous transmission and / or reception of multiple carriers enables the UE 104 / 182 to significantly increase its data transmission and / or reception rate. For example, two 20 MHz aggregated carriers in a multi-carrier system would theoretically result in a two-fold increase in data rate (i.e., 40 MHz) compared to the data rate achieved by a single 20 MHz carrier.

[0054] The wireless communication system 100 may further include a UE 164 that may communicate with the macrocell base station 102 over a communication link 120 and / or with the mmW base station 180 over a mmW communication link 184. For example, the macrocell 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.

[0055] exist Figure 1 In the example of FIG, any one of the UEs (for simplicity in FIG Figure 1 104) can receive signals 124 from one or more Earth-orbiting spacecraft (SVs) 112 (e.g., satellites). In one aspect, SVs 112 can be part of a satellite positioning system that UEs 104 can use as an independent source of location information. Satellite positioning systems typically include a system of transmitters (e.g., SVs 112) positioned to enable a receiver (e.g., UE 104) to determine the receiver's location on or above the Earth based, at least in part, on positioning signals (e.g., signals 124) received from these transmitters. Such transmitters typically transmit signals marked with a repeating pseudorandom noise (PN) code of a set number of chips. While typically located in SVs 112, transmitters can also sometimes be located in ground-based control stations, base stations 102, and / or other UEs 104. UEs 104 can include one or more dedicated receivers specifically designed to receive signals 124 from SVs 112 to derive geographic location information.

[0056] In a satellite positioning system, the use of signal 124 can be augmented by various satellite-based augmentation systems (SBAS), which may be associated with or otherwise enabled for use with one or more global and / or regional navigation satellite systems. For example, SBAS may include augmentation systems that provide integrity information, differential corrections, etc., such as the Wide Area Augmentation System (WAAS), the European Geostationary Navigation Overlay Service (EGNOS), the Multifunctional Satellite Augmentation System (MSAS), the Global Positioning System (GPS) Assisted Geo-Augmented Navigation, or the GPS and Geo-Augmented Navigation System (GAGAN), etc. Thus, as used herein, a satellite positioning system may include any combination of one or more global and / or regional navigation satellites associated with such one or more satellite positioning systems.

[0057] In one aspect, SV 112 may additionally or alternatively be part of one or more non-terrestrial networks (NTNs). In an NTN, SV 112 is connected to an earth station (also referred to as a ground station, NTN gateway, or gateway), which in turn is connected to elements in the 5G network, such as a modified base station 102 (without a ground antenna) or a network node in a 5GC. This element, in turn, provides access to other elements in the 5G network and ultimately provides access to entities external to the 5G network, such as Internet web servers and other user devices. In this way, UE 104 can receive communication signals (e.g., signal 124) from SV 112, instead of or in addition to receiving communication signals from terrestrial base station 102.

[0058] The wireless communication system 100 may further include one or more UEs (such as UE 190) that are indirectly connected to one or more communication networks via one or more device-to-device (D2D) or peer-to-peer (P2P) links (referred to as “side links”). Figure 1 In the example shown in FIG1 , UE 190 has a D2D P2P link 192 with a UE 104 connected to a base station 102 (e.g., UE 190 can indirectly obtain cellular connectivity therefrom), and a D2D P2P link 194 with a WLAN STA 152 connected to a WLAN AP 150 (e.g., UE 190 can indirectly obtain WLAN-based Internet connectivity therefrom). In one example, the D2D P2P links 192 and 194 can use any well-known D2D RAT (such as LTE Direct (LTE-D), WiFi Direct (WiFi-D), etc.) to support.

[0059] Figure 2AAn example wireless network architecture 200 is illustrated. For example, 5GC 210 (also known as Next Generation Core (NGC)) can be functionally considered to include control plane (C-plane) functions 214 (e.g., UE registration, authentication, network access, gateway selection, etc.) and user plane (U-plane) functions 212 (e.g., UE gateway functions, access to data networks, IP routing, etc.), which operate in conjunction to form the core network. A user plane interface (NG-U) 213 and a control plane interface (NG-C) 215 connect gNBs 222 to 5GC 210, specifically to user plane functions 212 and control plane functions 214, respectively. In additional configurations, ng-eNBs 224 can also connect to 5GC 210 via NG-C 215 to control plane functions 214 and NG-U 213 to user plane functions 212. Furthermore, ng-eNBs 224 can communicate directly with gNBs 222 via backhaul connections 223. In some configurations, the next generation RAN (NG-RAN) 220 may have one or more gNBs 222, while other configurations include one or more ng-eNBs 224 and one or more gNBs 222. The gNB 222 or the ng-eNB 224 (or both) may communicate with one or more UEs 204 (e.g., any of the UEs described herein).

[0060] Another optional aspect may include a location server 230 that can be in communication with the 5GC 210 to provide location assistance for the UE 204. The location server 230 can be implemented as multiple separate servers (e.g., physically separate servers, different software modules on a single server, different software modules spread across multiple physical servers, etc.), or alternatively, each can correspond to a single server. The location server 230 can be configured to support one or more location services for the UE 204, which can be connected to the location server 230 via the core network, the 5GC 210, and / or via the Internet (not illustrated). In addition, the location server 230 can be integrated into a component of the core network, or alternatively can be external to the core network (e.g., a third-party server, such as an original equipment manufacturer (OEM) server or a service server).

[0061] Figure 2B Another example wireless network structure 250 is illustrated. 5GC 260 (which may correspond to Figure 2AThe 5GC 210 in the 5GC 210 can be functionally considered as a control plane function (provided by the access and mobility management function (AMF) 264) and a user plane function (provided by the user plane function (UPF) 262), which operate in conjunction to form the core network (i.e., the 5GC 260). The functions of the AMF 264 include registration management, connection management, reachability management, mobility management, lawful interception, session management (SM) message transmission between one or more UEs 204 (e.g., any UE described herein) and a session management function (SMF) 266, a transparent proxy service for routing SM messages, access authentication and access authorization, short message service (SMS) message transmission between the UE 204 and a 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 intermediate keys established as a result of the UE 204 authentication process. In the case of authentication based on the UMTS (Universal Mobile Telecommunications System) Subscriber Identity Module (USIM), the AMF 264 retrieves security material from the AUSF. The functionality of the AMF 264 also includes Security Context Management (SCM). The SCM receives keys from the SEAF, which are used by the SCM to derive keys that are specific to the access network. The functionality of the AMF 264 also includes: location service management for regulatory services, location service message transmission between the UE 204 and the Location Management Function (LMF) 270 (which acts as the location server 230), location service message transmission between the NG-RAN 220 and the LMF 270, EPS bearer identifier allocation for interworking with the Evolved Packet System (EPS), and UE 204 mobility event notification. In addition, the AMF 264 also supports the functionality of non-3GPP (3rd Generation Partnership Project) access networks.

[0062] The functions of the UPF 262 include: serving as an anchor point for intra-RAT / inter-RAT mobility (when applicable), serving as an external protocol data unit (PDU) session point for interconnection 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 one or more "end markers" to the source RAN node. The UPF 262 may also support the transmission of location service messages between the UE 204 and a location server (such as the SLP 272) on the user plane.

[0063] The functions of the SMF 266 include session management, UE Internet Protocol (IP) address allocation and management, selection and control of user plane functions, traffic steering configuration for routing traffic to the correct destination at the UPF 262, partial control of policy enforcement and QoS, and downlink data notification. The interface that the SMF 266 uses to communicate with the AMF 264 is called the N11 interface.

[0064] Another optional aspect may include an LMF 270 that can be in communication with the 5GC 260 to provide location assistance for the UE 204. The LMF 270 can be implemented as multiple separate servers (e.g., physically separate servers, different software modules on a single server, different software modules spread across multiple physical servers, etc.), or alternatively, each can correspond to a single server. The LMF 270 can be configured to support one or more location services for the UE 204, which can connect to the LMF 270 via the core network, the 5GC 260, and / or via the Internet (not illustrated). The SLP 272 may support similar functionality as the LMF 270, but while the LMF 270 may communicate with the AMF 264, the NG-RAN 220, and the UE 204 on the control plane (e.g., using interfaces and protocols intended to convey signaling messages but not voice or data), the SLP 272 may communicate with the UE 204 and external clients (e.g., using protocols intended to carry voice and / or data, such as Transmission Control Protocol (TCP) and / or IP) on the user plane. Figure 2B (not shown) communications.

[0065] The user plane interface 263 and the control plane interface 265 connect the 5GC 260 (and in particular, the UPF 262 and the AMF 264, respectively) to one or more gNBs 222 and / or ng-eNBs 224 in the NG-RAN 220. The interface between the gNB 222 and / or ng-eNB 224 and the AMF 264 is referred to as the "N2" interface, while the interface between the gNB 222 and / or ng-eNB 224 and the UPF 262 is referred to as the "N3" interface. The gNBs 222 and / or ng-eNBs 224 of the NG-RAN 220 can communicate directly with each other via the backhaul connection 223, which is referred to as the "Xn-C" interface. One or more of the gNBs 222 and / or ng-eNBs 224 can communicate with one or more UEs 204 over a radio interface, which is referred to as the "Uu" interface.

[0066] The functionality of the gNB 222 is divided between the gNB Central Unit (gNB-CU) 226 and one or more gNB Distributed Units (gNB-DUs) 228. The interface 232 between the gNB-CU 226 and one or more gNB-DUs 228 is referred to as the "F1" interface. The gNB-CU 226 is a logical node that includes base station functions such as user data delivery, mobility control, radio access network sharing, positioning, and session management, in addition to those functions specifically assigned to the gNB-DU 228. More specifically, the gNB-CU 226 hosts the Radio Resource Control (RRC), Service Data Adaptation Protocol (SDAP), and Packet Data Convergence Protocol (PDCP) protocols for the gNB 222. The gNB-DU 228 is a logical node that hosts the Radio Link Control (RLC), Medium Access Control (MAC), and Physical (PHY) layers of the gNB 222. Its operation is controlled by the gNB-CU 226. One gNB-DU 228 can support one or more cells, and one cell is supported by only one gNB-DU 228. Therefore, the UE 204 communicates with the gNB-CU 226 via the RRC, SDAP, and PDCP layers, and communicates with the gNB-DU 228 via the RLC, MAC, and PHY layers.

[0067] Figure 3A 、 3B and 3C illustrate that a UE 302 (which may correspond to any UE described herein), a base station 304 (which may correspond to any base station described herein), and a network entity 306 (which may correspond to or embody any network function described herein, including location server 230 and LMF 270, or alternatively may be independent thereof) may be included. Figure 2A and 2B 20 and / or 5GC 210 / 260 infrastructure, such as a dedicated network, to support file transfer operations as taught herein. It will be appreciated that these components may be implemented in different types of devices (e.g., in an ASIC, in a system-on-chip (SoC), etc.) in different implementations. The illustrated components may also be incorporated into other devices in a communication system. For example, other devices in the system may include components similar to those described to provide similar functionality. Furthermore, a given device may include one or more of these components. For example, a device may include multiple transceiver components that enable the device to operate on multiple carriers and / or communicate via different technologies.

[0068] UE 302 and base station 304 each include one or more wireless wide area network (WWAN) transceivers 310 and 350, respectively, providing means for communicating (e.g., means for transmitting, means for receiving, means for measuring, means for tuning, means for refraining from transmitting, etc.) via one or more wireless communication networks (not shown) (e.g., NR network, LTE network, GSM network, etc.). WWAN transceivers 310 and 350 can each be connected to one or more antennas 316 and 356, respectively, for communicating with other network nodes (e.g., other UEs, access points, base stations (e.g., eNB, gNB), etc.) over a wireless communication medium of interest (e.g., a set of time / frequency resources in a specific spectrum) via at least one designated RAT (e.g., NR, LTE, GSM, etc.). The WWAN transceivers 310 and 350 can be configured in various ways according to a designated RAT to transmit and encode signals 318 and 358 (e.g., messages, indications, information, etc.), and conversely, to receive and decode signals 318 and 358 (e.g., messages, indications, information, pilots, etc.). Specifically, the WWAN transceivers 310 and 350 include one or more transmitters 314 and 354, respectively, to transmit and encode signals 318 and 358, respectively, and one or more receivers 312 and 352, respectively, to receive and decode signals 318 and 358, respectively.

[0069] At least in some cases, the UE 302 and the base station 304 each further include one or more short-range wireless transceivers 320 and 360, respectively. The short-range wireless transceivers 320 and 360 can be connected to one or more antennas 326 and 366, respectively, and provide for communication via at least one designated RAT (e.g., WiFi, LTE-D, The short-range wireless transceivers 320 and 360 are devices (e.g., devices for transmitting, devices for receiving, devices for measuring, devices for tuning, devices for suppressing transmission, etc.) for communicating with other network nodes (such as other UEs, access points, base stations, etc.) over a wireless communication medium of interest (e.g., PC5, dedicated short-range communication (DSRC), wireless access in vehicular environments (WAVE), near field communication (NFC), etc.). The short-range wireless transceivers 320 and 360 can be configured in various ways according to the specified RAT to transmit and encode signals 328 and 368 (e.g., messages, indications, information, etc.), and conversely, to receive and decode signals 328 and 368 (e.g., messages, indications, information, pilots, etc.). Specifically, the short-range wireless transceivers 320 and 360 respectively include one or more transmitters 324 and 364 for transmitting and encoding signals 328 and 368, respectively, and one or more receivers 322 and 362 for receiving and decoding signals 328 and 368, respectively. As specific examples, the short-range wireless transceivers 320 and 360 may be WiFi transceivers, transceiver, and / or transceiver, NFC transceiver, or vehicle-to-vehicle (V2V) and / or vehicle-to-everything (V2X) transceiver.

[0070] In at least some cases, UE 302 and base station 304 also include satellite signal receivers 330 and 370. Satellite signal receivers 330 and 370 can be connected to one or more antennas 336 and 376, respectively, and can provide means for receiving and / or measuring satellite positioning / communication signals 338 and 378, respectively. If satellite signal receivers 330 and 370 are satellite positioning system receivers, satellite positioning / communication signals 338 and 378 can be 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. If satellite signal receivers 330 and 370 are non-terrestrial network (NTN) receivers, satellite positioning / communication signals 338 and 378 can be communication signals (e.g., carrying control and / or user data) originating from a 5G network. Satellite signal receivers 330 and 370 may include any suitable hardware and / or software for receiving and processing satellite positioning / communication signals 338 and 378, respectively. Satellite signal receivers 330 and 370 request information and operations from other systems as appropriate, and in at least some cases perform calculations to determine the respective positions of UE 302 and base station 304 using measurements obtained by any suitable satellite positioning system algorithm.

[0071] The base station 304 and the network entity 306 each include one or more network transceivers 380 and 390, respectively, to provide means (e.g., means for transmitting, means for receiving, etc.) for communicating with other network entities (e.g., other base stations 304, other network entities 306). For example, the base station 304 may employ one or more network transceivers 380 to communicate with other base stations 304 or network entities 306 over one or more wired or wireless backhaul links. As another example, the network entity 306 may employ one or more network transceivers 390 to communicate with one or more base stations 304 over one or more wired or wireless backhaul links, or with other network entities 306 over one or more wired or wireless core network interfaces.

[0072] A transceiver can be configured to communicate over a wired or wireless link. A transceiver (whether a wired transceiver or a wireless transceiver) includes transmitter circuitry (e.g., transmitters 314, 324, 354, 364) and receiver circuitry (e.g., receivers 312, 322, 352, 362). A transceiver can be an integrated device in some implementations (e.g., implementing the transmitter circuitry and receiver circuitry in a single device), can include separate transmitter circuitry and separate receiver circuitry in some implementations, or can be implemented in other ways in other implementations. The transmitter circuitry and receiver circuitry of a wired transceiver (e.g., network transceivers 380 and 390 in some implementations) can be coupled to one or more wired network interface ports. Wireless transmitter circuitry (e.g., transmitters 314, 324, 354, 364) may include or be coupled to multiple antennas (e.g., antennas 316, 326, 356, 366), such as antenna arrays, which permit the respective device (e.g., UE 302, base station 304) to perform transmit "beamforming," as described herein. Similarly, wireless receiver circuitry (e.g., receivers 312, 322, 352, 362) may include or be coupled to multiple antennas (e.g., antennas 316, 326, 356, 366), such as antenna arrays, which permit the respective device (e.g., UE 302, base station 304) to perform receive beamforming, as described herein. In one aspect, the transmitter circuitry and the receiver circuitry may share the same multiple antennas (e.g., antennas 316, 326, 356, 366) so that the respective device can only receive or transmit at a given time, but not both simultaneously. The wireless transceivers (eg, WWAN transceivers 310 and 350, short-range wireless transceivers 320 and 360) may also include a network listening module (NLM) or the like for performing various measurements.

[0073] As used herein, various wireless transceivers (e.g., transceivers 310, 320, 350, and 360, and in some implementations, network transceivers 380 and 390) and wired transceivers (e.g., network transceivers 380 and 390 in some implementations) may be generally characterized as a "transceiver," "at least one transceiver," or "one or more transceivers." Thus, whether a particular transceiver is a wired or wireless transceiver may be inferred from the type of communication being performed. For example, backhaul communications between network devices or servers generally involve signaling via a wired transceiver, while wireless communications between a UE (e.g., UE 302) and a base station (e.g., base station 304) generally involve signaling via a wireless transceiver.

[0074] UE 302, base station 304, and network entity 306 also include other components that can be used in conjunction with the operations disclosed herein. UE 302, base station 304, and network entity 306 each include one or more processors 332, 384, and 394 for providing functionality related to, for example, wireless communication and for providing other processing functionality. Processors 332, 384, and 394 can thus provide means for processing, such as means for determining, means for computing, means for receiving, means for transmitting, means for indicating, and the like. In one aspect, processors 332, 384, and 394 can include, for example, one or more general-purpose processors, multi-core processors, central processing units (CPUs), ASICs, digital signal processors (DSPs), field programmable gate arrays (FPGAs), other programmable logic devices or processing circuitry, or various combinations thereof.

[0075] UE 302, base station 304, and network entity 306 include memory circuitry that implements memory 340, 386, and 396, respectively (e.g., each including a memory device), for maintaining information (e.g., information indicating reserved resources, thresholds, parameters, etc.). Memories 340, 386, and 396 can thus provide means for storing, means for retrieving, means for maintaining, etc. In some cases, UE 302, base station 304, and network entity 306 can include positioning components 342, 388, and 398, respectively. Positioning components 342, 388, and 398, respectively, can be hardware circuits that are part of or coupled to processors 332, 384, and 394, respectively, that, when executed, cause UE 302, base station 304, and network entity 306 to perform the functionality described herein. In other aspects, the positioning components 342, 388, and 398 can be external to the processors 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 can be memory modules stored in the memories 340, 386, and 396, respectively, which, when executed by the processors 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. Figure 3A Possible locations are illustrated for a positioning component 342, which can be, for example, part of one or more WWAN transceivers 310, memory 340, one or more processors 332, or any combination thereof, or can be a stand-alone component. Figure 3B Possible locations are illustrated for a positioning component 388, which can be, for example, part of one or more WWAN transceivers 350, memory 386, one or more processors 384, or any combination thereof, or can be a stand-alone component. Figure 3C Possible locations are illustrated for a positioning component 398, which can be, for example, part of one or more network transceivers 390, memory 396, one or more processors 394, or any combination thereof, or can be a stand-alone component.

[0076] The UE 302 may include one or more sensors 344 coupled to one or more processors 332 to provide a means for sensing or detecting movement and / or orientation information that is independent of motion data derived from signals received by one or more WWAN transceivers 310, one or more short-range wireless transceivers 320, and / or satellite signal receivers 330. By way of example, the sensor(s) 344 may include an accelerometer (e.g., a microelectromechanical system (MEMS) device), a gyroscope, a geomagnetic sensor (e.g., a compass), an altimeter (e.g., a barometric altimeter), and / or any other type of motion detection sensor. Furthermore, the sensor(s) 344 may include multiple different types of devices and combine their outputs to provide motion information. For example, the sensor(s) 344 may use a combination of a multi-axis accelerometer and an orientation sensor to provide the ability to calculate position in a two-dimensional (2D) and / or three-dimensional (3D) coordinate system.

[0077] Additionally, the UE 302 includes a user interface 346 that provides a means for providing indications to the user (e.g., audible and / or visual indications) and / or for receiving user input (e.g., upon user actuation of a sensing device such as a keypad, touch screen, microphone, etc.). Although not shown, the base station 304 and the network entity 306 may also include a user interface.

[0078] Referring in more detail to the one or more processors 384, in the downlink, IP packets from the network entity 306 may be provided to the processor 384. The one or more processors 384 may implement functionality for the RRC layer, the Packet Data Convergence Protocol (PDCP) layer, the Radio Link Control (RLC) layer, and the Medium Access Control (MAC) layer. One or more processors 384 may provide RRC layer functionality associated with system information (e.g., Master Information Block (MIB), System Information Block (SIB)) broadcast, 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 delivery of upper layer PDUs, error correction through automatic repeat request (ARQ), concatenation, segmentation and reassembly of RLC service data units (SDUs), resegmentation 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.

[0079] Transmitter 354 and receiver 352 may implement Layer 1 (L1) functionality associated with various signal processing functions. Layer 1, including the physical (PHY) layer, may include error detection on the transport channel, forward error correction (FEC) coding / decoding of the transport channel, interleaving, rate matching, mapping onto the physical channel, modulation / demodulation of the physical channel, and MIMO antenna processing. Transmitter 354 handles the mapping to the signal constellation 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 orthogonal frequency division multiplexing (OFDM) subcarriers, multiplexed with reference signals (e.g., pilots) 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 generate multiple spatial streams. Channel estimates from a channel estimator may be used to determine the coding and modulation schemes and for spatial processing. The channel estimates 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 the corresponding spatial stream for transmission.

[0080] At UE 302, receiver 312 receives a signal via its corresponding antenna(s) 316. Receiver 312 recovers the information modulated onto the RF carrier and provides the information to one or more processors 332. Transmitter 314 and receiver 312 implement Layer 1 functionality associated with various signal processing functions. Receiver 312 may perform spatial processing on the information to recover any spatial streams destined for UE 302. If there are multiple spatial streams destined for UE 302, they may be combined by receiver 312 into a single OFDM symbol stream. 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 includes a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, as well as the reference signal, are recovered and demodulated by determining the signal constellation point most likely transmitted by base station 304. These soft decisions may be based on channel estimates calculated by a channel estimator. These soft decisions are then decoded and deinterleaved to recover the data and control signals originally transmitted on the physical channel by the base station 304. These data and control signals are then provided to one or more processors 332 that implement layer 3 (L3) and layer 2 (L2) functionality.

[0081] In the uplink, one or more processors 332 provide demultiplexing between transport channels and logical channels, packet reassembly, code decoding, header decompression, and control signal processing to recover IP packets from the core network. One or more processors 332 are also responsible for error detection.

[0082] Similar to the functionality described in conjunction with downlink transmissions performed by the base station 304, the one or more processors 332 provide RRC layer functionality associated with system information (e.g., MIB, SIB) acquisition, RRC connection, and measurement reporting; PDCP layer functionality associated with header compression / decompression and security (ciphering, deciphering, integrity protection, integrity verification); RLC layer functionality associated with delivery of upper layer PDUs, error correction through ARQ, concatenation, segmentation and reassembly of RLC SDUs, resegmentation 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.

[0083] Channel estimates derived by a channel estimator from a reference signal or feedback transmitted by base station 304 may be used by transmitter 314 to select appropriate coding and modulation schemes, and to facilitate spatial processing. The spatial streams generated by transmitter 314 may be provided to different antenna(s) 316. Transmitter 314 may modulate an RF carrier with the corresponding spatial stream for transmission.

[0084] Uplink transmissions are processed at the base station 304 in a manner similar to that described with respect to the receiver functionality at the UE 302. The receiver 352 receives the signal through its respective antenna(s) 356. The receiver 352 recovers information modulated onto the RF carrier and provides the information to one or more processors 384.

[0085] In the uplink, one or more processors 384 provide demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, and control signal processing to recover IP packets from UE 302. The IP packets from one or more processors 384 may be provided to the core network. One or more processors 384 are also responsible for error detection.

[0086] For convenience, UE 302, base station 304 and / or network entity 306 may be configured to Figure 3A 、 3Band 3C are shown as including various components that can be configured according to the various examples described herein. However, it will be appreciated that the illustrated components may have different functionality in different designs. Specifically, Figures 3A to 3C The various components in are optional in alternative configurations, and various aspects include configurations that may vary due to design choice, cost, use of the device, or other considerations. For example, in Figure 3A In the case of , a specific implementation of UE 302 may omit WWAN transceiver 310 (e.g., a wearable device or tablet or PC or laptop may have Wi-Fi and / or Bluetooth capabilities but no cellular capabilities), or may omit short-range wireless transceiver 320 (e.g., only cellular, etc.), or may omit satellite signal receiver 330, or may omit sensor 344, etc. In another example, in Figure 3B In the case of a wireless network, a particular implementation of the base station 304 may omit the WWAN transceiver 350 (e.g., a Wi-Fi "hotspot" access point without cellular capabilities), or may omit the short-range wireless transceiver 360 (e.g., cellular only, etc.), or may omit the satellite receiver 370, etc. For the sake of brevity, illustrations of various alternative configurations are not provided herein, but will be readily apparent to those skilled in the art.

[0087] Various components of the UE 302, base station 304, and network entity 306 may be communicatively coupled to one another over data buses 334, 382, ​​and 392, respectively. In an aspect, the data buses 334, 382, ​​and 392 may form or be part of communication interfaces for the UE 302, base station 304, and network entity 306, respectively. For example, where different logical entities are implemented in the same device (e.g., gNB and location server functionality are incorporated into the same base station 304), the data buses 334, 382, ​​and 392 may provide communication therebetween.

[0088] Figure 3A 、 3B The components of 3C can be implemented in various ways. In some implementations, Figure 3A 、 3BEach component of blocks 310 through 346 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). Each circuit may use and / or include at least one memory component for storing information or executable code used by the circuit to provide such functionality. For example, some or all of the functionality represented by blocks 310 through 346 may be implemented by the processor and memory components of the UE 302 (e.g., by executing appropriate code and / or by appropriately configuring the processor components). Similarly, some or all of the functionality represented by blocks 350 through 388 may be implemented by the processor and memory components of the base station 304 (e.g., by executing appropriate code and / or by appropriately configuring the processor components). Furthermore, some or all of the functionality represented by blocks 390 through 398 may be implemented by the processor and memory components of the network entity 306 (e.g., by executing appropriate code and / or by appropriately configuring the processor components). For simplicity, various operations, actions, and / or functions are described herein as being performed “by a UE,” “by a base station,” “by a network entity,” etc. However, as will be appreciated, such operations, actions, and / or functions may actually be performed by a specific component or combination of components of the UE 302, base station 304, network entity 306, etc., such as the processors 332, 384, 394, the transceivers 310, 320, 350, and 360, the memories 340, 386, and 396, the positioning components 342, 388, and 398, etc.

[0089] In some designs, the network entity 306 may be implemented as a core network component. In other designs, the network entity 306 may be distinct from the network operator or operation of the cellular network infrastructure (e.g., NG RAN 220 and / or 5GC 210 / 260). For example, the network entity 306 may be a component of a private network that may be configured to communicate with the UE 302 via the base station 304 or independently of the base station 304 (e.g., over a non-cellular communication link such as WiFi).

[0090] Figure 4 An example low intermediate frequency (IF) radio frequency front end (RFFE) receiver architecture 400 is illustrated in accordance with aspects of the present disclosure. The receiver architecture 400 is operable by Figure 3A 、 3B4 . An example of an architecture utilized by receiver(s) 312, 322, 352, and / or 362 in FIG. An electromagnetic RF signal is converted into an electrical current by antenna 402. The signal is passed through an RF band-select or bandpass filter (BPF) 404, which covers a wide frequency band to encompass all possible operating frequencies of the applicable standard. Bandpass filter 404 suppresses (attenuates) signals reaching antenna 402 that are outside the operating band. The filtered signal is then amplified by a low-noise amplifier (LNA) 406, which increases the signal power to a level sufficient for processing by mixer 408. Mixer 408 uses a signal generated by local oscillator 410 to down-convert the received signal into an IF signal. The IF signal is passed to image rejection filter 412, which only accepts signals within a predefined frequency band. The signal is then passed through low-pass filter 414 to further suppress out-of-band signals and mixing products. More specifically, low-pass filter 414 passes signals with frequencies below a selected cutoff frequency and suppresses (attenuates) signals with frequencies above the cutoff frequency. The resulting signal is then amplified by variable gain amplifier 416 and converted into a digital signal by analog-to-digital converter (ADC) 418. Specifically, the signal from variable gain amplifier 416 is an analog signal, meaning it is a continuous electromagnetic wave. ADC 418 samples this continuous wave signal and converts it into a discretized digital signal. The digital signal is then provided to the baseband circuitry for further processing.

[0091] In more detail, an ADC (e.g., ADC 418) works by sampling input values ​​at discrete intervals in time. Assuming the input is sampled at a rate higher than the Nyquist rate (defined as twice the highest frequency or bandwidth of interest), all frequencies in the signal can be reconstructed. If frequencies higher than half the Nyquist rate are sampled, these frequencies are incorrectly detected as lower frequencies, a process known as aliasing. Aliasing occurs because instantaneous sampling of a function twice or less per cycle results in missed cycles, and therefore incorrect lower frequencies appear. For example, a 2kHz sine wave sampled at 1.5kHz will be reconstructed as a 500Hz sine wave. To avoid aliasing, the input to the ADC is low-pass filtered (e.g., by low-pass filter 414) to remove frequencies higher than half the sampling rate. Low-pass filters are also referred to as anti-aliasing filters and are necessary for ADCs that process analog signals with higher frequency content. Aliasing and the Nyquist sampling rate are further described below.

[0092] Receiver architecture 400 is one example of a channel selection filter and any other architecture may be substituted. For example, a zero-IF receiver architecture may be utilized where an RF signal is down-converted to a baseband signal in a single or multiple steps.

[0093] Various frame structures may be used to support downlink and uplink transmissions between network nodes (eg, base stations and UEs). Figure 5 is a diagram 500 illustrating an example frame structure in accordance with aspects of the present disclosure. Other wireless communication technologies may have different frame structures and / or different channels.

[0094] LTE, and in some cases NR, utilizes OFDM on the downlink and single-carrier frequency division multiplexing (SC-FDM) on the uplink. However, unlike LTE, NR also has the option of using OFDM on the uplink. OFDM and SC-FDM divide the system bandwidth into multiple (K) orthogonal subcarriers, often referred to as tones, bins, etc. Each subcarrier can be modulated with data. Generally speaking, modulation symbols are sent in the frequency domain for OFDM and in the time domain for SC-FDM. The spacing between adjacent subcarriers can be fixed, and the total number of subcarriers (K) can depend on the system bandwidth. For example, the subcarrier spacing can be 15 kilohertz (kHz), and the minimum resource allocation (resource block) can be 12 subcarriers (or 180 kHz). Therefore, for system bandwidths of 1.25, 2.5, 5, 10, or 20 megahertz (MHz), the nominal FFT size can be 128, 256, 512, 1024, or 2048, respectively. The system bandwidth may be further divided into subbands. For example, a subband may cover 1.08 MHz (ie, 6 resource blocks), and there may be 1, 2, 4, 8, or 16 subbands for system bandwidths of 1.25, 2.5, 5, 10, or 20 MHz, respectively.

[0095] LTE supports a single parameter design (subcarrier spacing (SCS), symbol length, etc.). In contrast, NR may support multiple parameter designs (μ), for example, subcarrier spacings of 15 kHz (μ = 0), 30 kHz (μ = 1), 60 kHz (μ = 2), 120 kHz (μ = 3), and 240 kHz (μ = 4) or larger may be available. In each subcarrier spacing, there are 14 symbols per slot. For a 15 kHz SCS (μ = 0), there is one slot per subframe, 10 slots per frame, a slot duration of 1 millisecond (ms), a symbol duration of 66.7 microseconds (μs), and a maximum nominal system bandwidth (in MHz) of 50 with a 4K FFT size. For 30kHz SCS (μ=1), there are two slots per subframe, 20 slots per frame, the slot duration is 0.5ms, the symbol duration is 33.3μs, and the maximum nominal system bandwidth (in MHz) with a 4K FFT size is 100. For 60kHz SCS (μ=2), there are four slots per subframe, 40 slots per frame, the slot duration is 0.25ms, the symbol duration is 16.7μs, and the maximum nominal system bandwidth (in MHz) with a 4K FFT size is 200. For 120kHz SCS (μ=3), there are eight slots per subframe, 80 slots per frame, the slot duration is 0.125ms, the symbol duration is 8.33μs, and the maximum nominal system bandwidth (in MHz) with a 4K FFT size is 400. For 240kHz SCS (μ=4), there are 16 slots per subframe, 160 slots per frame, the slot duration is 0.0625ms, the symbol duration is 4.17μs, and the maximum nominal system bandwidth (in MHz) is 800 with 4K FFT size.

[0096] exist Figure 5 In the example of , a parameter design of 15 kHz is used. Thus, in the time domain, a 10 ms frame is divided into 10 equally sized subframes, each subframe is 1 ms, and each subframe includes one time slot. Figure 5 , time is represented horizontally (on the X-axis), where time increases from left to right, and frequency is represented vertically (on the Y-axis), where frequency increases (or decreases) from bottom to top.

[0097] A resource grid may be used to represent a time slot, each of which includes 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 a plurality of resource elements (REs). An RE may correspond to one symbol length in the time domain and one subcarrier in the frequency domain. Figure 5In the parameter design of

[15] , for a normal cyclic prefix, an RB may contain 12 consecutive subcarriers in the frequency domain and 7 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 6 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.

[0098] Some REs may carry reference (pilot) signals (RS). These reference signals may include positioning reference signals (PRS), tracking reference signals (TRS), phase tracking reference signals (PTRS), cell-specific reference signals (CRS), channel state information reference signals (CSI-RS), demodulation reference signals (DMRS), primary synchronization signals (PSS), secondary synchronization signals (SSS), synchronization signal blocks (SSBs), sounding reference signals (SRS), etc., depending on whether the illustrated frame structure is used for uplink or downlink communications. Figure 5 Example locations of REs carrying reference signals (labeled "R") are illustrated.

[0099] The set of resource elements (REs) used for PRS transmission is called a "PRS resource." A set of resource elements may span multiple PRBs in the frequency domain and N (such as one or more) consecutive symbols 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.

[0100] The transmission of PRS resources within a given PRB has a specific comb size (also referred to as "comb density"). The comb size 'N' represents the subcarrier spacing (or frequency / tone spacing) within each symbol of the PRS resource configuration. Specifically, for comb size 'N', the PRS is transmitted in every Nth subcarrier of a symbol of the PRB. For example, for comb-4, for each symbol of the PRS resource configuration, the REs corresponding to every fourth subcarrier (such as subcarriers 0, 4, and 8) are used to transmit the PRS of the PRS resource. Currently, comb sizes of comb-2, comb-4, comb-6, and comb-12 are supported for DL-PRS. Figure 5 An example PRS resource configuration for comb-6 (which spans 6 symbols) is illustrated. That is, the positions of the shaded REs (labeled "R") indicate the PRS resource configuration for comb-6.

[0101] Currently, DL-PRS resources can span 2, 4, 6, or 12 consecutive symbols within a slot using a full frequency-domain staggered pattern. DL-PRS resources can be allocated in any downlink or flexible (FL) symbol configured by higher layers in a slot. A constant energy per resource element (EPRE) may exist for all REs of a given DL-PRS resource. The following are symbol-by-symbol frequency offsets for comb sizes of 2, 4, 6, and 12 over 2, 4, 6, and 12 symbols: 2-symbol comb-2: {0,1}; 4-symbol comb-2: {0,1,0,1}; 6-symbol comb-2: {0,1,0,1,0,1}; 12-symbol comb-2: {0,1,0,1,0,1,0,1,0,1,0,1}; 4-symbol comb-4: {0,2,1,3}; 12-symbol comb-4: {0,2,1,3,0,2,1,3,0,2,1,3}; 6-symbol comb-6: {0,3,1,4,2,5}; 12-symbol comb-6: {0,3,1,4,2,5,0,3,1,4,2,5}; and 12-symbol comb-12: {0,6,3,9,1,7,4,10,2,8,5,11}.

[0102] A "PRS resource set" is a set of PRS resources used for transmission of a PRS signal, 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 specific TRP (identified by a TRP 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 (such as "PRS-ResourceRepetitionFactor") across all time slots. The periodicity is the time from the first repetition of a first PRS resource of a first PRS instance to the same first repetition of the same first PRS resource of the next PRS instance. The periodicity may have a length selected from: 2^μ*{4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 160, 320, 640, 1280, 2560, 5120, 10240} slots, where μ=0, 1, 2, 3. The repetition factor may have a length selected from {1, 2, 4, 6, 8, 16, 32} slots.

[0103] The PRS resource ID in a PRS resource set is associated with a single beam (or beam ID) transmitted from a single TRP (wherein a TRP may transmit one or more beams). That is, each PRS resource in a PRS resource set may be transmitted on a different beam, and thus, a "PRS resource" (or simply "resource") may also be referred to as a "beam." Note that this does not imply whether the UE knows the TRP and beam in which the PRS is transmitted.

[0104] A "PRS instance" or "PRS opportunity" is an instance of a periodically repeating time window (such as a group of one or more consecutive time slots) in which a PRS is expected to be transmitted. A PRS opportunity may also be referred to as a "PRS positioning opportunity," "PRS positioning instance," "positioning opportunity," "positioning instance," "positioning repetition," or simply "opportunity," "instance," or "repetition."

[0105] A "positioning frequency layer" (also referred to simply as a "frequency layer") is a collection of one or more PRS resource sets with the same values ​​for certain parameters across one or more TRPs. Specifically, the set of PRS resource sets has the same subcarrier spacing and cyclic prefix (CP) type (meaning that all parameter designs supported by the physical downlink shared channel (PDSCH) are also supported by PRS), the same point A, the same value for the downlink PRS bandwidth, the same starting PRB (and center frequency), and the same comb size. The point A parameter takes the value of the parameter "ARFCN-ValueNR" (where "ARFCN" stands for "Absolute Radio Frequency Channel Number") and is an identifier / code that specifies a pair of physical radio channels used for transmission and reception. The downlink PRS bandwidth can have a granularity of 4 PRBs, with a minimum value of 24 PRBs and a maximum value of 272 PRBs. Currently, up to four frequency layers are defined, and up to two PRS resource sets can be configured per frequency layer per TRP.

[0106] The concept of frequency layers is somewhat similar to the concepts of component carriers and bandwidth parts (BWPs), but the difference is that component carriers and BWPs are used by one base station (or macrocell base station and small cell base station) to transmit data channels, while frequency layers are used by several (often three or more) base stations to transmit PRSs. The UE can indicate the number of frequency layers it can support when it sends its positioning capabilities to the network (such as during an LTE Positioning Protocol (LPP) session). For example, the UE can indicate whether it can support one or four positioning frequency layers.

[0107] Note that the terms "positioning reference signal" and "PRS" generally refer to specific reference signals used for positioning in NR and LTE systems. However, as used herein, the terms "positioning reference signal" and "PRS" may also refer to any type of reference signal that can be used for positioning, such as, but not limited to, PRS, TRS, PTRS, CRS, CSI-RS, DMRS, PSS, SSS, SSB, SRS, UL-PRS, etc., as defined in LTE and NR. Furthermore, the terms "positioning reference signal" and "PRS" may refer to either downlink or uplink positioning reference signals, unless otherwise indicated by the context. If further distinction is needed between the types of PRS, downlink positioning reference signals may be referred to as "DL-PRS," while uplink positioning reference signals (e.g., positioning SRS, PTRS) may be referred to as "UL-PRS." Furthermore, for signals that can be transmitted in both the uplink and downlink (e.g., DMRS, PTRS), these signals may be prepended with "UL" or "DL" to distinguish their direction. For example, "UL-DMRS" may be distinguished from "DL-DMRS."

[0108] Figure 6 Figure 600 illustrates an example radio frequency (RF) signal processing procedure according to various aspects of the present disclosure. To identify the time of arrival (ToA) of an RF signal (e.g., a positioning reference signal (PRS)), a receiver (e.g., a UE) first buffers and then jointly processes all resource elements (REs) on the channel from which the transmitter (e.g., a base station) transmitted the RF signal. The receiver then performs an inverse Fourier transform (FFT) to convert the received RF signal to the time domain. This conversion of the received RF signal to the time domain is known as an estimate of the channel energy response (CER) or channel impulse response (CIR). The CER shows peaks in the channel over time, and therefore the earliest "significant" peak should correspond to the ToA of the RF signal. Typically, the receiver will use a noise-related quality threshold to filter out false local peaks, thereby assuming that the significant peaks on the channel are correctly identified. For example, the receiver may select the ToA estimate that is the earliest local maximum of the CER that is at least 'X' decibels (dB) above the median CER and at most 'Y' dB below the main peak on the channel.

[0109] Therefore, reference Figure 6In a fast Fourier transform (FFT) stage 610, a receiver (e.g., any UE described herein) receives / measures and buffers a time-domain RF signal (e.g., a PRS) and converts it into a frequency-domain signal. In a correlation stage 620, the receiver generates a frequency-domain channel impulse response from the frequency-domain signal based on a descrambling sequence. In an inverse fast Fourier transform (IFFT) stage 630, the receiver generates a time-domain channel impulse response from the frequency-domain channel impulse response output by the correlation stage 620. In an earliest peak detection stage 640, the receiver generates a detection indication and a ToA of the time-domain RF signal received in the FFT stage 610 based on the time-domain channel impulse response received from the IFFT stage 630.

[0110] In the case where the receiving party is a UE, the UE may receive the time-domain RF signal at one or more antennas 316. Subsequent stages (i.e., FFT stage 610, correlation stage 620, IFFT stage 630, earliest peak detection stage 640) may be performed by one or more receivers 312, one or more WWAN transceivers 310, and / or one or more processors 332, depending on the hardware implementation of the UE. Similarly, in the case where the receiving party is a base station, the base station may receive the time-domain RF signal at one or more antennas 356. Subsequent stages may be performed by one or more receivers 352, one or more WWAN transceivers 350, and / or one or more processors 384, depending on the hardware implementation of the base station.

[0111] The accuracy requirements for locating UEs (whether indoors or outdoors) are becoming increasingly demanding, requiring increasingly advanced hardware on the UE side. However, for at least some industrial scenarios, there is a challenging trade-off between delivering top-tier performance and potentially low-end UE modems due to cost and economies of scale.

[0112] A key resource in delivering positioning accuracy is signal bandwidth, which allows for higher resolution ranging, which translates into higher positioning accuracy. Figure 7 700 is a graph illustrating the relationship between transmission bandwidth and measurement accuracy according to aspects of the present disclosure. Graph 700 includes an x-axis corresponding to an offset (e.g., measured in meters (m)) and a y-axis corresponding to a measurement amplitude. The measurement can be a measurement of the correlation between a reference signal (e.g., a PRS) received at a UE and a local image of the reference signal transmitted by a base station (or more specifically, a TRP). A peak correlation (e.g., having an amplitude greater than 0.8, 0.9, or some other suitable value) can correspond to a particular offset.

[0113] Graph 700 includes measurements associated with different transmission bandwidths, specifically 50 MHz measurement 705, 100 MHz measurement 710, 200 MHz measurement 720, and 400 MHz measurement 740. Figure 7 As understood in the preceding text, narrower frequency bands (50 MHz measurement 705 being the narrowest) have peaks that may potentially correspond to a wider range of excursions. For example, if an amplitude of 0.8 or greater is considered a peak, the peak associated with the 50 MHz measurement 705 is associated with an excursion in the range of approximately -2 m to +2 m. In contrast, the peak associated with the 100 MHz measurement 710 may be associated with an excursion in the range of approximately -1 m to +1 m. Wider bandwidths (including the 200 MHz measurement 720 and the 400 MHz measurement 740) correspond to increasingly accurate measurements and narrower ranges (-0.5 m to +0.5 m and -0.25 m to +0.25 m, respectively).

[0114] Figure 7 The relationship depicted in indicates that wider bandwidth is associated with more accurate measurements. However, measuring wider bandwidths requires stronger processing capabilities on the UE side. Accordingly, the present disclosure provides techniques for retaining the positioning accuracy brought by using larger (wider) bandwidth signals while utilizing limited modem capabilities. The present invention also provides for ADCs (e.g., Figure 4 The benefit of power reduction of the ADC 418 in FIG. 4 is that power consumption increases linearly with sampling rate and thus reducing the sampling rate as described herein reduces the power consumption of the ADC.

[0115] For any band-limited continuous signal x(t) with a unilateral bandwidth (B), the Nyquist sampling theorem states that, from s Perfect signal reconstruction is possible in a sample sequence obtained with >2B. This is due to the phenomenon of "aliasing", which causes the spectrum of the sampled signal to become a continuous signal spectrum with an interval of f s A series of copies.

[0116] In more detail, when a continuous function x(t) is moving at a constant rate (f s samples / second), there are an infinite number of other continuous functions that fit the same sample set. However, only one of them is band-limited to f s cycles / second (Hz), which means that its Fourier transform X(f) is half for all |f| ≥ 1 / 2f s. If the original function x(t) is limited to 1 / 2f s , then it is called the Nyquist criterion. In terms of the bandwidth (B) of the function itself, the Nyquist criterion is often expressed as f s>2B, where 2B is called the Nyquist rate for a function of bandwidth B. When the Nyquist criterion is not satisfied (i.e., B>1 / 2f s ), a condition known as aliasing occurs, which results in some unavoidable differences between x(t) and the reconstructed function with a smaller bandwidth.

[0117] Aliasing is the effect that causes different signals to become indistinguishable (or become aliases of each other) when sampled. Aliasing also often refers to the distortion or artifacts that occur when the signal reconstructed from the samples differs from the original continuous signal. Aliasing is usually achieved by applying a low-pass filter (e.g., a filter) to the input signal before sampling and when converting the signal from a higher sampling rate to a lower sampling rate. Figure 4 A low-pass filter 414 in the filter or an anti-aliasing filter (AAF) is used to avoid aliasing.

[0118] Regarding aliasing and the Nyquist sampling theorem, real signals have finite duration and, as defined in terms of the Fourier transform, their frequency content has no upper bound. Thus, when sampling such functions, some amount of aliasing will always occur. Functions whose frequency content is bounded (band-limited) have infinite duration in the time domain. If sampling is done at a high enough rate, specifically f s >2B, then the original function can theoretically be perfectly reconstructed from an infinite set of samples.

[0119] The actual assumption behind the Nyquist sampling theorem is that the spectrum of the original signal is "full." That is, the signal is assumed to occupy the entire available spectrum (e.g., the entire system bandwidth). If the signal is "sparse," meaning only a portion of the available spectrum is used, as in the case of comb sizes greater than comb-1, aliasing can be controlled to the receiver's advantage, as described below.

[0120] The present disclosure provides techniques for designing PRS spectrum occupancy to enable a sub-Nyquist sampling receiver to efficiently process the PRS. A "sub-Nyquist" sampling receiver is a receiver (e.g., receiver(s) 312) whose ADC operates at a frequency that is less than the Nyquist rate (2B) of the bandwidth of the transmitted PRS. In one aspect, the TRP may transmit the PRS over a bandwidth that is larger than the operating bandwidth of the UE (comprising a certain number of tones). The TRP may signal to the UE the mapping between the transmitted physical tones (transmitted in the larger bandwidth) and the received physical tones (i.e., received in the operating bandwidth of the UE). More specifically, the mapping will indicate which tones are occupied and which are not. The UE may use the mapping information to descramble the PRS in the appropriate order (as described above with reference to FIG. Figure 6 as described) and reorders the tones for further processing in time or frequency, thereby utilizing a bandwidth much larger than the normal operating bandwidth of the UE.

[0121] Figure 8 A comparison between sampling an RF signal (e.g., a PRS) at its Nyquist rate and at a sub-Nyquist rate of the RF signal is illustrated in accordance with aspects of the present disclosure. Figure 8 In , each block represents frequency domain samples of the RF signal, such as samples of one or more adjacent tones or PRBs. The direct current (DC) offset (reference point of the RF signal) is illustrated with a dashed line and may be a specific tone in the RF signal bandwidth to which the samples of the RF signal may be compared. Parameter R S is the sampling rate, and the parameter N is the folding factor. The folding factor indicates the period (here, the period in the frequency domain) over which samples of the RF signal exhibit symmetrical behavior. Figure 8 In the example shown in Figure 2, the RF signal exhibits this symmetry over the folding factor N.

[0122] Graph 800 is a graph of the Nyquist rate N*R S The baseband representation of the sampled RF signal is shown in Figure 850, while the graph 850 is a sub-Nyquist rate R S Baseband representation of a sampled RF signal. Due to the higher sampling rate represented by diagram 800, the RF signal is sampled every 5th block (shaded) at the folding factor N, with two blocks on each side of the DC offset. Similarly, due to the lower sampling rate represented by diagram 850, the RF signal is sampled in every block. More specifically, by sampling at a higher rate (specifically, N*R S ), the receiver will sample at a folding factor N that does not include any portion of the RF signal (blank blocks). In contrast, by sampling at a lower rate (specifically R S ), the receiver will obtain N times fewer samples, resulting in only the frequency blocks (e.g., tones, PRBs) containing the RF signal being sampled. However, this will also lead to aliasing. Specifically, only the four blocks in block 860 near the DC offset correspond to the actual RF signal and will pass through the low-pass filter ( Figure 8 is abbreviated as "LPF" and it may correspond to Figure 4 The remaining blocks within the period of folding factor N are aliases of the four blocks in block 860.

[0123] If you can Figure 8 As seen in Figure 1, if the UE uses a different DC offset than the expected DC offset (indicated by the dashed line), it will still be able to access the full RF signal. However, the UE will need to rotate the mapping accordingly before performing the IFFT (e.g., for the time-based earliest arriving path (EAP)). This means that the base station signaling containing the frequency tone map will also need to specify the frequency at which the UE expects the DC offset to be placed.

[0124] In order to make the UE follow the Anaquist rate RS To correctly sample the RF signal, the UE needs to know the parameters N and R S In addition, TRP needs to configure the RF signal so that it can be correctly sampled at the configured sub-Nyquist rate. Parameters N and R S These parameters may be set in the applicable standard or signaled to the UE by the TRP. Alternatively, the UE may be able to derive these parameters from the tone map provided by the TRP. For example, if the RF signal is a PRS, then based on the PRS resource configuration received from the TRP, the UE may be able to determine the folding factor N and the sampling rate R. S , which will enable the UE to operate at the sub-Nyquist rate R S To sample PRS.

[0125] The configuration from the TRP may provide various information. As a first option, the configuration may indicate a PRS resource spanning approximately N*273 PRBs (e.g., N component carriers, where N is the folding factor and each component carrier includes 273 PRBs; however, note that not all N component carriers need to be occupied). The configuration may further indicate the absolute starting point of the N*273 PRBs in the frequency domain. The N*273 PRBs may be part of a frequency layer with a similarly large PRS resource spanning the TRP.

[0126] As a second option, the configuration may indicate N PRS resources, where N is the folding factor and each PRS resource is defined on a different frequency layer. In this case, additional configuration will need to be provided to enable the UE to perform the association between the N PRS resources and the frequency layers. This option may be preferred over the first option in cases where it is preferred not to define large PRS resources (e.g., N*273 PRBs). In addition, this allows lower-capability UEs to process a layer without performing folding by concentrating their operating frequencies around that layer.

[0127] Figure 8 The examples are for designs that define different blocks of contiguous PRBs, for example. However, in other aspects, blocks of non-contiguous PRBs may be folded together or even interleaved subcarrier sets may be folded together, such as Figure 9 As explained in Figure 9 In the example of FIG, three non-contiguous subcarrier sets (each spanning 100 MHz) are folded together. Specifically, the first subcarrier set 910 and the third subcarrier set 930 are folded with the second subcarrier set 920. Figure 9 The arrows in indicate how the receiver samples the subcarriers at a sub-Nyquist rate. Figure 9The scenario illustrated in will guarantee better time resolution since it evenly spaces the carriers. The benefit of staggering resource blocks to reduce the number of contiguous nulls is that legacy UEs can still use a portion of the allocated PRS and perform traditional PRS processing without utilizing sub-Nyquist sampling.

[0128] In this design, the UE's bandpass filter (e.g. Figure 4 The bandpass filter 404 in the UE) will need to cover the bandwidth occupied by the TRP rather than the effective low-pass filter bandwidth of the UE before converting to IF. Figure 8 The sampling (performed by mixer 408 in the UE) and image rejection filtering (e.g., by image rejection filter 412) also need to cover the entire bandwidth (i.e., the bandwidth occupied by the TRP). After the above sampling (performed by the UE's ADC), the difference between the bandwidth used by the TRP and the bandwidth used by the UE will be completely transparent to the rest of the UE's receiver circuitry.

[0129] It should also be noted that for a folding factor N, the signal-to-noise ratio (SNR) will also degrade by 10log10(N) compared to reception at the full bandwidth (using Nyquist sampling) due to the noise folding. In addition, a folding factor N will be required for each "part" (e.g. Figure 8 The four block groups in the [4] are used to design appropriate guard tones to account for potential inter-carrier interference.

[0130] Figure 10 Illustrated is an example wireless communication method 1000 in accordance with aspects of the present disclosure. In an aspect, the method 1000 may be performed by a UE (eg, any UE described herein).

[0131] At 1010, a bandpass filter (eg, Figure 4 4. The bandpass filter 404 in FIG. 4 is configured to receive an analog RF signal (e.g., a PRS) having a first bandwidth (e.g., an operating bandwidth of a TRP transmitting the analog RF signal) associated with a first sampling rate (e.g., a Nyquist rate of the first bandwidth). In one aspect, the bandpass filter 404 can be considered a means for performing this operation.

[0132] At 1020, the UE's ADC (e.g., Figure 4 The ADC 418 (in the embodiment of the present invention) samples the analog RF signal at a second sampling rate (e.g., a sub-Nyquist rate) to generate a digital RF signal representing the analog RF signal. The ADC may operate at a second bandwidth lower than the first bandwidth. The second sampling rate may be the inverse of the first sampling rate multiplied by a folding factor (e.g., N) of the first bandwidth. In one aspect, the ADC 418 may be considered as a means for performing this operation.

[0133] At 1030, the ADC outputs the digital RF signal to the baseband processor of the UE. In one aspect, the ADC 418 can be considered as a means for performing this operation. The digital RF signal can be further processed, for example, for positioning purposes.

[0134] As will be appreciated, technical advantages of method 1000 include preserving the resolution capability afforded by large bandwidth signals while utilizing limited modem capabilities, and reducing ADC power consumption which increases linearly with sampling rate.

[0135] In the above detailed description, it can be seen that different features are grouped together in each example. This disclosure should not be understood as an intention that the example clauses have more features than the features explicitly mentioned in each clause. On the contrary, various aspects of the present disclosure may include less than all the features of the disclosed individual example clauses. Therefore, the attached clauses should be considered to be incorporated into this description, wherein each clause itself may be a separate example. Although each dependent clause can be referenced in each clause in a specific combination with one of the other clauses, the (all) aspects of the dependent clause are not limited to this specific combination. It will be appreciated that other example clauses may also include a combination of the dependent clause (all) aspects with the subject matter of any other dependent clause or independent clause or a combination of any feature with other dependent and independent clauses. The various aspects disclosed herein explicitly include these combinations, unless explicitly expressed or can be easily inferred that a specific combination is not intended (for example, contradictory aspects, such as defining an element as an insulator and a conductor at the same time). In addition, it is also intended that various aspects of a clause can be included in any other independent clause, even if the clause is not directly subordinate to the independent clause.

[0136] Implementation examples are described in the following numbered clauses.

[0137] Clause 1. A wireless communication method performed by a user equipment (UE), comprising: receiving an analog radio frequency (RF) signal having a first bandwidth associated with a first sampling rate at a bandpass filter of a radio frequency front end (RFFE) of the UE, the analog RF signal including a positioning reference signal (PRS); sampling the analog RF signal at a second sampling rate by an analog-to-digital converter (ADC) of the UE to generate a digital RF signal representing the analog RF signal, wherein the ADC operates at a second bandwidth lower than the first bandwidth, and wherein the second sampling rate is a reciprocal of a folding factor of the first bandwidth multiplied by the first sampling rate; and outputting the digital RF signal to a baseband processor of the UE.

[0138] Clause 2. The method of clause 1, wherein: the first sampling rate is a Nyquist sampling rate for the first bandwidth, and the second sampling rate is a sub-Nyquist sampling rate for the first bandwidth.

[0139] Clause 3. The method of any one of clauses 1 to 2, wherein: the first sampling rate is And the second sampling rate is Where N is the folding factor of the first bandwidth and R S is the sampling rate.

[0140] Clause 4. The method of any of clauses 1 to 3, further comprising: receiving a mapping between frequency tones at which the analog RF signal is transmitted at a first bandwidth and frequency tones at which the analog RF signal is received at a second bandwidth.

[0141] Clause 5. The method of clause 4, wherein sampling the analog RF signal is based on the mapping.

[0142] Clause 6. The method of clause 5, wherein the sampling is based on the mapping and comprises: the UE determining a folding factor for the first bandwidth based on the mapping.

[0143] Clause 7. The method of any one of clauses 1 to 6, wherein the samples of the analog RF signal are centered about a direct current (DC) offset.

[0144] Clause 8. The method of clause 7, further comprising: receiving an indication of a reference frequency tone at which the DC offset is to be located from a transmit receive point (TRP) that transmits the analog RF signal.

[0145] Clause 9. The method of any one of clauses 1 to 8, wherein: the analog RF signal comprises one PRS resource spanning N component carriers, N being a folding factor of the first bandwidth, and the one PRS resource is part of one positioning frequency layer.

[0146] Clause 10. The method of any one of clauses 1 to 8, wherein: the analog RF signal comprises N PRS resources, N being a folding factor of the first bandwidth, and each of the N PRS resources is defined on a different positioning frequency layer.

[0147] Clause 11. The method of any one of clauses 1 to 10, further comprising: folding multiple blocks of contiguous frequency tones or physical resource blocks (PRBs) carrying the analog RF signal, wherein the sampling comprises sampling the folded multiple blocks of contiguous frequency tones or PRBs carrying the analog RF signal.

[0148] Clause 12. The method of any one of clauses 1 to 11, further comprising: folding multiple blocks of non-contiguous frequency tones or PRBs carrying the analog RF signal, wherein the sampling comprises sampling the folded multiple blocks of non-contiguous frequency tones or PRBs carrying the analog RF signal.

[0149] Clause 13. The method of any one of clauses 1 to 12, further comprising: folding a plurality of interleaved sets of subcarriers carrying the analog RF signal, wherein the sampling comprises sampling the folded sets of interleaved subcarriers carrying the analog RF signal.

[0150] Clause 14. The method of any one of clauses 1 to 13, wherein: the first bandwidth comprises an operating bandwidth of the TRP transmitting the analog RF signal, and the second bandwidth comprises an operating bandwidth of the UE.

[0151] Clause 15. The method of clause 14, wherein the bandpass filter operates at an operating bandwidth of the TRP.

[0152] Clause 16. An apparatus comprising: a memory, at least one transceiver, and at least one processor communicatively coupled to the memory and the at least one transceiver, the memory, the at least one transceiver, and the at least one processor configured to perform the method of any one of clauses 1 to 15.

[0153] Clause 17. An apparatus comprising means for performing the method of any one of clauses 1 to 15.

[0154] Clause 18. A non-transitory computer-readable medium storing computer-executable instructions, the computer-executable instructions comprising at least one instruction for causing a computer or processor to perform the method of any of Clauses 1 to 15.

[0155] Additional implementation examples are described in the following numbered clauses.

[0156] Clause 1. A wireless communication method performed by a user equipment (UE), comprising: receiving an analog radio frequency (RF) signal having a first bandwidth associated with a first sampling rate at a bandpass filter of a radio frequency front end (RFFE) of the UE, the analog RF signal including a positioning reference signal (PRS); sampling the analog RF signal at a second sampling rate by an analog-to-digital converter (ADC) of the UE to generate a digital RF signal representing the analog RF signal, wherein the ADC operates at a second bandwidth lower than the first bandwidth, and wherein the second sampling rate is a reciprocal of a folding factor of the first bandwidth multiplied by the first sampling rate; and outputting the digital RF signal to a baseband processor of the UE.

[0157] Clause 2. The method of clause 1, wherein: the first sampling rate is a Nyquist sampling rate for the first bandwidth, and the second sampling rate is a sub-Nyquist sampling rate for the first bandwidth.

[0158] Clause 3. The method of any one of clauses 1 to 2, wherein: the first sampling rate is N*RS, and the second sampling rate is RS, where N is the folding factor of the first bandwidth and RS is the sampling rate.

[0159] Clause 4. The method of any of clauses 1 to 3, further comprising: receiving a mapping between frequency tones at which the analog RF signal is transmitted at a first bandwidth and frequency tones at which the analog RF signal is received at a second bandwidth.

[0160] Clause 5. The method of clause 4, wherein sampling the analog RF signal is based on the mapping.

[0161] Clause 6. The method of clause 5, wherein sampling the analog RF signal based on the mapping comprises: determining a folding factor for the first bandwidth based on the mapping.

[0162] Clause 7. The method of any one of clauses 4 to 6, wherein the samples of the analog RF signal are centered about a direct current (DC) offset.

[0163] Clause 8. The method of clause 7, further comprising: receiving an indication of a reference frequency tone at which the DC offset is to be located from a transmit receive point (TRP) that transmits the analog RF signal.

[0164] Clause 9. The method of any one of clauses 1 to 8, wherein: the analog RF signal comprises one PRS resource spanning N component carriers, N being a folding factor of the first bandwidth, and the one PRS resource is part of one positioning frequency layer.

[0165] Clause 10. The method of any one of clauses 1 to 8, wherein: the analog RF signal comprises N PRS resources, N being a folding factor of the first bandwidth, and each of the N PRS resources is defined on a different positioning frequency layer.

[0166] Clause 11. A method as described in any of clauses 1 to 10, further comprising: folding multiple blocks of adjacent frequency tones or physical resource blocks (PRBs) carrying the analog RF signal, wherein sampling the analog RF signal includes sampling the folded multiple blocks of adjacent frequency tones or PRBs carrying the analog RF signal.

[0167] Clause 12. The method of any one of clauses 1 to 10, further comprising: folding multiple blocks of non-contiguous frequency tones or PRBs carrying the analog RF signal, wherein sampling the analog RF signal comprises sampling the folded multiple blocks of non-contiguous frequency tones or PRBs carrying the analog RF signal.

[0168] Clause 13. The method of any one of clauses 1 to 10, further comprising: folding a plurality of interleaved sets of subcarriers carrying the analog RF signal, wherein sampling the analog RF signal comprises sampling the folded set of interleaved subcarriers carrying the analog RF signal.

[0169] Clause 14. The method of any one of clauses 1 to 13, wherein: the first bandwidth comprises an operating bandwidth of the TRP transmitting the analog RF signal, and the second bandwidth comprises an operating bandwidth of the UE.

[0170] Clause 15. The method of clause 14, wherein the bandpass filter operates at an operating bandwidth of the TRP.

[0171] Clause 16. An apparatus comprising: a memory, at least one transceiver, and at least one processor communicatively coupled to the memory and the at least one transceiver, the memory, the at least one transceiver, and the at least one processor configured to perform the method of any one of clauses 1 to 15.

[0172] Clause 17. An apparatus comprising means for performing the method of any of clauses 1 to 15.

[0173] Clause 18. A non-transitory computer-readable medium storing computer-executable instructions, the computer-executable instructions comprising at least one instruction for causing a computer or processor to perform the method of any of Clauses 1 to 15.

[0174] Those skilled 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 referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0175] In addition, those skilled in the art will appreciate that the various illustrative logic blocks, modules, circuits, and algorithmic steps described in conjunction with the aspects disclosed herein can be implemented as electronic hardware, computer software, or a combination of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described above in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system. A skilled person may implement the described functionality in different ways for each specific application, but such implementation decisions should not be interpreted as causing a departure from the scope of this disclosure.

[0176] The various illustrative logical blocks, modules, and circuits described in conjunction with the various aspects disclosed herein may be implemented or executed with a general purpose processor, a digital signal processor (DSP), an ASIC, a field programmable gate array (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, such as 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.

[0177] The methods, sequences and / or algorithms described in conjunction with the various aspects disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. The 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, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An example storage medium is coupled to the processor so that the processor can read and write information from / to the storage medium. In an alternative, the storage medium may be integrated into the processor. The processor and storage medium may reside in an ASIC. The ASIC may reside in a user terminal (e.g., UE). In an alternative, the processor and storage medium may reside in the user terminal as discrete components.

[0178] 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 via a computer-readable medium as one or more instructions or code. Computer-readable media includes both computer storage media and communication media, including any medium that facilitates the transfer of a computer program from one location to another. A storage medium may be any available medium that can be accessed by a computer. By way of example and not limitation, such computer-readable media may include 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. Similarly, any connection is also properly referred to as 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 microwaves, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwaves are included in the definition of medium. As used herein, disk and disc include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc, where disks typically 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.

[0179] Although the foregoing disclosure shows illustrative aspects of the present disclosure, it should be noted that various changes and modifications may be made therein without departing from the scope of the present disclosure as defined by the appended claims. The functions, steps, and / or actions in the method claims according to the various aspects of the present disclosure described herein do not have to be performed in any particular order. Furthermore, although elements of the present disclosure may be described or claimed in the singular, the plural is contemplated unless limitation to the singular is explicitly stated.

Claims

1. A wireless communication method performed by a user equipment (UE), comprising: receiving, at a bandpass filter of a radio frequency front end (RFFE) of the UE, an analog radio frequency (RF) signal having a first bandwidth associated with a first sampling rate, the analog RF signal including a positioning reference signal (PRS); receiving a mapping between frequency tones for transmitting the analog RF signal at the first bandwidth and frequency tones for receiving the analog RF signal at a second bandwidth lower than the first bandwidth; sampling the analog RF signal at a second sampling rate by an analog-to-digital converter (ADC) of the UE to generate a digital RF signal representative of the analog RF signal, wherein the ADC operates at the second bandwidth, and wherein the second sampling rate is a reciprocal of the first sampling rate multiplied by a folding factor of the first bandwidth; as well as The digital RF signal is output to a baseband processor of the UE.

2. The method of claim 1, wherein: The first sampling rate is the Nyquist sampling rate of the first bandwidth, and The second sampling rate is a sub-Nyquist sampling rate of the first bandwidth.

3. The method of claim 1, wherein: The first sampling rate is N*R S ,and The second sampling rate is R S , where N is the folding factor of the first bandwidth and R S is the sampling rate. The method of claim 1 , wherein sampling the analog RF signal is based on the mapping.

5. The method of claim 4 , wherein sampling the analog RF signal based on the mapping comprises: The folding factor for the first bandwidth is determined based on the mapping.

6. The method of claim 1, wherein the samples of the analog RF signal are centered about a direct current (DC) offset.

7. The method of claim 6, further comprising: An indication of a reference tone at which the DC offset is to be located is received from a transmit receive point (TRP) that transmits the analog RF signal.

8. The method of claim 1, wherein: The analog RF signal includes one PRS resource spanning N component carriers, N is the folding factor of the first bandwidth, and The one PRS resource is part of one positioning frequency layer.

9. The method of claim 1, wherein: The analog RF signal includes N PRS resources, N is the folding factor of the first bandwidth, and Each of the N PRS resources is defined on a different positioning frequency layer.

10. The method of claim 1, further comprising: folding multiple blocks of contiguous tones or physical resource blocks (PRBs) carrying the analog RF signal, Wherein sampling the analog RF signal comprises sampling folded blocks of contiguous tones or PRBs carrying the analog RF signal.

11. The method of claim 1 , further comprising: folding a plurality of blocks of non-contiguous tones or PRBs carrying the analog RF signal, Wherein sampling the analog RF signal comprises sampling a folded plurality of non-contiguous frequency tones or PRBs carrying the analog RF signal.

12. The method of claim 1, further comprising: folding a plurality of interleaved subcarrier sets carrying the analog RF signal, Wherein sampling the analog RF signal comprises sampling a folded set of interleaved subcarriers carrying the analog RF signal.

13. The method of claim 1, wherein: The first bandwidth comprises an operating bandwidth of a TRP transmitting the analog RF signal, and The second bandwidth comprises an operating bandwidth of the UE.

14. The method of claim 13, wherein the bandpass filter operates at an operating bandwidth of the TRP.

15. A user equipment (UE), comprising: Memory; a bandpass filter of a radio frequency front end (RFFE) configured to receive an analog radio frequency (RF) signal having a first bandwidth associated with a first sampling rate, the analog RF signal including a positioning reference signal (PRS), wherein a mapping between frequency tones for transmitting the analog RF signal at the first bandwidth and frequency tones for receiving the analog RF signal at a second bandwidth lower than the first bandwidth is received; Analog-to-digital converter (ADC); and a baseband processor communicatively coupled to the ADC, wherein the ADC is configured to: sampling the analog RF signal at a second sampling rate to generate a digital RF signal representative of the analog RF signal, wherein the ADC operates at the second bandwidth, and wherein the second sampling rate is a reciprocal of the first sampling rate multiplied by a folding factor of the first bandwidth; as well as The digital RF signal is output to the baseband processor.

16. The UE according to claim 15, wherein: The first sampling rate is the Nyquist sampling rate of the first bandwidth, and The second sampling rate is a sub-Nyquist sampling rate of the first bandwidth.

17. The UE according to claim 15, wherein: The first sampling rate is N*R S ,and The second sampling rate is R S , where N is the folding factor of the first bandwidth and R S is the sampling rate.

18. The UE of claim 15, wherein the ADC is configured to sample the analog RF signal comprising: The ADC is configured to sample the analog RF signal based on the mapping.

19. The UE of claim 18, wherein the ADC being configured to sample the analog RF signal based on the mapping comprises: The ADC is configured to determine the folding factor for the first bandwidth based on the mapping.

20. The UE of claim 15, wherein the samples of the analog RF signal are centered about a direct current (DC) offset.

21. The UE of claim 20, wherein the ADC and the frequency converter are configured to: An indication of a reference tone at which the DC offset is to be located is received from a transmit receive point (TRP) that transmits the analog RF signal.

22. The UE of claim 15, wherein: The analog RF signal includes one PRS resource spanning N component carriers, N is the folding factor of the first bandwidth, and The one PRS resource is part of one positioning frequency layer.

23. The UE of claim 15, wherein: The analog RF signal includes N PRS resources, N is the folding factor of the first bandwidth, and Each of the N PRS resources is defined on a different positioning frequency layer.

24. The UE of claim 15, wherein the ADC and the frequency converter are configured to: folding multiple blocks of contiguous tones or physical resource blocks (PRBs) carrying the analog RF signal, The ADC is configured to sample the analog RF signal, comprising: The ADC is configured to sample folded blocks of contiguous tones or PRBs carrying the analog RF signal.

25. The UE of claim 15, wherein the ADC is further configured to: folding a plurality of blocks of non-contiguous tones or PRBs carrying the analog RF signal, The ADC is configured to sample the analog RF signal, comprising: The ADC is configured to sample folded blocks of non-contiguous tones or PRBs carrying the analog RF signal.

26. The UE of claim 15, wherein the ADC is further configured to: folding a plurality of interleaved subcarrier sets carrying the analog RF signal, The ADC is configured to sample the analog RF signal, comprising: The ADC is configured to sample a folded set of interleaved subcarriers carrying the analog RF signal.

27. The UE of claim 15, wherein: The first bandwidth comprises an operating bandwidth of a TRP transmitting the analog RF signal, and The second bandwidth comprises an operating bandwidth of the UE.

28. The UE of claim 27, wherein the bandpass filter operates with an operating bandwidth of the TRP.

29. A user equipment (UE), comprising: means for receiving, at a bandpass filter of a radio frequency front end (RFFE) of the UE, an analog radio frequency (RF) signal having a first bandwidth associated with a first sampling rate, the analog RF signal including a positioning reference signal (PRS); means for receiving a mapping between frequency tones for transmitting the analog RF signal at the first bandwidth and frequency tones for receiving the analog RF signal at a second bandwidth lower than the first bandwidth; means for sampling the analog RF signal at a second sampling rate to generate a digital RF signal representative of the analog RF signal, wherein the means for sampling operates at the second bandwidth, and wherein the second sampling rate is the inverse of the first sampling rate multiplied by a folding factor of the first bandwidth; as well as means for outputting the digital RF signal to a baseband processor of the UE.

30. The UE of claim 29, wherein: The first sampling rate is the Nyquist sampling rate of the first bandwidth, and The second sampling rate is a sub-Nyquist sampling rate of the first bandwidth.

31. The UE of claim 29, wherein: The first sampling rate is N*R S ,and The second sampling rate is R S , where N is the folding factor of the first bandwidth and R S is the sampling rate.

32. The UE of claim 29, wherein sampling the analog RF signal is based on the mapping.

33. The UE of claim 32, wherein sampling the analog RF signal comprises: The folding factor for the first bandwidth is determined based on the mapping.

34. The UE of claim 29, wherein samples of the analog RF signal are centered about a direct current (DC) offset.

35. The UE of claim 34, further comprising: Means for receiving, from a transmit receive point (TRP) transmitting the analog RF signal, an indication of a reference tone at which the DC offset is to be located.

36. The UE of claim 29, wherein: The analog RF signal includes one PRS resource spanning N component carriers, N is the folding factor of the first bandwidth, and The one PRS resource is part of one positioning frequency layer.

37. The UE of claim 29, wherein: The analog RF signal includes N PRS resources, N is the folding factor of the first bandwidth, and Each of the N PRS resources is defined on a different positioning frequency layer.

38. The UE of claim 29, further comprising: means for folding a plurality of blocks of contiguous tones or physical resource blocks (PRBs) carrying said analog RF signal, Wherein the means for sampling the analog RF signal comprises means for sampling a folded plurality of blocks of contiguous tones or PRBs carrying the analog RF signal.

39. The UE of claim 29, further comprising: means for folding a plurality of blocks of non-contiguous tones or PRBs carrying said analog RF signal, Wherein the means for sampling the analog RF signal comprises means for sampling a folded plurality of blocks of non-contiguous tones or PRBs carrying the analog RF signal.

40. The UE of claim 29, further comprising: means for folding a plurality of interleaved sets of subcarriers carrying said analog RF signal, Wherein the means for sampling the analog RF signal comprises means for sampling a folded set of interleaved subcarriers carrying the analog RF signal.

41. The UE of claim 29, wherein: The first bandwidth comprises an operating bandwidth of a TRP transmitting the analog RF signal, and The second bandwidth comprises an operating bandwidth of the UE.

42. The UE of claim 41 , wherein the bandpass filter operates with an operating bandwidth of the TRP.

43. A non-transitory computer-readable medium storing computer-executable instructions that, when executed by a user equipment (UE), cause the UE to: receiving, at a bandpass filter of a radio frequency front end (RFFE) of the UE, an analog radio frequency (RF) signal having a first bandwidth associated with a first sampling rate, the analog RF signal including a positioning reference signal (PRS); receiving a mapping between frequency tones for transmitting the analog RF signal at the first bandwidth and frequency tones for receiving the analog RF signal at a second bandwidth lower than the first bandwidth; sampling the analog RF signal at a second sampling rate by an analog-to-digital converter (ADC) to generate a digital RF signal representative of the analog RF signal, wherein the ADC operates at the second bandwidth, and wherein the second sampling rate is a reciprocal of the first sampling rate multiplied by a folding factor of the first bandwidth; as well as The digital RF signal is output to a baseband processor of the UE.

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