Train positioning methods, devices, electronic equipment and storage media

Abstract

This invention provides a train positioning method, device, electronic device, and storage medium, relating to the field of rail transit technology. The method includes: determining multiple target positioning information within a preset search range based on a preset error search interval and using the train's positioning information feedback value as the search center; determining the signal integral energy value corresponding to each target positioning information; determining the Doppler frequency shift abrupt change position based on the signal integral energy value corresponding to each target positioning information; adjusting the tracking loop based on the Doppler frequency shift abrupt change position, and determining the train's position information through the adjusted tracking loop. This invention, by using the train's positioning information feedback value as the search center and performing a local error search within a preset search range, can accurately determine the Doppler frequency shift abrupt change position, thereby reducing the impact of Doppler frequency shift abrupt changes on the tracking loop and improving the tracking loop's positioning accuracy for the train.

Description

Technical Field

[0001] This invention relates to the field of rail transit technology, and in particular to a train positioning method, device, electronic equipment, and storage medium. Background Technology

[0002] In recent years, with the widespread adoption of high-speed trains, train safety has become an increasingly important issue, making the realization of high-precision positioning for high-speed trains of great significance.

[0003] In tunnel train positioning scenarios, the narrowness of the tunnel limits the height at which base stations can be deployed. When a train passes a base station at high speed, the small vertical distance between the base station and the train causes a severe Doppler frequency shift, which significantly affects the positioning accuracy of traditional tracking loops. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention provides a train positioning method, device, electronic device, and storage medium.

[0005] In a first aspect, the present invention provides a train positioning method, comprising:

[0006] Based on a preset error search interval, the positioning information of multiple targets within a preset search range is determined using the train's positioning information feedback value as the search center.

[0007] Determine the signal integral energy value corresponding to each target positioning information;

[0008] Based on the signal integral energy value corresponding to each target positioning information, the location of the Doppler frequency shift abrupt change is determined;

[0009] The tracking loop is adjusted based on the location of the Doppler frequency shift abrupt change, and the train's position information is determined through the adjusted tracking loop.

[0010] Optionally, according to a train positioning method provided by the present invention, determining the location of the Doppler frequency shift abrupt change based on the signal integral energy value corresponding to each target positioning information includes:

[0011] The signal integral energy value corresponding to each target positioning information is fitted to determine the maximum signal integral energy value;

[0012] The position corresponding to the maximum signal integral energy value is determined as the position of the Doppler frequency shift abrupt change.

[0013] Optionally, according to a train positioning method provided by the present invention, determining the signal integral energy value corresponding to each target positioning information includes:

[0014] Determine the local copy signal of the train receiver corresponding to each target positioning information;

[0015] Based on the current received signal of the train receiver and the locally copied signal of the train receiver corresponding to each target positioning information, the signal integral energy value corresponding to each target positioning information is determined.

[0016] Optionally, according to a train positioning method provided by the present invention, determining the signal integral energy value corresponding to each target positioning information based on the current received signal of the train receiver and the locally copied signal of the train receiver corresponding to each target positioning information includes:

[0017] The train receiver locally copied signal corresponding to the received signal and each target positioning information is subjected to correlation calculation to obtain multiple correlation result values, and the multiple correlation result values ​​correspond one-to-one with the multiple target positioning information;

[0018] Based on each relevant result value, determine the signal integral energy value corresponding to each target positioning information.

[0019] Optionally, according to a train positioning method provided by the present invention, determining the train receiver local copy signal corresponding to each target positioning information includes:

[0020] Determine the distance between the train receiver and the target base station, wherein the target base station is the base station closest to the train receiver;

[0021] Based on the relationship between the carrier phase difference and the distance, the carrier phase difference corresponding to each target positioning information is determined;

[0022] Based on the carrier phase difference, the train receiver local copy signal corresponding to each target positioning information is determined.

[0023] Optionally, according to a train positioning method provided by the present invention, the expression for the relationship between the carrier phase difference and the distance is:

[0024] φ=λ -1 r+N

[0025] Where φ represents the carrier phase difference, r represents the distance, λ represents the carrier wavelength, and N represents the periodic ambiguity.

[0026] In a second aspect, the present invention also provides a train positioning device, comprising:

[0027] The first determining module is used to determine the positioning information of multiple targets within a preset search range based on a preset error search interval and with the train's positioning information feedback value as the search center.

[0028] The second determining module is used to determine the signal integral energy value corresponding to each target positioning information;

[0029] The third determining module is used to determine the location of the Doppler frequency shift abrupt change based on the signal integral energy value corresponding to each target positioning information;

[0030] The fourth determining module is used to adjust the tracking loop based on the position of the Doppler frequency shift abrupt change, and to determine the position information of the train through the adjusted tracking loop.

[0031] Thirdly, the present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the train positioning method as described in the first aspect.

[0032] Fourthly, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the train positioning method as described in the first aspect.

[0033] Fifthly, the present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the train positioning method as described in the first aspect.

[0034] The train positioning method, device, electronic equipment, and storage medium provided by this invention, by using the train's positioning information feedback value as the search center, performs local error search within a preset search range, and accurately determines the location of Doppler frequency shift abrupt changes based on the signal integral energy values ​​corresponding to multiple target positioning information within the preset search range. This reduces the impact of Doppler frequency shift abrupt changes on the tracking loop and improves the positioning accuracy of the tracking loop for the train. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in this 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 some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the sudden Doppler frequency shift when the train receiver passes a base station, as provided by the present invention.

[0037] Figure 2 This is a schematic diagram illustrating the impact of train receiver positioning error on the prediction of Doppler frequency change location provided by the present invention;

[0038] Figure 3This is a flowchart illustrating the train positioning method provided by the present invention;

[0039] Figure 4 This is a schematic diagram of signal integral energy fitting provided by the present invention;

[0040] Figure 5 This is one of the structural schematic diagrams of the train positioning system provided by the present invention;

[0041] Figure 6 This is the second structural schematic diagram of the train positioning system provided by the present invention;

[0042] Figure 7 This is a schematic diagram of the train positioning device provided by the present invention;

[0043] Figure 8 This is a schematic diagram of the physical structure of the electronic device provided by the present invention. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0045] To facilitate a clearer understanding of the various embodiments of the present invention, some relevant background knowledge will be introduced as follows.

[0046] In traditional high-precision train positioning methods, the carrier phase measurement value between the train receiver and the base station is defined as... This study investigates the impact of Doppler shifts on positioning accuracy, specifically how Doppler frequency shifts affect carrier phase measurements. The formula for defining carrier phase measurements is:

[0047]

[0048] in, To replicate the phase of the carrier signal for the train receiver; This refers to the phase of the carrier signal transmitted by the base station. Due to the relative motion between the train and the base station, the Doppler effect occurs, causing variations in the measured carrier phase value. The changes.

[0049] Let f be the frequency of the carrier signal transmitted by the base station, and let f be the Doppler frequency shift caused by the Doppler effect between the train receiver and the base station. d Then the carrier signal frequency f received by the train receiver r for:

[0050] f r =f+f d

[0051] Integral Doppler It is the Doppler frequency shift f d The integral over time, i.e.:

[0052]

[0053] Where dφ k This represents the integrated Doppler measurement output by the train receiver at the k-th epoch. Integrating the Doppler frequency shift is equivalent to counting the carrier phase change caused by the Doppler frequency shift in cycles. Therefore, the integrated Doppler dφ at the k-th epoch... k This is equivalent to the change in carrier phase measurement from epoch 0 to epoch k.

[0054] In a traditional tracking loop, the carrier phase measurement value These are not the baseline measurements for the tracking loop; they are generally integrated Doppler measurements. (that is, the aforementioned dφ) k Or integral Doppler The values ​​are supplemented with integer numbers of cycles to obtain the carrier phase measurement. Output. Typically, the input signal to the tracking loop is defined as u. i (t), the train receiver locally replicates the signal as u o (t):

[0055] u i (t)=U i sin(ω i t+θ i )

[0056] u o (t)=U o cos(ω o t+θ o )

[0057] Among them, U i ω represents the carrier amplitude of the input signal to the tracking loop. i θ represents the carrier frequency of the input signal to the tracking loop. i U represents the initial phase of the input signal to the tracking loop. o ω represents the carrier amplitude of the locally replicated signal in the train receiver. o θ represents the carrier frequency of the locally replicated signal in the train receiver. o This indicates the initial phase of the signal locally copied by the train receiver.

[0058] The tracking loop input signal u i (t) and the train receiver's locally copied signal u o (t) Perform coherent integration to obtain the coherent integral value u. d (t):

[0059] u d (t)=U i U o {sin[(ω i +ω o )t+θ i +θ o ]+sin[(ω i -ω0)t+θ i -θ o ]}

[0060] coherent integral value u d (t) The low-pass filter value u can be obtained after passing through the low-pass filter. d ′ (t):

[0061] u d ′ (t)=U i U o {sin[ω e t+θ e ]}

[0062] Where ω e and θ e These are the carrier frequency difference and initial phase difference between the tracking loop input signal and the locally replicated signal from the train receiver, respectively:

[0063] ω e =ω i -ω0

[0064] θ e =θ i -θ o

[0065] low-pass filter value u d ′ (t) The phase difference between the tracking loop input signal and the locally copied signal from the train receiver is obtained through the discriminator.

[0066]

[0067] The phase difference between the aforementioned tracking loop input signal and the locally replicated signal of the train receiver This is equivalent to the integral Doppler effect generated between the train receiver and the base station.

[0068] The above derivation clearly shows the relationship between the carrier phase measurement and the tracking loop output. Therefore, the tracking stability and the magnitude of the tracking error of the tracking loop greatly affect the accuracy of train positioning.

[0069] In tunnel train positioning scenarios, the tunnel environment is narrow, and the height of the base station deployment is limited. When a train passes a base station at high speed, due to the small vertical distance between the base station and the train, a significant abrupt change occurs in the integrated Doppler reading between the train receiver and the passed base station. Figure 1 This is a schematic diagram of the sudden Doppler frequency shift when the train receiver passes a base station, as provided by the present invention. Figure 1 As shown, the horizontal axis represents time in milliseconds, and the vertical axis represents Doppler frequency shift in Hertz. In this case, the receiver often cannot use a traditional tracking loop for stable, high-precision positioning; the dynamics of the tracking loop and its stability when the integral Doppler shifts abruptly.

[0070] Traditional tracking loops, when faced with extremely short-duration abrupt changes in the integral Doppler value, experience a sudden increase in carrier phase error, potentially leading to loss of lock. This severely impacts accurate train positioning, primarily because typical tracking loops cannot withstand excessively high Doppler frequency shift rates. Furthermore, factors such as the signal propagation environment and inherent errors in the train receiver itself typically introduce some degree of error into the train positioning results. Figure 2 This is a schematic diagram illustrating the impact of train receiver positioning error on Doppler frequency change location prediction, as provided by the present invention. Figure 2 As shown, the horizontal axis represents time in milliseconds, and the vertical axis represents Doppler frequency shift in Hertz. When the positioning result leads the true value, this error may cause the receiver to predict the position of the Doppler frequency change too early, resulting in the tracking loop processing the Doppler frequency change prematurely without processing the actual Doppler frequency change. When the positioning result lags behind the true value, this error may cause the receiver to predict the position of the Doppler frequency change too late, resulting in the tracking loop not processing the actual Doppler frequency change. Both of these situations significantly reduce the train receiver's prediction accuracy of the Doppler frequency change position, thereby reducing the tracking loop's positioning accuracy for the train.

[0071] To overcome the above-mentioned defects, the present invention provides a train positioning method, device, electronic device, and storage medium. The following is in conjunction with... Figures 3-7 This invention describes the train positioning method, apparatus, electronic device, and storage medium provided by the present invention.

[0072] Figure 3 This is a flowchart illustrating the train positioning method provided by the present invention, as shown below. Figure 3 As shown, the method includes:

[0073] Step 300: Based on the preset error search interval, determine the positioning information of multiple targets within the preset search range using the train's positioning information feedback value as the search center;

[0074] Step 310: Determine the signal integral energy value corresponding to each target positioning information;

[0075] Step 320: Determine the location of the Doppler frequency shift abrupt change based on the signal integral energy value corresponding to each target positioning information;

[0076] Step 330: Adjust the tracking loop based on the Doppler frequency shift abrupt change position, and determine the train's position information through the adjusted tracking loop.

[0077] It should be noted that the executing entity of the train positioning method provided in this embodiment of the invention can be any electronic device or computer device, such as a mobile phone, tablet computer, laptop computer, PDA, etc. The following describes the technical solution of this embodiment of the invention in detail using a train positioning system as the executing entity.

[0078] Specifically, in this embodiment of the invention, in order to overcome the defect that Doppler frequency shift abrupt changes can seriously affect the positioning accuracy of the tracking loop in the scenario of train positioning in tunnels, this invention uses the train's positioning information feedback value as the search center and performs local error search within a preset search range. Based on the signal integral energy values ​​corresponding to the positioning information of multiple targets within the preset search range, the location of the Doppler frequency shift abrupt change can be accurately determined, thereby reducing the impact of the Doppler frequency shift abrupt change on the tracking loop and improving the positioning accuracy of the tracking loop for the train.

[0079] Optionally, the train's positioning information feedback value can be determined first. This positioning information feedback value is the positioning result of the train receiver at the current moment.

[0080] Optionally, the positioning information feedback value of the train can be used as the search center to determine the positioning information of multiple targets within a preset search range based on a preset error search interval.

[0081] For example, the train's positioning information feedback value Then use the location information feedback value Centered on a preset search area, the search range is divided based on a preset error search interval Δx. The division points represent the target location information. For example, the target location information might be:

[0082]

[0083] Where i represents the location index of the target positioning information, Δx represents the preset error search interval, and M openThis determines the refined preset search range, where k represents the kth epoch.

[0084] Optionally, the preset error search interval can be adaptively set based on actual applications, and the embodiments of the present invention do not impose specific limitations on this.

[0085] Optionally, the preset search range can be adaptively set based on actual applications, and the embodiments of the present invention do not specifically limit this.

[0086] Optionally, after determining the positioning information of multiple targets within a preset search range, the signal integral energy value corresponding to each target positioning information can be determined. Then, the Doppler frequency shift change position is determined based on the signal integral energy value corresponding to each target positioning information. At this time, the determined Doppler frequency shift change position is the most accurate positioning information within the preset search range. Further, the tracking loop can be adjusted based on the accurate Doppler frequency shift change position to reduce the impact of the Doppler frequency shift change on the tracking loop. Thus, the position information of the train can be accurately determined through the adjusted tracking loop.

[0087] The train positioning method provided by this invention uses the train's positioning information feedback value as the search center to perform local error search within a preset search range. Based on the signal integral energy values ​​corresponding to multiple target positioning information within the preset search range, the location of Doppler frequency shift abrupt changes can be accurately determined, thereby reducing the impact of Doppler frequency shift abrupt changes on the tracking loop and improving the positioning accuracy of the tracking loop for the train.

[0088] Optionally, determining the location of the Doppler frequency shift abrupt change based on the signal integral energy value corresponding to each target positioning information includes:

[0089] The signal integral energy value corresponding to each target positioning information is fitted to determine the maximum signal integral energy value;

[0090] The position corresponding to the maximum signal integral energy value is determined as the position of the Doppler frequency shift abrupt change.

[0091] Specifically, in this embodiment of the invention, after determining the signal integral energy value corresponding to each target positioning information, all signal integral energy values ​​can be fitted, and the maximum signal integral energy value can be determined based on the fitted curve. Then, the position corresponding to the maximum signal integral energy value is determined as the position of the Doppler frequency shift change.

[0092] Optionally, the specific method for fitting all signal integral energy values ​​in this invention is not specifically limited.

[0093] It is understandable that, due to the autocorrelation between the pseudo-code signal received by the train receiver and the pseudo-code signal locally copied by the train receiver, the signal power or the integrated energy value of the signal is maximized when the locally copied signal of the train receiver is completely matched or identical to the received signal of the train receiver. Therefore, in this embodiment of the invention, the position corresponding to the maximum integrated energy value is determined as the Doppler frequency shift change position. The determined Doppler frequency shift change position is the most accurate positioning information within the preset search range. Further adjusting the tracking loop based on the accurate Doppler frequency shift change position can reduce the impact of the Doppler frequency shift change on the tracking loop, and thus the adjusted tracking loop can accurately determine the position information of the train.

[0094] The train positioning method provided by this invention determines the maximum signal integral energy value by fitting the signal integral energy value corresponding to each target positioning information. The location of the maximum signal integral energy value is then determined as the Doppler frequency shift change location, which improves the accuracy of the Doppler frequency shift change location. This reduces the impact of the Doppler frequency shift change on the tracking loop and improves the positioning accuracy of the tracking loop for the train.

[0095] Optionally, determining the signal integral energy value corresponding to each target positioning information includes:

[0096] Determine the local copy signal of the train receiver corresponding to each target positioning information;

[0097] Based on the current received signal of the train receiver and the locally copied signal of the train receiver corresponding to each target positioning information, the signal integral energy value corresponding to each target positioning information is determined.

[0098] Specifically, in this embodiment of the invention, after determining multiple target positioning information within a preset search range, the train receiver local copy signal corresponding to each target positioning information can be determined, and then the signal integral energy value corresponding to each target positioning information can be determined based on the current received signal of the train receiver and the train receiver local copy signal corresponding to each target positioning information.

[0099] For example, determining the target location information X with location index i. i，k The corresponding train receiver local copy signal is represented as:

[0100]

[0101]

[0102] in, ω represents the initial value of the carrier phase. i , k For Xi，k The corresponding carrier angular frequency, c local Let T represent the local code, n represent the corresponding position of the train receiver's locally copied signal and the train receiver's locally copied pseudo-code signal, τ represent the code phase difference between the train receiver's locally copied signal and the train receiver's locally copied pseudo-code signal, and T represent the local code. s S represents the sampling period. I (n) and S Q (n) represent the locally copied signals of the train receivers for paths I and Q, respectively.

[0103] Optionally, the signal integral energy value corresponding to each target positioning information can be determined based on the current received signal of the train receiver and the locally copied signal of the train receiver corresponding to each target positioning information.

[0104] The train positioning method provided by this invention determines the signal integral energy value corresponding to each target positioning information by using the current received signal of the train receiver and the locally copied signal of the train receiver corresponding to each target positioning information. This facilitates the accurate determination of the Doppler frequency shift change position based on the signal integral energy value corresponding to each target positioning information, thereby reducing the impact of Doppler frequency shift changes on the tracking loop and improving the positioning accuracy of the tracking loop for the train.

[0105] Optionally, determining the signal integral energy value corresponding to each target positioning information based on the current received signal of the train receiver and the locally copied signal of the train receiver corresponding to each target positioning information includes:

[0106] The train receiver locally copied signal corresponding to the received signal and each target positioning information is subjected to correlation calculation to obtain multiple correlation result values, and the multiple correlation result values ​​correspond one-to-one with the multiple target positioning information;

[0107] Based on each relevant result value, determine the signal integral energy value corresponding to each target positioning information.

[0108] Specifically, in this embodiment of the invention, correlation operations can be performed on the currently received signal of the train receiver and the locally copied signal of the train receiver corresponding to each target positioning information to obtain multiple correlation result values. Each of the multiple correlation result values ​​corresponds one-to-one with multiple target positioning information. Then, based on each correlation result value, the signal integral energy value corresponding to each target positioning information is determined.

[0109] For example, the current received signal and target positioning information X of the train receiver. i，k The corresponding correlation result value output by the train receiver after performing correlation calculations on the locally copied signal is:

[0110]

[0111]

[0112] Where, τ k ω represents the pseudocode phase difference between the received signal and the locally copied pseudocode signal. d,k Indicates the residual carrier frequency in the received signal. n represents the carrier phase in the received signal. I and n Q These represent the noise terms for the I-path and Q-path respectively, A represents the amplitude after correlation calculation, R represents the correlation value, and T... coh Indicates the sampling period.

[0113] Optionally, after the correlation calculation, the signal integral energy value corresponding to each target positioning information can be determined based on each correlation result value. For example, the signal integral energy can be expressed as:

[0114]

[0115] It is understandable that, due to the autocorrelation between the received pseudo-code signal and the locally copied pseudo-code signal of the train receiver, the signal power or the integrated energy value is maximized when the locally copied signal perfectly matches or is identical to the received signal. By fitting the integrated energy values ​​of each discrete signal, the location X of the maximum integrated energy value is obtained. k At this moment, X k This provides the most accurate location information within the preset search range.

[0116] Based on the above derivation, the train receiver can obtain more accurate positioning information X. k This allows for more accurate prediction of the location of Doppler frequency shift mutations, which are then fed back to the tracking loop, reducing the impact of Doppler frequency shift mutations on the tracking loop.

[0117] The train positioning method provided by this invention performs correlation calculations on the received signal and the locally copied signal of the train receiver corresponding to each target positioning information to obtain multiple correlation result values. Then, based on each correlation result value, it determines the signal integral energy value corresponding to each target positioning information. This facilitates the accurate determination of the Doppler frequency shift change position based on the signal integral energy value corresponding to each target positioning information, which can reduce the impact of Doppler frequency shift changes on the tracking loop and improve the positioning accuracy of the tracking loop for the train.

[0118] Optionally, determining the train receiver's locally copied signal corresponding to each target positioning information includes:

[0119] Determine the distance between the train receiver and the target base station, wherein the target base station is the base station closest to the train receiver;

[0120] Based on the relationship between the carrier phase difference and the distance, the carrier phase difference corresponding to each target positioning information is determined;

[0121] Based on the carrier phase difference, the train receiver local copy signal corresponding to each target positioning information is determined.

[0122] Specifically, in this embodiment of the invention, after determining multiple target positioning information within a preset search range, the distance between the train receiver and the nearest target base station can be determined. Furthermore, based on the relationship between carrier phase difference and distance, the carrier phase difference corresponding to each target positioning information is determined. Then, based on each carrier phase difference, the train receiver local copy signal corresponding to each target positioning information is determined.

[0123] Understandably, in base station positioning, the location of a base station is usually a fixed coordinate. Therefore, the train receiver can obtain the location coordinates of each base station in advance through communication signals, and thus determine the target base station closest to the train receiver.

[0124] The train positioning method provided by this invention determines the carrier phase difference corresponding to each target positioning information based on the relationship between the carrier phase difference and the distance between the train receiver and the target base station. Then, based on each carrier phase difference, it determines the local copy signal of the train receiver corresponding to each target positioning information. This facilitates the subsequent determination of the signal integral energy value corresponding to each target positioning information based on the current received signal of the train receiver and the local copy signal of the train receiver corresponding to each target positioning information. Furthermore, based on the signal integral energy value corresponding to each target positioning information, it accurately determines the position of the Doppler frequency shift change, which can reduce the impact of the Doppler frequency shift change on the tracking loop and improve the positioning accuracy of the tracking loop for the train.

[0125] Optionally, the expression for the relationship between the carrier phase difference and the distance is:

[0126] φ=λ -1 r+N

[0127] Where φ represents the carrier phase difference, r represents the distance, λ represents the carrier wavelength, and N represents the periodic ambiguity.

[0128] Specifically, in this embodiment of the invention, the relationship between carrier phase difference and distance, expressed as φ = λ, can be used. -1 r+N determines the carrier phase difference corresponding to each target positioning information.

[0129] It is understandable that, at the k-th epoch, the location information feedback value can be used. Using the search center as the search area, a preset search range is divided according to a preset error search interval Δx to obtain multiple target location information, each target location information X i，k According to the relationship between carrier phase difference and distance, φ=λ -1 r+N generates the corresponding carrier phase difference, thereby generating the corresponding local replicated signal, which is then coherently integrated with the tracking loop input signal. By fitting the integrated energy values ​​corresponding to the positioning information of each target, the train receiver can obtain the positioning information X corresponding to the position with the maximum signal energy. k X k This refers to the location of Doppler frequency abrupt changes, which effectively improves the train receiver's prediction accuracy for the location of Doppler frequency abrupt changes. Figure 4 This is a schematic diagram of signal integral energy fitting provided by the present invention, as shown below. Figure 4 As shown, at the highest point of the fitted curve, which is the point of maximum signal energy, the corresponding position X is... k This refers to the location of the Doppler frequency abrupt change.

[0130] The train positioning method provided by this invention utilizes the relationship between carrier phase difference and distance, expressed as φ=λ. -1 The process involves r+N to determine the carrier phase difference corresponding to each target positioning information. Based on these carrier phase differences, the train receiver's locally copied signal for each target positioning information is determined. This facilitates the subsequent determination of the signal integral energy value corresponding to each target positioning information based on the train receiver's current received signal and the train receiver's locally copied signal for each target positioning information. Furthermore, the Doppler frequency shift abrupt change position can be accurately determined based on the signal integral energy value corresponding to each target positioning information. This reduces the impact of Doppler frequency shift abrupt changes on the tracking loop and improves the tracking loop's positioning accuracy for the train.

[0131] Figure 5 This is one of the structural schematic diagrams of the train positioning system provided by the present invention, such as... Figure 5 As shown, the train positioning results are first... The feedback is sent to the location information unitization module, which uses the location information feedback value. Centered on the target, the preset search range is divided according to the error search interval Δx to obtain multiple target positioning information, each target positioning information X i，k Based on the distance-related relationship φ=λ -1 r+N generates the corresponding carrier phase difference, thereby generating the corresponding receiver local copy signal. This signal is then coherently integrated with the tracking loop input signal, and the discrete integrated energy value is fitted to obtain the positioning information X corresponding to the location of the maximum signal energy.k This feedback is sent to the tracking loop, thereby reducing the impact of Doppler frequency shift abrupt changes on the tracking loop and improving the tracking loop's positioning accuracy for the train.

[0132] It is understood that the main body executing the train positioning method provided in this embodiment of the invention can be an adaptive tracking loop based on positioning information feedback and local error search, which can effectively reduce the impact of Doppler frequency shift abrupt changes on train positioning accuracy.

[0133] Figure 6 This is the second structural schematic diagram of the train positioning system provided by the present invention, as shown below. Figure 6 As shown, the train receiver inputs the signals processed by the RF front-end (tracking loop input signal and train receiver locally replicated signal) into the tracking loop. The tracking loop input signal and the receiver's locally replicated signal are coherently integrated to obtain a coherent integral value. This coherent integral value is then input to the discriminator to obtain the carrier frequency difference and carrier phase difference between the input signal and the locally replicated signal. The carrier frequency difference and carrier phase difference are processed by a second-order FLL (Frequency Locked Loop) assisted by a third-order PLL (Phase Locked Loop) loop filter, and the output is sent to the voltage-controlled oscillator to adjust the carrier frequency and carrier phase of the locally replicated signal. When the discriminator output approaches 0, the carrier frequency and carrier phase of the locally replicated signal are nearly identical to the input signal, which is the precise output value of the tracking loop.

[0134] The train positioning method provided by this invention uses the train's positioning information feedback value as the search center to perform local error search within a preset search range. Based on the signal integral energy values ​​corresponding to multiple target positioning information within the preset search range, the location of Doppler frequency shift abrupt changes can be accurately determined, thereby reducing the impact of Doppler frequency shift abrupt changes on the tracking loop and improving the positioning accuracy of the tracking loop for the train.

[0135] The train positioning device provided by the present invention is described below. The train positioning device described below and the train positioning method described above can be referred to in correspondence.

[0136] Figure 7 This is a schematic diagram of the train positioning device provided by the present invention, as shown below. Figure 7 As shown, the device includes: a first determining module 710, a second determining module 720, a third determining module 730, and a fourth determining module 740; wherein:

[0137] The first determining module 710 is used to determine the positioning information of multiple targets within a preset search range based on a preset error search interval and with the train's positioning information feedback value as the search center.

[0138] The second determining module 720 is used to determine the signal integral energy value corresponding to each target positioning information;

[0139] The third determining module 730 is used to determine the location of the Doppler frequency shift abrupt change based on the signal integral energy value corresponding to each target positioning information;

[0140] The fourth determining module 740 is used to adjust the tracking loop based on the position of the Doppler frequency shift abrupt change, and to determine the position information of the train through the adjusted tracking loop.

[0141] The train positioning device provided by the present invention performs local error search within a preset search range by using the train's positioning information feedback value as the search center. Based on the signal integral energy values ​​corresponding to multiple target positioning information within the preset search range, the location of Doppler frequency shift abrupt changes can be accurately determined, thereby reducing the impact of Doppler frequency shift abrupt changes on the tracking loop and improving the positioning accuracy of the tracking loop for the train.

[0142] It should be noted that the train positioning device provided in this embodiment of the invention can implement all the method steps implemented in the above-mentioned train positioning method embodiment and can achieve the same technical effect. Here, the parts that are the same as those in the method embodiment and the beneficial effects will not be described in detail.

[0143] Figure 8 This is a schematic diagram of the physical structure of the electronic device provided by the present invention, such as... Figure 8 As shown, the electronic device may include: a processor 810, a communication interface 820, a memory 830, and a communication bus 840, wherein the processor 810, the communication interface 820, and the memory 830 communicate with each other through the communication bus 840. The processor 810 can call logical instructions in the memory 830 to execute the train positioning method provided by the above methods, which includes:

[0144] Based on a preset error search interval, the positioning information of multiple targets within a preset search range is determined using the train's positioning information feedback value as the search center.

[0145] Determine the signal integral energy value corresponding to each target positioning information;

[0146] Based on the signal integral energy value corresponding to each target positioning information, the location of the Doppler frequency shift abrupt change is determined;

[0147] The tracking loop is adjusted based on the location of the Doppler frequency shift abrupt change, and the train's position information is determined through the adjusted tracking loop.

[0148] Furthermore, the logical instructions in the aforementioned memory 830 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, essentially, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0149] On the other hand, the present invention also provides a computer program product, the computer program product comprising a computer program stored on a non-transitory computer-readable storage medium, the computer program comprising program instructions, wherein when the program instructions are executed by a computer, the computer is able to execute the train positioning method provided by the above methods, the method comprising:

[0150] Based on a preset error search interval, the positioning information of multiple targets within a preset search range is determined using the train's positioning information feedback value as the search center.

[0151] Determine the signal integral energy value corresponding to each target positioning information;

[0152] Based on the signal integral energy value corresponding to each target positioning information, the location of the Doppler frequency shift abrupt change is determined;

[0153] The tracking loop is adjusted based on the location of the Doppler frequency shift abrupt change, and the train's position information is determined through the adjusted tracking loop.

[0154] In another aspect, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to perform the train positioning methods provided above, the method comprising:

[0155] Based on a preset error search interval, the positioning information of multiple targets within a preset search range is determined using the train's positioning information feedback value as the search center.

[0156] Determine the signal integral energy value corresponding to each target positioning information;

[0157] Based on the signal integral energy value corresponding to each target positioning information, the location of the Doppler frequency shift abrupt change is determined;

[0158] The tracking loop is adjusted based on the location of the Doppler frequency shift abrupt change, and the train's position information is determined through the adjusted tracking loop.

[0159] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0160] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0161] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A train positioning method characterized by, The method comprises the following steps: determining a plurality of target positioning information within a preset search range based on a preset error search interval and taking a positioning information feedback value of the train as a search center; determining a signal integration energy value corresponding to each target positioning information respectively; determining a Doppler frequency shift mutation position based on the signal integration energy value corresponding to each target positioning information respectively; adjusting a tracking loop based on the Doppler frequency shift mutation position, and determining the position information of the train through the adjusted tracking loop; The method comprises the following steps: determining a train receiver local copy signal corresponding to each target positioning information respectively; determining a signal integration energy value corresponding to each target positioning information respectively based on the current received signal of the train receiver and the train receiver local copy signal corresponding to each target positioning information respectively; The method comprises the following steps: determining the distance between the train receiver and a target base station, the target base station being the closest base station to the train receiver; determining a carrier phase difference corresponding to each target positioning information respectively based on the relationship between the carrier phase difference and the distance; determining a train receiver local copy signal corresponding to each target positioning information respectively based on the carrier phase difference respectively.

2. The train positioning method according to claim 1, characterized by, The method comprises the following steps: fitting the signal integration energy value corresponding to each target positioning information respectively to determine a maximum signal integration energy value; determining the position corresponding to the maximum signal integration energy value as the Doppler frequency shift mutation position.

3. The train positioning method according to claim 1, characterized by, The method comprises the following steps: performing correlation operation on the received signal and the train receiver local copy signal corresponding to each target positioning information respectively to obtain a plurality of correlation result values, the plurality of correlation result values corresponding to the plurality of target positioning information one by one; determining a signal integration energy value corresponding to each target positioning information respectively based on each correlation result value respectively.

4. The train positioning method according to claim 1, characterized by, The expression of the relationship between the carrier phase difference and the distance is as follows: φ = λ -1 r+N wherein φ represents the carrier phase difference, r represents the distance, λ represents the carrier wavelength, and N represents the integer ambiguity.

5. A train positioning apparatus, characterized by, The method comprises the following steps: a first determining module, configured to determine a plurality of target positioning information within a preset search range based on a preset error search interval and taking a positioning information feedback value of the train as a search center; a second determining module, configured to determine a signal integration energy value corresponding to each target positioning information respectively; a third determining module, configured to determine a Doppler frequency shift mutation position based on the signal integration energy value corresponding to each target positioning information respectively; a fourth determining module, configured to adjust a tracking loop based on the Doppler frequency shift mutation position, and determine the position information of the train through the adjusted tracking loop; The second determining module is specifically configured to: determining a train receiver local copy signal corresponding to each target positioning information respectively; determining a signal integration energy value corresponding to each target positioning information respectively based on a current receiving signal of the train receiver and the train receiver local copy signal corresponding to each target positioning information respectively; the second determining module is specifically further used for: determining a distance between the train receiver and a target base station, the target base station being a base station closest to the train receiver; determining a carrier phase difference corresponding to each target positioning information respectively based on a relationship between the carrier phase difference and the distance; determining a train receiver local copy signal corresponding to each target positioning information respectively based on the carrier phase difference respectively.

6. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the program to implement the train positioning method according to any one of claims 1 to 4.

7. A non-transitory computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the train positioning method according to any one of claims 1 to 4.

8. A computer program product comprising a computer program, characterized in that, The computer program is executed by the processor to implement the train positioning method according to any one of claims 1 to 4.

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