TDOA positioning method and system based on channel estimation and channel equalization, and electronic device

Abstract

The present invention provides a TDOA positioning method. K receiving base stations are employed to position an unmanned aerial vehicle. The method comprises: each receiving base station receiving a signal within its measurement range and, if a pilot signal is received, generates first target data; obtaining pilot information of the pilot signal on the basis of the first target data; obtaining an estimated channel time-domain response on the basis of the pilot information; on the basis of the estimated channel time-domain response, obtaining a tap coefficient of a relative channel equalizer of the corresponding receiving base station; performing equalization processing on the received signal on the basis of the tap coefficient to obtain an equalized signal; performing generalized cross-correlation computation on all equalized signals to obtain TDOA information between all the receiving base stations; and determining the location of the unmanned aerial vehicle on the basis of the TDOA information between all the receiving base stations. In the present invention, the influence of multipath effects is reduced by means of equalization processing, without the need to separate a main signal path and a reflected path, so that the solution of the present invention achieves lower signal processing complexity and also has smaller computational overhead.

Description

TDOA positioning methods, systems, and electronic devices based on channel estimation and channel equalization. Technical Field

[0001] This invention relates to the field of multi-station positioning, and in particular to a TDOA positioning method, system, and electronic device based on channel estimation and channel equalization. Background Technology

[0002] Multi-station positioning systems are widely used in specific applications such as military reconnaissance and surveillance, agriculture, and environmental monitoring due to their advantages such as high accuracy, reliability, and wide coverage.

[0003] However, in practical applications, signal transmission suffers from multipath effects. Multipath effects occur because wireless signals encounter obstacles (such as buildings, trees, and walls) during propagation, causing reflections that lengthen the signal propagation path and resulting in multiple signals reaching the receiving point via different paths. Positioning technology in multipath environments needs to consider the delay and strength differences of signals arriving at the receiving base station through different paths, and employs complex signal processing and optimization algorithms to improve positioning accuracy and stability.

[0004] Therefore, how to reduce the complexity of signal processing and algorithms required for positioning technology in multipath environments has become a technical problem that urgently needs to be solved in the industry. Summary of the Invention

[0005] This invention provides a TDOA positioning method, system, and electronic device based on channel estimation and channel equalization, which solves the technical problem of how to reduce the signal processing complexity and algorithm complexity required for positioning technology in multipath environments.

[0006] According to a first aspect of the present invention, embodiments of the present invention provide a TDOA positioning method based on channel estimation and channel equalization, which uses K receiving base stations to locate a UAV, where K is an integer greater than or equal to 2;

[0007] This multi-station positioning method includes:

[0008] Each receiving base station receives signals within its measurement range. If a pilot signal is received, first target data is generated, which includes the time-domain information of the pilot signal.

[0009] Based on the first target data, the pilot information of the pilot signal is obtained;

[0010] Based on the pilot information, the estimated channel time-domain response is obtained;

[0011] Based on the estimated channel time-domain response, the tap coefficients of the relative channel equalizer of the corresponding receiving base station are obtained;

[0012] Based on the tap coefficients, the received signal is subjected to equalization processing to obtain an equalized signal;

[0013] Perform generalized cross-correlation calculations on all the equalized signals to obtain TDOA information among all receiving base stations;

[0014] The location of the UAV is determined based on the TDOA information among all the receiving base stations.

[0015] Optionally, determining whether a pilot signal has been received includes:

[0016] Obtain the received signal data of the signal within the measurement range;

[0017] Based on the received signal data, the duration of the pilot signal and the transmission time interval of the pilot signal are obtained;

[0018] Based on the duration and the transmission time interval, it is determined whether the pilot signal has been received.

[0019] Optionally, based on the tap coefficients, the received signal is subjected to equalization processing to obtain an equalized signal, including:

[0020] Based on the aforementioned tap coefficients, a relative channel equalizer for the corresponding receiving base station is constructed.

[0021] The received signal is equalized using the relative channel equalizer to obtain an equalized signal.

[0022] Optionally, the relative channel equalizer is a linear equalizer.

[0023] Optionally, a generalized cross-correlation calculation is performed on all the equalized signals to obtain TDOA information among all receiving base stations, including:

[0024] Calculate the generalized cross-correlation function between the equalized signals;

[0025] Perform inverse Fourier transform on all the generalized cross-correlation functions to obtain the corresponding time-domain generalized cross-correlation functions;

[0026] Based on the maximum value of all the aforementioned time-domain generalized cross-correlation functions, the TDOA information among all receiving base stations is obtained.

[0027] Optionally, the location of the UAV is determined based on the TDOA information among all the receiving base stations, including:

[0028] Establish a rectangular coordinate system with any point in space as the origin, and obtain the coordinates of each receiving base station in the rectangular coordinate system;

[0029] Based on the coordinates of each receiving base station in the Cartesian coordinate system, and the TDOA information among all receiving base stations, the position coordinates of the UAV in the Cartesian coordinate system are determined.

[0030] According to a second aspect of the present invention, embodiments of the present invention provide a TDOA positioning system based on channel estimation and channel equalization, comprising:

[0031] There are K receiving base stations, each receiving signals within its measurement range, where K is an integer greater than or equal to 2;

[0032] The first target data generation module is used to generate first target data when a pilot signal is received, wherein the first target data includes the time domain information of the pilot signal;

[0033] The pilot information acquisition module is used to obtain the pilot information of the pilot signal based on the first target data;

[0034] The estimated channel time-domain response acquisition module is used to obtain the estimated channel time-domain response based on the pilot information;

[0035] The tap coefficient acquisition module is used to obtain the tap coefficients of the relative channel equalizer of the corresponding receiving base station based on the estimated channel time domain response.

[0036] The equalization signal acquisition module is used to perform equalization processing on the received signal based on the tap coefficients to obtain an equalization signal;

[0037] The TDOA information acquisition module is used to perform generalized cross-correlation calculation on all the equalization signals to obtain TDOA information between all receiving base stations;

[0038] The positioning module is used to determine the location of the UAV based on the TDOA information between all the receiving base stations.

[0039] Optionally, it also includes a pilot signal acquisition module, the pilot signal acquisition module comprising:

[0040] A received signal data acquisition unit is used to acquire received signal data of the signal within the measurement range;

[0041] The pilot signal information acquisition module is used to obtain the duration of the pilot signal and the transmission time interval of the pilot signal based on the received signal data.

[0042] The determination module is used to determine whether the pilot signal has been received based on the duration and the transmission time interval.

[0043] Optionally, the equalization signal acquisition module includes:

[0044] A relative channel equalizer construction unit is used to construct a relative channel equalizer for the corresponding receiving base station based on the tap coefficients.

[0045] The equalization processing module performs equalization processing on the received signal based on the relative channel equalizer to obtain an equalized signal.

[0046] According to a third aspect of the present invention, an embodiment of the present invention provides an electronic device including a TDOA positioning system as described in any of the second aspects of the present invention.

[0047] Compared with the prior art, the technical solution of the embodiments of the present invention has the following beneficial effects:

[0048] In the TDOA positioning method, system, and electronic device of this invention, K receiving base stations are used to locate the UAV. Each receiving base station receives signals within its measurement range. If a pilot signal is received, first target data is generated. Based on the first target data, pilot information of the pilot signal is obtained. Based on the pilot information, the estimated channel time-domain response is obtained. Based on the estimated channel time-domain response, the tap coefficients of the relative channel equalizer of the corresponding receiving base station are obtained. Based on the tap coefficients, the received signals are equalized to obtain equalized signals. Generalized cross-correlation calculation is performed on all equalized signals to obtain TDOA information among all receiving base stations. Based on the TDOA information among all receiving base stations, the position of the UAV is determined. This invention reduces the impact of multipath effects through equalization processing, eliminating the need to separate the main signal path and reflection path. This results in a solution with lower signal processing complexity and lower computational overhead, exhibiting strong robustness to TDOA in multipath environments. Attached Figure Description

[0049] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0050] Figure 1 is a schematic diagram of a system model of the TDOA positioning method according to an embodiment of the present invention;

[0051] Figure 2 is a flowchart illustrating a multi-station positioning method according to an embodiment of the present invention;

[0052] Figure 3 is a schematic diagram of the time-domain signal of the received signal data in one embodiment of the present invention;

[0053] Figure 4 is a schematic diagram of the positioning of a drone in one embodiment of the present invention;

[0054] Figure 5 is a block diagram of a TDOA positioning system according to an embodiment of the present invention;

[0055] Figure 6 is a block diagram of the equalization signal acquisition module in one embodiment of the present invention;

[0056] Explanation of reference numerals in the attached figures: 81-Receiving base station; 82-First target data generation module; 83-Pilot information acquisition module; 84-Estimated channel time domain response acquisition module; 85-Tap coefficient acquisition module; 86-Equalization signal acquisition module; 87-TDOA information acquisition module; 88-Location module; 861-Relative channel equalizer construction unit; 862-Equalization processing module. Detailed Implementation

[0057] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0058] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0059] The technical solution of the present invention will be described in detail below with reference to specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0060] As described in the background section, existing technologies struggle to reduce the complexity of signal processing and algorithms required for localization in multipath environments, which will be explained in detail below.

[0061] The common methods for locating multipath environments currently include the following:

[0062] 1.) TDOA Positioning:

[0063] TDOA (Time Difference of Arrival) locates signals by measuring the time difference of arrival between different receiving base stations. Using these time differences, the location of the signal source can be determined through geometric relationships. TDOA needs to handle multipath effects, separating direct paths from reflected paths. TDOA multipath algorithms, such as beamforming, polarization methods, and sparse reconstruction methods, typically suffer from high computational complexity. Furthermore, this method requires maintaining high clock synchronization among all receiving base stations, placing high demands on hardware.

[0064] 2) Received Signal Strength (RSS) location:

[0065] RSS (Resonant Signal Detection) measures the signal strength received by each receiver, estimates the distance to the receiving base station using a signal attenuation model, and then determines the location of the signal source using geometric methods. Compared to TDOA (Digital Transmission Over-The-Air) positioning, RSS does not require clock synchronization and only needs to measure signal strength, making it suitable for low-cost applications. However, due to multipath effects, RSS positioning may have significant errors.

[0066] 3) Angle of Arrival (AOA) Positioning

[0067] AOA (Aspect-Oriented Alignment) positioning uses the angles at which signals arrive at each receiver. This angular information allows for the determination of the signal source's location through geometric relationships. In multipath environments, AOA positioning requires the use of antenna arrays and advanced beamforming techniques to distinguish between direct and multipath signals. This method is suitable for multiple receiving base stations working collaboratively and does not rely on clock synchronization.

[0068] 4) Frequency Differential Arrival (FDOA) Positioning:

[0069] Frequency Differential Arrival (FDOA) uses the frequency offset of a signal at different receivers for localization. This frequency offset is caused by the Doppler effect; by measuring the frequency offset and combining it with known geometric positions, the location of the signal source can be calculated. In multipath environments, FDOA localization requires frequency estimation and filtering techniques to distinguish between direct and multipath signals.

[0070] 5) Hybrid positioning:

[0071] Hybrid positioning methods combine the advantages of multiple technologies mentioned above, improving positioning accuracy and robustness through multi-sensor fusion and the integration of various signal processing algorithms. For example, combining TDOA and AOA positioning methods can utilize both time and angle information simultaneously for more precise positioning.

[0072] In summary, positioning technology in multipath environments integrates multiple disciplines such as radio communication, signal processing, and photoelectric sensing. All of these technologies suffer from high complexity in signal processing and algorithms.

[0073] In view of this, embodiments of the present invention provide a TDOA positioning method, which utilizes K receiving base stations to locate a UAV. Each receiving base station receives signals within its measurement range. If a pilot signal is received, first target data is generated. Based on the first target data, pilot information of the pilot signal is obtained. Based on the pilot information, an estimated channel time-domain response is obtained. Based on the estimated channel time-domain response, the tap coefficients of the relative channel equalizer of the corresponding receiving base station are obtained. Based on the tap coefficients, the received signals are equalized to obtain equalized signals. Generalized cross-correlation calculation is performed on all equalized signals to obtain TDOA information among all receiving base stations. Based on the TDOA information among all receiving base stations, the position of the UAV is determined. The present invention reduces the impact of multipath effects through equalization processing, without needing to separate the main signal path and reflection path. This results in a solution with lower signal processing complexity and lower computational overhead, and strong robustness to TDOA in multipath environments.

[0074] To make the above-mentioned objectives, features and beneficial effects of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0075] This invention provides a TDOA positioning method based on channel estimation and channel equalization, which uses K receiving base stations to locate the UAV, where K is an integer greater than or equal to 2;

[0076] As an example, the system model of the TDOA positioning method of the present invention can be shown in Figure 1, where i is the index of the receiving base station and 0≤i≤K-1.

[0077] Please refer to Figure 2. This multi-station positioning method includes:

[0078] S1: Each receiving base station receives signals within its measurement range. If a pilot signal is received, first target data is generated, which includes the time-domain information of the pilot signal.

[0079] S2: Based on the first target data, obtain the pilot information of the pilot signal;

[0080] S3: Based on the pilot information, obtain the estimated channel time-domain response;

[0081] S4: Based on the estimated channel time-domain response, obtain the tap coefficients of the relative channel equalizer of the corresponding receiving base station;

[0082] S5: Based on the tap coefficients, perform equalization processing on the received signal to obtain an equalized signal;

[0083] S6: Perform generalized cross-correlation calculation on all the equalization signals to obtain TDOA information between all receiving base stations;

[0084] S7: Determine the location of the UAV based on the TDOA information between all the receiving base stations.

[0085] Equalization processing of the received signals can be understood as equalizing the overall signal received within the measurement range of each receiving base station. This overall signal includes the pilot signal and the signal carrying information after the pilot.

[0086] In summary, this invention fully utilizes equalization techniques to achieve accurate TDOA positioning in multipath environments. It estimates the relative channel information using pilot information and eliminates the influence of reflection paths using equalization techniques, thereby eliminating TDOA estimation errors caused by multipath effects. Based on this, the system uses generalized cross-correlation (GCC) to estimate the TDOA information at this time, which is relatively accurate. It can be seen that the method provided by this invention is applicable to TDOA in multipath environments and has strong robustness.

[0087] The method of the present invention will now be further described.

[0088] Please refer to Figures 2 and 3, and perform step S1.

[0089] S1: Each receiving base station receives signals within its measurement range. If a pilot signal is received, first target data is generated, which includes the time-domain information of the pilot signal.

[0090] In one implementation, determining whether a pilot signal has been received includes:

[0091] Obtain the received signal data of the signal within the measurement range;

[0092] Specifically, a schematic diagram of the time-domain signal s(t) of the received signal data can be shown in Figure 3. In the example in Figure 3, the beginning of each signal segment carries a repeating pilot signal p(t), where T p T represents the duration of each pilot signal segment. s It is the time interval between two adjacent pilot signals.

[0093] Based on the received signal data, the duration of the pilot signal and the transmission time interval of the pilot signal are obtained;

[0094] Based on the duration and the transmission time interval, it is determined whether the pilot signal has been received.

[0095] The first target data will now be described:

[0096] In a multipath environment, the signal received by base station i can be represented as:

[0097] This signal can be considered as the first target data, including the time-domain information of the pilot signal, where h i (t) represents the time-domain channel response received at base station i, n i (t) represents the time-domain Gaussian white noise at base station i, Γ i It is the set of path delays for receiving base station i.

[0098] Due to path delays, the received signal from the receiving base station is independent of the transmitted signal within a certain time period. Therefore, the received signal data on base station i...

[0099] Where, τ i To receive the actual delay of the direct path on base station i, n i (t) represents the time-domain Gaussian white noise at the receiving base station i, Γ' i It is the set of relative delays between each path and the direct path at receiving base station i; g i (t)=h i (t+τ i ) is the time-domain relative channel response after shifting, h i (t) represents the time-domain channel response received at base station i, where i is an integer and 0 ≤ i ≤ K-1.

[0100] Please refer to Figure 2 and perform step S2.

[0101] S2: Based on the first target data, obtain the pilot information of the pilot signal.

[0102] Specifically, based on the first target data r i (t), obtain the pilot information p of the pilot signal. i (t).

[0103] Please refer to Figure 2 and proceed to step S3.

[0104] S3: Based on the pilot information, obtain the estimated channel time domain response.

[0105] Because of receiving r i The pilot information p received in (t) i (t) can be written as: p i (t)=p(t)*g i (t)

[0106] Therefore, in one specific implementation, step S3 includes:

[0107] Based on the pilot information p i Using the pilot signal p(t) and the pilot signal p(t), the estimated channel time-domain response is obtained.

[0108] Please refer to Figure 2 and proceed to step S4.

[0109] S4: Based on the estimated channel time-domain response, obtain the tap coefficients of the relative channel equalizer of the corresponding receiving base station.

[0110] Specifically, based on the estimated channel time-domain response Directly obtain the tap coefficients c of the relative channel equalizer of the corresponding receiving base station. i (t).

[0111] It should be understood that the present invention will adjust the quantity based on each received data. The tap coefficients c of the relative channel equalizer of the corresponding receiving base station are adjusted according to the different conditions. i (t).

[0112] Therefore, this invention solves the problem of multiple peaks and ambiguity in the direct GCC delay estimation of signals received by the base station.

[0113] Please refer to Figure 2 and proceed to step S5.

[0114] S5: Based on the tap coefficients, perform equalization processing on the received signal to obtain an equalized signal.

[0115] In one embodiment, a method for equalizing a received signal based on the tap coefficients to obtain an equalized signal includes:

[0116] Based on the aforementioned tap coefficients, a relative channel equalizer for the corresponding receiving base station is constructed.

[0117] The received signal is equalized based on the relative channel equalizer to obtain an equalized signal.

[0118] Specifically, the equalized signal y corresponding to base station i i (t)=r i (t)*c i (t).

[0119] In one specific implementation, the relative channel equalizer is a linear equalizer. This invention leverages the advantages of linear equalizers, such as simple structure and low computational cost, to reduce the computational load during positioning.

[0120] Please refer to Figure 2 and proceed to step S6.

[0121] S6: Perform generalized cross-correlation calculation on all the equalized signals to obtain TDOA information among all receiving base stations.

[0122] In one implementation, a generalized cross-correlation calculation is performed on all the equalization signals to obtain TDOA information among all receiving base stations, including:

[0123] Calculate the generalized cross-correlation function between the equalized signals;

[0124] As an example, the generalized cross-correlation function between receiving base station i and receiving base station j

[0125] Where i and j represent the indices of the base stations (i, j = 0, ..., K-1), X i (f), X j (f) represents the Fourier transform of the received signal, (·) * Indicates conjugate.

[0126] Perform inverse Fourier transform on all the generalized cross-correlation functions to obtain the corresponding time-domain generalized cross-correlation functions;

[0127] Specifically, for the generalized cross-correlation function R ij (f) Perform an inverse Fourier transform to obtain the generalized cross-correlation function r in the time domain. ij (τ), where,

[0128] Based on the maximum value of all the aforementioned time-domain generalized cross-correlation functions, the TDOA information among all receiving base stations is obtained;

[0129] Specifically, the generalized cross-correlation function r is obtained. ij The time delay τ corresponding to the maximum value of (τ) ij Thus, the time difference of signal arrival is obtained, where τ ij =argmax[r ij (τ)。

[0130] Please refer to Figures 1 and 2, and proceed to step S7.

[0131] S7: Determine the location of the UAV based on the TDOA information between all the receiving base stations.

[0132] In one embodiment, a method for determining the location of the UAV based on TDOA information among all receiving base stations includes:

[0133] Establish a rectangular coordinate system with any point in space as the origin, and obtain the coordinates of each receiving base station in the rectangular coordinate system;

[0134] Based on the coordinates of each receiving base station in the Cartesian coordinate system, and the TDOA information among all receiving base stations, the position coordinates of the UAV in the Cartesian coordinate system are determined.

[0135] Specifically, taking the four base stations in Figure 1 as an example, by substituting the known three-dimensional coordinates of each base station and the coordinates of the unknown signal source, three sets of nonlinear equations related to distance can be listed. The coordinates of base station A are (x... A y A , z A The coordinates of base station B are (x...). B y B , z B The coordinates of base station C are (x...). C y C , z C The coordinates of base station D are (x...). D y D , z D The coordinates of the drone are (x, y, z).

[0136] The distances from base station A to other base stations B, C, and D are respectively c*TDOA. AB c*TDOA AC c*TDOA AD In this case, the three nonlinear equations related to distance are:

[0137] Equation 1: √((xx) B ) 2 +(yy B ) 2 +(zz B ) 2 )-√((xx A ) 2 +(yy A ) 2 +(zz A ) 2 )=c*TDOA AB

[0138] Equation 2: √((xx) C ) 2 +(yy C ) 2 +(zz C ) 2 )-√((xx A ) 2 +(yy A ) 2 +(zz A ) 2 )=c*TDOA AC

[0139] Equation 3: √((xx) D ) 2 +(yyD ) 2 +(zz D ) 2 )-√((xx A ) 2 +(yy A ) 2 +(zz A ) 2 )=c*TDOA AD

[0140] Where c is the speed of light.

[0141] The position coordinates of the UAV in the Cartesian coordinate system can be determined by solving these three equations using numerical methods, such as the nonlinear least squares method.

[0142] It should be understood that the present invention is not limited to this, and other TDOA positioning methods are also possible. Since TDOA positioning methods are relatively common existing technologies, the present invention will not elaborate on them here.

[0143] Please refer to Figures 2 and 4 for further explanation of the positioning effect of the present invention:

[0144] Figure 4 shows a schematic diagram of the drone's positioning. The example in Figure 4 uses four receiving base stations for positioning, and the positioning area has been enlarged.

[0145] The circle symbol can be interpreted as the location of a base station;

[0146] The cross symbol can be understood as the actual location;

[0147] The cross symbol can be understood as the current technology for locating the drone;

[0148] The diamond symbol can be understood as representing the location of the drone by the method of this invention.

[0149] As we can see, the position of the balanced TDOA positioning (cross symbol) is closer to the actual position of the UAV (cross symbol), indicating better positioning performance.

[0150] In summary, this invention reduces the impact of multipath effects through equalization processing, eliminating the need to separate the main signal path and the reflection path. This results in a solution with lower signal processing complexity, lower computational overhead, strong robustness to TDOA in multipath environments, and correspondingly lower hardware costs.

[0151] Furthermore, referring to Figure 5, this embodiment of the invention also provides a TDOA positioning system based on channel estimation and channel equalization, including:

[0152] K receiving base stations 81, each receiving signals within its measurement range, where K is an integer greater than or equal to 2;

[0153] The first target data generation module 82 is used to generate first target data when a pilot signal is received, wherein the first target data includes the time domain information of the pilot signal;

[0154] Pilot information acquisition module 83 is used to obtain pilot information of the pilot signal based on the first target data;

[0155] The estimated channel time-domain response acquisition module 84 is used to obtain the estimated channel time-domain response based on the pilot information;

[0156] The tap coefficient acquisition module 85 is used to obtain the tap coefficients of the relative channel equalizer of the corresponding receiving base station 81 based on the estimated channel time domain response.

[0157] The equalization signal acquisition module 86 is used to perform equalization processing on the received signal based on the tap coefficients to obtain an equalization signal;

[0158] The TDOA information acquisition module 87 is used to perform generalized cross-correlation calculation on all the equalization signals to obtain TDOA information between all receiving base stations 81.

[0159] The positioning module 88 is used to determine the location of the UAV based on the TDOA information between all the receiving base stations 81.

[0160] In one embodiment, referring to FIG6, the equalization signal acquisition module 86 includes:

[0161] The relative channel equalizer construction unit 861 is used to construct the relative channel equalizer of the corresponding receiving base station 81 based on the tap coefficients.

[0162] The equalization processing module 862 performs equalization processing on the received signal based on the relative channel equalizer to obtain an equalized signal.

[0163] As can be seen, the acquisition module of this invention reduces the impact of multipath effects through equalization processing, without the need to separate the main signal path and the reflection path. This makes the solution of this invention less complex in signal processing and has lower computational overhead, and has strong robustness to TDOA in multipath environments.

[0164] [Corrected from Rule 91, 01.08.2025] In a preferred embodiment, the TDOA positioning system further includes a pilot signal acquisition module, the pilot signal acquisition module comprising:

[0165] A received signal data acquisition unit is used to acquire received signal data of the signal within the measurement range;

[0166] The pilot signal information acquisition module is used to obtain the duration of the pilot signal and the transmission time interval of the pilot signal based on the received signal data.

[0167] The determination module is used to determine whether the pilot signal has been received based on the duration and the transmission time interval.

[0168] In addition, embodiments of the present invention also provide an electronic device including the above-mentioned TDOA positioning system. For example, the electronic device can be an antenna base station, etc. Of course, the present invention is not limited to this and can also be other devices that require TDOA positioning.

[0169] In summary, this embodiment of the invention utilizes K receiving base stations to locate a UAV. Each receiving base station receives signals within its measurement range. If a pilot signal is received, first target data is generated. Based on the first target data, pilot information of the pilot signal is obtained. Based on the pilot information, the estimated channel time-domain response is obtained. Based on the estimated channel time-domain response, the tap coefficients of the relative channel equalizer of the corresponding receiving base station are obtained. Based on the tap coefficients, the received signal is equalized to obtain an equalized signal. Generalized cross-correlation calculation is performed on all equalized signals to obtain TDOA information among all receiving base stations. Based on the TDOA information among all receiving base stations, the position of the UAV is determined. This invention reduces the impact of multipath effects through equalization processing, eliminating the need to separate the main signal path and reflection path. This results in a solution with lower signal processing complexity and lower computational overhead, exhibiting strong robustness to TDOA in multipath environments.

[0170] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A TDOA positioning method based on channel estimation and channel equalization, characterized in that, The drone is located using K receiving base stations, where K is an integer greater than or equal to 2; This multi-station positioning method includes: Each receiving base station receives signals within its measurement range. If a pilot signal is received, first target data is generated, which includes the time-domain information of the pilot signal. Based on the first target data, the pilot information of the pilot signal is obtained; Based on the pilot information, the estimated channel time-domain response is obtained; Based on the estimated channel time-domain response, the tap coefficients of the relative channel equalizer of the corresponding receiving base station are obtained; Based on the tap coefficients, the received signal is subjected to equalization processing to obtain an equalized signal; Perform generalized cross-correlation calculations on all the equalized signals to obtain TDOA information among all receiving base stations; The location of the UAV is determined based on the TDOA information among all the receiving base stations.

2. The TDOA positioning method as described in claim 1, characterized in that, Determining whether a pilot signal has been received includes: Obtain the received signal data of the signal within the measurement range; Based on the received signal data, the duration of the pilot signal and the transmission time interval of the pilot signal are obtained; Based on the duration and the transmission time interval, it is determined whether the pilot signal has been received.

3. The TDOA positioning method as described in claim 1, characterized in that, Based on the tap coefficients, the received signal is subjected to equalization processing to obtain an equalized signal, including: Based on the aforementioned tap coefficients, a relative channel equalizer for the corresponding receiving base station is constructed. The received signal is equalized using the relative channel equalizer to obtain an equalized signal.

4. The TDOA positioning method as described in claim 3, characterized in that, The relative channel equalizer is a linear equalizer.

5. The TDOA positioning method as described in claim 1, characterized in that, Perform generalized cross-correlation calculations on all the aforementioned equalization signals to obtain TDOA information among all receiving base stations, including: Calculate the generalized cross-correlation function between the equalized signals; Perform inverse Fourier transform on all the generalized cross-correlation functions to obtain the corresponding time-domain generalized cross-correlation functions; Based on the maximum value of all the aforementioned time-domain generalized cross-correlation functions, the TDOA information among all receiving base stations is obtained.

6. The TDOA positioning method as described in claim 1, characterized in that, Based on the TDOA information among all the receiving base stations, the location of the UAV is determined, including: Establish a rectangular coordinate system with any point in space as the origin, and obtain the coordinates of each receiving base station in the rectangular coordinate system; Based on the coordinates of each receiving base station in the Cartesian coordinate system, and the TDOA information among all receiving base stations, the position coordinates of the UAV in the Cartesian coordinate system are determined.

7. A TDOA positioning system based on channel estimation and channel equalization, characterized in that, include: There are K receiving base stations, each receiving signals within its measurement range, where K is an integer greater than or equal to 2; The first target data generation module is used to generate first target data when a pilot signal is received, wherein the first target data includes the time domain information of the pilot signal; The pilot information acquisition module is used to obtain the pilot information of the pilot signal based on the first target data; The estimated channel time-domain response acquisition module is used to obtain the estimated channel time-domain response based on the pilot information; The tap coefficient acquisition module is used to obtain the tap coefficients of the relative channel equalizer of the corresponding receiving base station based on the estimated channel time domain response. The equalization signal acquisition module is used to perform equalization processing on the received signal based on the tap coefficients to obtain an equalization signal; The TDOA information acquisition module is used to perform generalized cross-correlation calculation on all the equalization signals to obtain TDOA information between all receiving base stations; The positioning module is used to determine the location of the UAV based on the TDOA information between all the receiving base stations.

8. The TDOA positioning system as described in claim 7, characterized in that, It also includes a pilot signal acquisition module, which includes: A received signal data acquisition unit is used to acquire received signal data of the signal within the measurement range; The pilot signal information acquisition module is used to obtain the duration of the pilot signal and the transmission time interval of the pilot signal based on the received signal data. The determination module is used to determine whether the pilot signal has been received based on the duration and the transmission time interval.

9. The TDOA positioning system as described in claim 7, characterized in that, The equalization signal acquisition module includes: A relative channel equalizer construction unit is used to construct a relative channel equalizer for the corresponding receiving base station based on the tap coefficients. The equalization processing module performs equalization processing on the received signal based on the relative channel equalizer to obtain an equalized signal.

10. An electronic device, characterized in that, Including the TDOA positioning system as described in any one of claims 7 to 9.

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