A method and device for suppressing environmental background interference in the frequency domain of a radar, and a medium

Abstract

The application discloses a kind of radar's environment background interference frequency domain suppression method, device and medium, wherein method includes: based on radar signal, twice measurement with preset target and no target is carried out, according to twice measurement result, set a reference threshold value;Set a storage space for storing no target measurement result, shift register and dynamic average processing are carried out to no target measurement result, and Fourier transform is obtained environment data;Real-time acquisition of detection data and environment data are taken modulo in frequency domain and subtracted, the subtraction result and reference threshold value are compared, to judge whether there is target.The modeling of the environment information of the present application is more accurate, and after shift register and dynamic average processing, the environment background and its changes can be detected in real time.In addition, the present application does not need to be processed in time domain, which reduces the complexity and cost of system implementation.The present application can be widely applied in the field of digital signal processing.

Description

Technical Field

[0001] This invention relates to the field of digital signal processing technology, and in particular to a method, apparatus and medium for suppressing environmental background interference in the frequency domain of radar. Background Technology

[0002] In recent years, radar has been widely used in various measurements due to its low power consumption, low cost, high integration, and high stability, such as vehicle detection, pedestrian detection, and positioning. Whether indoors or outdoors, there is always an environmental background beyond the object being measured. This background can also be detected by radar, forming data clutter and interfering with radar detection performance. Especially in practical applications, the environmental background is very complex, and clutter interference is significant. To ensure detection performance, specialized background clutter suppression methods are needed to minimize clutter interference and improve the target detection rate, enabling the radar to obtain accurate information such as the speed, direction, and distance of the target.

[0003] Background clutter is characterized by its variability and complexity. On the one hand, to address its variability, current methods primarily employ "averaging" of background clutter. This involves acquiring radar echo data in the absence of a target, averaging it, and using the averaged data as background clutter modeling data. Algorithms are then used to eliminate background clutter. The drawback of this method is its inability to handle situations where the background environment may change randomly, such as wind blowing trees or rain hitting doors and windows. This leads to inaccurate background clutter modeling, a lack of real-time performance, and erroneous processing results. On the other hand, to address its complexity, current methods primarily employ "background time-domain subtraction." This method subtracts the data acquired in the presence of a target from the background environment modeling data in the time domain, resulting in data containing only the target information. This method requires time-domain alignment before subtraction; otherwise, the subtraction will produce distorted results. However, time-domain alignment is complex, resource-intensive, and increases design complexity. Summary of the Invention

[0004] In order to at least partially solve one of the technical problems existing in the prior art, the present invention aims to provide a method, device and medium for suppressing environmental background interference in the frequency domain of radar.

[0005] The technical solution adopted in this invention is:

[0006] A method for suppressing ambient background interference in the frequency domain of radar includes the following steps:

[0007] Based on radar signals, two measurements are performed: one with a preset target and one without. A reference threshold is then set based on the results of the two measurements.

[0008] Set up a storage space to store the targetless measurement results, perform shift registration and dynamic averaging on the targetless measurement results, and perform Fourier transform to obtain environmental data;

[0009] The real-time collected detection data and environmental data are moduloed in the frequency domain and subtracted. The subtraction result is compared with a reference threshold to determine whether a target exists.

[0010] If a target exists, calculate the distance between the target and the radar.

[0011] Furthermore, the step of performing two measurements based on radar signals—one with a preset target and one without—and setting a reference threshold based on the results of the two measurements includes:

[0012] In two scenarios, one with no target and one with a preset target, i-frame radar signals are transmitted and the echo signals are received. The transmitted signals and echo signals are mixed and sampled to obtain i-frame intermediate frequency data G in the scenario with no target and i-frame intermediate frequency data H in the scenario with a target.

[0013] In scenarios without a target, the lower limit of the frequency domain threshold is determined based on the intermediate frequency data G; in scenarios with a preset target, the upper limit of the frequency domain threshold is determined based on the intermediate frequency data H.

[0014] The reference threshold T is calculated based on the lower limit and upper limit of the frequency domain threshold.

[0015] Furthermore, determining the lower limit of the frequency domain threshold based on the intermediate frequency data G in the absence of a target scenario includes:

[0016] When no target is present in the environment, an i-frame signal is transmitted. After mixing and acquiring the transmitted and received signals, the intermediate frequency data G1, G2, ..., G of the i-frame are obtained. i ;

[0017] Then, respectively analyze the intermediate frequency data G1, G2, ..., G of the i-frame. i Perform a Fourier transform to obtain J1, J2, ..., J i The modulo subtraction of adjacent frames after Fourier transform yields L1, L2, ..., L... i-1 ;

[0018] From L1, L2, ..., L i-1 Select the maximum value from the given values, i.e., M1 = max(L1), M2 = max(L2), ... M i-1 =max(L i-1 After averaging, the lower limit of the frequency domain threshold is obtained as t1 = (M1 + M2 + ... + M...). i-1 ) / (i-1).

[0019] Furthermore, the modulo subtraction of adjacent frames after Fourier transform yields L1, L2, ..., L... i-1 ,include:

[0020] After the intermediate frequency data undergoes Fourier transform, J1, J2, ..., J are obtained. i Since the numbers are complex, the modulo subtraction of adjacent frame data yields L1 = abs(J2) - abs(J1), L2 = abs(J3) - abs(J2), ..., L... i-1 =abs(J i )-abs(J i-1 The modulus (abs) is the sum of the squares of the real and imaginary parts and then the square root.

[0021] Furthermore, the provision of a storage space for storing targetless measurement results, the shifting and dynamic averaging of the targetless measurement results, and the Fourier transform to obtain environmental data include:

[0022] Set up a storage space to store i-frame data, and store the intermediate frequency data G1, G2, ..., G of the i-frame after mixing and acquisition. i Stored in storage space, averaged to obtain F k = (G1+G2+…+G i ) / i, where the sampling frame number k=1, for F k The Fourier transform is performed to obtain its spectrum P, which is the environmental data.

[0023] Furthermore, the step of taking the modulus of the real-time collected detection data and the environmental data in the frequency domain and subtracting them, then comparing the subtraction result with a reference threshold to determine whether a target exists, includes:

[0024] Continuously transmit radar signal R1, receive echo signal R2, mix and sample signals R1 and R2 to obtain intermediate frequency data, and perform Fourier transform on the intermediate frequency data to obtain data Y;

[0025] Perform modulo operation on the environmental data P stored in the storage space and the obtained data Y;

[0026] Subtract the modulus of the environmental data P from the modulus of the obtained data Y to obtain the subtraction result X;

[0027] Based on the comparison between the subtraction result X and the reference threshold T, determine whether there is a target in the environment;

[0028] If the subtraction result X is greater than the reference threshold T, it indicates that a target exists; if the subtraction result X is less than the reference threshold T, it indicates that no target exists and only background data exists. The environmental data P in the storage space is updated based on this background data.

[0029] Furthermore, update the environmental data P in the storage space in the following way:

[0030] First, the initially acquired frame signal G... k (k=1) Delete, and then introduce the newly acquired frame signal G into the storage space. i+k Keep the total amount of data in the storage space constant;

[0031] The sampling frame number k is incremented by 1, i.e., k = k + 1. Then, the data in the storage space is averaged to obtain F. k =(G k +…+G i+k-1 ) / i;

[0032] Finally, regarding F k Perform a Fourier transform to obtain the spectrum P, which is the updated environmental data.

[0033] Furthermore, the signal transmitted in the radar signal is a frequency-modulated continuous signal;

[0034] The frequency of the frequency-modulated continuous signal increases linearly with time; a frequency-modulated continuous signal period is the duration of the signal from the start frequency to the cutoff frequency. A frame of frequency-modulated continuous signal period includes two frequency-modulated continuous signal periods and a frame idle time, starting from the first frequency-modulated continuous signal to the cutoff, followed by the second frequency-modulated continuous signal to the cutoff, and finally the frame idle time. A frame of frequency-modulated continuous signal period is at least greater than two frequency-modulated continuous signal periods.

[0035] Another technical solution adopted in this invention is:

[0036] A frequency domain suppression device for environmental background interference of radar, comprising:

[0037] At least one processor;

[0038] At least one memory for storing at least one program;

[0039] When the at least one program is executed by the at least one processor, the at least one processor implements the method described above.

[0040] Another technical solution adopted in this invention is:

[0041] A computer-readable storage medium storing a processor-executable program, which, when executed by a processor, performs the method described above.

[0042] The beneficial effects of this invention are: It provides more accurate environmental information modeling, and after shift register and dynamic averaging processing, it can detect the environmental background and its changes in real time. Furthermore, this invention eliminates the need for time-domain processing, avoiding the complex operation of time-domain alignment of received environmental echoes, reducing system implementation complexity and cost, and meeting the needs of radar detection, positioning, security, and monitoring applications. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following description is provided with accompanying drawings of the relevant technical solutions in the embodiments of the present invention or the prior art. It should be understood that the accompanying drawings described below are only for the purpose of clearly illustrating some embodiments of the technical solutions of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is a flowchart of a radar environmental background interference frequency domain suppression method according to an embodiment of the present invention;

[0045] Figure 2 This is a flowchart of setting a reference threshold in an embodiment of the present invention;

[0046] Figure 3 This is a flowchart illustrating the process of obtaining the initial environmental data in an embodiment of the present invention;

[0047] Figure 4 This is a flowchart of detecting targets in the environment in an embodiment of the present invention;

[0048] Figure 5 This is a flowchart illustrating the process of updating environmental data within the storage module in this embodiment of the invention.

[0049] Figure 6 This is a schematic diagram of the environmental background interference frequency domain suppression system of the radar of the present invention;

[0050] Figure 7 This is a schematic diagram illustrating the application of the radar's environmental background interference frequency domain suppression system in an embodiment of the present invention. Detailed Implementation

[0051] The embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. The step numbers in the following embodiments are set only for ease of explanation, and there is no limitation on the order between the steps. The execution order of each step in the embodiments can be adaptively adjusted according to the understanding of those skilled in the art.

[0052] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0053] In the description of this invention, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0054] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0055] like Figure 1 As shown, this embodiment provides a frequency domain suppression method for environmental background interference of radar, including the following steps:

[0056] S1. Based on radar signals, perform two measurements: one with a preset target and one without. Set a reference threshold based on the results of the two measurements.

[0057] Step S1 includes the following steps S11-S12:

[0058] S11. In two scenarios, one with no target and one with a preset target, i-frame radar signals are transmitted respectively. The radar signal waveform is a frequency-modulated continuous wave. Then, the echo signal is received. The transmitted signal and the echo signal are mixed and sampled to obtain i-frame intermediate frequency data G in the scenario without a target and i-frame intermediate frequency data H in the scenario with a target.

[0059] As a further optional implementation, the transmitted signal is a frequency-modulated continuous signal. The frequency of the frequency-modulated continuous signal increases linearly with time. One frequency-modulated continuous signal period is the duration of the signal from the start frequency to the cutoff frequency. One frame of frequency-modulated continuous signal period includes two frequency-modulated continuous signal periods and a frame idle time. It starts from the first frequency-modulated continuous signal and ends, followed by the second frequency-modulated continuous signal and ends, and finally the frame idle time. One frame of frequency-modulated continuous signal period is at least greater than two frequency-modulated continuous signal periods.

[0060] S12. In the absence of a target scenario, the lower limit of the frequency domain threshold is determined based on the intermediate frequency data G. In the presence of a preset target scenario, the upper limit of the frequency domain threshold is determined based on the intermediate frequency data H. The reference threshold T is then calculated by averaging the upper and lower limit frequency domain thresholds.

[0061] For specific steps on setting the reference threshold, please refer to [link / reference]. Figure 2 :

[0062] When no target is present in the environment, a total of i frames of signals are transmitted, and after receiving and mixing, a total of i frames of intermediate frequency data G1, G2, ..., G are obtained. i Then perform Fourier transforms on them respectively to obtain J1, J2, ..., J i The modulo subtraction of adjacent frames after Fourier transform yields L1, L2, ..., L... i-1 Then, starting from L1, L2, ..., L... i-1 Select the maximum value from the given values, i.e., M1 = max(L1), M2 = max(L2), ... M i-1 =max(L i-1 After averaging, the lower limit of the frequency domain threshold is obtained as t1 = (M1 + M2 + ... + M...). i-1 ) / (i-1);

[0063] When a pre-defined target appears in the environment, a total of i frames of signals are transmitted, and after receiving and mixing, a total of i frames of intermediate frequency data H1, H2, ..., H are obtained. i Then perform Fourier transforms on them respectively to obtain B1, B2, ..., B i After Fourier transform, the data of adjacent frames are modulo-subtracted to obtain C1, C2, ..., C... i-1 Then, from C1, C2, ..., C i-1 Select the maximum value from the given values, i.e., D1 = max(C1), D2 = max(C2), ... D i-1 =max(C i-1 After averaging, the lower limit of the frequency domain threshold is obtained as t2 = (D1 + D2 + ... + D). i-1 ) / (i-1);

[0064] Finally, the reference threshold T is obtained by combining the upper and lower limits of the frequency domain threshold according to T = (t1 + t2) / 2.

[0065] S2. Set up a storage space for storing targetless measurement results, perform shift storage and dynamic averaging on the targetless measurement results, and perform Fourier transform to obtain environmental data.

[0066] Set up a storage space. First, perform shift register and dynamic averaging on the data G obtained in step S1, then perform a Fourier transform to obtain data P. Then execute the subsequent step S3. Whenever a target-free situation is detected, perform shift register and dynamic averaging, then perform a Fourier transform to update data P. For details on obtaining the initial environmental data, please refer to [link to specific steps]. Figure 3 :

[0067] Set up a storage space to store i-frame data. Store the intermediate frequency data G1, G2, ..., Gi of i-frames after mixing and acquisition into the storage space. Average calculation yields Fk = (G1 + G2 + ... + Gi) / i, where the sampling frame number k = 1. Perform Fourier transform on Fk to obtain its spectrum P, which is the environmental data of the initial situation.

[0068] S3. The real-time acquired detection data and environmental data are modulo-divided in the frequency domain and subtracted. The subtraction result is compared with a reference threshold to determine whether a target exists. If a target exists, the distance between the target and the radar is calculated.

[0069] For detailed steps regarding the target detection process in the environment, please refer to [link / reference]. Figure 4 Step S3 specifically includes the following steps:

[0070] S31. Detection begins. Radar signal R1 is continuously transmitted, and echo signal R2 is received. R1 and R2 are mixed and sampled to obtain intermediate frequency data. Then, Fourier transform is performed to obtain data Y. After that, the data P stored in step S2 and the obtained data Y are subjected to modulo operation.

[0071] S32. Subtract the modulus of the data Y obtained in step S31 from the modulus of the data P stored in step S2 to obtain the subtraction result X. Based on the comparison between the subtraction result X and the reference threshold T obtained in step S1, determine whether there is a target in the environment.

[0072] If the subtraction result X is greater than the reference threshold T, it indicates that a target exists. The distance between the target and the radar can be calculated, and then step S3 is continued for continuous detection.

[0073] If the subtraction result X is less than the reference threshold T, it means that there is no target to be detected and only background data exists. The background data at this time is shifted and registered to update the data P stored in the space in step S2, and then step S3 is continued to be executed for continuous detection.

[0074] As an optional implementation, please refer to the specific steps for updating the storage space. Figure 5 :

[0075] During the update process, the storage space can store i-frame data. First, the initially acquired frame signal G is stored. k(k=1) Delete, and then introduce the newly acquired frame signal G into the storage space. i+k The total amount of data in the storage space remains constant; the sampling frame number k is incremented by 1, i.e., k = k + 1, and then the data in the storage space is averaged to obtain F. k =(G k +…+G i+k-1 ) / i; Finally, for F k Perform a Fourier transform to obtain the spectrum P, which is the updated environmental data. Then continue to execute the above step S3.

[0076] Compared to existing technologies, this invention transmits a frequency-modulated continuous wave signal to the environment under test, performing two measurements: one with a preset target and one without. A reference threshold is set based on the results of the two measurements. A storage space is set up to first perform shift register and dynamic averaging on the measurement results without a target, followed by a Fourier transform to obtain the initial environmental data. Whenever a target-free condition is detected, the data is shift registered and dynamically averaged, followed by a Fourier transform to update the environmental data. After detection begins, the real-time acquired data is moduloed with the initial environmental data in the frequency domain and subtracted. The subtraction result is compared with the threshold to determine whether a target exists and to obtain the target distance information. This invention provides more accurate environmental information modeling. After shift register and dynamic averaging, it can detect the environmental background and its changes in real time. Furthermore, this invention does not require processing in the time domain, avoiding the complex operation of time-domain alignment of the received environmental echoes, reducing system complexity and cost, and meeting the needs of radar detection, positioning, security, and monitoring applications.

[0077] See Figure 6 This embodiment also provides a radar environmental background interference frequency domain suppression system, including:

[0078] The threshold module is used to process the intermediate frequency data of the i-frame after mixing acquisition under the conditions of the presence and absence of the target in the environment to obtain the upper and lower limits t1 and t2 of the frequency domain threshold, and finally generate the reference threshold T, which is then output to the decision module.

[0079] The storage module is used to update and store the intermediate frequency data after mixing and acquisition, and to perform averaging operations on these data to obtain environmental information, which is then output to the detection module.

[0080] The detection module is used to perform frequency domain modulus processing on the newly acquired intermediate frequency data of the mixer, then subtract it from the environmental information, and output the subtraction result to the decision module;

[0081] The decision module compares the subtraction output value X of the detection module with the threshold T to determine whether a target exists. If the subtraction result X is greater than the threshold T, it means that a target has been detected, and the distance information between the target and the radar can be calculated. If the subtraction result X is less than the threshold T, it means that no target has been detected, and a flag is output to the storage space module to start environmental data updates.

[0082] Compared with existing technologies, this invention provides more accurate modeling of environmental information. After shift register and dynamic averaging processing, it can detect the environmental background and its changes in real time. Furthermore, this invention does not require processing in the time domain, avoiding the complex operation of time domain alignment of the received environmental echoes, reducing the complexity and cost of system implementation, and meeting the needs of radar detection, positioning, security, monitoring and other applications.

[0083] like Figure 7 As shown, the environmental background interference frequency domain suppression system of the radar described in this invention is connected to the radar antenna array and the subsequent target data processing device, respectively.

[0084] This embodiment also provides a radar environmental background interference frequency domain suppression device, including:

[0085] At least one processor;

[0086] At least one memory for storing at least one program;

[0087] When the at least one program is executed by the at least one processor, the at least one processor implements Figure 1 The method shown.

[0088] This embodiment of the radar environmental background interference frequency domain suppression device can execute the radar environmental background interference frequency domain suppression method provided in the method embodiment of the present invention, and can execute any combination of the implementation steps of the method embodiment, and has the corresponding functions and beneficial effects of the method.

[0089] This application also discloses a computer program product or computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device can read the computer instructions from the computer-readable storage medium and execute the computer instructions, causing the computer device to perform... Figure 1 The method shown.

[0090] This embodiment also provides a storage medium storing instructions or programs that can execute the radar environmental background interference frequency domain suppression method provided in the method embodiment of the present invention. When the instructions or programs are run, any combination of implementation steps of the method embodiment can be executed, and the method has the corresponding functions and beneficial effects.

[0091] In some alternative embodiments, the functions / operations mentioned in the block diagrams may not occur in the order shown in the operation diagrams. For example, depending on the functions / operations involved, two consecutively shown blocks may actually be executed substantially simultaneously, or the blocks may sometimes be executed in reverse order. Furthermore, the embodiments presented and described in the flowcharts of this invention are provided by way of example to provide a more comprehensive understanding of the technology. The disclosed methods are not limited to the operations and logic flows presented herein. Alternative embodiments are contemplated in which the order of various operations is altered and sub-operations described as part of a larger operation are executed independently.

[0092] Furthermore, although the invention has been described in the context of functional modules, it should be understood that, unless otherwise stated, one or more of the described functions and / or features may be integrated into a single physical device and / or software module, or one or more functions and / or features may be implemented in a separate physical device or software module. It is also understood that a detailed discussion of the actual implementation of each module is unnecessary for understanding the invention. Rather, given the properties, functions, and internal relationships of the various functional modules in the apparatus disclosed herein, the actual implementation of the module will be understood within the scope of conventional skill of an engineer. Therefore, those skilled in the art can implement the invention as set forth in the claims using ordinary techniques without excessive experimentation. It is also understood that the specific concepts disclosed are merely illustrative and not intended to limit the scope of the invention, which is determined by the full scope of the appended claims and their equivalents.

[0093] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, essentially, or the part that contributes to the prior art, or a portion 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 this 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.

[0094] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device.

[0095] More specific examples of computer-readable media (a non-exhaustive list) include: electrical connections (electronic devices) having one or more wires, portable computer disk drives (magnetic devices), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Furthermore, computer-readable media can even be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in computer memory.

[0096] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0097] In the foregoing description of this specification, references to terms such as "one embodiment," "another embodiment," or "some embodiments" indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0098] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

[0099] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the above embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. A frequency domain method for suppressing environmental background interference in radar, characterized in that, Includes the following steps: Based on radar signals, two measurements are performed: one with a preset target and one without. A reference threshold is then set based on the results of the two measurements. Set up a storage space to store the targetless measurement results, perform shift registration and dynamic averaging on the targetless measurement results, and perform Fourier transform to obtain environmental data; The real-time collected detection data and environmental data are moduloed in the frequency domain and subtracted. The subtraction result is compared with a reference threshold to determine whether a target exists. The step of taking the modulus of the real-time collected detection data and the environmental data in the frequency domain and subtracting them, then comparing the subtraction result with a reference threshold to determine whether a target exists includes: Continuously transmit radar signal R1, receive echo signal R2, mix and sample signals R1 and R2 to obtain intermediate frequency data, and perform Fourier transform on the intermediate frequency data to obtain data Y; Perform modulo operation on the environmental data P stored in the storage space and the obtained data Y; Subtract the modulus of the environmental data P from the modulus of the obtained data Y to obtain the subtraction result X; Based on the comparison between the subtraction result X and the reference threshold T, determine whether there is a target in the environment; If the subtraction result X is greater than the reference threshold T, it indicates that a target exists; if the subtraction result X is less than the reference threshold T, it indicates that no target exists and only background data exists. The environmental data P in the storage space is updated based on this background data.

2. The radar environmental background interference frequency domain suppression method according to claim 1, characterized in that, The process involves performing two measurements based on radar signals, one with a preset target and one without. A reference threshold is then set based on the results of these two measurements, including: In two scenarios, one with no target and one with a preset target, i-frame radar signals are transmitted and the echo signals are received. The transmitted signals and echo signals are mixed and sampled to obtain i-frame intermediate frequency data G in the scenario with no target and i-frame intermediate frequency data H in the scenario with a target. In scenarios without a target, the lower limit of the frequency domain threshold is determined based on the intermediate frequency data G; in scenarios with a preset target, the upper limit of the frequency domain threshold is determined based on the intermediate frequency data H. The reference threshold T is calculated based on the lower limit and upper limit of the frequency domain threshold.

3. The frequency domain suppression method for environmental background interference of radar according to claim 2, characterized in that, In the absence of a target scenario, determining the lower limit of the frequency domain threshold based on the intermediate frequency data G includes: When no target is present in the environment, an i-frame signal is transmitted. After mixing and acquiring the transmitted and received signals, the intermediate frequency data G1, G2, ..., G of the i-frame are obtained. i ; For the intermediate frequency data G1, G2, ..., G of the i-frame respectively i Perform a Fourier transform to obtain J1, J2, ..., J i The modulo subtraction of adjacent frames after Fourier transform yields L1, L2, ..., L... i-1 ; From L1, L2, ..., L i-1 Select the maximum value from the given values, i.e., M1 = max(L1), M2 = max(L2), ... M i-1 = max(L i-1 After averaging, the lower limit of the frequency domain threshold is obtained as t1 = (M1 + M2 + ... + M...). i-1 ) / (i-1).

4. The frequency domain suppression method for environmental background interference of radar according to claim 3, characterized in that, The data from adjacent frames after Fourier transform are modulo-subtracted to obtain L1, L2, ..., L... i-1 ,include: After the intermediate frequency data undergoes Fourier transform, J1, J2, ..., J are obtained. i Since the numbers are complex, the modulo subtraction of adjacent frame data yields L1 = abs(J2) - abs(J1), L2 = abs(J3) - abs(J2), ..., L... i-1 =abs(J i )-abs(J i-1 ).

5. The frequency domain suppression method for environmental background interference of radar according to claim 2, characterized in that, The process involves setting up a storage space for storing targetless measurement results, performing shift register processing and dynamic averaging on the targetless measurement results, and then performing a Fourier transform to obtain environmental data, including: Set up a storage space to store i-frame data, and store the intermediate frequency data G1, G2, ..., G of the i-frame after mixing and acquisition. i Stored in storage space, averaged to obtain F k =(G1+ G2+ …+ G i ) / i, where the sampling frame number k=1, for F k The Fourier transform is performed to obtain its spectrum P, which is the environmental data.

6. The frequency domain suppression method for environmental background interference of radar according to claim 1, characterized in that, Update the environment data P in the storage space using the following method: First, the initially acquired frame signal G... k (k=1) Delete, and then import the newly acquired frame signal G into the storage space. i+k Keep the total amount of data in the storage space constant; The sampling frame number k is incremented by 1, i.e., k = k + 1. Then, the data in the storage space is averaged to obtain F. k =( G k + …+ G i+k-1 ) / i; Finally, regarding F k Perform a Fourier transform to obtain the spectrum P, which is the updated environmental data.

7. A frequency domain suppression method for environmental background interference of radar according to any one of claims 1-6, characterized in that, The radar signal transmitted is a frequency-modulated continuous signal; The frequency of the frequency-modulated continuous signal increases linearly with time; a frequency-modulated continuous signal period is the duration of the signal from the start frequency to the cutoff frequency. A frame of frequency-modulated continuous signal period includes two frequency-modulated continuous signal periods and a frame idle time, starting from the first frequency-modulated continuous signal to the cutoff, followed by the second frequency-modulated continuous signal to the cutoff, and finally the frame idle time. A frame of frequency-modulated continuous signal period is at least greater than two frequency-modulated continuous signal periods.

8. A frequency domain suppression device for environmental background interference of radar, characterized in that, include: At least one processor; At least one memory for storing at least one program; When the at least one program is executed by the at least one processor, the at least one processor implements the method of any one of claims 1-7.

9. A computer-readable storage medium storing a processor-executable program, characterized in that, The processor-executable program, when executed by the processor, is used to perform the method as described in any one of claims 1-7.

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