CN114706065A - Distance measurement method and device, target detection method and device - Google Patents

Abstract

The application provides a distance measuring method, which is used for measuring the distance between a frequency modulation continuous wave radar and a target to be measured in the signal range of the frequency modulation continuous wave radar, and comprises the following steps: determining an echo spectrogram corresponding to the radar echo signal based on the radar echo signal; determining N echo reflection peaks corresponding to the echo spectrogram based on the echo spectrogram, wherein N is a positive integer greater than or equal to 3; and determining the distance information between the target to be detected and the frequency modulation continuous wave radar based on the N echo reflection peaks. The distance measuring method can obtain the actual distance of the target to be measured based on the radar echo signal, reduce the distance misdetection probability caused by multiple reflection of the radar signal, reduce the probability of occurrence of a radar measurement blind area, and improve the reliability of radar detection.

Description

Distance measurement method and device, target detection method and device

technical field

The present application relates to the field of radar technology, and in particular to a distance measurement method and device, a target detection method and device, a water level measurement method for an irrigation ditch, a method for detecting remaining materials in a bin, a surveying and mapping method, electronic equipment, and computer-readable storage medium.

Background technique

With the development of radar technology, Frequency Modulated Continuous Wave (FMCW) radar is more and more widely used. However, affected by the working parameters of the FMCW radar (such as transmit power, antenna gain or filter parameters) and application scenarios (such as being too close to the target to be measured), the signal transmitted by the FMCW radar is prone to multiple reflections. Multiple reflections will lead to false distance measurement, causing blind spots for radar measurement and affecting the detection reliability of radar.

SUMMARY OF THE INVENTION

In view of this, the embodiments of the present application provide a distance measurement method, a target detection method, a distance measurement device, a target detection device, a water level measurement method for an irrigation ditch, a method for detecting the remaining material of a material box, a surveying and mapping method, electronic equipment and a computer A readable storage medium is provided to solve the technical problem in the prior art that the signal transmitted by the FMCW radar is repeatedly reflected, resulting in a false distance measurement.

According to a first aspect of the embodiments of the present application, a distance measurement method is provided for measuring the distance between a frequency-modulated continuous wave radar and a target to be measured located within a signal range of the frequency-modulated continuous wave radar, and the distance measurement method includes: Based on the radar echo signal, determine the echo spectrogram corresponding to the radar echo signal; based on the echo spectrogram, determine N echo reflection peaks corresponding to the echo spectrogram, where N is a positive integer greater than or equal to 3; based on N It can determine the distance information between the target to be measured and the FM continuous wave radar.

In one embodiment, based on the echo spectrogram, determining N echo reflection peaks corresponding to the echo spectrogram includes: scanning the echo spectrogram gradually along the frequency axis of the coordinate axis of the echo spectrogram, and will exceed the frequency of the echo spectrogram. The peak of the preset amplitude threshold is determined as the echo reflection peak, so as to determine N echo reflection peaks.

In one embodiment, determining the distance information between the target to be measured and the FMCW radar based on the N echo reflection peaks includes: determining the spectral coordinates corresponding to the N echo reflection peaks; based on the N echo reflection peaks The spectral coordinates corresponding to the peaks are used to determine the distance information between the target to be measured and the FM CW radar.

In one embodiment, determining the distance information between the target to be measured and the frequency-modulated continuous wave radar based on the spectral coordinates corresponding to the N echo reflection peaks includes: for the N echo reflection peaks, based on the M+1th The spectral coordinates corresponding to the echo reflection peaks and the spectral coordinates corresponding to the M-th echo-reflection peak are determined, and the spectral coordinate difference corresponding to the M-th echo-reflection peak is determined to determine N-1 corresponding to the N echo-reflection peaks. spectral coordinate difference, where M is a positive integer less than or equal to N-1; if the absolute value of the difference between each adjacent two spectral coordinate differences in the N-1 spectral coordinate differences is within the first threshold, then The distance information is determined based on the N-1 spectral coordinate differences and the sampling frequency corresponding to the echo spectrogram.

In one embodiment, determining the distance information based on the N-1 spectral coordinate differences and the sampling frequency corresponding to the echo spectrogram includes: determining, based on the N-1 spectral coordinate differences, an operation corresponding to the N-1 spectral coordinate differences Spectral coordinate difference; determine the single echo reflection time based on the calculated spectrum coordinate difference and sampling frequency; determine the distance information based on the single echo reflection time and the signal transmission speed of the FM continuous wave radar.

In one embodiment, based on the N-1 spectral coordinate differences, determining the operational spectral coordinate difference corresponding to the N-1 spectral coordinate differences includes: selecting any one of the N-1 spectral coordinate differences as the operational spectral coordinate difference or, determine the average value of N-1 spectral coordinate differences, and use the average value as the calculated spectral coordinate difference; or, based on the hardware parameters of the FM continuous wave radar, determine the preset corresponding to each of the N-1 spectral coordinate differences weights, and based on the preset weights corresponding to the N-1 spectral coordinate differences, perform a weighting operation on the N-1 spectral coordinate differences to obtain the calculated spectral coordinate differences.

In one embodiment, determining the distance information between the target to be measured and the frequency-modulated continuous wave radar based on the spectral coordinates corresponding to the N echo reflection peaks, further comprising: if each adjacent one of the N-1 spectral coordinate differences is If the absolute value of the difference between the two spectral coordinate differences is not within the first threshold, the distance information is determined based on the spectral coordinates and sampling frequency corresponding to the echo reflection peak closest to the coordinate origin of the coordinate axis among the N echo reflection peaks. .

According to a second aspect of the embodiments of the present application, a target detection method is provided, the method comprising: transmitting a radar signal to a target to be measured by using a frequency-modulated continuous wave radar; receiving a radar echo signal reflected by the target to be measured: On the one hand, the distance measurement method processes the radar echo signal to obtain the distance information between the target to be measured and the FMCW radar; based on the distance information and the position information of the FMCW radar, the position information corresponding to the target to be measured is determined.

According to a third aspect of the embodiments of the present application, there is provided a water level testing method for an irrigation ditch, the method comprising: transmitting a radar signal to the irrigation ditch through a frequency-modulated continuous wave radar; receiving a radar echo signal reflected back by the irrigation ditch; In the distance measurement method of the first aspect, the radar echo signal is processed to obtain the distance information between the liquid level of the irrigation ditch and the FM continuous wave radar; based on the distance information, the water level information corresponding to the irrigation ditch is determined.

According to a fourth aspect of the embodiments of the present application, there is provided a method for detecting remaining materials in a bin, the method comprising: transmitting a radar signal to the bottom of the bin through a frequency-modulated continuous wave radar; receiving the reflected radar echo signal; The distance measurement method of the first aspect above processes the radar echo signal to obtain the distance information between the reflecting surface that forms the radar echo signal reflected in the bin and the FM continuous wave radar; based on the distance between the reflecting surface and the FM continuous wave radar The distance information is used to determine the material level information of the material box; based on the material level information, the remaining amount of material in the material box is determined.

According to a fifth aspect of the embodiments of the present application, a surveying and mapping method is provided, the method comprising: transmitting a radar signal to an object to be surveyed and mapped by using a frequency-modulated continuous wave radar; receiving a radar echo signal reflected from the object to be surveyed and mapped; According to the distance measurement method, the radar echo signal is processed to obtain the distance information between the object to be surveyed and the FM continuous wave radar; based on the distance information, the surveying and mapping result data corresponding to the object to be surveyed and mapped is determined.

According to a sixth aspect of the embodiments of the present application, there is provided a distance measurement device for measuring the distance between a frequency-modulated continuous wave radar and a target to be measured located within a signal range of the frequency-modulated continuous wave radar, the device comprising: a first A determination module, configured to determine the echo spectrogram corresponding to the radar echo signal based on the radar echo signal; the second determination module, configured to determine N echo reflection peaks corresponding to the echo spectrogram based on the echo spectrogram , N greater than or equal to 3 is a positive integer; the third determination module is configured to determine the distance information between the target to be measured and the FM continuous wave radar based on N echo reflection peaks.

According to a seventh aspect of the embodiments of the present application, a target detection device is provided, the device comprising: a transmitting module configured to transmit a radar signal to a target to be measured through a frequency-modulated continuous wave radar; a receiving module configured to receive reflections from the target to be measured back The processing module is configured to process the radar echo signal according to the distance measurement method of the first aspect, and obtain the distance information between the target to be measured and the FM continuous wave radar; the position information determination module is configured to be based on The distance information and the position information of the FM continuous wave radar are used to determine the position information corresponding to the target to be measured.

According to an eighth aspect of the embodiments of the present application, there is provided an electronic device, including: a processor; and a memory, where computer program instructions are stored in the memory, and when the computer program instructions are executed by the processor, the processor executes the first method described above. The distance measurement method of the aspect, or the target detection method of the above-mentioned second aspect, or the water level test method of the irrigation ditch of the above-mentioned third aspect, or the residual material detection method of the material box of the above-mentioned fourth aspect, or the above-mentioned fifth aspect. Mapping method.

According to a ninth aspect of the embodiments of the present application, a computer-readable storage medium is provided, where computer program instructions are stored on the computer-readable storage medium, and the computer program instructions, when executed by a processor, cause the processor to execute any of the foregoing embodiments. The distance measurement method provided, or the target detection method of the above-mentioned second aspect, or the water level test method of the irrigation ditch of the above-mentioned third aspect, or the residual material detection method of the material box of the above-mentioned fourth aspect, or the above-mentioned fifth aspect. Mapping method.

The distance measurement method provided by the embodiment of the present application is applied to a frequency-modulated continuous wave radar. Based on the radar echo signal, the echo spectrogram corresponding to the radar echo signal is determined; based on the echo spectrogram, the N corresponding to the echo spectrogram is determined. Based on the N echo reflection peaks, the distance information between the target to be measured and the FM CW radar is determined, so as to obtain the actual distance of the target to be measured and reduce the distance error caused by the multiple reflections of the radar signal. It reduces the probability of radar measurement blind spots and improves the reliability of radar detection.

Description of drawings

FIG. 1 is a schematic flowchart of a distance measurement method provided by an embodiment of the present application.

FIG. 2 is a schematic flowchart of a distance measurement method provided by an embodiment of the present application.

FIG. 3 is a schematic flowchart of a distance measurement method provided by an embodiment of the present application.

FIG. 4 is a schematic flowchart of a distance measurement method provided by an embodiment of the present application.

FIG. 4a shows a schematic flowchart of a distance measurement method provided by an embodiment of the present application.

FIG. 5 is a schematic flowchart of a target detection method provided by an embodiment of the present application.

FIG. 6 is a schematic flowchart of a method for testing the water level of an irrigation ditch according to an embodiment of the present application.

FIG. 7 is a schematic flowchart of a method for detecting remaining materials in a material box according to an embodiment of the present application.

FIG. 8 is a schematic flowchart of a surveying and mapping method according to an embodiment of the present application.

FIG. 9 is a schematic structural diagram of a distance measurement device provided by an embodiment of the present application.

FIG. 10 is a schematic structural diagram of a third determination module provided by an embodiment of the present application.

FIG. 11 is a schematic structural diagram of a second determination module according to an embodiment of the present application.

FIG. 11a is a schematic structural diagram of a subunit for determining the first distance information according to an embodiment of the present application.

FIG. 12 is a schematic structural diagram of a target detection apparatus according to an embodiment of the present application.

FIG. 13 is a schematic structural diagram of a radar measurement apparatus according to an embodiment of the present application.

FIG. 14 is a schematic structural diagram of an electronic device according to an embodiment of the present application.

Detailed ways

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

In the prior art, with the development of radar technology, the application of FMCW radar is more and more extensive. However, affected by the working parameters and application scenarios of FMCW radars, the signals emitted by FMCW radars are prone to multiple reflections. Multiple reflections can lead to false distance measurements, cause blind spots for radar measurements, and affect the detection reliability of radars.

For example: when the distance between the FMCW radar and the target to be measured is relatively close, and the transmitting power or antenna gain of the FMCW radar is too large, the signal sent by the transmitting antenna of the FMCW radar, the signal reflected by the target to be measured once is not completely reflected by the receiving antenna of the FMCW radar. After receiving, the part of the unreceived primary reflected signal is reflected by the receiving antenna, and after it is reflected to the target to be measured again, the signal reflected by the target to be measured twice is received by the receiving antenna again. If the transmit power is strong enough, there will be multiple reflections ( For example: the third reflection signal, and the fourth reflection signal, etc.), due to the close distance between the FMCW radar and the target to be measured, the gain of the received first reflection signal (the real received signal) is smaller than the gain of the second or multiple reflection signals, It will cause the amplitude of the second or multiple reflection signal to be higher than that of the received signal, and when calculating the distance, the signal with the largest amplitude is used for calculation, and the second or multiple reflection signal is used to calculate the distance information, which will lead to false distance measurement. Causes blind spots and affects the detection reliability of the radar.

In order to solve the above problem, an embodiment of the present application provides a distance measurement method applied to an FMCW radar. Based on the radar echo signal, the echo spectrogram corresponding to the radar echo signal is determined; based on the echo spectrogram, the echo spectrum is determined. N echo reflection peaks corresponding to the figure; based on the N echo reflection peaks, determine the distance information between the target to be measured and the FM continuous wave radar, so as to obtain the actual distance of the target to be measured, and reduce the multiple reflections of radar signals due to The resulting probability of distance false detection reduces the probability of radar measurement blind spots and improves the reliability of radar detection.

1 to 14, the distance measurement method, target detection method, distance measurement device, target detection device, water level measurement method of irrigation ditch, remaining material detection method of material box, surveying and mapping method, Electronic devices and computer-readable storage media.

Exemplary Distance Measurement Methods

The distance measurement method provided in the embodiment of the present application is applied to an FMCW radar, and is especially applicable to a millimeter-wave FMCW radar. The millimeter-wave FMCW radar uses the distance measurement method provided by the embodiment of the present application to measure the distance between a single target to be measured and the millimeter-wave FMCW radar located within the short-range radar range of the millimeter-wave FMCW radar.

Specifically, FIG. 1 shows a schematic flowchart of a distance measurement method provided by an embodiment of the present application. As shown in FIG. 1 , the distance measurement method includes the following steps.

S101: Determine an echo spectrogram corresponding to the radar echo signal based on the radar echo signal.

Specifically, the transmitting antenna of the FMCW radar sends out a radar signal (electromagnetic wave), the radar signal reflects the echo when it touches the target to be measured, and the radar receiving antenna receives the radar echo signal, and the received radar echo signal needs to be processed to be Subsequent calculations provide the basis. Since the spectrogram can reflect the changing relationship between the amplitude and the frequency, the echo spectrogram corresponding to the radar echo signal is determined based on the radar echo signal, which provides a basis for subsequent calculations.

In an optional embodiment, the radar echo signal is converted from time domain to frequency domain based on a Fast Fourier Transform (Fast Fourier Transform, FFT) algorithm to obtain an echo spectrogram.

Specifically, the received radar echo signal is represented in the time domain, and through FFT transformation, the radar echo signal is transformed into the frequency domain to obtain an echo spectrogram.

S102: Based on the echo spectrogram, determine N echo reflection peaks corresponding to the echo spectrogram.

Specifically, for FMCW radar, the receiving antenna receives a signal reflected once, and a peak corresponding to the echo spectrogram appears. Therefore, N echo reflection peaks corresponding to the echo spectrogram are determined to obtain the target to be measured later. provide the basis for true distance information. The echo spectrogram is detected, and N echo reflection peaks are determined.

In an optional embodiment, N is a positive integer greater than or equal to 3.

S103: Determine the distance information between the target to be measured and the FM continuous wave radar based on the N echo reflection peaks.

Specifically, considering that the radar signal is an ultrasonic wave, the speed of which is much higher than that of the target to be measured. Therefore, it is considered that the target to be measured is in a relatively static state. Therefore, the distance of each of the multiple reflections of the radar signal emitted by the FMCW radar are equal, correspondingly, there should be certain regularity between N echo reflection peaks. By analyzing the regularity of N echo reflection peaks, the distance information between the target to be measured and the FM continuous wave radar is determined.

In the embodiment of the present application, the echo spectrogram corresponding to the radar echo signal is determined based on the radar echo signal; based on the echo spectrogram, N echo reflection peaks corresponding to the echo spectrogram are determined; based on the N echoes Reflection peak, determine the distance information between the target to be measured and the FM continuous wave radar, so as to obtain the actual distance of the target to be measured, reduce the probability of false distance detection caused by multiple reflections of radar signals, and reduce the probability of radar measurement blind spots, Improve the reliability of radar detection.

FIG. 2 is a schematic flowchart of a distance measurement method provided by an embodiment of the present application. As shown in FIG. 2 , based on the echo spectrogram, the step of determining N echo reflection peaks corresponding to the echo spectrogram includes the following steps.

S201: Scan the echo spectrogram step by step along the frequency axis of the coordinate axis of the echo spectrogram, and determine a peak exceeding a preset amplitude threshold as an echo reflection peak.

S202: Determine N echo reflection peaks.

Specifically, the coordinate axis of the echo spectrogram has a frequency axis (generally represented by the X coordinate axis of the conventional coordinate axis) and an amplitude axis (generally represented by the Y coordinate axis of the conventional coordinate axis). The spectrum value range of the spectrum axis is related to the sampling frequency of the FMCW radar and the number of FFT points. The unit of the spectrum axis is frequency (Hz), and the unit of the amplitude axis is amplitude (dBm). Based on the parameters of the radar signal transmitted by the FMCW radar, the amplitude threshold is preset in advance, and along the frequency axis of the coordinate axis of the echo spectrogram, from the beginning to the end, the echo spectrogram is gradually scanned. peak, which was identified as the echo reflection peak.

For example, if the value range of the abscissa is 0-1200Hz, the amplitude threshold is preset to 500dBm in advance, and the echo spectrogram is gradually scanned along the abscissa to obtain the amplitude value of the Y-axis. The peak exceeding 500dBm is counted as 1 echo reflection peaks, thereby obtaining N echo reflection peaks.

In this embodiment of the present application, the amplitude threshold is preset in advance, and along the frequency axis of the coordinate axis of the echo spectrogram, the echo spectrogram is gradually scanned to determine the peak exceeding the preset amplitude threshold as the echo reflection peak, thereby The purpose of obtaining N echo reflection peaks is achieved, which provides a basis for determining the distance information between the target to be measured and the FM continuous wave radar by analyzing the regularity of the N echo reflection peaks.

FIG. 3 is a schematic flowchart of a distance measurement method provided by an embodiment of the present application. As shown in FIG. 3 , the step of determining the distance information between the target to be measured and the FMCW radar based on N echo reflection peaks includes the following steps.

S301: Determine the spectral coordinates corresponding to each of the N echo reflection peaks.

Specifically, after obtaining N echo reflection peaks, based on the spectral axis of the coordinate axis of the echo spectrogram, the spectral coordinates corresponding to each of the N echo reflection peaks are obtained (that is, the corresponding N echo reflection peaks are obtained. spectrum).

S302: Determine the distance information between the target to be measured and the frequency-modulated continuous wave radar based on the spectral coordinates corresponding to the N echo reflection peaks.

Specifically, the distance of each of the multiple reflections of the radar signal transmitted by the FMCW radar is equal. Accordingly, there should be a certain regularity between the N echo reflection peaks. The distance between the N echo reflection peaks The regularity is also reflected in the spectral coordinates corresponding to the N echo reflection peaks. By analyzing the spectral coordinates corresponding to the N echo reflection peaks, the distance information between the target to be measured and the FM CW radar can be determined.

In the embodiment of the present application, on the spectral axis of the coordinate axis of the echo spectrogram, the spectral coordinates corresponding to each of the N echo reflection peaks are obtained, and by analyzing the spectral coordinates corresponding to each of the N echo reflection peaks, N echo reflection peaks are obtained. There should also be regularity between the echo reflection peaks, and the analyzed regularity should be combined with the characteristic that the distance of each multiple reflection of the radar signal is equal to determine the distance between the target to be measured and the FM continuous wave radar. information.

FIG. 4 is a schematic flowchart of a distance measurement method provided by an embodiment of the present application. As shown in FIG. 4 , the step of determining the distance information between the target to be measured and the FMCW radar based on the spectral coordinates corresponding to each of the N echo reflection peaks includes the following steps.

S401: For the N echo reflection peaks, based on the spectral coordinates corresponding to the M+1 th echo reflection peak and the spectral coordinates corresponding to the M th echo reflection peak, determine the spectral coordinates corresponding to the M th echo reflection peak difference to determine the N-1 spectral coordinate differences corresponding to the N echo reflection peaks.

Illustratively, M is a positive integer less than or equal to N-1.

Specifically, subtract the spectral coordinate corresponding to the previous echo reflection peak from the spectral coordinate corresponding to the latter echo reflection peak to obtain a spectral coordinate difference, and repeat the subtraction process for the N echo reflection peaks to obtain N-1 spectral coordinate differences corresponding to the N echo reflection peaks.

S402: If the absolute value of the difference between each adjacent two spectral coordinate differences in the N-1 spectral coordinate differences is within the first threshold, then based on the sampling corresponding to the N-1 spectral coordinate differences and the echo spectrogram frequency, to determine distance information.

Specifically, comparing the N-1 spectral coordinate differences, if the absolute value of the difference between each adjacent two spectral coordinate differences in the N-1 spectral coordinate differences is within the first threshold (that is, the N-1 spectral coordinate differences The spectral coordinate differences are similar), indicating that the echo reflection peaks after the first echo reflection peak are all formed by multiple reflections. Since the distances of each of the multiple reflections are equal, theoretically, the N-1 spectral coordinate differences should also be equal, and the distance corresponding to this theoretically equal spectral coordinate difference is the distance to be The distance information between the target and the FM continuous wave radar. The distances corresponding to the theoretically equal spectral coordinate differences need to be determined based on the N-1 spectral coordinate differences and the sampling frequency corresponding to the echo spectrogram (ie, the sampling frequency of the FMCW radar).

In the embodiment of the present application, for N echo reflection peaks, the spectral coordinates corresponding to the previous echo reflection peak are subtracted from the spectral coordinates corresponding to the latter echo reflection peak to obtain N- corresponding to the N echo reflection peaks. 1 spectral coordinate difference, compare the N-1 spectral coordinate differences, if the N-1 spectral coordinate differences are similar, then based on the N-1 spectral coordinate difference and the sampling frequency corresponding to the echo spectrogram, the target to be tested and the FMCW are obtained. Radar distance information. Obtaining distance information through the above steps reduces the probability of mistaking the secondary or multiple reflected signals as received signals to obtain erroneous distance information, thereby reducing the probability of false distance detection caused by multiple reflections of radar signals, and reducing the occurrence of radar measurement blind spots. probability and improve the reliability of radar detection.

In an optional embodiment, as shown in FIG. 4 , the step of determining the distance information between the target to be measured and the FMCW radar based on the spectral coordinates corresponding to the N echo reflection peaks further includes the following steps.

S403: If the absolute value of the difference between each adjacent two spectral coordinate differences in the N-1 spectral coordinate differences is not within the first threshold, then based on the N echo reflection peaks that are closest to the coordinate origin of the coordinate axis The spectral coordinates and sampling frequency corresponding to the echo reflection peaks determine the distance information.

Specifically, comparing the N-1 spectral coordinate differences, if the absolute value of the difference between each adjacent two spectral coordinate differences in the N-1 spectral coordinate differences is not within the first threshold (that is, the N-1 spectral coordinate differences Spectral coordinate difference is relatively large), it means that after the signal transmitted by the FMCW radar is transmitted to the target to be measured, there is no regular multiple reflections, and the radar receiving antenna receives the radar echo signal with interference signals. The distance calculation is performed based on the spectral coordinates corresponding to the primary reflection signal received by the radar receiving antenna (that is, the spectral coordinates corresponding to the echo reflection peak closest to the coordinate origin of the coordinate axis among the N echo reflection peaks).

Specifically, through the spectral coordinates and sampling frequency corresponding to the echo reflection peak closest to the coordinate origin of the coordinate axis among the N echo reflection peaks, determine the first echo reflection time (that is, the first time the radar signal is transmitted to the waiting time) The distance information is determined by calculating the first echo reflection time and the signal transmission speed of the FMCW radar (generally considered to be the speed of light).

Exemplarily, the distance information is determined by multiplying the first echo reflection time and the speed of light and dividing by 2.

In the embodiment of the present application, considering that no regular multiple reflections are formed, the spectral coordinates and sampling frequency corresponding to the primary reflection signal received by the radar receiving antenna are calculated to obtain the distance between the target to be measured and the FMCW radar. information.

FIG. 4a shows a schematic flowchart of a distance measurement method provided by an embodiment of the present application. As shown in Figure 4a, the step of determining the distance information between the target to be measured and the FMCW radar based on the spectral coordinates corresponding to the N echo reflection peaks includes the following steps.

S4021: Based on the N-1 spectral coordinate differences, determine the operational spectral coordinate differences corresponding to the N-1 spectral coordinate differences.

Specifically, although theoretically, the N-1 spectral coordinate differences should be equal, in practice, the N-1 spectral coordinate differences may be slightly different. Therefore, each of the N-1 spectral coordinate differences When the absolute value of the difference between the adjacent two spectral coordinate differences is within the first threshold, it is necessary to determine the operational spectral coordinate differences corresponding to the N-1 spectral coordinate differences based on the N-1 spectral coordinate differences, and the operational spectrum will be obtained. The coordinate is equivalent to the theoretically equal spectral coordinate difference, and is calculated by operating the spectral coordinate, which provides the basis for obtaining the distance information between the target to be measured and the FMCW radar.

S4022: Determine a single echo reflection time based on the calculated spectral coordinate difference and the sampling frequency.

S4023: Determine the distance information based on the single echo reflection time and the signal transmission speed of the FM continuous wave radar.

Specifically, the single echo reflection time is the time during which one echo reflection process (that is, the process of transmitting the radar signal to the target to be measured and reflecting back to the radar receiving antenna from the target to be measured) occurs in N echo reflections. The reflection time of the secondary echo and the signal transmission speed of the FMCW radar (generally considered to be the speed of light) are calculated to obtain the distance information between the target to be measured and the FMCW radar.

Exemplarily, the distance information is determined by multiplying the single echo reflection time and the speed of light and dividing by 2.

In the embodiment of the present application, the operation spectrum coordinate differences corresponding to the N-1 spectrum coordinate differences are determined based on the N-1 spectrum coordinate differences, and the obtained operation spectrum coordinate differences and the sampling frequency are substituted into a preset calculation formula to obtain the target to be measured. The distance information between the FM CW radar and the FM CW radar realizes the purpose of determining the distance information between the target to be measured and the FM CW radar based on the spectral coordinates corresponding to each of the N echo reflection peaks.

In an optional embodiment, considering that the absolute value of the difference between each adjacent two spectral coordinate differences in the N-1 spectral coordinate differences is within the first threshold, then the N-1 spectral coordinate differences are mutually The difference is not particularly large. Therefore, any one of the N-1 spectral coordinate differences is selected as the calculated spectral coordinate difference, and the calculated spectral coordinate difference and sampling frequency are calculated to obtain the target to be measured and the frequency-modulated continuous wave radar. distance information.

In a preferred embodiment, the average value of N-1 spectral coordinate differences is obtained by performing an averaging operation on N-1 spectral coordinate differences, and the average of N-1 spectral coordinate differences is used as the calculated spectral coordinate Difference. And the calculation spectrum coordinate difference and sampling frequency are calculated to obtain the distance information between the target to be measured and the FM continuous wave radar.

In another preferred embodiment, based on the hardware parameters of the frequency-modulated continuous wave radar, the preset weights corresponding to the N-1 spectral coordinate differences are determined, and based on the preset weights corresponding to the N-1 spectral coordinate differences, the corresponding preset weights are determined. Perform a weighted operation on the N-1 spectral coordinate differences to obtain the weighted values corresponding to the N-1 spectral coordinate differences, and use the weighted values corresponding to the N-1 spectral coordinate differences as the calculated spectral coordinate differences, and calculate the calculated spectral coordinate differences and sampling values. Calculate the frequency to obtain the distance information between the target to be measured and the FM continuous wave radar.

Specifically, the hardware parameters of the FMCW radar affect the characteristics of the radar circuit, and the characteristics of the radar circuit affect the transfer function, thereby affecting the multiple reflection signal, which in turn affects the N-1 spectral coordinate differences. Therefore, it is necessary to determine the preset weights corresponding to each of the N-1 spectral coordinate differences based on the hardware parameters of the FM continuous wave radar, so as to obtain a more accurate calculated spectral coordinate difference.

For example, due to the influence of the parameters of the filter, it may cause a part of the echo reflection peaks that are relatively early in time among the N echo reflection peaks (that is, in the echo spectrogram, the coordinate origin of the coordinate axis is relatively close The nearest echo reflection peaks) are suppressed, resulting in a relatively front part of the spectral coordinate differences in the N-1 spectral coordinate differences (that is, several spectral coordinate differences that are relatively close to the coordinate origin of the coordinate axis) may be will be smaller. In order to obtain a more accurate calculated spectral coordinate difference, the weight of another part of the spectral coordinate difference that is relatively late in the N-1 spectral coordinate differences is greater than the weight of the relatively front part of the spectral coordinate difference.

Exemplary Object Detection Methods

The target detection method provided by the embodiment of the present application is applied to an FMCW radar, and is especially suitable for a millimeter-wave FMCW radar to perform target detection on a single target to be measured located within the range of a short-range radar.

FIG. 5 is a schematic flowchart of a target detection method provided by an embodiment of the present application. As shown in Figure 5, the target detection method includes the following steps.

S501: Transmit a radar signal to the target to be measured through a frequency-modulated continuous wave radar.

Specifically, a radar signal is transmitted to a single target to be measured located within the short-range radar range of the FMCW radar.

S502: Receive the radar echo signal reflected by the target to be tested.

Specifically, the radar signal is sent to the target to be measured, and the target to be measured reflects the radar signal (ie, the radar echo signal).

S503: Based on the distance measurement method provided in any of the foregoing embodiments, process the radar echo signal to obtain distance information between the target to be measured and the frequency-modulated continuous wave radar.

Specifically, by using the distance measurement method provided in any of the above embodiments, the radar echo signal is processed to obtain accurate distance information between the target to be measured and the FM continuous wave radar.

S504: Based on the distance information between the target to be measured and the FM continuous wave radar and the position information of the FM continuous wave radar, determine the position information corresponding to the target to be measured.

Specifically, the location information of the FMCW radar includes coordinates in the earth coordinate system, and the distance information between the target to be measured and the FMCW radar includes: the relative distance between the target to be measured and the FMCW radar, the distance to be measured The azimuth angle between the target and the FM continuous wave radar, etc. The position information corresponding to the target to be measured is obtained through the coordinates of the FMCW radar, the relative distance between the target to be measured and the FMCW radar, and the azimuth angle between the target to be measured and the FMCW radar.

In the embodiment of the present application, the distance measurement method provided by any of the above embodiments is used to process the radar echo signal to obtain the distance information between the target to be measured and the FM continuous wave radar, and based on the distance between the target to be measured and the FM continuous wave radar The distance information and the position information of the FM continuous wave radar are obtained to obtain the positioning information of the object to be measured, so as to realize the purpose of real-time positioning of the object to be measured.

It should be noted that for different FMCW radar application scenarios, the targets to be measured are not the same. For example: for FMCW radar applied to irrigation ditches, the target to be measured is the liquid level of the irrigation ditches; for FMCW radar applied to unmanned vehicle on-board bins or UAV on-board bins, the target to be measured is the material in the on-board bin; For the application of FMCW radar to exploration drones or exploration unmanned vehicles, the target to be measured is the object to be surveyed and mapped. The FMCW radar may, but is not limited to, the above application scenarios, and accordingly, the target to be measured may be, but not limited to, the above objects.

Water Level Test Method for Exemplary Irrigation Ditch

The method for testing the water level of an irrigation ditch provided in the embodiments of the present application is applied to an FMCW radar. The FMCW radar is set right above the irrigation ditch, and the antenna of the FMCW radar faces the water surface of the irrigation ditch.

FIG. 6 is a schematic flowchart of a method for testing the water level of an irrigation ditch according to an embodiment of the present application. As shown in FIG. 6 , the method for testing the water level of the irrigation ditch includes the following steps.

S601: Transmit radar signals to irrigation ditches through FM continuous wave radar.

S602: Receive the radar echo signal reflected from the irrigation ditch.

S603: Based on the distance measurement method provided in any of the foregoing embodiments, process the radar echo signal to obtain distance information between the liquid level of the irrigation ditch and the frequency-modulated continuous wave radar.

S604: Determine the water level information corresponding to the irrigation ditch based on the distance information between the liquid level of the irrigation ditch and the frequency-modulated continuous wave radar.

Specifically, the FMCW radar set directly above the irrigation ditch transmits radar signals to the irrigation ditch, and receives the radar echo signal reflected back by the irrigation ditch, through the distance measurement provided by any of the above embodiments. The method is to process the radar echo signal to obtain accurate distance information between the liquid level of the irrigation ditch and the FM continuous wave radar, and according to the preset height of the radar and the distance information between the liquid level of the irrigation ditch and the FM continuous wave radar, Obtain the water level information corresponding to the irrigation ditch.

In the embodiment of the present application, through the above steps, the water level information corresponding to the irrigation ditch is obtained in real time, so as to detect the wet condition of the irrigation ditch in real time, and achieve the purpose of reasonable irrigation.

Exemplary Bin Remaining Material Detection Method

The method for detecting the remaining material of the material box provided by the embodiment of the present application is applied to the FMCW radar. FMCW radars are installed on unmanned vehicles or unmanned aircraft. For example: when the FMCW radar is installed on the unmanned vehicle, the FMCW radar is installed at the end of the material box away from the base of the unmanned vehicle (that is, the top of the material box), and the antenna of the FMCW radar faces the material in the vehicle material box.

FIG. 7 is a schematic flowchart of a method for detecting remaining materials in a material box according to an embodiment of the present application. As shown in FIG. 7 , the method for detecting the remaining amount of medicine in the material box includes the following steps.

S701: Send a radar signal to the bottom of the bin through a frequency-modulated continuous wave radar.

Specifically, the materials carried in the material box can be liquids, such as pesticides, or particulates, such as seeds or fertilizers.

S702: Receive the reflected radar echo signal.

S703: Based on the distance measurement method provided in any of the foregoing embodiments, process the radar echo signal to obtain distance information between the reflective surface that forms the radar echo signal reflected in the bin and the FM continuous wave radar.

S704: Determine the material level information of the material box based on the distance information between the reflective surface and the frequency-modulated continuous wave radar.

S705: Determine the material remaining amount of the material box based on the material level information.

Specifically, the FMCW radar installed on the top of the material box transmits radar signals to the bottom of the material box, and receives the reflected radar echo signals, and processes the radar echo signals through the distance measurement method provided by any of the above embodiments. , obtain the distance information between the reflective surface that forms the radar echo signal in the material box and the FM CW radar, and obtain the material level information according to the radar position information and the distance information between the reflective surface and the FM CW radar. Bit information and the volume of the bin to obtain the remaining amount of material in the bin.

In the embodiment of the present application, through the above steps, the remaining amount of materials in the material box is obtained in real time, so as to monitor the remaining amount of materials and achieve the purpose of replenishing materials in time.

Exemplary Mapping Methods

FIG. 8 is a schematic flowchart of a surveying and mapping method according to an embodiment of the present application. As shown in FIG. 8 , the mapping method includes the following steps.

S801: Send a radar signal to the object to be surveyed and mapped through a frequency-modulated continuous wave radar.

Specifically, the objects to be mapped include, but are not limited to, plants, ground, buildings, and other obstacles. The FMCW radar can be installed on the exploration drone or the exploration drone.

S802: Receive the radar echo signal reflected by the object to be mapped.

S803: Based on the distance measurement method provided in any of the foregoing embodiments, process the radar echo signal to obtain distance information between the object to be surveyed and the FM continuous wave radar.

S804: Based on the distance information between the object to be surveyed and the FM continuous wave radar, determine the surveying and mapping result data corresponding to the object to be surveyed and mapped.

Specifically, taking the FMCW radar set on the exploration unmanned aerial vehicle as an example, the radar signal is transmitted to the object to be surveyed and mapped, and the radar echo signal returned by the object to be surveyed and mapped is received. Radar echo signal, obtain the distance information between the object to be surveyed and the FM CW radar, according to the flying height of the exploration drone, the relative height of the radar to the drone and the multiple positions of the object to be surveyed and the FM CW radar obtained The distance information between the radars is used to obtain the surveying and mapping result data corresponding to the object to be surveyed, so as to obtain the operating environment information of the exploration drone.

In the embodiment of the present application, through the above steps, the surveying and mapping result data corresponding to the object to be surveyed and mapped is obtained, and the purpose of obtaining the operation environment information based on the surveying and mapping result data to better assist the operation is achieved.

Exemplary distance measuring device

The distance measurement method provided in the embodiment of the present application is applied to an FMCW radar, and is especially applicable to a millimeter-wave FMCW radar. The millimeter-wave FMCW radar uses the distance measuring device provided by the embodiment of the present application to measure the distance between a single target to be measured and the millimeter-wave FMCW radar within the short-range radar range of the millimeter-wave FMCW radar.

FIG. 9 is a schematic structural diagram of a distance measurement device provided by an embodiment of the present application. As shown in FIG. 9 , the distance measurement apparatus 100 includes a first determination module 101 , a second determination module 102 and a third determination module 103 .

The first determining module 101 is configured to, based on the radar echo signal, determine an echo spectrogram corresponding to the radar echo signal. The second determination module 102 is configured to, based on the echo spectrogram, determine N echo reflection peaks corresponding to the echo spectrogram, where N is greater than or equal to 3 as a positive integer. The third determining module 103 is configured to, based on the N echo reflection peaks, determine the distance information between the target to be measured and the FM continuous wave radar.

The distance measurement device provided by the embodiment of the present application is applied to a frequency-modulated continuous wave radar. Based on the radar echo signal, the echo spectrogram corresponding to the radar echo signal is determined; based on the echo spectrogram, the N corresponding to the echo spectrogram is determined. Based on the N echo reflection peaks, the distance information between the target to be measured and the FM CW radar is determined, so as to obtain the actual distance of the target to be measured and reduce the distance error caused by the multiple reflections of the radar signal. It reduces the probability of radar measurement blind spots and improves the reliability of radar detection.

In one embodiment, the second determination module 102 is further configured to scan the echo spectrogram step by step along the frequency axis of the coordinate axis of the echo spectrogram, and determine the peak exceeding the preset amplitude threshold as the echo reflection peak, to determine the N echo reflection peaks.

FIG. 10 is a schematic structural diagram of a third determination module provided by an embodiment of the present application. As shown in FIG. 9 , the third determination module 103 further includes: a first determination unit 1031 and a second determination unit 1032 .

The first determining unit 1031 is configured to determine the spectral coordinates corresponding to each of the N echo reflection peaks. The second determining unit 1032 is configured to determine the distance information between the target to be measured and the FM continuous wave radar based on the spectral coordinates corresponding to the N echo reflection peaks.

FIG. 11 is a schematic structural diagram of a second determination module according to an embodiment of the present application. As shown in FIG. 11 , the second determining unit 1032 further includes: a spectral coordinate difference determining subunit 10321 , and a first distance information determining subunit 10322 .

The spectral coordinate difference determination subunit 10321 is configured to, for the N echo reflection peaks, determine the Mth echo reflection peak based on the spectral coordinates corresponding to the M+1th echo reflection peak and the spectral coordinates corresponding to the Mth echo reflection peak. The spectral coordinate differences corresponding to the echo reflection peaks are used to determine N-1 spectral coordinate differences corresponding to the N echo reflection peaks, where M is a positive integer less than or equal to N-1. The first distance information determination subunit 10322 is configured to, if the absolute value of the difference between each adjacent two spectral coordinate differences in the N-1 spectral coordinate differences is within the first threshold, then based on the N-1 spectral coordinate differences The sampling frequency corresponding to the difference and echo spectrograms determines the distance information.

In one embodiment, as shown in FIG. 11 , the second determining unit 1032 further includes: a second distance information determining subunit 10323 . The second distance information determination subunit 10323 is configured to, if the absolute value of the difference between each adjacent two spectral coordinate differences in the N-1 spectral coordinate differences is not within the first threshold, then based on the N echo reflection peaks The spectral coordinates and sampling frequency corresponding to the echo reflection peak closest to the coordinate origin of the coordinate axis are used to determine the distance information.

FIG. 11a is a schematic structural diagram of a subunit for determining the first distance information according to an embodiment of the present application. As shown in FIG. 11a, the first distance information determination subunit 10322 further includes: a first determination subunit 103221, a second determination subunit 103222, and a third determination subunit 103223.

The first determining subunit 103221 is configured to, based on the N-1 spectral coordinate differences, determine the operational spectral coordinate differences corresponding to the N-1 spectral coordinate differences. The second determination subunit 103222 is configured to determine the single echo reflection time based on the calculated spectral coordinate difference and the sampling frequency. The third determination subunit 103223 is configured to determine the distance information based on the single echo reflection time and the signal transmission speed of the FM continuous wave radar.

In an optional embodiment, the first determination subunit 103221 is further configured to select any one of the N-1 spectral coordinate differences as the calculated spectral coordinate difference.

In a preferred embodiment, the first determination subunit 103221 is further configured to determine the average value of the N-1 spectral coordinate differences, and use the average value as the calculated spectral coordinate difference.

In another preferred embodiment, the first determination subunit 103221 is further configured to determine the preset weights corresponding to the N-1 spectral coordinate differences based on the hardware parameters of the FM continuous wave radar, and based on the N-1 spectral coordinate differences According to the preset weights corresponding to the differences, a weighted operation is performed on the N-1 spectral coordinate differences to obtain the calculated spectral coordinate differences.

In one embodiment, the first determining module 101 is further configured to, based on a fast Fourier transform algorithm, perform time domain to frequency domain conversion on the radar echo signal to obtain an echo spectrogram.

The specific functions and operations of other modules in the above distance measuring device have been described in detail in the distance measuring methods described in FIG. 1 to FIG. 4 a , and therefore, repeated descriptions thereof will be omitted here.

Exemplary Object Detection Device

The target detection device provided in the embodiment of the present application is applied to an FMCW radar, and is especially suitable for a millimeter-wave FMCW radar to perform target detection on a single target to be measured located within the range of the short-range radar.

FIG. 12 is a schematic structural diagram of a target detection apparatus according to an embodiment of the present application. As shown in FIG. 12 , the target detection apparatus 200 includes: a transmitting module 201 , a receiving module 202 , a processing module 203 and a position information determining module 204 .

The transmitting module 201 is configured to transmit radar signals to the target to be measured through the frequency-modulated continuous wave radar. The receiving module 202 is configured to receive the radar echo signal reflected by the target to be measured. The processing module 203 is configured to, based on the distance measurement method provided in any of the above embodiments, process the radar echo signal to obtain the distance information between the target to be measured and the FM continuous wave radar. The location information determination module 204 is configured to, based on the distance information and the location information of the FM continuous wave radar, determine the location information corresponding to the target to be measured.

The specific functions and operations of the other modules in the above-mentioned target detection apparatus have been described in detail in the target detection method described in FIG. 5 , and therefore, their repeated descriptions will be omitted here.

Considering that FMCW radar is more and more widely used, there are many items to be tested for the measurement of radar performance, and its antenna pattern plays an extremely important role in radar performance. However, to measure the direction map, a professional test environment needs to be built, and the cost is huge.

Exemplary Radar Measurement Device

Other embodiments of the present application further provide a radar measurement device for obtaining the antenna pattern of the radar, which is suitable for measuring the FMCW radar provided in any of the foregoing embodiments to obtain the antenna pattern of the FMCW radar.

Antenna pattern, also known as radiation pattern and far-field pattern, refers to the pattern in which the relative field strength (normalized modulus) of the radiation field changes with the direction at a certain distance from the radar antenna. Usually, the maximum radiation through the radar antenna is used. The directions are represented by two mutually perpendicular plane patterns.

The radar measurement device can be installed in an open test field, or in a test field where there are no reflective objects such as cables or branches in the sky.

FIG. 13 is a schematic structural diagram of a radar measurement apparatus according to an embodiment of the present application. As shown in FIG. 13 , the radar measurement device 1300 includes a wave-absorbing semicircular outer frame 1301 , a movable reflecting member 1302 , and a processor 1303 .

The wave-absorbing semicircle frame 1301 can prevent the radar signal from scattering; the radar to be tested 1304 is arranged at the center of the wave-absorbing semicircle frame 1301, and the antenna surface of the radar to be tested 1304 faces the center of the arc. The movable reflecting member 1302 is disposed inside the wave-absorbing semicircle frame 1301 and slides along the wave-absorbing semicircle frame 1301 for reflecting the radar signal emitted by the radar 1304 under test. The processor 1303 is connected to the radar under test 1304, and is used to control the radar under test 1304 to transmit intermediate frequency signals, and generate an antenna pattern based on the echo signals collected by the movable reflection component 1302 at different positions of the wave absorbing semicircular frame 1301.

Specifically, the processor 1303 controls the antenna of the radar under test 1304 to transmit an intermediate frequency signal, the movable reflection part 1302 slides along the wave-absorbing semicircle frame 1301, and the moving speed of the movable reflection part 1302 is the same as that of the radar signal transmitted by the radar under test 1304. The transmission frequency is adapted so that the moving reflection part 1302 can receive the radar signal transmitted by the radar to be tested 1304 at different positions of the wave-absorbing semicircle outer frame 1301 .

Since the wave-absorbing semicircular frame 1301 is in the shape of a semicircle, it is ensured that the relative distances between the mobile reflecting member 1302 and the radar 1304 to be tested are the same (both are radii) during the test. After the radar under test 1304 transmits the radar signal, it is reflected by the moving reflecting member 1302 , and the echo signal is received by the radar under test and transmitted to the processor 1303 . Since the gain in the normal direction of the antenna is the largest, when the moving reflecting member 1302 is at the 90° position of the arc, the amplitude of the intermediate frequency signal is the strongest. When the moving reflecting member 1302 slides to both sides, the amplitude of the intermediate frequency signal will change. to the processor 1303. The processor reverses the RF power by judging the amplitude of the IF signal to obtain the antenna pattern.

In one embodiment, the wave-absorbing semicircular outer frame 1301 is made of a wave-absorbing material, or an outer frame that satisfies the lightness is prepared and wrapped with a wave-absorbing material.

In one embodiment, the movable reflective member 1302 may be an inverse, triangular in shape.

The radar monitoring device provided in the embodiment of the present application can not only accurately reflect the antenna characteristics of the radar, but also has the characteristics of simplicity and low cost.

Exemplary Electronics

FIG. 14 is a schematic structural diagram of an electronic device according to an embodiment of the present application. As shown in FIG. 14 , electronic device 300 includes one or more processors 310 and memory 320 .

Processor 310 may be a central processing unit (CPU) or other form of processing unit having data processing capabilities and/or instruction execution capabilities, and may control other components in electronic device 300 to perform desired functions.

Memory 320 may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and/or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and/or cache memory, or the like. The non-volatile memory may include, for example, read only memory (ROM), hard disk, flash memory, and the like. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor 310 may execute the program instructions to implement the distance measurement method of the various embodiments of the present application described above, or various implementations The target detection method of the embodiment, the water level test method of the irrigation ditch of the embodiment, the residual material detection method of the material box of the embodiment, the surveying and mapping method of the embodiment, and/or other desired functions.

In one example, the electronic device 300 may also include an input device 330 and an output device 340 interconnected by a bus system and/or other form of connection mechanism (not shown).

Of course, for simplicity, only some of the components in the electronic device 300 related to the present application are shown in FIG. 14 , and components such as buses, input/output interfaces and the like are omitted. Besides, the electronic device 300 may also include any other appropriate components according to the specific application.

Exemplary computer program product and computer readable storage medium

In addition to the methods and apparatuses described above, embodiments of the present application may also be computer program products comprising computer program instructions that, when executed by a processor, cause the processor to perform the above-mentioned "Exemplary Distance Measurements" of this specification The steps in the distance measurement method provided according to the various embodiments of the present application described in the "Method" section, or performing the steps in the target detection method provided according to the various embodiments of the present application described in the above-mentioned "Exemplary target detection method" section of this specification. steps, or perform the steps in the method for testing the water level of an irrigation ditch provided according to various embodiments of the present application described in the above-mentioned "Method for Testing Water Level of an Exemplary Irrigation Ditch" in this specification, or perform the above-mentioned "Method for Testing Water Level of an Exemplary Feed Tank" in this specification. The steps in the method for detecting the remaining material in the material box provided according to the various embodiments of the present application described in the "Remaining Material Detection Method" section, or perform the steps in the "Exemplary Surveying and Mapping Method" section of the present specification described in the above-mentioned section "Exemplary Surveying and Mapping Method" provided according to the various embodiments of the present application. steps in the method of surveying and mapping.

The computer program product can write program codes for performing the operations of the embodiments of the present application in any combination of one or more programming languages, including object-oriented programming languages, such as Java, C++, etc. , also includes conventional step-by-step programming languages, such as "C" language or similar programming languages. The program code may execute entirely on the user's computing device, partly on the user's device, as a stand-alone software package, partly on the user's computing device and partly on a remote computing device, or entirely on the remote computing device or server execute on.

In addition, the embodiments of the present application may also be computer-readable storage media on which computer program instructions are stored, the computer program instructions, when executed by a processor, cause the processor to perform the above-mentioned "exemplary distance" in this specification. The steps in the distance measurement method provided according to the various embodiments of the present application described in the "Measurement Method" section, or in the execution of the target detection method provided according to the various embodiments of the present application described in the above-mentioned "Exemplary target detection method" section of this specification. or perform the steps in the method for testing the water level of an irrigation ditch provided according to various embodiments of the present application described in the above-mentioned “Method for Testing the Water Level of an Exemplary Irrigation Ditch” in this specification, or perform the above-mentioned “Exemplary Feed Tank” in this specification. The steps in the method for detecting the remaining material of the material box provided according to the various embodiments of the present application described in the section "Method for detecting the remaining material of the Steps in the provided mapping method.

The computer-readable storage medium may employ any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may include, for example, but not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses or devices, or a combination of any of the above. More specific examples (non-exhaustive list) of readable storage media include: electrical connections with one or more wires, portable disks, hard disks, random access memory (RAM), read only memory (ROM), erasable programmable read only memory (EPROM or flash memory), optical fiber, portable compact disk read only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

It should be noted that the above enumeration is only specific embodiments of the present application. Obviously, the present application is not limited to the above embodiments, and there are many similar changes. If those skilled in the art directly derive or associate all modifications from the content disclosed in this application, they shall fall within the protection scope of this application.

It should be understood that the qualifiers such as first and second mentioned in the embodiments of the present application are only used to describe the technical solutions of the embodiments of the present application more clearly, and cannot be used to limit the protection scope of the present application.

The above are only preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included within the protection scope of this application.

Claims (15)

1. a distance measuring method, it is characterized in that, for measuring the distance between the frequency-modulated continuous wave radar and the target to be measured within the signal range of the frequency-modulated continuous wave radar, the method comprises: determining the echo spectrogram corresponding to the radar echo signal based on the radar echo signal; Based on the echo spectrogram, determine N echo reflection peaks corresponding to the echo spectrogram, where N is a positive integer greater than or equal to 3; Based on the N echo reflection peaks, the distance information between the target to be measured and the frequency-modulated continuous wave radar is determined. 2. The distance measurement method according to claim 1, wherein the determining, based on the echo spectrogram, N echo reflection peaks corresponding to the echo spectrogram, comprising: Stepwise scan the echo spectrogram along the frequency axis of the coordinate axis of the echo spectrogram, and determine the peak exceeding a preset amplitude threshold as the echo reflection peak, so as to determine the N echo reflections peak. 3. The distance measurement method according to claim 1, wherein, determining the distance information between the target to be measured and the FMCW radar based on the N echo reflection peaks, comprising: determining the spectral coordinates corresponding to each of the N echo reflection peaks; Based on the spectral coordinates corresponding to the N echo reflection peaks, the distance information between the target to be measured and the frequency-modulated continuous wave radar is determined. 4 . The distance measurement method according to claim 3 , wherein the distance between the target to be measured and the FMCW radar is determined based on the corresponding spectral coordinates of the N echo reflection peaks. 5 . Distance information, including: For the N echo reflection peaks, based on the spectral coordinates corresponding to the M+1 th echo reflection peak and the spectral coordinates corresponding to the M th echo reflection peak, determine the corresponding M th echo reflection peak. spectral coordinate differences, to determine N-1 spectral coordinate differences corresponding to the N echo reflection peaks, where M is a positive integer less than or equal to N-1; If the absolute value of the difference between each adjacent two spectral coordinate differences in the N-1 spectral coordinate differences is within the first threshold, then based on the N-1 spectral coordinate differences and the echo spectrum The sampling frequency corresponding to the map determines the distance information. 5. The distance measurement method according to claim 4, wherein, determining the distance information based on the N-1 spectral coordinate differences and the sampling frequency corresponding to the echo spectrogram, comprising: Based on the N-1 spectral coordinate differences, determine the operational spectral coordinate differences corresponding to the N-1 spectral coordinate differences; determining a single echo reflection time based on the calculated spectral coordinate difference and the sampling frequency; The distance information is determined based on the single echo reflection time and the signal transmission speed of the FM continuous wave radar. 6. The distance measurement method according to claim 5, wherein, based on the N-1 spectral coordinate differences, determining the operational spectral coordinate differences corresponding to the N-1 spectral coordinate differences comprises: Select any one of the N-1 spectral coordinate differences as the operational spectral coordinate difference; or, Determine the average value of the N-1 spectral coordinate differences, and use the average value as the calculated spectral coordinate difference; or, Based on the hardware parameters of the FM continuous wave radar, the preset weights corresponding to the N-1 spectral coordinate differences are determined, and based on the preset weights corresponding to the N-1 spectral coordinate differences, the N-1 spectral coordinate differences are determined. -1 spectral coordinate difference is weighted to obtain the operating spectral coordinate difference. 7 . The distance measurement method according to claim 4 , wherein the distance between the target to be measured and the FM continuous wave radar is determined based on the corresponding spectral coordinates of the N echo reflection peaks. 8 . Distance information, also includes: If the absolute value of the difference between each adjacent two spectral coordinate differences in the N-1 spectral coordinate differences is not within the first threshold, then based on the distance between the N echo reflection peaks from the coordinate axis The distance information is determined by the spectral coordinates corresponding to the echo reflection peak closest to the coordinate origin and the sampling frequency. 8. A target detection method, characterized in that the method comprises: Send radar signals to the target to be measured through FM continuous wave radar; receiving the radar echo signal reflected by the target to be measured; Based on the distance measurement method according to any one of claims 1 to 7, the radar echo signal is processed to obtain distance information between the target to be measured and the FM continuous wave radar; Based on the distance information and the position information of the FM continuous wave radar, the position information corresponding to the target to be measured is determined. 9. A water level testing method for irrigation ditches, characterized in that the method comprises: Transmit radar signals to irrigation ditches through FM continuous wave radar; receiving the radar echo signal reflected from the irrigation ditch; Based on the distance measurement method according to any one of claims 1 to 7, the radar echo signal is processed to obtain the distance information between the liquid level of the irrigation ditch and the frequency-modulated continuous wave radar; Based on the distance information, water level information corresponding to the irrigation ditch is determined. 10. A method for detecting the remaining material of a material box, wherein the method comprises: Send radar signals to the bottom of the bin through FM continuous wave radar; Receive the reflected radar echo signal; Based on the distance measurement method according to any one of claims 1 to 7, the radar echo signal is processed to obtain the difference between the reflective surface in the material box that forms the radar echo signal and the frequency-modulated continuous wave radar distance information; Determine the material level information of the material box based on the distance information between the reflecting surface and the FM continuous wave radar; Based on the material level information, the remaining amount of material in the material box is determined. 11. A surveying and mapping method, characterized in that the method comprises: Send radar signals to the object to be surveyed and mapped through frequency-modulated continuous wave radar; receiving the radar echo signal reflected by the object to be surveyed and mapped; Based on the distance measurement method according to any one of claims 1 to 7, the radar echo signal is processed to obtain distance information between the object to be surveyed and the FM continuous wave radar; Based on the distance information, the surveying and mapping result data corresponding to the object to be surveyed and mapped is determined. 12. A distance measuring device, characterized in that it is used to measure the distance between a frequency-modulated continuous wave radar and a target to be measured within a signal range of the frequency-modulated continuous wave radar, the device comprising: a first determining module, configured to determine an echo spectrogram corresponding to the radar echo signal based on the radar echo signal; The second determining module is configured to determine, based on the echo spectrogram, N echo reflection peaks corresponding to the echo spectrogram, where N is greater than or equal to 3 as a positive integer; A third determining module is configured to determine distance information between the target to be measured and the FM continuous wave radar based on the N echo reflection peaks. 13. A target detection device, characterized in that the device comprises: The transmitting module is configured to transmit radar signals to the target to be measured through the FM continuous wave radar; a receiving module, configured to receive the radar echo signal reflected by the target to be measured; a processing module, configured to process the radar echo signal based on the distance measurement method according to any one of claims 1 to 7 to obtain distance information between the target to be measured and the FM continuous wave radar; A location information determination module is configured to determine location information corresponding to the target to be measured based on the distance information and the location information of the FMCW radar. 14. An electronic device comprising: processor; and A memory having computer program instructions stored in the memory which, when executed by the processor, cause the processor to perform the method of any one of claims 1 to 11. 15. A computer-readable storage medium having computer program instructions stored thereon, the computer program instructions, when executed by a processor, cause the processor to perform any one of claims 1 to 11 the method.

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