Distance measurement method and device, target detection method and device

Abstract

The present application provides a distance measurement method for measuring the distance between a frequency modulated continuous wave radar and a target to be measured within the signal range of the frequency modulated continuous wave radar, the method comprising: determining an echo spectrum diagram corresponding to the radar echo signal based on the radar echo signal; determining N echo reflection peaks corresponding to the echo spectrum diagram based on the echo spectrum diagram, where N is a positive integer greater than or equal to 3; determining the distance information between the target to be measured and the frequency modulated continuous wave radar based on the N echo reflection peaks. The distance measurement method provided by the present application can obtain the actual distance of the target to be measured based on the radar echo signal, reduce the probability of distance mismeasurement caused by multiple reflections of the radar signal, reduce the probability of radar measurement blind spots, and improve the reliability of radar detection.

Description

Technical Field

[0001] The present application relates to the field of radar technology, and specifically to a distance measurement method and device thereof, a target detection method and device thereof, a water level testing method for irrigation ditches, a residual material detection method for material boxes, a surveying and mapping method, an electronic device and a computer-readable storage medium. Background Art

[0002] With the development of radar technology, the application of frequency modulated continuous wave (FMCW) radar is becoming more and more widespread. However, due to the influence of FMCW radar's working parameters (such as transmission power, antenna gain or filter parameters) and application scenarios (such as being too close to the target to be measured), the signal emitted by FMCW radar is prone to multiple reflections, which can lead to mismeasurement of distance, create blind spots for radar measurement, and affect the detection reliability of radar. Summary of the invention

[0003] 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 testing method for irrigation ditches, a remaining material detection method for material boxes, a surveying and mapping method, an electronic device and a computer-readable storage medium to solve the technical problem in the prior art that the signal emitted by the FMCW radar is reflected multiple times, resulting in distance mismeasurement.

[0004] According to a first aspect of an embodiment 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 within a signal range of the frequency modulated continuous wave radar, the distance measurement method comprising: determining an echo spectrum diagram corresponding to the radar echo signal based on a radar echo signal; determining N echo reflection peaks corresponding to the echo spectrum diagram based on the echo spectrum diagram, where N is a positive integer greater than or equal to 3; and determining distance information between the target to be measured and the frequency modulated continuous wave radar based on the N echo reflection peaks.

[0005] In one embodiment, based on the echo spectrum diagram, N echo reflection peaks corresponding to the echo spectrum diagram are determined, including: scanning the echo spectrum diagram step by step along the frequency axis of the coordinate axis of the echo spectrum diagram, and determining the peak exceeding a preset amplitude threshold as the echo reflection peak, so as to determine the N echo reflection peaks.

[0006] In one embodiment, determining the distance information between the target to be measured and the frequency modulated continuous wave radar based on N echo reflection peaks includes: determining the frequency spectrum coordinates corresponding to each of the N echo reflection peaks; determining the distance information between the target to be measured and the frequency modulated continuous wave radar based on the frequency spectrum coordinates corresponding to each of the N echo reflection peaks.

[0007] In one embodiment, based on the frequency spectrum coordinates corresponding to each of the N echo reflection peaks, determining the distance information between the target to be measured and the frequency modulated continuous wave radar includes: for the N echo reflection peaks, based on the frequency spectrum coordinates corresponding to the M+1th echo reflection peak and the frequency spectrum coordinates corresponding to the Mth echo reflection peak, determining the frequency spectrum coordinate difference corresponding to the Mth echo reflection peak, so as to determine N-1 frequency spectrum coordinate differences corresponding to the N echo reflection peaks, wherein M is a positive integer less than or equal to N-1; if the absolute value of the difference between each adjacent two frequency spectrum coordinate differences in the N-1 frequency spectrum coordinate differences is within a first threshold, then determining the distance information based on the N-1 frequency spectrum coordinate differences and the sampling frequency corresponding to the echo spectrum diagram.

[0008] In one embodiment, distance information is determined based on N-1 spectrum coordinate differences and a sampling frequency corresponding to an echo spectrum diagram, including: determining an operational spectrum coordinate difference corresponding to the N-1 spectrum coordinate difference based on the N-1 spectrum coordinate differences; determining a single echo reflection time based on the operational spectrum coordinate difference and the sampling frequency; and determining distance information based on a single echo reflection time and a signal transmission speed of a frequency modulated continuous wave radar.

[0009] In one embodiment, based on N-1 spectrum coordinate differences, determining the computational spectrum coordinate difference corresponding to the N-1 spectrum coordinate differences includes: selecting any one of the N-1 spectrum coordinate differences as the computational spectrum coordinate difference; or, determining the average value of the N-1 spectrum coordinate differences, and using the average value as the computational spectrum coordinate difference; or, based on the hardware parameters of the frequency modulated continuous wave radar, determining the preset weights corresponding to each of the N-1 spectrum coordinate differences, and performing a weighted operation on the N-1 spectrum coordinate differences based on the preset weights corresponding to each of the N-1 spectrum coordinate differences to obtain the computational spectrum coordinate difference.

[0010] In one embodiment, the distance information between the target to be measured and the frequency modulated continuous wave radar is determined based on the frequency spectrum coordinates corresponding to each of the N echo reflection peaks, and further includes: if the absolute value of the difference between each two adjacent frequency spectrum coordinate differences in the N-1 frequency spectrum coordinate differences is not within a first threshold, the distance information is determined based on the frequency spectrum 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.

[0011] According to a second aspect of an embodiment of the present application, a target detection method is provided, the method comprising: transmitting a radar signal to a target to be measured by means of a frequency modulated continuous wave radar; receiving a radar echo signal reflected from the target to be measured; processing the radar echo signal based on the distance measurement method of the first aspect described above to obtain distance information between the target to be measured and the frequency modulated continuous wave radar; and determining position information corresponding to the target to be measured based on the distance information and the position information of the frequency modulated continuous wave radar.

[0012] According to a third aspect of an embodiment of the present application, a method for testing the water level of an irrigation ditch is provided, 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 from the irrigation ditch; based on the distance measurement method of the first aspect described above, processing the radar echo signal to obtain distance information between the liquid surface of the irrigation ditch and the frequency modulated continuous wave radar; and determining the water level information corresponding to the irrigation ditch based on the distance information.

[0013] According to a fourth aspect of an embodiment of the present application, a method for detecting remaining material in a material box is provided, the method comprising: transmitting a radar signal to the bottom of the material box by means of a frequency modulated continuous wave radar; receiving a reflected radar echo signal; processing the radar echo signal based on the distance measurement method of the first aspect described above, to obtain distance information between a reflecting surface in the material box that reflects the radar echo signal and the frequency modulated continuous wave radar; determining material level information of the material box based on the distance information between the reflecting surface and the frequency modulated continuous wave radar; and determining the remaining amount of material in the material box based on the material level information.

[0014] According to a fifth aspect of an embodiment 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 means of a frequency modulated continuous wave radar; receiving a radar echo signal reflected from the object to be surveyed and mapped; based on the distance measurement method of the first aspect described above, processing the radar echo signal to obtain distance information between the object to be surveyed and the frequency modulated continuous wave radar; and determining surveying and mapping result data corresponding to the object to be surveyed and mapped based on the distance information.

[0015] According to a sixth aspect of an embodiment of the present application, a distance measurement device is provided for measuring 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 determination module, configured to determine an echo spectrum diagram corresponding to the radar echo signal based on the radar echo signal; a second determination module, configured to determine N echo reflection peaks corresponding to the echo spectrum diagram based on the echo spectrum diagram, where N is a positive integer greater than or equal to 3; and a third determination module, configured to determine the distance information between the target to be measured and the frequency modulated continuous wave radar based on the N echo reflection peaks.

[0016] According to a seventh aspect of an embodiment of the present application, a target detection device is provided, which includes: 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 a radar echo signal reflected from the target to be measured; a processing module, configured to process the radar echo signal using the distance measurement method of the first aspect above, to obtain distance information between the target to be measured and the frequency modulated continuous wave radar; and a position information determination module, configured to determine the position information corresponding to the target to be measured based on the distance information and the position information of the frequency modulated continuous wave radar.

[0017] According to an eighth aspect of an embodiment of the present application, there is provided an electronic device, comprising: a processor; and a memory, in which computer program instructions are stored, and when the computer program instructions are executed by the processor, the processor executes a distance measurement method such as the first aspect mentioned above, or a target detection method such as the second aspect mentioned above, or a water level test method for an irrigation ditch such as the third aspect mentioned above, or a remaining material detection method for a material box such as the fourth aspect mentioned above, or a surveying and mapping method such as the fifth aspect mentioned above.

[0018] According to a ninth aspect of an embodiment of the present application, a computer-readable storage medium is provided, on which computer program instructions are stored. When the computer program instructions are executed by a processor, the processor executes a distance measurement method as provided in any of the above embodiments, or a target detection method as provided in the second aspect, or a water level testing method for an irrigation ditch as provided in the third aspect, or a residual material detection method for a material box as provided in the fourth aspect, or a surveying and mapping method as provided in the fifth aspect.

[0019] The distance measurement method provided in the embodiment of the present application is applied to a frequency modulated continuous wave radar, by determining an echo spectrum diagram corresponding to the radar echo signal based on the radar echo signal; determining N echo reflection peaks corresponding to the echo spectrum diagram based on the echo spectrum diagram; and determining the distance information between the target to be measured and the frequency modulated continuous wave radar based on the N echo reflection peaks, thereby obtaining the actual distance of the target to be measured, reducing the probability of distance mismeasurement caused by multiple reflections of the radar signal, reducing the probability of a radar measurement blind area, and improving the reliability of radar detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The figure is a flow chart of the distance measurement method provided in the embodiment of the present application.

[0021] Figure 2 The figure is a flow chart of the distance measurement method provided in the embodiment of the present application.

[0022] Figure 3 The figure is a flow chart of the distance measurement method provided in the embodiment of the present application.

[0023] Figure 4 The figure is a flow chart of the distance measurement method provided in the embodiment of the present application.

[0024] Figure 4a The figure is a flow chart of the distance measurement method provided in the embodiment of the present application.

[0025] Figure 5 The figure is a flow chart of a target detection method provided in one embodiment of the present application.

[0026] Figure 6Shown is a schematic flow chart of a method for testing the water level of an irrigation ditch provided in one embodiment of the present application.

[0027] Figure 7 The figure is a schematic flow chart of a method for detecting residual material in a material box provided in one embodiment of the present application.

[0028] Figure 8 The figure is a schematic flow chart of a surveying and mapping method provided in one embodiment of the present application.

[0029] Fig. 9 Shown is a schematic structural diagram of a distance measurement device provided in one embodiment of the present application.

[0030] Fig.10 Shown is a schematic diagram of the structure of a third determination module provided in an embodiment of the present application.

[0031] Fig.11 Shown is a schematic diagram of the structure of a second determination module provided in an embodiment of the present application.

[0032] Fig.11a Shown is a schematic structural diagram of a first distance information determination subunit provided in an embodiment of the present application.

[0033] Fig.12 Shown is a schematic structural diagram of a target detection device provided in one embodiment of the present application.

[0034] Fig.13 Shown is a schematic structural diagram of a radar measuring device provided in one embodiment of the present application.

[0035] Fig.14 Shown is a schematic structural diagram of an electronic device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0037] In the prior art, with the development of radar technology, FMCW radar is being used more and more widely. However, due to the influence of FMCW radar's working parameters and application scenarios, the signal emitted by FMCW radar is prone to multiple reflections, which can lead to mismeasurement of distance, create blind spots for radar measurement, and affect the detection reliability of radar.

[0038] For example, when the FMCW radar is close to the target to be measured, and the transmission power or antenna gain of the FMCW radar is too large, the signal emitted by the transmitting antenna of the FMCW radar, the signal reflected once by the target to be measured is not completely received by the receiving antenna of the FMCW radar, and the part of the once reflected signal that is not received is reflected by the receiving antenna, and after being reflected to the target to be measured again, the signal reflected twice by the target to be measured is received by the receiving antenna again. If the transmission power is strong enough, there will be multiple reflections (for example, three-time reflection signal and four-time reflection signal, etc.). Since the FMCW radar is close to the target to be measured, the gain of the received once reflected signal (the real received signal) is less than the gain of the second or multiple reflection signal, which will cause the amplitude of the second or multiple reflection signal to be higher than the received signal, and the signal with the largest amplitude is used for calculation when calculating the distance. Taking the second or multiple reflection signal to calculate the distance information will cause the distance to be measured incorrectly, causing a blind spot for radar measurement and affecting the detection reliability of the radar.

[0039] In order to solve the above problems, an embodiment of the present application provides a distance measurement method applied to an FMCW radar, by determining an echo spectrum corresponding to the radar echo signal based on the radar echo signal; determining N echo reflection peaks corresponding to the echo spectrum based on the echo spectrum; and determining the distance information between the target to be measured and the frequency modulated continuous wave radar based on the N echo reflection peaks, thereby obtaining the actual distance of the target to be measured, reducing the probability of distance mismeasurement caused by multiple reflections of the radar signal, reducing the probability of a radar measurement blind area, and improving the reliability of radar detection.

[0040] Combine the following Figures 1 to 14 The distance measurement method, target detection method, distance measurement device, target detection device, irrigation ditch water level testing method, material box residual material detection method, surveying method, electronic device and computer-readable storage medium mentioned in the embodiments of the present application are introduced in detail.

[0041] Exemplary distance measurement method

[0042] The distance measurement method provided in the embodiment of the present application is applied to FMCW radar, and is particularly applicable to millimeter wave FMCW radar. The millimeter wave FMCW radar uses the distance measurement method provided in the embodiment of the present application to measure the distance between a single target to be measured within the short-range radar range of the millimeter wave FMCW radar and the millimeter wave FMCW radar.

[0043] Specifically, Figure 1 FIG. 2 is a flow chart of a distance measurement method provided in an embodiment of the present application. Figure 1 As shown, the distance measurement method includes the following steps.

[0044] S101: Based on the radar echo signal, determine an echo spectrum diagram corresponding to the radar echo signal.

[0045] Specifically, the transmitting antenna of the FMCW radar sends out a radar signal (electromagnetic wave), and the radar signal reflects an echo when it touches the target to be measured. The radar receiving antenna receives the radar echo signal, and the received radar echo signal needs to be processed to provide a basis for subsequent calculations. Since the spectrum diagram can reflect the relationship between the amplitude and the frequency, based on the radar echo signal, the echo spectrum diagram corresponding to the radar echo signal is determined to provide a basis for subsequent calculations.

[0046] In an optional embodiment, based on a Fast Fourier Transform (FFT) algorithm, the radar echo signal is converted from the time domain to the frequency domain to obtain an echo spectrum diagram.

[0047] Specifically, the received radar echo signal is represented in the time domain. Through FFT transformation, the radar echo signal is transformed into the frequency domain to obtain an echo spectrum diagram.

[0048] S102: Based on the echo spectrum diagram, determine N echo reflection peaks corresponding to the echo spectrum diagram.

[0049] Specifically, for FMCW radar, the receiving antenna receives a reflected signal once, and a peak appears in the echo spectrum. Therefore, the N echo reflection peaks corresponding to the echo spectrum are determined, which provides a basis for obtaining the true distance information of the target to be measured. The echo spectrum is detected to determine the N echo reflection peaks.

[0050] In an optional embodiment, N is a positive integer greater than or equal to 3.

[0051] S103: Determine the distance information between the target to be measured and the FMCW radar based on the N echo reflection peaks.

[0052] Specifically, considering that the radar signal is ultrasonic, its speed is much faster than that of the target to be measured. Therefore, the target to be measured is considered to be in a relatively static state. Therefore, the distance of each of the multiple reflections of the radar signal emitted by the FMCW radar is equal. Accordingly, there should be a certain regularity between the N echo reflection peaks. By analyzing the regularity of the N echo reflection peaks, the distance information between the target to be measured and the frequency modulated continuous wave radar can be determined.

[0053] In the embodiment of the present application, an echo spectrum diagram corresponding to the radar echo signal is determined based on the radar echo signal; N echo reflection peaks corresponding to the echo spectrum diagram are determined based on the echo spectrum diagram; 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, so as to obtain the actual distance of the target to be measured, reduce the probability of distance mismeasurement due to multiple reflections of the radar signal, reduce the probability of radar measurement blind spots, and improve the reliability of radar detection.

[0054] Figure 2 FIG. 2 is a flow chart of a distance measurement method provided in an embodiment of the present application. Figure 2 As shown, based on the echo spectrum diagram, the step of determining N echo reflection peaks corresponding to the echo spectrum diagram includes the following steps.

[0055] S201: scanning the echo spectrum diagram step by step along the frequency axis of the coordinate axis of the echo spectrum diagram, and determining the peak exceeding the preset amplitude threshold as the echo reflection peak.

[0056] S202: Determine N echo reflection peaks.

[0057] Specifically, the coordinate axes of the echo spectrum graph have a frequency axis (generally represented by the X axis of the conventional coordinate axis) and an amplitude axis (generally represented by the Y 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 the echo spectrum graph is scanned step by step from the starting end to the end along the frequency axis of the coordinate axis of the echo spectrum graph. If a peak exceeding the preset amplitude threshold appears, it is determined as an echo reflection peak.

[0058] For example, if the value range of the horizontal axis is 0-1200Hz, the amplitude threshold of 500dBm is preset in advance, the echo spectrum diagram is scanned step by step along the horizontal axis to obtain the amplitude value of the Y axis, and the peak exceeding 500dBm is counted as 1 echo reflection peak, thereby obtaining N echo reflection peaks.

[0059] In the embodiment of the present application, by presetting an amplitude threshold in advance and gradually scanning the echo spectrum diagram along the frequency axis of the coordinate axis of the echo spectrum diagram, the peak exceeding the preset amplitude threshold is determined as the echo reflection peak, thereby achieving the purpose of obtaining N echo reflection peaks, and providing a basis for subsequently determining the distance information between the target to be measured and the frequency modulated continuous wave radar by analyzing the regularity of the N echo reflection peaks.

[0060] Figure 3 FIG. 1 is a flow chart of a distance measurement method provided by an embodiment of the present application. Figure 3As shown, the step of determining the distance information between the target to be measured and the frequency modulated continuous wave radar based on N echo reflection peaks includes the following steps.

[0061] S301: Determine the frequency spectrum coordinates corresponding to each of N echo reflection peaks.

[0062] Specifically, after obtaining N echo reflection peaks, the spectrum coordinates corresponding to each of the N echo reflection peaks are obtained based on the spectrum axis of the coordinate axis of the echo spectrum diagram (ie, the spectrum corresponding to each of the N echo reflection peaks is obtained).

[0063] S302: Determine the distance information between the target to be measured and the FMCW radar based on the frequency spectrum coordinates corresponding to the N echo reflection peaks.

[0064] Specifically, the distance traveled by each of the multiple reflections of the radar signal emitted by the FMCW radar is equal. Accordingly, there should be a certain regularity between the N echo reflection peaks. The regularity between the N echo reflection peaks is also reflected in the frequency spectrum coordinates corresponding to the N echo reflection peaks. By analyzing the frequency spectrum coordinates corresponding to the N echo reflection peaks, the distance information between the target to be measured and the frequency modulated continuous wave radar can be determined.

[0065] In the embodiment of the present application, on the spectrum axis of the coordinate axis of the echo spectrum diagram, the spectrum coordinates corresponding to each of the N echo reflection peaks are obtained, and by analyzing the spectrum coordinates corresponding to each of the N echo reflection peaks, the regularity between the N echo reflection peaks is obtained, and the analyzed regularity is combined with the characteristic that the distance of each of the multiple reflections of the radar signal is equal to determine the distance information between the target to be measured and the frequency modulated continuous wave radar.

[0066] Figure 4 FIG. 1 is a flow chart of a distance measurement method provided by an embodiment of the present application. Figure 4 As shown, based on the frequency spectrum coordinates corresponding to each of the N echo reflection peaks, the step of determining the distance information between the target to be measured and the frequency modulated continuous wave radar includes the following steps.

[0067] S401: For N echo reflection peaks, based on the spectrum coordinates corresponding to the M+1th echo reflection peak and the spectrum coordinates corresponding to the Mth echo reflection peak, determine the spectrum coordinate difference corresponding to the Mth echo reflection peak to determine N-1 spectrum coordinate differences corresponding to the N echo reflection peaks.

[0068] Exemplarily, M is a positive integer less than or equal to N-1.

[0069] Specifically, the spectrum coordinates corresponding to the previous echo reflection peak are subtracted from the spectrum coordinates corresponding to the next echo reflection peak to obtain a spectrum coordinate difference. For N echo reflection peaks, the subtraction process is repeated to obtain N-1 spectrum coordinate differences corresponding to the N echo reflection peaks.

[0070] S402: If the absolute value of the difference between each two adjacent spectrum coordinate differences among the N-1 spectrum coordinate differences is within a first threshold, distance information is determined based on the N-1 spectrum coordinate differences and the sampling frequency corresponding to the echo spectrogram.

[0071] Specifically, N-1 spectrum coordinate differences are compared. If the absolute value of the difference between each two adjacent spectrum coordinate differences in the N-1 spectrum coordinate differences is within the first threshold (i.e., the N-1 spectrum coordinate differences are all similar), it indicates that the echo reflection peaks after the first echo reflection peak are all formed by multiple reflections. Since the distance of each of the multiple reflections is equal, theoretically, the N-1 spectrum coordinate differences should also be equal, and the distance corresponding to this theoretically equal spectrum coordinate difference is the distance information between the target to be measured and the frequency modulated continuous wave radar. The distance corresponding to this theoretically equal spectrum coordinate difference needs to be determined based on the sampling frequency corresponding to the N-1 spectrum coordinate differences and the echo spectrum diagram (i.e., the sampling frequency of the FMCW radar).

[0072] In the embodiment of the present application, for N echo reflection peaks, the spectrum coordinates corresponding to the previous echo reflection peak are subtracted from the spectrum coordinates corresponding to the next echo reflection peak to obtain N-1 spectrum coordinate differences corresponding to the N echo reflection peaks, and the N-1 spectrum coordinate differences are compared. If the N-1 spectrum coordinate differences are similar, the distance information between the target to be measured and the FMCW radar is obtained based on the N-1 spectrum coordinate differences and the sampling frequency corresponding to the echo spectrum diagram. The distance information is obtained by the above steps, and the probability of mistaking the secondary or multiple reflection signals for the received signals and obtaining the wrong distance information is reduced, thereby reducing the probability of mismeasurement of the distance due to multiple reflections of the radar signal, reducing the probability of the radar measurement blind area, and improving the reliability of radar detection.

[0073] In an optional embodiment, if Figure 4 As shown, the step of determining the distance information between the target to be measured and the FMCW radar based on the frequency spectrum coordinates corresponding to each of the N echo reflection peaks also includes the following steps.

[0074] S403: If the absolute value of the difference between each two adjacent spectrum coordinate differences among the N-1 spectrum coordinate differences is not within the first threshold, determine the distance information based on the spectrum 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.

[0075] Specifically, N-1 spectrum coordinate differences are compared. If the absolute value of the difference between each two adjacent spectrum coordinate differences in the N-1 spectrum coordinate differences is not within the first threshold (that is, the N-1 spectrum coordinate differences are relatively different), it indicates that after the signal transmitted by the FMCW radar is transmitted to the target to be measured, no regular multiple reflections are formed, and the radar echo signal received by the radar receiving antenna contains an interference signal. At this time, the distance is calculated based on the spectrum coordinates corresponding to the primary reflection signal received by the radar receiving antenna (that is, the spectrum coordinates corresponding to the echo reflection peak closest to the coordinate origin of the coordinate axis among the N echo reflection peaks).

[0076] Specifically, the first echo reflection time (i.e., the time taken for the radar signal to be first transmitted to the target to be measured and first reflected from the target to be measured back to the radar receiving antenna) is determined by using the spectrum 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. 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).

[0077] Exemplarily, the first echo reflection time is multiplied by the speed of light and divided by 2 to determine the distance information.

[0078] In the embodiment of the present application, taking into account the situation where there are no regular multiple reflections, the frequency spectrum coordinates and sampling frequency corresponding to the primary reflection signal received by the radar receiving antenna are calculated to obtain the distance information between the target to be measured and the frequency modulated continuous wave radar.

[0079] Figure 4a FIG. 1 is a flow chart of a distance measurement method provided by an embodiment of the present application. Figure 4a As shown, based on the frequency spectrum coordinates corresponding to each of the N echo reflection peaks, the step of determining the distance information between the target to be measured and the frequency modulated continuous wave radar includes the following steps.

[0080] S4021: Based on N-1 spectrum coordinate differences, determine the calculated spectrum coordinate differences corresponding to the N-1 spectrum coordinate differences.

[0081] Specifically, although theoretically, the N-1 spectrum coordinate differences should be equal, in reality the N-1 spectrum coordinate differences may be slightly different. Therefore, when the absolute value of the difference between each two adjacent spectrum coordinate differences in the N-1 spectrum coordinate differences is within the first threshold, it is necessary to determine the computational spectrum coordinate differences corresponding to the N-1 spectrum coordinate differences based on the N-1 spectrum coordinate differences, and obtain computational spectrum coordinates that are equivalent to the theoretically equal spectrum coordinate differences. The computational spectrum coordinates are used for calculations to provide a basis for obtaining the distance information between the target to be measured and the frequency modulated continuous wave radar.

[0082] S4022: Determine a single echo reflection time based on the calculated spectrum coordinate difference and the sampling frequency.

[0083] S4023: Determine distance information based on the single echo reflection time and the signal transmission speed of the FMCW radar.

[0084] Specifically, the single echo reflection time is the time it takes for one echo reflection process to occur among N echo reflections (that is, the process in which the radar signal is transmitted to the target to be measured and reflected from the target to be measured back to the radar receiving antenna). By calculating the single echo reflection time and the signal transmission speed of the FMCW radar (generally considered to be the speed of light), the distance information between the target to be measured and the frequency modulated continuous wave radar is obtained.

[0085] Exemplarily, the single echo reflection time and the speed of light are multiplied and divided by 2 to determine the distance information.

[0086] In an embodiment of the present application, an operational spectrum coordinate difference corresponding to N-1 spectrum coordinate differences is determined based on N-1 spectrum coordinate differences, and the obtained operational spectrum coordinate difference and the sampling frequency are substituted into a preset calculation formula to obtain the distance information between the target to be measured and the frequency modulated continuous wave radar, thereby achieving the purpose of determining the distance information between the target to be measured and the frequency modulated continuous wave radar based on the spectrum coordinates corresponding to each of the N echo reflection peaks.

[0087] In an optional embodiment, considering that the absolute value of the difference between each two adjacent spectrum coordinate differences among the N-1 spectrum coordinate differences is within the first threshold, the difference between the N-1 spectrum coordinate differences will not be particularly large. Therefore, any one of the N-1 spectrum coordinate differences is selected as the computational spectrum coordinate difference, and the computational spectrum coordinate difference and the sampling frequency are operated to obtain the distance information between the target to be measured and the frequency modulated continuous wave radar.

[0088] In a preferred embodiment, the average value of the N-1 spectrum coordinate differences is obtained by averaging the N-1 spectrum coordinate differences, and the average value of the N-1 spectrum coordinate differences is used as the calculated spectrum coordinate difference. The calculated spectrum coordinate difference and the sampling frequency are calculated to obtain the distance information between the target to be measured and the frequency modulated continuous wave radar.

[0089] In another preferred embodiment, based on the hardware parameters of the frequency modulated continuous wave radar, the preset weights corresponding to the N-1 spectrum coordinate differences are determined, and based on the preset weights corresponding to the N-1 spectrum coordinate differences, the N-1 spectrum coordinate differences are weighted to obtain the weighted values ​​corresponding to the N-1 spectrum coordinate differences, and the weighted values ​​corresponding to the N-1 spectrum coordinate differences are used as the calculated spectrum coordinate differences, and the calculated spectrum coordinate differences and the sampling frequency are calculated to obtain the distance information between the target to be measured and the frequency modulated continuous wave radar.

[0090] 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 signals, and then affecting the N-1 spectrum coordinate differences. Therefore, it is necessary to determine the preset weights corresponding to the N-1 spectrum coordinate differences based on the hardware parameters of the frequency modulated continuous wave radar to obtain more accurate calculated spectrum coordinate differences.

[0091] For example, due to the influence of the filter parameters, a portion of the N echo reflection peaks that are relatively early in time (i.e., several echo reflection peaks that are relatively close to the coordinate origin of the coordinate axis in the echo spectrum diagram) may be suppressed, resulting in a portion of the N-1 spectrum coordinate differences that are relatively early (i.e., several spectrum coordinate differences that are relatively close to the coordinate origin of the coordinate axis) being smaller. In order to obtain more accurate calculated spectrum coordinate differences, the weight of another portion of the N-1 spectrum coordinate differences that are relatively late is made greater than the weight of a portion of the spectrum coordinate differences that are relatively early.

[0092] Exemplary Object Detection Methods

[0093] The target detection method provided in the embodiment of the present application is applied to FMCW radar, and is particularly suitable for millimeter wave FMCW radar to perform target detection on a single target to be detected within the range of a short-range radar.

[0094] Figure 5 FIG. 1 is a flow chart of a target detection method provided by an embodiment of the present application. Figure 5 As shown, the target detection method includes the following steps.

[0095] S501: transmitting a radar signal to a target to be detected by using a frequency modulated continuous wave radar.

[0096] Specifically, a radar signal is transmitted to a single target to be detected within the short-range radar range of the FMCW radar.

[0097] S502: Receive the radar echo signal reflected by the target to be measured.

[0098] Specifically, a radar signal is sent to a target to be measured, and the target to be measured reflects the radar signal (ie, a radar echo signal).

[0099] S503: Based on the distance measurement method provided by any of the above embodiments, the radar echo signal is processed to obtain the distance information between the target to be measured and the FMCW radar.

[0100] 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 frequency modulated continuous wave radar.

[0101] S504: Determine the position information corresponding to the target to be measured based on the distance information between the target to be measured and the FMCW radar and the position information of the FMCW radar.

[0102] Specifically, the position information of the FMCW radar includes the 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 azimuth between the target to be measured and the FMCW 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 between the target to be measured and the FMCW radar.

[0103] In an embodiment of the present application, the radar echo signal is processed by the distance measurement method provided by any of the above embodiments to obtain the distance information between the target to be measured and the frequency modulated continuous wave radar, and based on the distance information between the target to be measured and the frequency modulated continuous wave radar and the position information of the frequency modulated continuous wave radar, the positioning information of the object to be measured is obtained to achieve the purpose of real-time positioning of the target to be measured.

[0104] It should be noted that the targets to be measured are not the same for different FMCW radar application scenarios. For example, when FMCW radar is applied to irrigation ditches, the target to be measured is the liquid level in the irrigation ditches; when FMCW radar is applied to unmanned vehicle-mounted material boxes or unmanned aerial vehicle-mounted material boxes, the target to be measured is the material in the vehicle-mounted material boxes; when FMCW radar is applied to exploration drones or exploration unmanned vehicles, the target to be measured is the object to be mapped. FMCW radar may be, but is not limited to, the above application scenarios, and accordingly, the target to be measured may be, but is not limited to, the above objects.

[0105] Exemplary irrigation ditch water level testing method

[0106] The irrigation ditch water level test method provided in the embodiment of the present application is applied to the FMCW radar. The FMCW radar is arranged directly above the irrigation ditch, and the antenna of the FMCW radar faces the water surface of the irrigation ditch.

[0107] Figure 6 FIG. 1 is a flow chart of a method for testing the water level of an irrigation ditch provided in an embodiment of the present application. Figure 6 As shown, the water level testing method of the irrigation ditch includes the following steps.

[0108] S601: Transmit radar signals to irrigation ditches via frequency modulated continuous wave radar.

[0109] S602: Receive radar echo signals reflected from the irrigation ditch.

[0110] S603: Based on the distance measurement method provided by any of the above embodiments, the radar echo signal is processed to obtain the distance information between the liquid level of the irrigation ditch and the FMCW radar.

[0111] S604: Determine water level information corresponding to the irrigation ditch based on distance information between the liquid surface of the irrigation ditch and the FMCW radar.

[0112] Specifically, the FMCW radar disposed directly above the irrigation ditch transmits a radar signal to the irrigation ditch and receives a radar echo signal reflected from the irrigation ditch. The radar echo signal is processed by the distance measurement method provided by any of the above embodiments to obtain accurate distance information between the liquid level of the irrigation ditch and the frequency modulated continuous wave radar. According to the preset height of the radar and the distance information between the liquid level of the irrigation ditch and the frequency modulated continuous wave radar, the water level information corresponding to the irrigation ditch is obtained.

[0113] 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 wetness of the irrigation ditch in real time and achieve the purpose of reasonable irrigation.

[0114] Exemplary method for detecting remaining material in a material box

[0115] The residual material detection method of the material box provided in the embodiment of the present application is applied to the FMCW radar. The FMCW radar is arranged on an unmanned vehicle or an unmanned aircraft. For example, when the FMCW radar is arranged on an unmanned vehicle, the FMCW radar is arranged at one end of the material box away from the base of the unmanned vehicle (i.e., the top of the material box), and the antenna of the FMCW radar faces the material in the vehicle-mounted material box.

[0116] Figure 7 FIG. 1 is a flow chart of a method for detecting residual material in a material box provided in an embodiment of the present application. Figure 7 As shown, the method for detecting the remaining amount of medicine in the material box includes the following steps.

[0117] S701: A radar signal is transmitted to the bottom of the material box through a frequency modulated continuous wave radar.

[0118] Specifically, the material carried in the material box can be liquid, such as pesticides, or granular matter, such as seeds or fertilizers.

[0119] S702: Receive the reflected radar echo signal.

[0120] S703: Based on the distance measurement method provided in any of the above embodiments, the radar echo signal is processed to obtain the distance information between the reflection surface in the material box that reflects the radar echo signal and the FMCW radar.

[0121] S704: Determine the material level information of the material box based on the distance information between the reflecting surface and the FMCW radar.

[0122] S705: Based on the material level information, determine the remaining amount of material in the material box.

[0123] Specifically, the FMCW radar arranged on the top of the material box transmits a radar signal to the bottom of the material box and receives a reflected radar echo signal. The radar echo signal is processed by the distance measurement method provided by any of the above embodiments to obtain the distance information between the reflecting surface in the material box that reflects the radar echo signal and the frequency modulated continuous wave radar. The material level information is obtained according to the radar position information and the distance information between the reflecting surface and the frequency modulated continuous wave radar. Based on the material level information and the volume of the material box, the remaining amount of material in the material box is obtained.

[0124] In the embodiment of the present application, through the above steps, the remaining amount of material in the material box is obtained in real time, so as to monitor the remaining amount of material and achieve the purpose of timely replenishing the material.

[0125] Exemplary Mapping Methods

[0126] Figure 8 FIG. 1 is a flow chart of a surveying and mapping method provided by an embodiment of the present application. Figure 8 As shown, the surveying and mapping method includes the following steps.

[0127] S801: transmitting a radar signal to the object to be surveyed by means of a frequency modulated continuous wave radar.

[0128] Specifically, the objects to be mapped include, but are not limited to, plants, ground, buildings, and other obstacles. The FMCW radar can be set on an exploration drone or an exploration unmanned vehicle.

[0129] S802: Receive the radar echo signal reflected by the object to be surveyed.

[0130] S803: Based on the distance measurement method provided by any of the above embodiments, the radar echo signal is processed to obtain the distance information between the object to be measured and the FMCW radar.

[0131] S804: Determine surveying result data corresponding to the object to be surveyed based on the distance information between the object to be surveyed and the FMCW radar.

[0132] Specifically, taking the FMCW radar installed on the exploration UAV as an example, a radar signal is transmitted to the object to be surveyed, and a radar echo signal returned by the object to be surveyed is received. The radar echo signal is processed by the distance measurement method provided by any of the above embodiments to obtain the distance information between the object to be surveyed and the frequency modulated continuous wave radar. According to the flight altitude of the exploration UAV, the relative height of the radar to the UAV, and the distance information between the object to be surveyed and the frequency modulated continuous wave radar obtained at multiple positions, the surveying result data corresponding to the object to be surveyed is obtained to obtain the operating environment information of the exploration UAV.

[0133] 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, so as to achieve the purpose of obtaining the working environment information based on the surveying and mapping result data to better assist the work.

[0134] Exemplary distance measuring device

[0135] The distance measurement method provided in the embodiment of the present application is applied to FMCW radar, and is particularly applicable to millimeter wave FMCW radar. The millimeter wave FMCW radar uses the distance measurement device provided in the embodiment of the present application to measure the distance between a single target to be measured within the short-range radar range of the millimeter wave FMCW radar and the millimeter wave FMCW radar.

[0136] Fig. 9 FIG. 1 is a schematic diagram of the structure of a distance measurement device provided by an embodiment of the present application. Fig. 9 As shown, the distance measurement device 100 includes a first determination module 101 , a second determination module 102 and a third determination module 103 .

[0137] The first determination module 101 is configured to determine an echo spectrum corresponding to the radar echo signal based on the radar echo signal. The second determination module 102 is configured to determine N echo reflection peaks corresponding to the echo spectrum based on the echo spectrum, where N is a positive integer greater than or equal to 3. The third determination module 103 is configured to determine the distance information between the target to be measured and the frequency modulated continuous wave radar based on the N echo reflection peaks.

[0138] The distance measurement device provided in the embodiment of the present application is applied to a frequency modulated continuous wave radar, by determining an echo spectrum diagram corresponding to the radar echo signal based on the radar echo signal; determining N echo reflection peaks corresponding to the echo spectrum diagram based on the echo spectrum diagram; and determining the distance information between the target to be measured and the frequency modulated continuous wave radar based on the N echo reflection peaks, thereby obtaining the actual distance of the target to be measured, reducing the probability of distance mismeasurement caused by multiple reflections of the radar signal, reducing the probability of a radar measurement blind area, and improving the reliability of radar detection.

[0139] In one embodiment, the second determination module 102 is further configured to scan the echo spectrum diagram step by step along the frequency axis of the coordinate axis of the echo spectrum diagram, determine the peak exceeding a preset amplitude threshold as the echo reflection peak, and determine N echo reflection peaks.

[0140] Fig.10 FIG. 2 is a schematic diagram showing the structure of a third determination module provided in an embodiment of the present application. Fig. 9 As shown, the third determining module 103 further includes: a first determining unit 1031 and a second determining unit 1032 .

[0141] The first determination unit 1031 is configured to determine the frequency spectrum coordinates corresponding to each of the N echo reflection peaks. The second determination unit 1032 is configured to determine the distance information between the target to be measured and the FMCW radar based on the frequency spectrum coordinates corresponding to each of the N echo reflection peaks.

[0142] Fig.11 FIG. 2 is a schematic diagram of the structure of a second determination module provided in an embodiment of the present application. Fig.11 As shown, the second determination unit 1032 further includes: a spectrum coordinate difference determination subunit 10321 and a first distance information determination subunit 10322 .

[0143] The spectrum coordinate difference determination subunit 10321 is configured to, for N echo reflection peaks, determine the spectrum coordinate difference corresponding to the Mth echo reflection peak based on the spectrum coordinate corresponding to the M+1th echo reflection peak and the spectrum coordinate corresponding to the Mth echo reflection peak, so as to determine N-1 spectrum 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 determine the distance information based on the N-1 spectrum coordinate differences and the sampling frequency corresponding to the echo spectrum diagram if the absolute value of the difference between each adjacent two spectrum coordinate differences in the N-1 spectrum coordinate differences is within a first threshold.

[0144] In one embodiment, Fig.11 As shown, the second determination unit 1032 further includes: a second distance information determination subunit 10323. The second distance information determination subunit 10323 is configured to determine the distance information based on the spectrum 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 if the absolute value of the difference between each two adjacent spectrum coordinate differences in the N-1 spectrum coordinate differences is not within the first threshold.

[0145] Fig.11a FIG. 2 is a schematic diagram of the structure of a first distance information determination subunit provided in an embodiment of the present application. Fig.11aAs shown, the first distance information determining subunit 10322 further includes: a first determining subunit 103221 , a second determining subunit 103222 , and a third determining subunit 103223 .

[0146] The first determination subunit 103221 is configured to determine the calculated spectrum coordinate difference corresponding to the N-1 spectrum coordinate difference based on the N-1 spectrum coordinate differences. The second determination subunit 103222 is configured to determine the single echo reflection time based on the calculated spectrum 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 frequency modulated continuous wave radar.

[0147] In an optional embodiment, the first determining subunit 103221 is further configured to select any one of the N-1 spectrum coordinate differences as the calculated spectrum coordinate difference.

[0148] In a preferred embodiment, the first determining subunit 103221 is further configured to determine an average value of N-1 frequency spectrum coordinate differences, and use the average value as the calculated frequency spectrum coordinate difference.

[0149] In another preferred embodiment, the first determination subunit 103221 is further configured to determine the preset weights corresponding to the N-1 spectrum coordinate differences based on the hardware parameters of the frequency modulated continuous wave radar, and perform weighted operations on the N-1 spectrum coordinate differences based on the preset weights corresponding to the N-1 spectrum coordinate differences to obtain the calculated spectrum coordinate differences.

[0150] In one embodiment, the first determination module 101 is further configured to convert the radar echo signal from the time domain to the frequency domain based on a fast Fourier transform algorithm to obtain an echo spectrum diagram.

[0151] The specific functions and operations of the other modules in the above distance measurement device are already in Figures 1 to 4a The distance measurement method described in detail is described in detail, so its repeated description will be omitted here.

[0152] Exemplary object detection apparatus

[0153] The target detection device provided in the embodiment of the present application is applied to FMCW radar, and is particularly suitable for millimeter wave FMCW radar to perform target detection on a single target to be detected within the range of a short-range radar.

[0154] Fig.12 FIG. 1 is a schematic diagram of the structure of a target detection device provided by an embodiment of the present application. Fig.12As shown, the target detection device 200 includes: a transmitting module 201, a receiving module 202, a processing module 203 and a position information determining module 204.

[0155] The transmitting module 201 is configured to transmit a radar signal 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 process the radar echo signal based on the distance measurement method provided in any of the above embodiments to obtain the distance information between the target to be measured and the frequency modulated continuous wave radar. The position information determination module 204 is configured to determine the position information corresponding to the target to be measured based on the distance information and the position information of the frequency modulated continuous wave radar.

[0156] The specific functions and operations of other modules in the above target detection device are already in Figure 5 The target detection method described in detail is described in detail, so its repeated description will be omitted here.

[0157] Considering that FMCW radar is increasingly widely used, there are many items that need to be tested for radar performance measurement, and its antenna pattern plays an extremely important role in radar performance. However, measuring the pattern requires building a professional test environment, which is very expensive.

[0158] Exemplary radar measurement device

[0159] Other embodiments of the present application further provide a radar measuring device for obtaining the antenna pattern of a radar, which is suitable for measuring the FMCW radar provided by any of the above embodiments to obtain the antenna pattern of the FMCW radar.

[0160] The antenna pattern, also known as the radiation pattern or far-field pattern, refers to a graph showing how the relative field strength (normalized modulus) of the radiation field changes with direction at a certain distance from the radar antenna. It is usually represented by two mutually perpendicular plane patterns passing through the direction of maximum radiation of the radar antenna.

[0161] The radar measurement device can be set up in an open test field or in a test field where there are no reflective objects such as cables or branches in the sky.

[0162] Fig.13 FIG. 1 is a schematic diagram of the structure of a radar measuring device provided in one embodiment of the present application. Fig.13 As shown, the radar measuring device 1300 includes a wave-absorbing semicircular outer frame 1301 , a movable reflecting component 1302 , and a processor 1303 .

[0163] The wave-absorbing semicircular outer frame 1301 can prevent the radar signal from scattering; the radar 1304 to be tested is arranged at the center of the wave-absorbing semicircular outer frame 1301, and the antenna surface of the radar 1304 to be tested is directly opposite to the center of the arc. The movable reflective component 1302 is arranged on the inner side of the wave-absorbing semicircular outer frame 1301 and slides along the wave-absorbing semicircular outer frame 1301, and is used to reflect the radar signal emitted by the radar 1304 to be tested. The processor 1303 is connected to the radar 1304 to control the radar 1304 to transmit the intermediate frequency signal, and generates the antenna radiation pattern based on the echo signals collected by the movable reflective component 1302 at different positions of the wave-absorbing semicircular outer frame 1301.

[0164] Specifically, the processor 1303 controls the antenna of the radar 1304 to be tested to transmit the intermediate frequency signal, and the movable reflecting component 1302 slides along the wave-absorbing semicircular outer frame 1301. The moving speed of the movable reflecting component 1302 is adapted to the transmission frequency of the radar signal transmitted by the radar 1304 to be tested, so that the movable reflecting component 1302 can receive the radar signal transmitted by the radar 1304 to be tested when it is at different positions of the wave-absorbing semicircular outer frame 1301.

[0165] Since the wave-absorbing semicircular outer frame 1301 is semicircular in shape, the relative distance between the mobile reflective component 1302 and the radar to be tested 1304 is consistent (all radius) during the test process. After the radar to be tested 1304 transmits the radar signal, it is reflected by the mobile reflective component 1302, and the echo signal is received by the radar to be tested and transmitted to the processor 1303. Since the gain in the normal direction of the antenna is the largest, when the mobile reflective component 1302 is at the 90° position of the arc, the intermediate frequency signal amplitude is the strongest. When the mobile reflective component 1302 slides to both sides, the intermediate frequency signal amplitude will change, and this change will be transmitted to the processor 1303. The processor reversely infers the RF end power by judging the strength of the intermediate frequency signal amplitude, thereby obtaining the antenna radiation pattern.

[0166] In one embodiment, the wave-absorbing semicircular outer frame 1301 is made of wave-absorbing material, or a light-weight outer frame is prepared and wrapped with wave-absorbing material.

[0167] In one embodiment, the movable reflective component 1302 may be a triangle in shape.

[0168] The radar monitoring device provided in the embodiments 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.

[0169] Exemplary Electronic Devices

[0170] Fig.14 FIG. 1 is a schematic diagram of the structure of an electronic device provided by an embodiment of the present application. Fig.14As shown, the electronic device 300 includes one or more processors 310 and a memory 320 .

[0171] The processor 310 may be a central processing unit (CPU) or other forms of processing units having data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device 300 to perform desired functions.

[0172] The memory 320 may include one or more computer program products, and the computer program products 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 (cache), etc. The non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. 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 each embodiment of the present application described above, or the target detection method of each embodiment, or the water level test method of the irrigation ditch of the embodiment, or the remaining material detection method of the material box of the embodiment, or the surveying and mapping method of the embodiment and / or other desired functions.

[0173] In one example, the electronic device 300 may further include: an input device 330 and an output device 340 , and these components are interconnected via a bus system and / or other forms of connection mechanisms (not shown).

[0174] Of course, to simplify, Fig.14 Only some of the components related to the present application in the electronic device 300 are shown, and components such as a bus, an input / output interface, etc. are omitted. In addition, according to specific application situations, the electronic device 300 may also include any other appropriate components.

[0175] Exemplary computer program products and computer-readable storage media

[0176] In addition to the above-mentioned methods and devices, an embodiment of the present application may also be a computer program product, which includes computer program instructions, which, when executed by a processor, enable the processor to execute the steps of the distance measurement method provided according to the various embodiments of the present application described in the above "Exemplary Distance Measurement Method" section of this specification, or execute the steps of the target detection method provided according to the various embodiments of the present application described in the above "Exemplary Target Detection Method" section of this specification, or execute the steps of the irrigation ditch water level testing method provided according to the various embodiments of the present application described in the above "Exemplary Irrigation Ditch Water Level Testing Method" section of this specification, or execute the steps of the remaining material detection method for the material box provided according to the various embodiments of the present application described in the above "Exemplary Material Box Remaining Material Detection Method" section of this specification, or execute the steps of the surveying and mapping method provided according to the various embodiments of the present application described in the above "Exemplary Surveying and Mapping Method" section of this specification.

[0177] The computer program product may be written in any combination of one or more programming languages ​​to write program codes for performing the operations of the embodiments of the present application, including object-oriented programming languages, such as Java, C++, etc., and also conventional step-by-step programming languages, such as "C" language or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, as an independent software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0178] In addition, an embodiment of the present application may also be a computer-readable storage medium having computer program instructions stored thereon, and when the computer program instructions are executed by a processor, the processor executes the steps of the distance measurement method provided according to the various embodiments of the present application described in the above “Exemplary Distance Measurement Method” section of this specification, or executes the steps of the target detection method provided according to the various embodiments of the present application described in the above “Exemplary Target Detection Method” section of this specification, or executes the steps of the irrigation ditch water level testing method provided according to the various embodiments of the present application described in the above “Exemplary Irrigation Ditch Water Level Testing Method” section of this specification, or executes the steps of the remaining material detection method for the material box provided according to the various embodiments of the present application described in the above “Exemplary Material Box Remaining Material Detection Method” section of this specification, or executes the steps of the surveying and mapping method provided according to the various embodiments of the present application described in the above “Exemplary Surveying and Mapping Method” section of this specification.

[0179] The computer readable storage medium can adopt any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium can include, for example, but is not limited to, a system, device or device of electricity, magnetism, light, electromagnetic, infrared, or semiconductor, or any combination of the above. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0180] It should be noted that the above examples are only specific embodiments of the present application. Obviously, the present application is not limited to the above examples, and there are many similar variations. All variations directly derived or associated from the contents disclosed in the present application by those skilled in the art should fall within the protection scope of the present application.

[0181] It should be understood that the qualifiers such as first and second mentioned in the embodiments of the present application are only used to more clearly describe the technical solutions of the embodiments of the present application and cannot be used to limit the scope of protection of the present application.

[0182] The above are only preferred embodiments of the present application and are not intended to limit the protection scope of the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A distance measurement method, characterized in that: The method is used to measure the distance between a frequency modulated continuous wave radar and a target to be measured within the signal range of the frequency modulated continuous wave radar, and comprises: Based on the radar echo signal, determining an echo spectrum diagram corresponding to the radar echo signal; Based on the echo spectrum diagram, determine N echo reflection peaks corresponding to the echo spectrum diagram, where N is a positive integer greater than or equal to 3; Based on the N echo reflection peaks, determining the distance information between the target to be measured and the frequency modulated continuous wave radar; Wherein, determining the distance information between the target to be measured and the frequency modulated continuous wave radar based on the N echo reflection peaks includes: Determine the frequency spectrum coordinates corresponding to each of the N echo reflection peaks; Determining the distance information between the target to be measured and the frequency modulated continuous wave radar based on the frequency spectrum coordinates corresponding to each of the N echo reflection peaks; Wherein, determining the distance information between the target to be measured and the frequency modulated continuous wave radar based on the frequency spectrum coordinates corresponding to each of the N echo reflection peaks includes: For the N echo reflection peaks, based on the frequency spectrum coordinates corresponding to the M+1th echo reflection peak and the frequency spectrum coordinates corresponding to the Mth echo reflection peak, determine the frequency spectrum coordinate difference corresponding to the Mth echo reflection peak to determine N-1 frequency spectrum 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 two adjacent spectrum coordinate differences among the N-1 spectrum coordinate differences is within a first threshold, the distance information is determined based on the N-1 spectrum coordinate differences and a sampling frequency corresponding to the echo spectrogram.

2. The distance measurement method according to claim 1, characterized in that: The determining, based on the echo spectrum diagram, N echo reflection peaks corresponding to the echo spectrum diagram comprises: The echo spectrum diagram is scanned step by step along the frequency axis of the coordinate axis of the echo spectrum diagram, and the peak exceeding a preset amplitude threshold is determined as the echo reflection peak, so as to determine the N echo reflection peaks.

3. The distance measurement method according to claim 1, characterized in that: The determining the distance information based on the N-1 frequency spectrum coordinate differences and the sampling frequency corresponding to the echo spectrum diagram includes: Based on the N-1 spectrum coordinate differences, determining a calculated spectrum coordinate difference corresponding to the N-1 spectrum coordinate differences; Determining a single echo reflection time based on the calculated spectrum 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 frequency modulated continuous wave radar.

4. The distance measurement method according to claim 3, characterized in that: The determining, based on the N-1 spectrum coordinate differences, the calculated spectrum coordinate differences corresponding to the N-1 spectrum coordinate differences comprises: Selecting any one of the N-1 spectrum coordinate differences as the calculated spectrum coordinate difference; or, Determine an average value of the N-1 frequency spectrum coordinate differences, and use the average value as the calculated frequency spectrum coordinate difference; or, Based on the hardware parameters of the frequency modulated continuous wave radar, the preset weights corresponding to the N-1 spectrum coordinate differences are determined, and based on the preset weights corresponding to the N-1 spectrum coordinate differences, the N-1 spectrum coordinate differences are weightedly calculated to obtain the calculated spectrum coordinate differences.

5. The distance measurement method according to claim 1, characterized in that: The determining of the distance information between the target to be measured and the FMCW radar based on the frequency spectrum coordinates corresponding to each of the N echo reflection peaks further includes: If the absolute value of the difference between each adjacent two spectrum coordinate differences among the N-1 spectrum coordinate differences is not within the first threshold, the distance information is determined based on the spectrum coordinates corresponding to the echo reflection peak closest to the coordinate origin of the coordinate axis among the N echo reflection peaks and the sampling frequency.

6. A target detection method, characterized in that: The method comprises: Transmitting radar signals to the target to be detected by frequency modulated continuous wave radar; Receiving a radar echo signal reflected by the target to be measured; Based on the distance measurement method according to any one of claims 1 to 5, the radar echo signal is processed to obtain the distance information between the target to be measured and the frequency modulated continuous wave radar; Based on the distance information and the position information of the FMCW radar, the position information corresponding to the target to be detected is determined.

7. A method for testing the water level of an irrigation ditch, characterized in that: The method comprises: transmitting radar signals to irrigation ditches by means of frequency modulated continuous wave radar; receiving a radar echo signal reflected from the irrigation ditch; Based on the distance measurement method according to any one of claims 1 to 5, 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.

8. A method for detecting residual material in a material box, characterized in that: The method comprises: The radar signal is transmitted to the bottom of the material box by means of a frequency modulated continuous wave radar; Receive the reflected radar echo signal; Based on the distance measurement method according to any one of claims 1 to 5, the radar echo signal is processed to obtain the distance information between the reflection surface in the material box that reflects the radar echo signal and the frequency modulated continuous wave radar; Determining material level information of the material box based on distance information between the reflecting surface and the frequency modulated continuous wave radar; Based on the material level information, the remaining amount of material in the material box is determined.

9. A surveying and mapping method, characterized in that: The method comprises: Transmitting radar signals to the object to be surveyed by means of frequency modulated continuous wave radar; Receiving a 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 5, the radar echo signal is processed to obtain the distance information between the object to be measured and the frequency modulated 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.

10. A distance measuring device, characterized in that: The device is used to measure the distance between a frequency modulated continuous wave radar and a target to be measured within the signal range of the frequency modulated continuous wave radar, and comprises: A first determination module is configured to determine an echo spectrum diagram corresponding to the radar echo signal based on the radar echo signal; A second determination module is configured to determine N echo reflection peaks corresponding to the echo spectrum diagram based on the echo spectrum diagram, where N is a positive integer greater than or equal to 3; A third determination module is configured to determine the distance information between the target to be measured and the FMCW radar based on the N echo reflection peaks; Wherein, the third determination module further comprises: a first determination unit and a second determination unit; The first determination unit is configured to determine the frequency spectrum coordinates corresponding to each of the N echo reflection peaks; The second determination unit is configured to determine the distance information between the target to be measured and the frequency modulated continuous wave radar based on the frequency spectrum coordinates corresponding to each of the N echo reflection peaks; Wherein, the second determination unit further comprises: a spectrum coordinate difference determination subunit and a first distance information determination subunit; The spectrum coordinate difference determining subunit is configured to determine, for the N echo reflection peaks, the spectrum coordinate difference corresponding to the Mth echo reflection peak based on the spectrum coordinate corresponding to the M+1th echo reflection peak and the spectrum coordinate corresponding to the Mth echo reflection peak, so as to determine N-1 spectrum coordinate differences corresponding to the N echo reflection peaks, wherein M is a positive integer less than or equal to N-1; The first distance information determination subunit is configured to determine the distance information based on the N-1 spectral coordinate differences and the sampling frequency corresponding to the echo spectrum diagram if the absolute value of the difference between each adjacent two spectral coordinate differences among the N-1 spectral coordinate differences is within a first threshold.

11. A target detection device, characterized in that: The device comprises: A transmitting module, configured to transmit a radar signal to a target to be detected via a frequency modulated continuous wave radar; A receiving module, configured to receive a radar echo signal reflected from 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 5, to obtain distance information between the target to be measured and the frequency modulated continuous wave radar; The position information determination module is configured to determine the position information corresponding to the target to be measured based on the distance information and the position information of the frequency modulated continuous wave radar.

12. An electronic device comprising: processor; as well as A memory, in which computer program instructions are stored, and when the computer program instructions are executed by the processor, the processor is caused to perform the method according to any one of claims 1 to 9.

13. A computer-readable storage medium having computer program instructions stored thereon, wherein when the computer program instructions are executed by a processor, the processor is enabled to execute the method according to any one of claims 1 to 9.

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