A target distance detection method and device for moving targets

Abstract

The present application relates to a method and device for detecting the distance of a moving target. In the present technical solution, a dual-time-width waveform signal is emitted to the target, and different distance information is obtained according to the reflected signal of the dual-time-width waveform signal, based on which the Doppler frequency shift (the relative speed of the detection position and the target) is calculated. Specifically, for the dual-time-width waveform signal, since the different time widths lead to different slopes of the modulation signal, the Doppler frequency shift can be measured and calculated by changing this parameter, so that the Doppler frequency shift can be compensated using this modulation method. Then, based on the calculated Doppler frequency shift (the relative speed of the detection position and the target), the distance from the detection position to the target and the speed of the dual-time-width waveform signal are determined.

Description

Technical Field

[0001] The present application relates to the field of target detection technology, and in particular to a target distance detection method and device for a moving target. Background Art

[0002] Currently, proximity detectors generally use FMCW (Frequency Modulated Continuous Wave) radars. FMCW radars transmit continuous waves with changing frequencies during a frequency sweep period. Due to the Doppler effect, the echo emitted by a moving object has a certain frequency difference from the transmitted signal. By measuring the frequency difference, the distance information between the target and the radar can be obtained.

[0003] The sawtooth wave modulated FMCW signal is a linear frequency modulation signal. The amplitude of the transmitted waveform of the modulated signal is fixed, while its frequency changes linearly in the time domain according to the sawtooth wave.

[0004] When the target reflector is stationary, the reflected signal of the target reflector is a replica waveform with a time delay from the transmitted signal. When the target reflector is in motion, the Doppler effect will appear. At the same center frequency, the Doppler frequency shift is only affected by the speed. When the speed increases, the distance from the detection position to the target is affected by the Doppler frequency shift, and a large error will appear, which will have a great impact on the distance calculation of the proximity detector. Summary of the invention

[0005] In order to at least to some extent overcome the problem in the related art that when the target reflector is in motion, the Doppler frequency shift will have a significant impact on the distance calculation from the detection position to the target, the present application provides a target distance detection method and device for a moving target.

[0006] The scheme of this application is as follows:

[0007] According to a first aspect of an embodiment of the present application, a target distance detection method for a moving target is provided, characterized by comprising:

[0008] Using a dual-time-width waveform to linearly modulate the signal to be transmitted, and transmitting the linearly modulated dual-time-width waveform signal to the target to be detected;

[0009] The frequency change corresponding to the first time-width waveform signal in the dual time-width waveform signal is: ;

[0010] The frequency change corresponding to the second time-width waveform signal in the dual time-width waveform signal is: ;

[0011] in, Indicates the frequency change corresponding to the first time-width waveform signal; Indicates the carrier frequency bandwidth; Indicates the distance from the detection position to the target; Indicates the carrier time width of the first waveform; c represents the speed of light; Indicates the frequency change corresponding to the second time-width waveform signal; Indicates the carrier time width of the second waveform;

[0012] The relationship between the detection position and the relative speed of the target and the dual-time width waveform signal is determined as follows:

[0013] ;

[0014] in, Indicates the relative speed between the detection position and the target; Indicates the frequency corresponding to the first time-width waveform signal; Indicates the frequency corresponding to the second time-width waveform signal;

[0015] The conversion yields:

[0016] ;

[0017] set up ;

[0018] but ;

[0019] Based on the relative speed between the detection position and the target, the distance from the detection position to the target and the speed of the dual-time width waveform signal are determined.

[0020] Preferably, determining the distance from the detection position to the target based on the relative speed between the detection position and the target includes:

[0021] Determine the signal modulation type;

[0022] If the signal modulation rises, the display frequency of the target distance is calculated based on the detection position and the relative speed of the target:

[0023] ;

[0024] If the signal modulation decreases, the display frequency of the target distance is calculated based on the detection position and the relative speed of the target:

[0025] ;

[0026] Determine the distance from the detection position to the target based on the target distance display frequency:

[0027] ;

[0028] in, Indicates the display frequency of the target distance; Indicates the real instantaneous distance of the target; Indicates the carrier width.

[0029] Preferably, determining the speed of the dual-time-width waveform signal based on the relative speed of the detection position and the target comprises:

[0030] Get the carrier signal wavelength;

[0031] Determine the speed of the dual-time-width waveform signal based on the carrier signal wavelength and the relative speed between the detection position and the target:

[0032] ;

[0033] in, Indicates the wavelength of the carrier signal; Indicates the speed of the dual-time width waveform signal.

[0034] According to a second aspect of an embodiment of the present application, a target distance detection device for a moving target is provided, comprising:

[0035] Processor and memory;

[0036] The processor and the memory are connected via a communication bus:

[0037] Wherein, the processor is used to call and execute the program stored in the memory;

[0038] The memory is used to store a program, and the program is at least used to execute a target distance detection method for a moving target as described in any one of the above items.

[0039] The technical solution provided by this application may have the following beneficial effects:

[0040] In this technical solution, a dual-time-width waveform signal is emitted to the target, and different distance information is obtained according to the reflected signal of the dual-time-width waveform signal, based on which the Doppler frequency shift (the relative speed between the detection position and the target) is calculated. Specifically, for the dual-time-width waveform signal, since the different time widths lead to different slopes of the modulation signal, the Doppler frequency shift can be measured and calculated by changing this parameter, so that the Doppler frequency shift can be compensated using this modulation method. Then, based on the calculated Doppler frequency shift (the relative speed between the detection position and the target), the distance from the detection position to the target and the speed of the dual-time-width waveform signal are determined.

[0041] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0043] Figure 1 This is a schematic diagram of Doppler frequency shift of a dual-time width waveform signal provided by an embodiment of the present application;

[0044] Figure 2 This is a schematic diagram of a dual-time-width waveform signal provided by an embodiment of the present application. DETAILED DESCRIPTION

[0045] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0046] Embodiment 1

[0047] A target distance detection method for a moving target, comprising:

[0048] Using a dual-time-width waveform to linearly modulate the signal to be transmitted, and transmitting the linearly modulated dual-time-width waveform signal to the target to be detected;

[0049] The frequency change corresponding to the first time-width waveform signal in the dual time-width waveform signal is: ;

[0050] The frequency change corresponding to the second time-width waveform signal in the dual time-width waveform signal is: ;

[0051] in, Indicates the frequency change corresponding to the first time-width waveform signal; Indicates the carrier frequency bandwidth; Indicates the distance from the detection position to the target; Indicates the carrier time width of the first waveform; c represents the speed of light; Indicates the frequency change corresponding to the second time-width waveform signal; Indicates the carrier time width of the second waveform;

[0052] The relationship between the detection position and the relative speed of the target and the dual-time width waveform signal is determined as follows:

[0053] ;

[0054] in, Indicates the relative speed between the detection position and the target; Indicates the frequency corresponding to the first time-width waveform signal; Indicates the frequency corresponding to the second time-width waveform signal;

[0055] The conversion yields:

[0056] ;

[0057] set up ;

[0058] but ;

[0059] Based on the relative speed between the detection position and the target, the distance from the detection position to the target and the speed of the dual-time width waveform signal are determined.

[0060] Figure 1 is a schematic diagram of Doppler frequency shift of a dual-time width waveform signal provided by an embodiment of the present application, referring to Figure 1 , a linearly modulated dual-time-width waveform signal is transmitted to the target to be detected, and different distance information is obtained according to the reflected signal of the dual-time-width waveform signal. The Doppler frequency shift is calculated to decouple the target and perform high-precision anti-interference distance measurement. The schematic diagram of the dual-time-width waveform signal is shown in Figure 2 shown.

[0061] It should be noted that, based on the relative speed between the detection position and the target, determining the distance from the detection position to the target includes:

[0062] Determine the signal modulation type;

[0063] If the signal modulation rises, the display frequency of the target distance is calculated based on the detection position and the relative speed of the target:

[0064] ;

[0065] If the signal modulation decreases, the display frequency of the target distance is calculated based on the detection position and the relative speed of the target:

[0066] ;

[0067] Determine the distance from the detection position to the target based on the target distance display frequency:

[0068] ;

[0069] in, Indicates the display frequency of the target distance; Indicates the real instantaneous distance of the target; Indicates the carrier width.

[0070] It should be noted that the speed of the dual-time-width waveform signal is determined based on the relative speed of the detection position and the target, including:

[0071] Get the carrier signal wavelength;

[0072] Determine the speed of the dual-time-width waveform signal based on the carrier signal wavelength and the relative speed between the detection position and the target:

[0073] ;

[0074] in, Indicates the wavelength of the carrier signal; Indicates the speed of the dual-time width waveform signal.

[0075] It should be noted that It can be seen that at the same center frequency, the Doppler shift is only affected by the speed. When the speed increases, the distance from the detection position to the target is affected by the Doppler shift, and a large error will occur, which will have a greater impact on the distance calculation of the proximity detector.

[0076] Therefore, in this technical solution, a dual-time-width waveform signal is emitted to the target, and different distance information is obtained according to the reflected signal of the dual-time-width waveform signal, based on which the Doppler frequency shift (the relative speed between the detection position and the target) is calculated. Specifically, for the dual-time-width waveform signal, since the different time widths lead to different slopes of the modulation signal, the Doppler frequency shift can be measured and calculated by changing this parameter, so that the Doppler frequency shift can be compensated using this modulation method. Then, based on the calculated Doppler frequency shift (the relative speed between the detection position and the target), the distance from the detection position to the target and the speed of the dual-time-width waveform signal are determined.

[0077] The technical solution can accurately calculate the distance from the detection position to the target and the speed of the dual-time-width waveform signal by selecting different waveforms and frequencies of the dual-time-width waveform signal.

[0078] Embodiment 2

[0079] According to a second aspect of an embodiment of the present application, a target distance detection device for a moving target is provided, comprising:

[0080] Processor and memory;

[0081] The processor and the memory are connected via a communication bus:

[0082] Wherein, the processor is used to call and execute the program stored in the memory;

[0083] The memory is used to store a program, and the program is at least used to execute a target distance detection method for a moving target as described in any one of the above items.

[0084] It can be understood that the same or similar parts of the above embodiments can be referenced to each other, and the contents not described in detail in some embodiments can refer to the same or similar contents in other embodiments.

[0085] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0086] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0087] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0088] The storage medium mentioned above can be a read-only memory, a magnetic disk or an optical disk, etc.

[0089] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0090] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A target distance detection method for a moving target, characterized in that: include: Using a dual-time-width waveform to linearly modulate the signal to be transmitted, and transmitting the linearly modulated dual-time-width waveform signal to the target to be detected; The frequency change corresponding to the first time-width waveform signal in the dual time-width waveform signal is: ; The frequency change corresponding to the second time-width waveform signal in the dual time-width waveform signal is: ; in, Indicates the frequency change corresponding to the first time-width waveform signal; Indicates the carrier frequency bandwidth; Indicates the distance from the detection position to the target; Indicates the carrier time width of the first waveform; c represents the speed of light; Indicates the frequency change corresponding to the second time-width waveform signal; Indicates the carrier time width of the second waveform; The relationship between the detection position and the relative speed of the target and the dual-time width waveform signal is determined as follows: ； in, Indicates the relative speed between the detection position and the target; Indicates the frequency corresponding to the first time-width waveform signal; Indicates the frequency corresponding to the second time-width waveform signal; The conversion yields: ； set up ; but ; Based on the relative speed between the detection position and the target, the distance from the detection position to the target and the speed of the dual-time width waveform signal are determined.

2. The method according to claim 1, characterized in that Based on the relative speed between the detection position and the target, the distance from the detection position to the target is determined, including: Determine the signal modulation type; If the signal modulation rises, the display frequency of the target distance is calculated based on the detection position and the relative speed of the target: ； If the signal modulation decreases, the display frequency of the target distance is calculated based on the detection position and the relative speed of the target: ； Determine the distance from the detection position to the target based on the target distance display frequency: ； in, Display frequency indicating target distance; Indicates the real instantaneous distance of the target; Indicates the carrier width.

3. The method according to claim 1, characterized in that Determine the speed of the dual-width waveform signal based on the relative speed of the detection position and the target, including: Get the carrier signal wavelength; Determine the speed of the dual-time-width waveform signal based on the carrier signal wavelength and the relative speed between the detection position and the target: ； in, Indicates the wavelength of the carrier signal; Indicates the speed of the dual-time width waveform signal.

4. A target distance detection device for a moving target, characterized in that: include: Processor and memory; The processor and the memory are connected via a communication bus: Wherein, the processor is used to call and execute the program stored in the memory; The memory is used to store a program, and the program is at least used to execute a target distance detection method for a moving target as described in any one of claims 1-3.

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