LFM signal ranging error correction method, device, equipment, medium and program product

Abstract

The present application relates to the technical field of radar ranging, and provides an LFM signal ranging error correction method, device, equipment, medium and program product, the method comprising: measuring target apparent distance and apparent speed; based on target apparent distance and apparent speed, solving target speed ambiguity to obtain target real speed; using the target real speed, estimating target distance offset; using the target distance offset, correcting target apparent distance; using the corrected target apparent distance, solving target distance ambiguity to obtain target real distance. The present application combines radar CFAR with speed ambiguity and distance ambiguity solving, realizes target speed estimation and distance correction, does not need to perform additional data processing on the sampled intermediate frequency signal, does not use additional detection waveform, and is suitable for multiple high-speed moving targets.

Description

Technical Field

[0001] This invention relates to the field of radar ranging technology, and more specifically, to a method, apparatus, equipment, medium, and program product for correcting ranging errors of LFM signals. Background Technology

[0002] Due to the range-Doppler coupling characteristics, linear frequency modulation (LFM) signals experience a range shift proportional to the Doppler frequency during pulse compression, leading to ranging errors. The higher the target speed, the greater the ranging error, necessitating error correction to improve target ranging accuracy.

[0003] Existing methods for correcting range-Doppler coupling errors include: positive and negative frequency modulation (PFMC) methods, track filtering for velocity estimation, and velocity ambiguity resolution methods. The PFMC method uses two different frequency modulation waveforms to detect targets, which reduces the radar's effective data rate by half, limiting its engineering applications. The track filtering method estimates target velocity based on the range difference after track filtering; however, ranging errors themselves affect the accuracy of track filtering, and the data interval for track filtering is only a few hundred milliseconds, leading to significant filtering errors due to high-speed target maneuvers. The velocity ambiguity resolution method uses waterfall plots to solve target velocity ambiguity, requiring segmented spectrum calculations of the intermediate frequency data, resulting in a large computational load and unsuitability for multiple targets.

[0004] Furthermore, correcting for range errors caused by different Doppler frequencies when dealing with multiple high-speed moving targets faces the following challenges: Doppler frequency estimation requires multi-target matching, and phase correction before pulse compression is not suitable for multiple targets. Currently, no relevant literature or patents have been found to provide solutions to these problems. Summary of the Invention

[0005] The present invention aims to provide a method, apparatus, device, medium and program product for correcting ranging errors of LFM signals, so as to solve the ranging error problem when radar LFM signals detect multiple high-speed moving targets.

[0006] In a first aspect, the present invention provides an LFM signal ranging error correction method, comprising:

[0007] Measure the apparent distance and apparent velocity of the target;

[0008] The target velocity ambiguity is resolved based on the target's apparent range and apparent velocity to obtain the target's true velocity;

[0009] Estimate the target distance offset using the target's true velocity;

[0010] The apparent distance of the target is corrected using the target distance offset;

[0011] By using the corrected apparent target distance, the target distance ambiguity is resolved, and the true target distance is obtained.

[0012] In some embodiments, measuring the apparent distance and apparent velocity of the target includes:

[0013] M groups of LFM signals with different repetition frequencies are emitted to detect moving targets. The target echoes corresponding to each group of repetition frequencies are processed, and the processed original point traces are condensed in the range and velocity dimensions to obtain the apparent range and apparent velocity. The target echo processing includes pulse compression, inter-pulse coherence, and constant false alarm rate detection.

[0014] In some embodiments, the step of resolving target velocity blur based on apparent target range and apparent velocity includes:

[0015] Select N groups from M repetition frequencies for multi-target matching and deblurring; sequentially select one target data point from the N repetition frequencies and use the least squares method to solve the target velocity ambiguity; based on the apparent velocity V of the j-th target in the i-th repetition frequency group... ij And apparent distance R ij Calculate the apparent velocity V ij The corresponding total possible speeds are represented as:

[0016]

[0017] Among them, V max V is the maximum detection speed of the radar. i,u =1 / PRI i ·λ2 is the repetition frequency PRI of the i-th group i The corresponding unambiguous velocity, where λ is the radar signal wavelength. Indicates rounding up;

[0018] After calculating all possible velocities from the selected data in the N sets of repetition frequencies, the resulting values ​​are arranged in ascending order to obtain a one-dimensional array V. o Calculate the one-dimensional array V o The root mean square deviation C of N adjacent elements V (j):

[0019]

[0020] in, For a one-dimensional array V o The mean of N consecutive values ​​in a given set;

[0021] If the minimum mean square deviation C V,min Less than the set first threshold T V If the target velocities at different repetition frequencies are matched successfully, the mean value is the true velocity of the target.

[0022] If the minimum mean square deviation C V,min Greater than the set first threshold T V If the target is not matched, the next data point is selected and the least squares method is used to solve the target velocity ambiguity.

[0023] In some embodiments, estimating the target distance offset using the target's true velocity includes:

[0024] Using the target's true speed Estimate the target Doppler frequency shift f d , is represented as:

[0025]

[0026] Using the estimated target Doppler frequency shift, the target range offset Δr is estimated, expressed as:

[0027] Δr=f d / κ·c / 2

[0028] Where κ=B / τ represents the frequency modulation slope of the LFM signal, B is the signal bandwidth, and τ is the signal pulse width.

[0029] In some embodiments, the target distance offset is used to correct the apparent target distance, including:

[0030] Subtracting the target range offset from the apparent target range yields the corrected apparent target range; where, for the j-th target apparent range R in the i-th repetition frequency group... ij The corrected target appears to be at distance R. ij,c Represented as: R ij,c =R ij -Δr.

[0031] In some embodiments, resolving target distance ambiguity using the corrected apparent target distance includes:

[0032] The least squares method is used to perform fuzzy range resolution on the corrected apparent target range.

[0033] Calculate the corrected apparent target range R ij,c The corresponding total possible distances are:

[0034]

[0035] Among them, R max R is the maximum detection range of the radar. i,u =PRI i ·c / 2 represents the repetition frequency PRI of the i-th group. i The corresponding unambiguous distance, This indicates rounding up, where c is the speed of light;

[0036] After calculating all possible distances for the successfully matched velocity data in N sets of repetition frequencies, the resulting values ​​are arranged in ascending order to obtain a one-dimensional array R. o Calculate the one-dimensional array R o The root mean square deviation C of N adjacent elements R (j):

[0037]

[0038] in, Given a one-dimensional array R o The mean of N consecutive values ​​in a given set;

[0039] If the minimum mean square deviation C R,min Less than the set second threshold T R If the target distances at different repetition frequencies are matched successfully, the mean value is considered to be the true distance of the target.

[0040] If the minimum mean square deviation C R,min Greater than the set second threshold T R If the target distance matching fails, the target velocity fuzziness and target distance fuzziness are recalculated.

[0041] Secondly, the present invention provides an LFM signal ranging error correction device, comprising:

[0042] The first processing unit is used to measure the apparent distance and apparent velocity of the target;

[0043] The second processing unit is used to resolve the target velocity ambiguity based on the target's apparent distance and apparent velocity to obtain the target's true velocity.

[0044] The third processing unit is used to estimate the target distance offset using the target's true velocity;

[0045] The fourth processing unit is used to correct the apparent target distance using the target distance offset;

[0046] The fifth processing unit is used to solve the target distance ambiguity using the corrected target apparent distance to obtain the target's true distance.

[0047] Thirdly, the present invention provides an electronic device, comprising:

[0048] At least one processor; and a memory communicatively connected to said at least one processor;

[0049] The memory stores instructions that can be executed by the at least one processor, and the at least one processor executes the instructions stored in the memory to perform the method described above.

[0050] Fourthly, the present invention provides a computer-readable storage medium for storing instructions that, when executed, cause the above-described method to be implemented.

[0051] Fifthly, the present invention provides a computer program product that, when invoked by a computer, causes the computer to execute the above-described method.

[0052] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0053] This invention addresses the ranging error problem when using radar LFM signals to detect multiple high-speed moving targets, proposing a ranging error correction method for LFM signals. This method first measures the apparent range and apparent velocity after CFAR (Conveyance-Based Arrangement). Then, it uses the least squares method to solve for the unambiguous target's true velocity. Based on the true velocity, it estimates the target range offset, corrects the apparent range using the range offset, and finally resolves the target range ambiguity to obtain the true target range and true target velocity. This method combines radar CFAR with velocity and range ambiguity resolution to achieve target velocity estimation and range correction. It eliminates the need for additional data processing on the sampled intermediate frequency signal and does not employ additional detection waveforms, and is applicable to multiple high-speed moving targets. Implementation examples show that the greater the relative speed between the target and the radar, the greater the ranging error of traditional measurement methods. Using the range correction method proposed in this invention, the ranging error remains within the measurement accuracy range of the radar system. Attached Figure Description

[0054] Figure 1 This is a flowchart of an LFM signal ranging error correction method proposed in an embodiment of the present invention.

[0055] Figure 2a This is a diagram showing the CFAR detection results corresponding to the first set of repetition frequencies in an example of an embodiment of the present invention.

[0056] Figure 2b This is a diagram showing the CFAR detection results corresponding to the first set of repetition frequencies in an example of an embodiment of the present invention.

[0057] Figure 2c This is a diagram showing the CFAR detection results corresponding to the first set of repetition frequencies in an example of an embodiment of the present invention.

[0058] Figure 2d This is a diagram showing the CFAR detection results corresponding to the first set of repetition frequencies in an example of an embodiment of the present invention.

[0059] Figure 3 A diagram showing the target distances measured using different methods.

[0060] Figure 4 This is a schematic diagram of the structure of an LFM signal ranging error correction device proposed in an embodiment of the present invention.

[0061] Figure 5 This is a schematic diagram of the structure of an electronic device proposed in an embodiment of the present invention. Detailed Implementation

[0062] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0063] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0064] like Figure 1 As shown in the figure, this embodiment proposes an LFM signal ranging error correction method, which includes the following steps:

[0065] Step S1: Measure the apparent distance and apparent velocity of the target.

[0066] In some embodiments, step S1 includes: transmitting M groups of LFM signals with different repetition frequencies to detect moving targets; processing the target echoes corresponding to each group of repetition frequencies; and converging the processed original point traces in the range and velocity dimensions to obtain apparent range and apparent velocity. The processing of the target echoes includes pulse compression, inter-pulse coherence, and constant false alarm rate (CFAR) detection.

[0067] Step S2: Solve the target velocity ambiguity based on the target's apparent distance and apparent velocity to obtain the target's true velocity.

[0068] From the M groups of repetition frequencies, N groups are selected for multi-target matching and deambiguation. There are a total of A combination. In some embodiments, step S2 includes the following sub-steps:

[0069] Step S21: Select one target data point from each group of repetition frequencies and use the least squares method to solve the target velocity ambiguity.

[0070] Step S22, based on the apparent velocity V of the j-th target in the i-th group of repetition frequencies. ijAnd apparent distance R ij Calculate the apparent velocity V ij The corresponding total possible speeds are represented as:

[0071]

[0072] Among them, V max V is the maximum detection speed of the radar. i,u =1 / PRI i ·λ / 2 represents the repetition frequency PRI of the i-th group. i The corresponding unambiguous velocity, where λ is the radar signal wavelength. This indicates rounding up to the nearest integer.

[0073] Step S23: After calculating all possible velocities of the selected data in the N sets of repetition frequencies, arrange the obtained values ​​in ascending order to obtain a one-dimensional array V. o Calculate the one-dimensional array V o The root mean square deviation C of N adjacent elements V (j):

[0074]

[0075] in, For a one-dimensional array V o The mean of N adjacent values ​​in a given set.

[0076] Step S24, calculate the minimum standard deviation C. V,min :

[0077] If the minimum mean square deviation C V,min Less than the set first threshold T V If the target velocities at different repetition frequencies are considered to be successfully matched, the corresponding mean values ​​are... That is, the target's true speed;

[0078] If the minimum mean square deviation C V,min Greater than the set first threshold T V If the target match is unsuccessful, select the next data and repeat steps S21 to S24.

[0079] Step S3: Estimate the target distance offset using the target's true velocity.

[0080] Step S31, using the target's true speed Estimate the target Doppler frequency shift f d , is represented as:

[0081]

[0082] Step S32: Using the estimated target Doppler frequency shift, estimate the target range offset, expressed as:

[0083] Δr=f d / κ·c / 2 (4)

[0084] Where κ=B / τ represents the frequency modulation slope of the LFM signal, B is the signal bandwidth, and τ is the signal pulse width. Therefore, the target range offset can be calculated as:

[0085]

[0086] Step S4: Correct the apparent distance of the target using the target distance offset.

[0087] For the target data after successful velocity matching, the apparent range R of the j-th target in the i-th group of repetition frequencies is corrected using equation (5). ij The corrected target appears to be at distance R. ij,c Represented as:

[0088] R ij,c =R ij -Δr (6)

[0089] Step S5: Using the corrected apparent target distance, solve the target distance ambiguity to obtain the true target distance.

[0090] In some embodiments, step S5 includes the following sub-steps:

[0091] Step S51: Use the least squares method to perform range fuzzy resolution on the corrected target apparent range, and calculate the corrected target apparent range R. ij,c The corresponding total possible distances are:

[0092]

[0093] Among them, R max R is the maximum detection range of the radar. i,u =PRI i ·c / 2 represents the repetition frequency PRI of the i-th group. i The corresponding unambiguous distance, This indicates rounding up, where c is the speed of light.

[0094] Step S52: After calculating all possible distances for the successfully matched velocity data in the N sets of repetition frequencies, arrange the obtained values ​​in ascending order to obtain a one-dimensional array R. o Calculate the one-dimensional array R o The root mean square deviation C of N adjacent elements R (j):

[0095]

[0096] in, Given a one-dimensional array R o The mean of N adjacent values ​​in a given set.

[0097] Step S53, calculate the minimum standard deviation C. R,min :

[0098] If the minimum mean square deviation C R,min Less than the set second threshold T R If the target distance matching is successful at different repetition frequencies, the corresponding mean value is considered to be... This is the true distance to the target; output the true distance to the target. and the target's true speed

[0099] If the minimum mean square deviation C R,min Greater than the set second threshold T R If the target distance matching fails, then the steps S2 to S5 are repeated.

[0100] To verify the performance of the proposed correction method, four moving targets were simulated using radar signal processing. The distances between the four targets and the radar were assumed to be 100km, 101km, 102km, and 103km, respectively, with relative speeds of 1000m / s, -500m / s, 800m / s, and -300m / s, respectively. The radar signal wavelength was 0.01m, pulse width 20µs, and bandwidth 2MHz.

[0101] according to Figure 1 The implementation process is shown below. The steps for this example are as follows:

[0102] Step S1: Measure the apparent distance and apparent velocity of the target.

[0103] Four sets of LFM signals with different repetition frequencies were emitted to detect moving targets, with pulse repetition intervals (PRI) of 211 μs, 229 μs, 241 μs, and 257 μs, respectively. The target echoes corresponding to each PRI were processed using pulse compression, inter-pulse coherence, and constant false alarm rate (CFAR) detection. The processed raw point traces were then converged in the range and velocity dimensions to obtain the apparent range and apparent velocity. The CFAR detection results for the four PRI sets are shown below. Figure 2a , Figure 2b , Figure 2c , Figure 2d As shown, there are only 3 targets in the second group of repetition frequencies because one of the targets is in the radar blind zone. The apparent range and apparent Doppler frequency (apparent velocity × wavelength / 2) after condensation are shown in Table 1.

[0104] Table 1. Apparent distance and apparent Doppler frequency after condensation:

[0105]

[0106] Step S2: Solve the target velocity ambiguity based on the target's apparent distance and apparent velocity to obtain the target's true velocity.

[0107] Three PRI groups are selected from four repetition frequencies for deambiguation, resulting in four possible combinations. One data point from each PRI group is selected to solve the velocity ambiguity using the least squares method. When the minimum mean square error is less than the radar system's velocity measurement accuracy, the target velocity is considered to be successfully matched, and the obtained true target velocity is 999.996 m / s.

[0108] Step S3: Estimate the target distance offset using the target's true velocity.

[0109] Based on the calculated true target velocity, the estimated Doppler frequency shift of the target is 200kHz, and the target distance deviation caused by the Doppler frequency shift is 299.999m.

[0110] Step S4: Correct the apparent distance of the target using the target distance offset.

[0111] For target data after successful velocity matching, the apparent distance is corrected using the estimated target distance deviation.

[0112] Step S5: Using the corrected apparent target distance, solve the target distance ambiguity to obtain the true target distance.

[0113] For target data that has been successfully matched in velocity and corrected for apparent distance, the least squares method is used to resolve target distance ambiguity. When the minimum mean square error is less than the ranging accuracy of the radar system, the target distance is considered to have been successfully matched, and the true distance of the target is output as 99997m.

[0114] After traversing all target data combinations and repetition frequency combinations, the measured distances of the four targets were obtained as 99997m, 100988m, 101981m, and 102995m, respectively.

[0115] To evaluate the ranging performance of this method, 50 Monte Carlo tests were conducted. In each test, the ranging and velocity errors inherent in the radar system were randomly generated, reflected in the apparent range and apparent velocity of the test data. The distance measurement results of conventional methods and the method described in this patent are as follows: Figure 3 As shown, the ranging error of the method of the present invention is much smaller than that of the traditional method, which is within the measurement accuracy range of the radar system.

[0116] Based on the same technological concept, such as Figure 4As shown, this embodiment of the invention also provides an LFM signal ranging error correction device, characterized in that it includes...

[0117] The first processing unit is used to measure the apparent distance and apparent velocity of the target;

[0118] The second processing unit is used to resolve the target velocity ambiguity based on the target's apparent distance and apparent velocity to obtain the target's true velocity.

[0119] The third processing unit is used to estimate the target distance offset using the target's true velocity;

[0120] The fourth processing unit is used to correct the apparent target distance using the target distance offset;

[0121] The fifth processing unit is used to solve the target distance ambiguity using the corrected target apparent distance to obtain the target's true distance.

[0122] As for the specific processing methods of each processing unit in the above-mentioned device, please refer to the detailed description of the above method, which will not be repeated here.

[0123] Based on the same technical concept, embodiments of the present invention also provide a radar target simulation system, wherein the radar target simulation system is equipped with the aforementioned high-resolution range image echo simulation device. The working principle of the high-resolution range image echo simulation device can be referred to the specific description of the above method, and will not be repeated here.

[0124] Based on the same technical concept, embodiments of the present invention also provide an electronic device that can implement the LFM signal ranging error correction method provided in the above embodiments of the present invention. In one embodiment, the electronic device can be a server, a terminal device, or other electronic devices. Figure 5 As shown, the electronic device may include:

[0125] At least one processor and a memory connected to the at least one processor. In this embodiment of the invention, the specific connection medium between the processor and the memory is not limited. Figure 5 The example used is the connection between the processor and memory via a bus. The bus... Figure 5 The connections between other components are indicated by thick lines and are for illustrative purposes only, not as limiting information. Buses can be divided into address buses, data buses, control buses, etc., but for ease of representation, [the specific bus type is not shown here]. Figure 5 The processor is represented by a single thick line, but this does not imply that there is only one bus or one type of bus. Alternatively, a processor can also be called a controller; there are no restrictions on the name.

[0126] In this embodiment of the invention, the memory stores instructions executable by at least one processor. By executing the instructions stored in the memory, the at least one processor can perform the LFM signal ranging error correction method described above. The processor can implement... Figure 5 The functions of each module in the device shown.

[0127] The processor is the control center of the device. It can connect to various parts of the control device through various interfaces and lines. By running or executing instructions stored in memory and calling data stored in memory, it can monitor the device's various functions and process data, thereby enabling overall monitoring of the device.

[0128] In an alternative design, the processor may include one or more processing units. The processor may integrate an application processor and a modem processor, wherein the application processor primarily handles the operating system, user interface, and applications, while the modem processor primarily handles wireless communication. It is understood that the modem processor may also not be integrated into the processor. In some embodiments, the processor and memory may be implemented on the same chip; in some embodiments, they may also be implemented separately on separate chips.

[0129] The processor can be a general-purpose processor, such as a CPU, digital signal processor, application-specific integrated circuit, field-programmable gate array or other programmable logic device, discrete gate or transistor logic device, or discrete hardware component, capable of implementing or executing the methods, steps, and logic block diagrams disclosed in the embodiments of this invention. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the LFM signal ranging error correction method disclosed in the embodiments of this invention can be directly manifested as being executed by a hardware processor, or executed by a combination of hardware and software modules within the processor.

[0130] Memory, as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs, non-volatile computer-executable programs, and modules. Memory can include at least one type of storage medium, such as flash memory, hard disk, multimedia card, card-type memory, random access memory (RAM), static random access memory (SRAM), programmable read-only memory (PROM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), magnetic memory, magnetic disk, optical disk, etc. Memory is any other medium capable of carrying or storing desired program code in the form of instructions or data structures, and accessible by a computer, but is not limited thereto. In embodiments of the present invention, memory can also be a circuit or any other device capable of implementing storage functions, used to store program instructions and / or data.

[0131] By designing and programming the processor, the code corresponding to the LFM signal ranging error correction method described in the foregoing embodiments can be embedded into the chip, enabling the chip to execute the steps of the method described in the foregoing embodiments during operation. How to design and program the processor is a technique well-known to those skilled in the art and will not be elaborated upon here.

[0132] Based on the same inventive concept, embodiments of the present invention also provide a storage medium storing computer instructions that, when executed on a computer, cause the computer to perform an LFM signal ranging error correction method described above.

[0133] In some alternative embodiments, the present invention also provides that various aspects of the LFM signal ranging error correction method can also be implemented in the form of a program product, which includes program code that, when the program product is run on a device, causes the control device to perform the steps in the LFM signal ranging error correction method according to various exemplary embodiments of the present invention described above.

[0134] It should be noted that although several units or sub-units of the apparatus have been mentioned in the detailed description above, this division is merely exemplary and not mandatory. In fact, according to embodiments of the invention, the features and functions of two or more units described above can be embodied in one unit. Conversely, the features and functions of one unit described above can be further divided and embodied by multiple units. Furthermore, although the operation of the method of the invention is described in a specific order in the drawings, this does not require or imply that these operations must be performed in that specific order, or that all the operations shown must be performed to achieve the desired result. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

[0135] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0136] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a server, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0137] Program code for performing the operations of this invention can be written using any combination of one or more programming languages, including object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computing device, partially on the user's device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0138] In cases involving remote computing devices, the remote computing device can be connected to the user's computing device via any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computing device (e.g., via the Internet using an Internet service provider).

[0139] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0140] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0141] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for correcting LFM signal ranging errors, characterized in that, include: Measure the apparent distance and apparent velocity of the target; The target velocity ambiguity is resolved based on the target's apparent range and apparent velocity to obtain the target's true velocity; Estimate the target distance offset using the target's true velocity; The apparent distance of the target is corrected using the target distance offset; By using the corrected apparent target distance, the target distance ambiguity is resolved, and the true target distance is obtained. The measurement of the apparent distance and apparent velocity of the target includes: M groups of LFM signals with different repetition frequencies are emitted to detect moving targets. The target echoes corresponding to each group of repetition frequencies are processed, and the raw point traces after processing are condensed in the range and velocity dimensions to obtain the apparent range and apparent velocity. The target echo processing includes pulse compression, inter-pulse coherence, and constant false alarm rate detection. The method for resolving target velocity ambiguity based on apparent target range and apparent velocity includes: From the M groups of repetition frequencies, N groups are selected for multi-target matching and deblurring; from the N groups of repetition frequencies, one target data point is selected sequentially, and the target velocity ambiguity is solved using the least squares method; based on the... i The first in the group repetition frequency j Apparent velocity of a target and visual distance Calculate apparent velocity The corresponding total possible speeds are represented as: in, This is the maximum detection speed of the radar. For the first i Group repetition frequency The corresponding unambiguous speed, For radar signal wavelength, Indicates rounding up; After calculating all possible velocities from the selected data in the N sets of repetition frequencies, the resulting values ​​are arranged in ascending order to obtain a one-dimensional array. Calculate the one-dimensional array Mean square error of N adjacent elements : in, A one-dimensional array The mean of N consecutive values ​​in a given set; If the minimum mean square error Less than the set first threshold If the target velocities at different repetition frequencies are matched successfully, the mean value is the true velocity of the target. If the minimum mean square error Greater than the set first threshold If the target is not matched, the next data point is selected and the least squares method is used to solve the target velocity ambiguity.

2. The LFM signal ranging error correction method according to claim 1, characterized in that, Using the target's true velocity, the target distance offset is estimated, including: Using the target's true speed Estimate the target Doppler frequency shift , is represented as: The target range offset is estimated using the estimated target Doppler frequency shift. , is represented as: in, This indicates the frequency modulation slope of the LFM signal. For signal bandwidth, This refers to the signal pulse width.

3. The LFM signal ranging error correction method according to claim 2, characterized in that, Correcting the apparent target distance using the target distance offset includes: Subtract the target distance offset from the target apparent distance to obtain the corrected target apparent distance; where, for the th i The first in the group repetition frequency j The target appears to be at a distance. The corrected target apparent distance Represented as: .

4. The LFM signal ranging error correction method according to claim 3, characterized in that, Using the corrected apparent target range, target range ambiguity is resolved, including: The least squares method is used to perform fuzzy range resolution on the corrected apparent target range. Calculate the corrected target apparent distance The corresponding total possible distances are: in, This is the maximum detection range of the radar. For the i-th group of repetition frequencies The corresponding unambiguous distance, Indicates rounding up. The speed of light; After calculating all possible distances for the successfully matched velocity data in N sets of repetition frequencies, the resulting values ​​are arranged in ascending order to obtain a one-dimensional array. Calculate the one-dimensional array Mean square error of N adjacent elements : in, A one-dimensional array The mean of N consecutive values ​​in a given set; If the minimum mean square error Less than the set second threshold If the target distances at different repetition frequencies are matched successfully, the mean value is considered to be the true distance of the target. If the minimum mean square error Greater than the set second threshold If the target distance matching fails, the target velocity fuzziness and target distance fuzziness are recalculated.

5. An LFM signal ranging error correction device, characterized in that, For performing the method as described in any one of claims 1-4, the LFM signal ranging error correction device comprises: The first processing unit is used to measure the apparent distance and apparent velocity of the target; The second processing unit is used to resolve the target velocity ambiguity based on the target's apparent distance and apparent velocity to obtain the target's true velocity. The third processing unit is used to estimate the target distance offset using the target's true velocity; The fourth processing unit is used to correct the apparent target distance using the target distance offset; The fifth processing unit is used to solve the target distance ambiguity using the corrected target apparent distance to obtain the target's true distance.

6. An electronic device, characterized in that, include: At least one processor; and a memory communicatively connected to the at least one processor; The memory stores instructions executable by the at least one processor, which executes the instructions stored in the memory to perform the method as described in any one of claims 1-4.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium is used to store instructions that, when executed, cause the method as described in any one of claims 1-4 to be implemented.

8. A computer program product, characterized in that, When the computer program product is invoked by a computer, it causes the computer to perform the method as described in any one of claims 1-4.

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