Systems and methods for enhanced multipath identification

Abstract

Some implementations herein relate to a device that receives and processes multiple spread spectrum signals corresponding to multiple linear frequency modulated (LFM) signals, including multipath LFM signals having directly and indirectly received signal components. Based on the transmission times and transmission locations of the multiple spread spectrum signals and the multiple LFM signals, the device can estimate the location of the device, the time the device was at a location, the arrival times of the directly and indirectly received signal components, and the time difference of arrival between the arrival times of the directly and indirectly received signal components. Based on the transmission locations, the device location, and the time difference of arrival, the device can estimate a range to a surface relative to the device location.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 63 / 449,138, filed March 1, 2023, which is incorporated by reference in its entirety. This disclosure includes subject matter related to that disclosed in PCT / US2022 / 014274, filed January 28, 2022, which is incorporated by reference in its entirety. [Background technology]

[0002] Multipath propagation occurs when a transmitted signal travels from a transmitter to a receiver and arrives via multiple paths due to reflection, diffraction, and / or scattering in the surrounding environment. These multiple paths may result in the receiver receiving several copies of the transmitted signal with slightly different, time-varying signal strengths. Summary of the Invention [Means for solving the problem]

[0003] Some implementations provided herein relate to a method related to enhanced multipath identification. The method can include receiving, by a device, a plurality of spread spectrum signals and a plurality of linear frequency modulated signals, where the plurality of linear frequency modulated signals include multipath linear frequency modulated signals having directly received signal components and indirectly received signal components, the indirectly received signal components reflected from a surface; receiving signal information indicating transmission times of the plurality of spread spectrum signals and the plurality of linear frequency modulated signals and transmission locations from which the plurality of spread spectrum signals and the plurality of linear frequency modulated signals were transmitted; estimating, by the device, a location of the device, a time the device was at a location, arrival times of the directly received signal components and the indirectly received signal components, and a time difference of arrival between the arrival times of the directly received signal components and the indirectly received signal components based on the transmission times and transmission locations; and estimating, by the device, a range to the surface relative to the device location based on the transmission locations, the device location, and the time difference of arrival.

[0004] Some implementations described herein relate to a transceiver device including one or more memories and one or more processors communicatively coupled to the one or more memories and configured to: receive a plurality of spread spectrum signals corresponding to a plurality of linear frequency modulated signals, the plurality of linear frequency modulated signals including multipath linear frequency modulated signals having directly received signal components and indirectly received signal components, the indirectly received signal components reflected from a surface; receive signal information, the signal information indicating transmission times of the plurality of spread spectrum signals and the plurality of linear frequency modulated signals and transmission locations from which the plurality of spread spectrum signals and the plurality of linear frequency modulated signals were transmitted; estimate a location of the transceiver device, a time the transceiver device was at a location, arrival times of the directly received signal components and the indirectly received signal components, and a time difference of arrival between the arrival times of the directly received signal components and the indirectly received signal components based on the transmission times and transmission locations; and estimate a range to the surface relative to the device location based on the transmission locations, the device location, and the time difference of arrival.

[0005] Some implementations described herein relate to a non-transitory computer-readable medium storing a set of instructions that, when executed by one or more processors of the device, cause the device to: receive a plurality of spread spectrum signals corresponding to a plurality of linear frequency modulated signals, the plurality of linear frequency modulated signals including multipath linear frequency modulated signals having directly received signal components and indirectly received signal components, the indirectly received signal components being reflected from a surface; receive signal information, the signal information indicating transmission times of the plurality of spread spectrum signals and the plurality of linear frequency modulated signals and transmission locations from which the plurality of spread spectrum signals and the plurality of linear frequency modulated signals were transmitted; estimate a location of a transceiver device, a time the transceiver device was at a location, arrival times of the directly received signal components and the indirectly received signal components, and a time difference of arrival between the arrival times of the directly received signal components and the indirectly received signal components based on the transmission times and transmission locations; and estimate a range to the surface relative to the device location based on the transmission locations, the device location, and the time difference of arrival. [Brief explanation of the drawings]

[0006] [Figure 1A] FIG. 1 is a diagram of an example related to enhanced multi-path identification, in accordance with some embodiments of the present disclosure. [Figure 1B] FIG. 1 is a diagram of an example related to enhanced multi-path identification, in accordance with some embodiments of the present disclosure. [Figure 1C] FIG. 1 is a diagram of an example related to enhanced multi-path identification, in accordance with some embodiments of the present disclosure. [Figure 1D] FIG. 1 is a diagram of an example related to enhanced multi-path identification, in accordance with some embodiments of the present disclosure. [Figure 1E] FIG. 1 is a diagram of an example related to enhanced multi-path identification, in accordance with some embodiments of the present disclosure. [Figure 1F] FIG. 1 is a diagram of an example related to enhanced multi-path identification, in accordance with some embodiments of the present disclosure. [Figure 1G] FIG. 1 is a diagram of an example related to enhanced multi-path identification, in accordance with some embodiments of the present disclosure. [Figure 2] FIG. 1 is a diagram of an exemplary environment in which the systems and / or methods described herein may be implemented, according to some embodiments of the present disclosure. [Figure 3] FIG. 2 is a diagram of example components of a device associated with enhanced multi-path identification, in accordance with some embodiments of the present disclosure. [Figure 4] 1 is a flowchart of an example process associated with enhanced multi-path identification, in accordance with some embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0007] The following detailed description of the exemplary embodiments refers to the accompanying drawings, in which the same reference numbers in different drawings may identify the same or similar elements.

[0008] Geolocation satellite systems, such as Global Navigation Satellite Systems (GNSS), transmit data indicative of location and timing information (e.g., satellite ephemeris information, clock correction information, almanac data, and / or atmospheric condition information, among other examples, via GNSS signals (e.g., direct sequence spread spectrum (DSSS) signals, etc.). A transceiver device (e.g., user equipment (UE), among other examples) receives and processes the GNSS signals (e.g., using one or more correlation and / or demodulation techniques, among other examples) to derive a location, velocity, and time (PVT) solution, which enables precise navigation and / or timing functionality.

[0009] In some cases, transmitted GNSS signals (e.g., transmitted by one or more GNSS satellites) are affected by multipath propagation, such as when the GNSS signals encounter a surface (e.g., of an object) and are reflected, diffracted, and / or scattered, causing the GNSS signals to take multiple paths before reaching a transceiver device. Multipath propagation can result in multipath interference (e.g., also referred to as multipath fading or multipath distortion). Multipath interference occurs when GNSS signals reach a receiver via multiple paths and interfere with each other destructively or constructively. As an example, destructive interference occurs when GNSS signals arriving via multiple paths have opposite phases that cancel each other out, resulting in attenuation or fading of the GNSS signal. This can result in reduced GNSS signal strength or data errors, among other examples. As another example, constructive interference occurs when GNSS signals arriving via different paths have similar phases that strengthen each other, resulting in strengthening of the GNSS signal. This can result in distortion of the GNSS signal and difficulties in decoding the transmitted data, among other examples. Multipath interference can therefore reduce the accuracy and reliability of the GNSS position and timing solutions produced by the transceiver device.

[0010] 1A-1G are diagrams of an example 100 related to enhanced multipath identification. As shown in FIG. 1A, the example 100 includes a transceiver device 102 (e.g., a user equipment (UE)), a first satellite 104 (e.g., a first GNSS satellite), a second satellite 106 (e.g., a second GNSS satellite), a third satellite 108 (e.g., a third GNSS satellite), and a fourth satellite 110 (e.g., a fourth GNSS satellite). The transceiver device 102, the first satellite 104, the second satellite 106, the third satellite 108, and the fourth satellite 110 can form an enhanced multipath identification architecture, as described in more detail elsewhere herein.

[0011] 1A, a first satellite 104 transmits a first set of signals 112, a second satellite 106 transmits a second set of signals 114, a third satellite 108 transmits a third set of signals 116, and a fourth satellite 110 transmits a fourth set of signals 118. The transceiver device 102 receives the first set of signals 112, the second set of signals 114, the third set of signals 116, and the fourth set of signals 118. The spread spectrum and / or LFM signals may be transmitted synchronously, asynchronously, and / or in any suitable manner.

[0012] In some implementations, each of the first set of signals 112, the second set of signals 114, the third set of signals 116, and the fourth set of signals 118 includes a spread-spectrum signal and a corresponding linear frequency modulated (LFM) signal. By way of example, each of the first set of signals 112, the second set of signals 114, the third set of signals 116, and the fourth set of signals 118 may include a DSSS signal and a corresponding linear chirp waveform (e.g., a sinusoidal waveform having a frequency that increases or decreases linearly over time, as described in more detail elsewhere herein).

[0013] In some implementations, the spread spectrum signal and / or LFM signal can be generated (e.g., by a waveform generator, among other examples) using one or more waveform generation techniques, using one or more modulation techniques, and / or complying with one or more access scheme requirements, among other examples. By way of example, the waveform generator can create a spread spectrum signal by generating a carrier signal at a particular frequency, such as that found in the L1 band, which operates at a frequency of approximately 1575.42 MHz, or the L5 band, which operates at a frequency of approximately 1176.45 MHz, among other examples. The waveform generator can modulate the carrier signal with an extension code (e.g., with a coarse / acquisition C / A code for the L1 band, which has a chip rate of 1.023 megachips per second (Mcps)), among other examples. The waveform generator can encode a navigation message (e.g., including PVT information) onto the carrier signal using one or more modulation techniques, such as binary phase shift keying (BPSK). The waveform generator may amplify the spread spectrum signal to reach a desired power level before providing it as an output (e.g., to the first satellite 104, the second satellite 106, the third satellite 108, and the fourth satellite 110).

[0014] As another example, a waveform generator can generate an LFM signal by generating precise, stable frequency signals (such as direct digital synthesis (DDS), voltage-controlled oscillator (VCO), and / or phase-locked loop (PLL) techniques, among other examples). These waveforms have frequencies that vary linearly over time with adjustable parameters such as start frequency, end frequency, sweep rate, and duration. FIG. 1B illustrates a first spectrograph 122 in which the LFM signal has a continuous positive slope frequency over a single time period, a second spectrograph 124 in which the LFM signal has a continuous negative slope frequency over a single time period, a third spectrograph 126 in which the LFM signal has multiple positive frequency slopes (e.g., discontinuous positive frequency slopes) over multiple time periods, and a fourth spectrograph 128 in which the LFM signal has a continuous frequency slope including a positive frequency slope in a first time period, a zero frequency slope in a second time period, a negative frequency slope (e.g., no change in frequency slope) in a third time period, and a zero frequency slope in a fourth time period.

[0015] 1B in spectrographs 122, 124, 126, and 128, the LFM signal may have any suitable frequency slope. The waveform generator may amplify the power level of the LFM signal before providing it as an output (e.g., to the first satellite 104, the second satellite 106, the third satellite 108, and the fourth satellite 110). The spread spectrum and / or LFM signals (e.g., generated by a waveform generator and transmitted by the first satellite 104, the second satellite 106, the third satellite 108, and / or the fourth satellite 110) may include any suitable permutation of signal types based on any suitable modulation technique (e.g., DSSS and / or chirp spread spectrum (CSS)), access method (e.g., code division multiple access (CDMA) and / or time division multiple access (TDMA)), and / or protocol (e.g., system-specific protocol), and / or any suitable combination of modulation techniques, access methods, and / or protocols, among other examples.

[0016] In some implementations, the first set of signals 112, the second set of signals 114, the third set of signals 116, and / or the fourth set of signals 118 may include multipath signals. As an example, as shown in FIG. 1A , the third set of signals 116 includes multipath signals received by the transceiver device 102 via a direct line-of-sight path 116a and a multipath signal received via an indirect non-line-of-sight path 116b. In other words, the spread spectrum signal and the corresponding LFM signal transmitted by the third satellite 108 are reflected from the surface of the object 120 before being received by the transceiver device 102. Thus, the third signal set 116 includes directly received (e.g., related to spread spectrum and LFM signals traveling along a direct line-of-sight path 116a) signal components of the spread spectrum and LFM signals, as well as indirectly received (e.g., related to spread spectrum and LFM signals traveling along an indirect, non-line-of-sight path 116b) signal components of the spread spectrum and LFM signals.

[0017] In some implementations, as described in more detail elsewhere herein, the transceiver device 102 can receive signal information related to the transmission times of the first set of signals 112, the second set of signals 114, the third set of signals 116, and the fourth set of signals 118, and the transmission locations from which the first set of signals 112, the second set of signals 114, the third set of signals 116, and the fourth set of signals 118 were transmitted. As described in more detail elsewhere herein, the transceiver device 102 can process the signal information to derive a PVT solution related to the transceiver device 102, the first satellite 104, the second satellite 106, the third satellite 108, the fourth satellite 110, and / or the object 120.

[0018] By way of example, and as described in more detail elsewhere herein, the UE 102 may process the first set of signals 112, the second set of signals 114, the third set of signals 116, and the fourth set of signals 118 to determine, among other examples, the location of the UE 102, the time the UE 102 was at that location, the first transmission time of the first set of signals 112, the first location of the first satellite 104 at the first transmission time, the second transmission time of the second set of signals 114, the second location of the second satellite 106 at the second transmission time, the third transmission time of the third set of signals 116, the fourth location of the second satellite 106 at the second transmission time, the fourth transmission time of the third set of signals 116, the fifth transmission time of the third set of signals 118, the fifth transmission time of the third set of signals 118, the sixth transmission time of the second set of signals 118, the sixth transmission time of the third set of signals 118, the seventh transmission time of the second set of signals 118, the eighth transmission time of the second set of signals 118, the eighth transmission time of the third ... The transmission time, the third location of the third satellite 108 at the third transmission time, the fourth transmission time of the fourth set of signals 118, the fourth location of the fourth satellite 110 at the fourth transmission time, the first range of the object 120 relative to the transceiver device 102 (e.g., the range to the surface of the object reflecting the third set of signals 116), the fifth time that the object 120 was in that range, the orientation of the object 120 relative to the location of the transceiver device 102, and / or the velocity of the object 120 relative to the transceiver device 102 can be derived.

[0019] In some implementations, the transceiver device 102 receives signal information indicating the transmission times of the spread spectrum signals and the LFM signals and the transmission locations from which the spread spectrum signals and the LFM signals were transmitted via navigation messages included in the spread spectrum signals. For example, the spread spectrum signals of the first signal set 112 may include a first navigation message indicating first transmission times of the spread spectrum signals and the LFM signals (e.g., included in the first signal set 112) and a first transmission location from which the spread spectrum signals and the LFM signals were transmitted (e.g., by the first satellite 104).

[0020] As another example, the spread spectrum signals of the second signal set 114 may include a second navigation message indicating a second transmission time of the spread spectrum signals and LFM signals (e.g., included in the second signal set 114) and a second transmission location from which the spread spectrum signals and LFM signals were transmitted (e.g., by a second satellite 106).

[0021] As another example, the spread spectrum signals of the third signal set 116 may include a third navigation message indicating a third transmission time of the spread spectrum signals and the LFM signals (e.g., included in the third signal set 116) and a third transmission location from which the spread spectrum signals and the LFM signals were transmitted (e.g., by the third satellite 108). As yet another example, the spread spectrum signals of the fourth signal set 118 may include a fourth navigation message indicating a fourth transmission time of the spread spectrum signals and the LFM signals (e.g., included in the fourth signal set 118) and a fourth transmission location from which the spread spectrum signals and the LFM signals were transmitted (e.g., by the fourth satellite 110).

[0022] Although the transceiver device 102 is described as receiving signal information indicating the transmission times of the spread spectrum signals and the LFM signals and the transmission locations from which the spread spectrum signals and the LFM signals were transmitted via navigation messages included in the spread spectrum signals (e.g., transmitted by the first satellite 104, the second satellite 106, the third satellite 108, and the fourth satellite 110), the transceiver device 102 may receive the signal information in any suitable manner. For example, the transceiver device 102 may receive the signal information via a wired or wireless network (or connection). By way of example, the transceiver device 102 may receive the signal information via an Internet connection, a memory device (e.g., a hard drive and / or a digital database, among other examples), and / or a peer-to-peer network, among other examples. Furthermore, the transceiver device 102 may receive the signal information before the spread spectrum signals and / or the LFM signals are transmitted, after the spread spectrum signals and / or the LFM signals are transmitted, and / or at any other suitable time.

[0023] Although the spread spectrum signals and corresponding LFM signals (e.g., included in each of the first signal set 112, the second signal set 114, the third signal set 116, and the fourth signal set 118) are described as being transmitted at a single transmission time, the spread spectrum signals and corresponding LFM signals may be transmitted at separate times (e.g., the navigation message may indicate a first transmission time of the spread spectrum signals and a second transmission time of the corresponding LFM signals that is earlier or later than the first transmission time). Similarly, although the spread spectrum signals and corresponding LFM signals (e.g., included in each of first signal set 112, second signal set 114, third signal set 116, and fourth signal set 118) are described as being transmitted from a single location, the spread signals and corresponding LFM signals may be transmitted from different locations (e.g., the navigation message may indicate a first transmission location from which the spread spectrum signals were transmitted and a second transmission location from which the corresponding LFM signals were transmitted or are to be transmitted).

[0024] Additionally or alternatively, the navigation message may indicate the transmission time of one or more different signals (e.g., spread spectrum signals and / or LFM signals included in the set of different signals) and / or the transmission location from which the one or more different signals have been or should be transmitted. Although the transceiver device 102 is described as receiving the signal information indicating the transmission times of the spread spectrum signals and the LFM signals and the transmission locations from which the spread spectrum signals and the LFM signals have been or should be transmitted via the spread spectrum signal navigation message, the transceiver device 102 may receive the signal information in any suitable manner. By way of example, the transceiver device 102 may receive the signal information from a server device (e.g., via an over-the-air or wireless network connection), among other examples. Based on the signal information, the transceiver device 102 may determine the transmission time and transmission location from which the LFM signal has been or should be transmitted (e.g., at the transmission time).

[0025] In some implementations, the spread-spectrum and LFM signals (e.g., included in each of the first set of signals 112, the second set of signals 114, the third set of signals 116, and the fourth set of signals 118) can be transmitted as a hybrid signal (e.g., a hybrid signal including a spread-spectrum signal and an LFM signal, as described in more detail elsewhere herein). As shown in FIG. 1C, the first hybrid signal 130 includes a linear chirp waveform 132 and a DSSS signal 134 that are time-aligned to be contiguous. As shown in FIG. 1D, the second hybrid signal 130a includes a linear chirp waveform 132 and a DSSS signal 134 that are time-aligned to be simultaneous.

[0026] 1E, the first hybrid signal set 136 includes a first linear chirp waveform 140 corresponding to a first DSSS signal 142 transmitted at a time later than the time at which the first DSSS signal 142 is transmitted. As further shown in FIG. 1E, the second hybrid signal set 138 includes a second linear chirp waveform 144 corresponding to a second DSSS signal 146 transmitted at a time later than the time at which the second DSSS signal 146 is transmitted.

[0027] As shown in Figure 1F, the first set of hybrid signals 148 includes a first linear chirp waveform 150 corresponding to the first DSSS signal 152 that is transmitted at a time earlier than the time at which the first DSSS signal 152 is transmitted. As further shown in Figure 1F, the second set of hybrid signals 148a includes a second linear chirp waveform 154 corresponding to the second DSSS signal 156 that is transmitted at a time earlier than the time at which the second DSSS signal 156 is transmitted. Although particular hybrid signals and sets of hybrid signals are shown and described with respect to Figures 1C-1F, the spread spectrum signals (e.g., DSSS signals) and / or LFM signals may be transmitted in any suitable manner. Further, with respect to Figures 1C-1E, the DSSS signals and LFM signals are described as hybrid signals and sets of hybrid signals, but the DSSS signals may be associated with any suitable linear chirp waveforms (e.g., the navigation message included in the DSSS signal may indicate transmission times related to multiple linear chirp waveforms and transmission locations where the multiple linear chirp waveforms have been or should be transmitted).

[0028] In some implementations, the first set of signals 112, the second set of signals 114, the third set of signals 116, and / or the fourth set of signals 118 may include multipath signals. As an example, as shown in FIG. 1A , the third set of signals 116 includes multipath signals received by the transceiver device 102 via a direct line-of-sight path 116a and a multipath signal received via an indirect non-line-of-sight path 116b. In other words, the spread spectrum signal and the corresponding LFM signal transmitted by the third satellite 108 are reflected from the surface of the object 120 before being received by the transceiver device 102. Thus, the third signal set 116 includes directly received (e.g., related to spread spectrum and LFM signals traveling along a direct line-of-sight path 116a) signal components of the spread spectrum and LFM signals, as well as indirectly received (e.g., related to spread spectrum and LFM signals traveling along an indirect, non-line-of-sight path 116b) signal components of the spread spectrum and LFM signals.

[0029] In some implementations, the transceiver device 102 may process the first set of signals 112, the second set of signals 114, the third set of signals 116, and the fourth set of signals 118 to derive location, velocity, and time (PVT) information related to the transceiver device 102, the first satellite 104, the second satellite 106, the third satellite 108, the fourth satellite 110, and / or the object 120. By way of example, and as described in more detail elsewhere herein, the transceiver device 102 may process the first set of signals 112, the second set of signals 114, the third set of signals 116, and the fourth set of signals 118 to derive, among other examples, the location of the transceiver device 102, the time that the transceiver device 102 was at that location, the first transmission time of the first set of signals 112, the first location of the first satellite 104 at the first transmission time, the second transmission time of the second set of signals 114, and the like. , a second location of the second satellite 106 at the second transmission time, a third transmission time of the third set of signals 116, a third location of the third satellite 108 at the third transmission time, a fourth transmission time of the fourth set of signals 118, a fourth location of the fourth satellite 110 at the fourth transmission time, a first range to the object 120 relative to the transceiver device 102 (e.g., a range to the surface of the object that reflects the third set of signals 116), and a fifth time that the object 120 is in that range can be derived.

[0030] In this manner, the transceiver device 102 can implement enhanced multipath identification techniques to distinguish multipath signals from directly received signals (e.g., because the transceiver device 102 receives information that enables the transceiver device to determine the time-of-arrival difference between the arrival times of the directly received signal component of the LFM signal and the indirectly received signal component of the LFM signal). As a result, the transceiver device 102 can process the LFM signal in addition to the spread-spectrum signal to derive a more accurate PVT solution (e.g., a more accurate determination of the location of the transceiver device 102 and the time the transceiver device 102 was at that location) compared to typical multipath processing techniques. Additionally or alternatively, as described in more detail elsewhere herein, the transceiver device 102 may perform enhanced multipath discrimination (e.g., based on accurately and efficiently distinguishing between directly received signal components of the LFM signal and indirectly received components of the LFM signal), thereby enabling the transceiver device 102 to accurately and efficiently locate and / or track objects in close proximity to the transceiver device 102 (e.g., buildings in close proximity to the transceiver device 102).

[0031] 1G , the enhanced multipath discrimination architecture (e.g., formed by the transceiver device 102, the first satellite 104, the second satellite 106, the third satellite 108, and the fourth satellite 110) may be used by a vehicle 158 (e.g., an autonomous or non-autonomous vehicle) orbiting in an urban environment 160. The urban environment 160 includes a first building 162, a second building 164, a third building 166, and a fourth building 168, each of which is disposed on a ground surface 170.

[0032] 1G, first satellite 104 transmits first set of signals 172 and second set of signals 174, second satellite 106 transmits third set of signals 176 and fourth set of signals 178, third satellite 108 transmits fifth set of signals 180, and fourth satellite 110 transmits sixth set of signals 182 and seventh set of signals 184. First set of signals 172, second set of signals 174, third set of signals 176, fourth set of signals 178, fifth set of signals 180, sixth set of signals 182, and seventh set of signals 184 may include spread spectrum signals and LFM signals, as described in more detail elsewhere herein.

[0033] 1G, a first set of signals 172 is blocked by the second building 164 and therefore is not received by the transceiver device 102. A second set of signals 174 includes multipath signals received by the transceiver device 102 via a direct line-of-sight path 174a and multipath signals received via an indirect non-line-of-sight path 174b (e.g., reflected from a surface of the third building 166). A third set of signals 176 is directly received by the transceiver device 102. A fourth set of signals 178 includes multipath signals received by the transceiver device 102 via a direct line-of-sight path 178a and multipath signals received via an indirect non-line-of-sight path 178b (e.g., reflected from a surface of the third building 166). A fifth set of signals 180 is directly received by the transceiver device 102. A sixth set of signals 182 includes multipath signals received by the transceiver device 102 via a direct line-of-sight path 182a and multipath signals received via an indirect non-line-of-sight path 182b (e.g., reflected from a surface of the second building 164). A seventh set of signals 184 is blocked by the third building 166 and, therefore, is not received by the transceiver device 102.

[0034] As described in more detail elsewhere herein, the transceiver device 102 can receive signal information related to the received signal. The transceiver device 102 can process the received signal based on the signal information and estimate the location of the transceiver device (e.g., corresponding to the vehicle position of the vehicle 158), the time the transceiver device 102 was at that location (e.g., corresponding to the time the vehicle was at the vehicle position), the arrival times of the directly and indirectly received signal components, and the time difference in arrival between the arrival times of the directly and indirectly received signal components (e.g., based on the transmission times and transmission locations of the received signals). The transceiver device 102 can estimate (e.g., based on the transmission locations) the device location, the time difference in arrival, and the range to surfaces (e.g., surfaces of the second building 164 and the third building 166 that reflect the indirectly received signal components) relative to the location of the transceiver device 102 (e.g., relative to the vehicle position of the vehicle 158).

[0035] In this manner, the transceiver device 102 may process the LFM signal in addition to the spread-spectrum signal to derive a more accurate PVT solution (e.g., a more accurate determination of the location of the transceiver device 102 and the time the transceiver device 102 was at that location) compared to typical multipath processing techniques. Additionally or alternatively, as described in more detail elsewhere herein, the transceiver device 102 may perform enhanced multipath discrimination (e.g., based on accurately and efficiently discriminating between directly received signal components of the LFM signal and indirectly received components of the LFM signal), thereby enabling the transceiver device 102 to accurately and efficiently locate and / or track objects in close proximity to the transceiver device 102 (e.g., buildings in close proximity to the transceiver device 102).

[0036] 2 is a diagram of an example environment 200 in which the systems and / or methods described herein may be implemented. As shown in FIG. 2, environment 200 may include transceiver device 102, a set of GNSS satellites 202, and a network 204. The devices of environment 200 may be interconnected via wired connections, wireless connections, or a combination of wired and wireless connections.

[0037] The transceiver device 102 may include one or more devices capable of receiving, generating, storing, processing, providing, and / or routing information related to enhanced multipath identification, as described elsewhere herein. The transceiver device 102 may include a communications device and / or a computer. For example, the transceiver device 102 may include a wireless communications device, a mobile phone, user equipment, a laptop computer, a tablet computer, a desktop computer, a wearable communications device (e.g., a smart watch, a pair of smart glasses, a head-mounted display, or a virtual reality headset, among other examples), or a similar type of device.

[0038] The GNSS satellite set 202 may include a set or constellation of satellites in orbit (e.g., around the Earth) that provide position, navigation, and timing information via spread spectrum signals (e.g., DSSS signals, among other examples) and LFM signals (e.g., linear chirp waveforms, among other examples). The spread spectrum and LFM signals may be received and processed by terrestrial receivers (e.g., the transceiver device 102 and / or user equipment (UE), among other examples) to enable accurate location determination and precise timekeeping, as well as enhanced multipath discrimination.

[0039] Network 204 may include one or more wired and / or wireless networks. For example, network 204 may include a wireless wide area network (e.g., a cellular network or a public land mobile network), a local area network (e.g., a wired local area network or a wireless local area network (WLAN) such as a WiFi network), a personal area network (e.g., a Bluetooth network), a near field communication network, a telephone network, a private network, the Internet, and / or a combination of these or other types of networks. Network 204 enables communication between devices in environment 200.

[0040] The number and arrangement of devices and networks shown in Figure 2 are provided as an example. In practice, there may be more, fewer, different, or differently arranged devices and / or networks than those shown in Figure 2. Furthermore, two or more devices shown in Figure 2 may be implemented within a single device, or a single device shown in Figure 2 may be implemented as multiple distributed devices. Additionally or alternatively, a set of devices (e.g., one or more devices) of environment 200 may perform one or more functions that are described as being performed by another set of devices of environment 200.

[0041] 3 is a diagram of example components of a device 300 associated with enhanced multipath identification. The device 300 may correspond to the transceiver device 102, the first satellite 104, the second satellite 106, the third satellite 108, the fourth satellite 110, and / or the set of GNSS satellites 202. In some implementations, the transceiver device 102, the first satellite 104, the second satellite 106, the third satellite 108, the fourth satellite 110, and / or the set of GNSS satellites 202 may include one or more devices 300 and / or one or more components of the device 300. As shown in FIG. 3 , the device 300 may include a bus 310, a processor 320, a memory 330, an input component 340, an output component 350, and / or a communication component 360.

[0042] The bus 310 may include one or more components that enable wired and / or wireless communication between components of the device 300. The bus 310 may couple two or more components of FIG. 3 together via operational, communicative, electronic, and / or electrical couplings, etc. For example, the bus 310 may include electronic connections (e.g., wires, traces, and / or leads) and / or a wireless bus. The processor 320 may include a central processing unit, a graphics processing unit, a microprocessor, a controller, a microcontroller, a digital signal processor, a field programmable gate array, an application-specific integrated circuit, and / or another type of processing component. The processor 320 may be implemented in hardware, firmware, and / or software. In some implementations, the processor 320 may include one or more processors that can be programmed to perform one or more operations or processes described elsewhere herein.

[0043] The memory 330 may include volatile and / or nonvolatile memory. For example, the memory 330 may include random access memory (RAM), read-only memory (ROM), a hard disk drive, and / or another type of memory (e.g., flash memory, magnetic memory, and / or optical memory). The memory 330 may include internal memory (e.g., RAM, ROM, or a hard disk drive) and / or removable memory (e.g., removable via a Universal Serial Bus connection). The memory 330 may be a non-transitory computer-readable medium. The memory 330 may store information, one or more instructions, and / or software (e.g., one or more software applications) related to the operation of the device 300. In some implementations, the memory 330 may include one or more memories coupled (e.g., communicatively coupled) to one or more processors (e.g., processor 320), such as via bus 310. The communicative coupling between the processor 320 and the memory 330 may enable the processor 320 to read and / or process information stored in the memory 330 and / or store information in the memory 330.

[0044] The input component 340 may enable the device 300 to receive input, such as user input and / or sensed input. For example, the input component 340 may include a touchscreen, a keyboard, a keypad, a mouse, buttons, a microphone, switches, sensors, global positioning system sensors, accelerometers, gyroscopes, and / or actuators. The output component 350 may enable the device 300 to provide output, such as via a display, a speaker, and / or a light-emitting diode. The communication component 360 may enable the device 300 to communicate with other devices via wired and / or wireless connections. For example, the communication component 360 may include a receiver, a transmitter, a transceiver, a modem, a network interface card, and / or an antenna.

[0045] The device 300 can perform one or more operations or processes described herein. For example, a non-transitory computer-readable medium (e.g., memory 330) can store a set of instructions (e.g., one or more instructions or code) for execution by the processor 320. The processor 320 can execute the set of instructions to perform one or more operations or processes described herein. In some implementations, execution of a set of instructions by one or more processors 320 causes one or more processors 320 and / or the device 300 to perform one or more operations or processes described herein. In some implementations, hardwired circuitry can be used in place of or in combination with instructions to perform one or more operations or processes described herein. Additionally or alternatively, the processor 320 can be configured to perform one or more operations or processes described herein. Thus, the implementations described herein are not limited to any specific combination of hardware circuitry and software.

[0046] The number and arrangement of components shown in Figure 3 are provided as an example. Device 300 may include additional, fewer, different, or differently arranged components than those shown in Figure 3. Additionally or alternatively, a set of components (e.g., one or more components) of device 300 may perform one or more functions that are described as being performed by another set of components of device 300.

[0047] 4 is a flowchart of an example process 400 related to enhanced multipath identification. In some implementations, one or more process blocks of FIG. 4 may be performed by the transceiver device 102. In some implementations, one or more process blocks of FIG. 4 may be performed by another device (e.g., the first satellite 104, the second satellite 106, the third satellite 108, the fourth satellite 110, and / or the set of GNSS satellites 202) or a group of devices separate from or including the transceiver device 102. Additionally or alternatively, one or more process blocks of FIG. 4 may be performed by one or more components of the device 300, such as the processor 320, the memory 330, the input component 340, the output component 340, and / or the communication component 360.

[0048] 4, process 400 includes receiving, by a device, a plurality of spread spectrum signals and a plurality of linear frequency modulated signals (block 410), as described above. The plurality of linear frequency modulated signals may include multipath linear frequency modulated signals having directly received signal components and indirectly received signal components. The indirectly received signal components may be reflected from surfaces.

[0049] As further shown in FIG. 4 , process 400 includes receiving, by the device (block 420), signal information indicating transmission times of the plurality of spread spectrum signals and the plurality of linear frequency modulated signals and transmission locations from which the plurality of spread spectrum signals and the plurality of linear frequency modulated signals were transmitted, as described above.

[0050] As further shown in FIG. 4, process 400 includes estimating, by the device, based on the transmission time and transmission location, as described above, the location of the device, the time the device was at that location, the arrival times of the directly and indirectly received signal components, and the arrival time difference between the arrival times of the directly and indirectly received signal components (block 430).

[0051] As further shown in FIG. 4, process 400 includes estimating, by the device, a range to the surface relative to the device's location based on the transmission location, the device's location, and the time difference of arrival, as described above (block 440).

[0052] 4 illustrates example blocks of process 400, in some implementations, process 400 may include additional, fewer, different, or differently arranged blocks than those depicted in FIGURE 4. Additionally or alternatively, two or more of the blocks of process 400 may be performed in parallel.

[0053] As used herein, the term "component" is intended to be broadly interpreted as hardware, firmware, and / or software. It will be apparent that the systems and / or methods described herein can be implemented in different forms of hardware, firmware, and / or software. The actual dedicated control hardware or software code used to implement these systems and / or methods does not limit the implementation. Thus, the operation and behavior of the present systems and / or methods will be described herein without reference to specific software code, with the understanding that software and hardware can be used to implement the present systems and / or methods based on the description herein.

[0054] As used herein, meeting a threshold may refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, etc., depending on the context.

[0055] To the extent that the above-described implementations collect, store, or use personal information of individuals, it should be understood that such information should be used in accordance with all applicable laws regarding the protection of personal information. Additionally, the collection, storage, and use of such information may seek the individual's consent to such activities, for example, through well-known "opt-in" or "opt-out" processes that may be appropriate for the circumstances and type of information. The storage and use of personal information may be in an appropriately secure manner that reflects the type of information, for example, through various encryption and anonymization techniques, particularly for sensitive information.

[0056] Although particular combinations of features are recited in the claims and / or disclosed herein, these combinations are not intended to limit the disclosure of various implementations. Indeed, many of these features can be combined in ways not specifically recited in the claims and / or disclosed herein. Although each dependent claim listed below may depend directly on only one claim, the disclosure of various implementations includes each dependent claim in combination with every single claim in the set of claims. As used herein, phrases referring to "at least one of" a list of items refer to any combination of those items, including single members. By way of example, "at least one of a, b, or c" is intended to cover a, b, c, ab, ac, bc, and abc, as well as any combination with various of the same items.

[0057] When a "processor" or "one or more processors" (or another device or component, such as a "controller" or "one or more controllers") is described or claimed (in a single claim or across multiple claims) as performing or configured to perform multiple operations, this term is intended to broadly cover a variety of processor architectures and environments. For example, unless expressly asserted otherwise (e.g., through the use of a "first processor" and a "second processor" or other language identifying processors in a claim), this term is intended to cover a single processor that performs or is configured to perform all of the operations, a group of processors that collectively perform or are configured to perform all of the operations, a first processor that performs or is configured to perform a first operation and a second processor that performs or is configured to perform a second operation, or any combination of processors that perform or are configured to perform operations. For example, if a claim has the format "one or more processors configured to perform X, perform Y, and perform Z," the claim should be interpreted to mean "one or more processors configured to perform X, one or more (possibly different) processors configured to perform Y, and one or more (again, possibly different) processors configured to perform Z."

[0058] Unless expressly stated to be so, no element, act, or instruction used herein should be construed as critical or required. Additionally, as used herein, the articles "a" and "an" are intended to include one or more items and may be used interchangeably with "one or more." Additionally, as used herein, the article "the" is intended to include one or more items referenced in connection with the article "the" and may be used interchangeably with "said one or more." Additionally, as used herein, the term "set" is intended to include one or more items (e.g., related items, unrelated items, or a combination of related and unrelated items) and may be used interchangeably with "one or more." Where only one item is intended, the term "only one" or similar language is used. Additionally, as used herein, terms such as "has," "have," "having," and the like are intended to be open-ended terms. Additionally, the phrase "based on" is intended to mean "based at least in part on," unless expressly stated otherwise. Also, as used herein, the term "or" is intended to be inclusive when used in a sequence unless expressly stated otherwise (e.g., when used in combination with "either" or "only one of"), and may be used interchangeably with "and / or."

[0059] In the foregoing specification, various exemplary embodiments have been described with reference to the accompanying drawings. However, it will be apparent that various modifications and changes may be made thereto, and that additional embodiments may be implemented, without departing from the broader scope of the invention as set forth in the following claims. Accordingly, the specification and drawings should be regarded in an illustrative rather than a restrictive sense. [Explanation of symbols]

[0060] 100 examples 102 Transceiver Device 104 First Satellite 106 Second Satellite 108 Third Satellite 110 The Fourth Satellite 112 First set of signals 114 Second set of signals 116 Third set of traffic lights 116a Direct line of sight 116b Indirect non-line-of-sight path 118 Fourth set of traffic lights 120 Object 122 First Spectrograph 124 Second Spectrograph 126 The Third Spectrograph 128 The Fourth Spectrograph 130 First Hybrid Signal 130a Second Hybrid Signal 132 Linear Chirp Waveform 134 DSSS signal 136 First set of hybrid signals 138 Second set of hybrid signals 140 First Linear Chirp Waveform 142 First DSSS signal 144 Second Linear Chirp Waveform 146 Second DSSS Signal 148 First set of hybrid signals 148a Second set of hybrid signals 150 First Linear Chirp Waveform 152 First DSSS signal 154 Second Linear Chirp Waveform 156 Second DSSS Signal 158 vehicles 160 Urban environment 162 First Building 164 Second Building 166 Third Building 168 Fourth Building 170 Ground 172 First set of signals 174 Second set of signals 174a Direct line of sight 174b Indirect non-line-of-sight path 176 Third set of traffic lights 178 Fourth Set of Traffic Lights 178a Direct line of sight 178b Indirect non-line-of-sight path 180 5th traffic light set 182 Sixth Set of Traffic Lights 182a Direct line of sight 182b Indirect non-line-of-sight path 184 Seventh Signal Set 200 Environment 202 GNSS satellite pairs 204 Network 300 devices 310 Bus 320 processor 330 memory 340 Input Components 350 Output Components 360 Communication Components 400 processes

Claims

1. receiving, by a device, a plurality of spread spectrum signals and a plurality of linear frequency modulated signals; the plurality of linear frequency modulated signals includes a multipath linear frequency modulated signal having directly received and indirectly received signal components; the indirectly received signal component is reflected from a surface; Steps and receiving signaling information, the signaling information comprising: transmission times of the plurality of spread spectrum signals and the plurality of linear frequency modulated signals; and a transmitting location where the plurality of spread spectrum signals and the plurality of linear frequency modulated signals are transmitted; , indicating a step; by the device based on the transmission time and the transmission location; the location of the device; the amount of time the device was at the location; arrival times of the directly received signal components and the indirectly received signal components; and The arrival time difference between the arrival times of the directly received signal component and the indirectly received signal component. and estimating estimating, by the device, a range to the surface relative to the location of the device based on the transmission location, the location of the device, and the time difference of arrival; A method comprising:

2. the plurality of spread spectrum signals and the plurality of linear frequency modulated signals are corresponding signal pairs; The method of claim 1 , wherein each of the corresponding pairs of signals are synchronized in time with one another.

3. the plurality of spread spectrum signals and the plurality of linear frequency modulated signals Sync, or Asynchronous The method of claim 1 , wherein the signal is received by at least one of:

4. 2. The method of claim 1, wherein a frequency of at least one of the plurality of linear frequency modulated signals includes a first frequency component and a second frequency component different from the first frequency component.

5. The method of claim 1 , wherein the signal information is included in a navigation message of the plurality of spread spectrum signals.

6. The method of claim 1 , wherein the spread spectrum signal is a direct sequence spread spectrum signal.

7. adjusting, by the device, the trajectory of the device based on the range. The method of claim 1 further comprising:

8. one or more memories; one or more processors communicatively coupled to the one or more memories, receiving a plurality of spread spectrum signals corresponding to a plurality of linear frequency modulated signals; the plurality of linear frequency modulated signals includes a multipath linear frequency modulated signal having directly received and indirectly received signal components; the indirectly received signal component is reflected from a surface; Receiving and receiving signaling information, the signaling information comprising: transmission times of the plurality of spread spectrum signals and the plurality of linear frequency modulated signals; and a transmitting location where the plurality of spread spectrum signals and the plurality of linear frequency modulated signals are transmitted; and Based on the transmission time and the transmission location, Location of the transceiver device, the amount of time the transceiver device was at the location; arrival times of the directly received signal components and the indirectly received signal components; and The arrival time difference between the arrival times of the directly received signal component and the indirectly received signal component. and estimating estimating a range to the surface relative to the location of the device based on the transmission location, the location of the device, and the time difference of arrival; one or more processors configured to: A transceiver device comprising:

9. the plurality of spread spectrum signals and the plurality of linear frequency modulated signals are corresponding signal pairs; 9. The transceiver device of claim 8, wherein each corresponding one of the corresponding signal pairs are synchronized in time with one another.

10. the plurality of spread spectrum signals and the plurality of linear frequency modulated signals are transmitted by the transceiver device: simultaneously, or sequentially 9. The transceiver device of claim 8, wherein the signal is received by at least one of:

11. 9. The transceiver device of claim 8, wherein a frequency of at least one of the plurality of linear frequency modulated signals includes a first frequency component and a second frequency component different from the first frequency component.

12. 9. The transceiver device of claim 8, wherein the signal information is included in a navigation message of the plurality of spread spectrum signals.

13. 9. The transceiver device of claim 8, wherein the spread spectrum signal is a direct sequence spread spectrum signal.

14. the one or more processors: Adjusting the trajectory of the device based on the range.

9. The transceiver device of claim 8, configured to:

15. A non-transitory computer readable medium storing a set of instructions, the set of instructions comprising: When executed by one or more processors of a device, the device receiving a plurality of spread spectrum signals corresponding to a plurality of linear frequency modulated signals; the plurality of linear frequency modulated signals includes a multipath linear frequency modulated signal having directly received and indirectly received signal components; the indirectly received signal component is reflected from a surface; Receiving and receiving signaling information, the signaling information comprising: transmission times of the plurality of spread spectrum signals and the plurality of linear frequency modulated signals; and a transmitting location where the plurality of spread spectrum signals and the plurality of linear frequency modulated signals are transmitted; and Based on the transmission time and the transmission location, the location of the device; the amount of time the device was at the location; arrival times of the directly received signal components and the indirectly received signal components; and The arrival time difference between the arrival times of the directly received signal component and the indirectly received signal component. and estimating estimating a range to the surface relative to the location of the device based on the transmission location, the location of the device, and the time difference of arrival; 10. A non-transitory computer-readable medium comprising one or more instructions for causing a

16. the plurality of spread spectrum signals and the plurality of linear frequency modulated signals are corresponding signal pairs; 16. The non-transitory computer-readable medium of claim 15, wherein each corresponding one of the corresponding signal pairs are synchronized in time with one another.

17. the plurality of spread spectrum signals and the plurality of linear frequency modulated signals simultaneously, or sequentially 16. The non-transitory computer-readable medium of claim 15, received by at least one of:

18. 16. The non-transitory computer-readable medium of claim 15, wherein a frequency of at least one of the plurality of linear frequency modulated signals includes a first frequency component and a second frequency component different from the first frequency component.

19. 16. The non-transitory computer-readable medium of claim 15, wherein the signal information is included in a navigation message of the plurality of spread spectrum signals.

20. 16. The non-transitory computer-readable medium of claim 15, wherein the spread spectrum signal is a direct sequence spread spectrum signal.

Images