JP7324859B2 - processing equipment - Google Patents

Description

The present disclosure relates to a processing device used in radar equipment.

BACKGROUND ART Conventionally, an invention related to a radar device using chirp waves is known (see Patent Document 1 below). The conventional radar device described in Patent Document 1 includes first processing means, second processing means, and velocity determination means. The first processing means uses a beat signal obtained by transmitting and receiving a preset first modulated wave a plurality of times to obtain a preset At least the velocity containing ambiguity due to phase folding is obtained within the velocity measurement range.

The second processing means uses a beat signal obtained by transmitting/receiving a preset second modulated wave, and is uniquely determined within the speed measurement range from the Doppler frequency included in the frequency component representing the target. Ask for speed at least. The speed determination means determines the measurement result of the speed represented by the resolution realized by the first processing means by comparing the calculation result by the first processing means and the calculation result by the second processing means. According to such a configuration, high-resolution speed measurement results can be obtained without speeding up the sampling of the beat signal (see claim 1, paragraphs 0007 and 0008 of the same document). .

JP 2016-003873 A

The conventional radar apparatus performs fast Fourier transform (FFT) processing on the second modulation data, which is A/D conversion data of the beat signal acquired in the second modulation period (Patent Document 1, paragraph 0022-th 0023, see FIG. 3, etc.). Also, a two-dimensional FFT is performed on the first modulation data, which is the A/D conversion data of the beat signal acquired in the first modulation period (see the same document, paragraph 0027, FIG. 3, etc.). This conventional radar device has a problem of an increase in the amount of calculation and an increase in the amount of memory used.

The present disclosure provides a processing device that can be used for signal processing of a radar device and that can reduce the amount of calculation and the amount of memory used compared to conventional ones.

One aspect of the present disclosure is a processing device for performing signal processing of a radar device that transmits and receives a first continuous wave and a second continuous wave, which are frequency-modulated continuous waves, wherein the beat frequency of the first continuous wave is 1-frequency analysis is performed to extract the peak of the power spectrum, the frequency corresponding to the peak is subjected to analysis, and the second frequency analysis is performed for the beat frequency of the second continuous wave to calculate the distance, velocity and direction of the object. It is a processing apparatus characterized by the following.

According to the above aspect of the present disclosure, it is possible to provide a processing device that can be used for signal processing of a radar device and that can reduce the amount of calculation and the amount of memory used compared to the conventional art.

1 is a functional block diagram showing an embodiment of a processing device according to the present disclosure; FIG. FIG. 2 is a flow chart showing the flow of processing of the processing apparatus of FIG. 1; An example of a frequency modulated continuous wave transmitted by radar equipment. An example of a frequency modulated continuous wave transmitted by radar equipment. FIG. 3 is an explanatory diagram of the process of setting the frequency to be analyzed and the second frequency analysis shown in FIG. 2; 4 is a graph showing the relationship between the number of discrete Fourier transform analysis peaks and the amount of computation;

Hereinafter, embodiments of a processing apparatus according to the present disclosure will be described with reference to the drawings.

Embodiment 1 FIG. 1 is a functional block diagram showing Embodiment 1 of a processing device according to the present disclosure. The processing device 11 of this embodiment is a processing device 11 for performing signal processing of the radar device 10 . An example of the configuration of the radar device 10 will first be briefly described below, and then an example of the configuration of the processing device 11 that performs signal processing of the radar device 10 will be described in detail.

(Radar Device) The radar device 10 of the present embodiment is, for example, a frequency-modulated continuous wave (FMCW) type radar device. Detects the relative velocity of an object and the direction in which the object exists. The radar device 10 includes, for example, a processing device 11 that performs signal processing, a signal transmission section 12 including a plurality of transmission antennas 12a, and a signal reception section 13 including a plurality of reception antennas 13a. Processing device 11 may be arranged outside radar device 10 , and for example, vehicle control device 20 that controls a vehicle in which radar device 10 is mounted may include processing device 11 .

The radar device 10 has the same configuration as the conventional FMCW radar device 10 . That is, the radar device 10 includes, for example, generators, couplers, mixers, and A/D converters (not shown). The generator generates a frequency modulated (FM) signal based on control signals from processor 11 . The coupler separates the FM signal input from the generator into two identical signals and outputs them to the mixer and the signal transmitter 12 .

The mixer of the radar device 10 outputs a beat frequency signal to the A/D converter based on the FM signal of the transmission wave input from the coupler and the FM signal of the reception wave input from the signal receiver 13 . The A/D converter outputs data obtained by A/D converting the beat frequency signal input from the mixer to the processing device 11, for example. Here, the data obtained by A/D converting the beat frequency signal is called "beat frequency".

(Processing Device) The processing device 11 is, for example, a microcontroller or firmware that includes an arithmetic device such as a CPU or MPU (not shown), a storage device such as a ROM or a RAM, a computer program, a timer, an input/output device, and the like. . The processing device 11 transmits a control signal to the generator of the radar device 10, and based on the beat frequency input from the A/D converter of the radar device 10, determines the distance and speed of an object around the radar device 10. Calculate the bearing.

The processing device 11 has, for example, a function F1 for controlling transmission and reception of FMCW, a function F2 for frequency analysis, and a function F3 for signal processing. Furthermore, the function F2 for frequency analysis includes a function F21 for setting the frequency to be analyzed, a function F22 for frequency analysis calculation, and a function F23 for extracting the peak of the power spectrum. These functions F1, F2, and F3 are realized, for example, by executing a program stored in a storage device by an arithmetic device in the processing device 11. FIG.

Hereinafter, each function F1, F2, F3 of the processing device 11 will be described in detail with reference to FIGS. 2 to 5. FIG. FIG. 2 is a flowchart showing the processing flow of the processing device 11 of this embodiment. 3A and 3B are graphs showing an example of FMCW transmitted from the signal transmission unit 12 of the radar device 10, with the horizontal axis representing time and the vertical axis representing frequency.

When the signal processing of the radar device 10 is started, the processing device 11 first performs the processing P1 of receiving the first continuous wave CW1. More specifically, in this process P1, the function F1 for controlling transmission and reception of FMCW of the processing device 11, for example, transmits a control signal to the generator of the radar device 10 to cause the generator to generate an FM signal. The FM signal output from the generator is input to the signal transmitting section 12 and the mixer via the coupler, and the first continuous wave CW1 as FMCW is transmitted from the transmitting antenna 12a.

The radar device 10 of the present embodiment is, for example, an FCM (First-Chirp Modulation) radar device. That is, the radar device 10 continuously transmits the frequencies of the first continuous wave CW1 and the second continuous wave CW2, which are transmission waves, while sweeping them at high speed in units of several microseconds to several tens of microseconds, for example. The method of the radar device 10 is not limited to the FCM method, and other methods can be adopted.

For example, the processing device 11 controls the signal transmission section 12 of the radar device 10 using the function F1 for controlling transmission and reception of FMCW to change the frequency deviation width Δf1 of the first continuous wave CW1 to the frequency deviation of the second continuous wave CW2. It is expanded more than the shift width Δf2. Further, in the example shown in FIG. 3A, the processing device 11 controls the signal transmission unit 12 of the radar device 10 by, for example, the function F1 that controls transmission and reception of FMCW, and sets the interval Δt2 between the second continuous waves CW2 to It is shorter than the interval Δt1 between the first continuous waves CW1.

Further, the function F1 of the processing device 11 controls, for example, the signal transmission unit 12 and the signal reception unit 13 of the radar device 10 to generate a plurality of first continuous waves CW1 and a plurality of second continuous waves CW1 as shown in FIG. 3A. CW2 are alternately transmitted and received. In other words, the processing device 11 alternately repeats the first modulation period T1 for transmitting and receiving the plurality of first continuous waves CW1 and the second modulation period T2 for transmitting and receiving the plurality of second continuous waves CW2.

Here, the number of first continuous waves CW1 included in the first modulation period T1 and the number of second continuous waves CW2 included in the second modulation period T2 are not particularly limited. Also, the order of the first modulation period T1 and the second modulation period T2 may be reversed from the example shown in FIG. 3A. The interval between the first modulation period T1 and the second modulation period T2 or the interval between the first continuous wave CW1 and the second continuous wave CW2 is preferably made as short as possible.

In addition, the function F1 of the processing device 11 controls, for example, the signal transmission unit 12 and the signal reception unit 13 of the radar device 10 to generate one first continuous wave CW1 and one second continuous wave CW1 as shown in FIG. 3B. Wave CW2 may be alternately transmitted and received. Such switching between the first continuous wave CW1 and the second continuous wave CW2 is performed, for example, by switching the switch 12s of the signal transmitting unit 12 by the function F1 for controlling transmission and reception of FMCW of the processing device 11 to switch the transmitting antenna 12a. can be done by

Alternatively, the processing device 11 may switch between the first continuous wave CW1 and the second continuous wave CW2 by changing the modulation setting of the signal transmitting unit 12 using the function F1 for controlling transmission and reception of FMCW. good. Also, the function F1 of the processing device 11 may control, for example, the signal transmission unit 12 of the radar device 10 to switch between the first transmitting antenna 12a1 and the second transmitting antenna 12a2 arranged at different positions of the radar device 10. good.

A first continuous wave CW<b>1 transmitted from the transmitting antenna 12 a of the signal transmitting section 12 is reflected by objects around the radar device 10 and received by the receiving antenna 13 a of the signal receiving section 13 . Thus, the processing P1 for receiving the first continuous wave CW1 shown in FIG. 2 is completed.

Next, the processor 11 performs a first frequency analysis P2, as shown in FIG. The signal receiver 13 of the radar device 10 outputs to the mixer an FM signal based on the first continuous wave CW1 received by the receiving antenna 13a in the process of receiving the first continuous wave CW1. The mixer of the radar device 10 generates a first The beat frequency of one continuous wave CW1 is output to the processor 11. FIG.

The processing device 11 inputs, for example, the beat frequency of the first continuous wave CW1 input from the mixer of the radar device 10 to the function F22 that performs frequency analysis calculation through the function F21 that sets the frequency to be analyzed. Here, the function F21 for setting the frequency to be analyzed does not function, and the beat frequency of the first continuous wave CW1 input from the mixer of the radar device 10 is directly output to the function F22 for frequency analysis calculation. The function F22 for frequency analysis calculation performs a first frequency analysis P2 on the beat frequency of the input first continuous wave CW1.

A first frequency analysis P2 for the beat frequency of the first continuous wave CW1 includes, for example, a Fast Fourier Transform (FFT). The first frequency analysis P2 executes, for example, two FFTs. In the first FFT of the first frequency analysis P2, frequency analysis is performed on data sampled, for example, at a sampling number Ns for each first continuous wave CW1. By this frequency analysis, a power spectrum is calculated for each distance bin, which is a frequency bin corresponding to the distance to the object. This power spectrum represents the power of the reflected wave of the first continuous wave CW1.

The second FFT of the first frequency analysis P2 performs frequency analysis for each distance bin from the power spectra of the Nc first continuous waves CW1, which are all the first continuous waves CW1 in the first modulation period T1. By this frequency analysis, a power spectrum is calculated for each velocity bin, which is a frequency bin corresponding to the velocity of the object in each distance bin. As described above, the first frequency analysis P2 shown in FIG. 2 is completed.

Next, as shown in FIG. 2, the processor 11 executes a process P3 for extracting peaks. In this process P3, the processing device 11 extracts object detection data by, for example, the function F23 for extracting the peak of the power spectrum shown in FIG. Specifically, in this process P3, the function F23 determines that the power spectrum, which is the combination of distance and velocity calculated in the first frequency analysis P2, exceeds a predetermined detection threshold value stored in the storage device. Objects are extracted as object detection data. As described above, the processing P3 for extracting the peak shown in FIG. 2 is completed.

Next, the processing device 11 executes a process P4 of receiving the second continuous wave CW2, as shown in FIG. Specifically, the processing device 11 performs, for example, the function F1 for controlling transmission/reception of FMCW shown in FIG. to transmit the second continuous wave CW2, which is FMCW, from the transmitting antenna 12a. A second continuous wave CW<b>2 transmitted from the transmitting antenna 12 a is reflected by objects around the radar device 10 and received by the receiving antenna 13 a of the signal receiving section 13 . Thus, the processing P4 for receiving the second continuous wave CW2 shown in FIG. 2 is completed.

Next, as shown in FIG. 2, the processing device 11 executes a process P5 of setting the frequency to be analyzed in the second frequency analysis P6. Specifically, in this process P5, the processing device 11 sets the analysis target frequency in the second frequency analysis P6, for example, by the function F21 for setting the analysis target frequency shown in FIG. More specifically, the processing device 11 converts the frequencies corresponding to the distance bins and velocity bins of the power spectrum extracted by the function F23 in the process P3 to the frequencies to be analyzed in the second frequency analysis P6 by the function F21 in the process P5. set as

FIG. 4 is an explanatory diagram of the process P5 for determining the frequency to be analyzed and the second frequency analysis P6 shown in FIG. In the left and right graphs of FIG. 4, the horizontal axis is distance bins and the vertical axis is speed bins. A plurality of peaks PK1, PK2, and PK3 are extracted as an object detection result as shown in the left graph of FIG.

In the example shown in FIG. 4, when the extracted peaks PK1, PK2, and PK3 are represented by the distance bin number Fri and the velocity bin number Frj, respectively, (fr2, fv4), (fr5, fv5), and (fr8, fv6). It's becoming As indicated by dot hatching in the graph on the left side of FIG. 4, in the first frequency analysis P2, frequency analysis is performed even in the region NR where the peaks PK1, PK2, and PK3 are not extracted. In the processing P5 for setting the frequency to be analyzed, the processing device 11 uses the function F21 to set the frequency of the AO to be analyzed in the second frequency analysis P6 as shown in the right graph of FIG.

More specifically, the function F21 is a combination of distance bin numbers and velocity bin numbers (fr2, fv4), (fr5, fv5), (fr8, fv6) of the peaks PK1, PK2, and PK3 shown in the left graph of FIG. The combinations (fr2′, fv4′), (fr5′, fv5′), and (fr8′, fv6′) of distance bin numbers and velocity bin numbers corresponding to It is set to the frequency of the analysis target AO of the frequency analysis P6.

Here, the function F21 of the processing device 11 corrects the frequency error caused by the time difference between the first modulation period T1 and the second modulation period T2 or between the first continuous wave CW1 and the second continuous wave CW2. The frequency of the AO to be analyzed may be set in consideration of this. Note that, as described above, the above error can be reduced.

Next, the processor 11 performs a second frequency analysis P6, as shown in FIG. The processing device 11 executes the second frequency analysis P6 by, for example, the function F22 for frequency analysis calculation shown in FIG. More specifically, as shown in FIG. 4, the function F22 performs analysis on the frequencies corresponding to the peaks PK1, PK2, and PK3 extracted from the result of the first frequency analysis P2, and analyzes the second continuous wave CW2. A second frequency analysis P6 is performed on the beat frequency.

That is, the function F22 of the processing unit 11 performs does not perform the second frequency analysis P6. Here, the second frequency analysis P6 includes, for example, a discrete Fourier transform (DFT) capable of selecting arbitrary frequencies for analysis. As a result, in the second frequency analysis P6, only the frequency of the analysis target AO is subjected to two frequency analyzes using DFT, and the power spectrum of distance and velocity is calculated.

Note that the peak of the power spectrum, which is the object detection result, is already known by the first frequency analysis P2 and the process P3 of extracting the peak. Therefore, the function F23 for extracting the peak of the power spectrum does not operate after the second frequency analysis P6 by the function F22 for frequency analysis calculation is completed. That is, the function F23 directly outputs the processing result of the second frequency analysis P6 input from the function F22 to the function F3 that performs signal processing. As described above, the processing shown in FIG. 2 by the frequency analysis function F2 of the processing device 11 ends.

After that, the processing device 11 uses the signal processing function F3 to determine the distance, velocity, and bearing of objects around the radar device 10 based on the processing result of the second frequency analysis P6 output from the frequency analysis function F2. calculate. The function F3 of the processing device 11 outputs the calculated distance, speed and direction of the object to the vehicle control device 20 and the user interface 30, for example, as the detection result of the object by the radar device 10. FIG.

The operation of the processing device 11 of this embodiment will be described below.

As described above, the processing device 11 of this embodiment is a processing device for performing signal processing of the radar device 10 that transmits and receives the first continuous wave CW1 and the second continuous wave CW2, which are frequency-modulated continuous waves. The processing device 11 of the present embodiment performs a first frequency analysis P2 on the beat frequency of the first continuous wave CW1, extracts the peak of the power spectrum, and uses the frequency corresponding to the peak as the analysis target OA for the second continuous wave CW2. A second frequency analysis P6 is performed on the beat frequency of , and the distance, velocity, and bearing of the object are calculated.

With such a configuration, the processing device 11 of this embodiment can reduce the amount of calculation and the amount of memory used compared to the conventional one. That is, the conventional radar apparatus described in Patent Document 1 executes FFT processing on the second modulated data, and further executes two-dimensional FFT on the first modulated data. On the other hand, the processing device 11 of the present embodiment performs the second frequency analysis P6 on limited frequencies corresponding to the peak of the power spectrum, which is the result of object detection by the first frequency analysis P2, as the analysis target OA.

That is, the processing device 11 of the present embodiment does not need to perform the second frequency analysis P6 at frequencies where the peak of the power spectrum, which is the object detection result obtained by the first frequency analysis P2, is not extracted. Therefore, according to the processing device 11 of the present embodiment, compared with the conventional radar device that performs two FFTs for all frequencies, not only can the amount of calculation be reduced, but also the calculation result can be stored. It is possible to greatly reduce the amount of memory used for storing.

Further, as described above, the processing device 11 of the present embodiment controls the radar device 10 to expand the frequency deviation width Δf1 of the first continuous wave CW1 more than the frequency deviation width Δf2 of the second continuous wave CW2. .

With such a configuration, the processing device 11 of the present embodiment performs frequency analysis of the beat frequency obtained by causing the radar device 10 to transmit and receive the first continuous wave CW1, thereby comparing it with the second continuous wave CW2. , the distance to objects around the radar device 10 can be detected more accurately. Further, the processing device 11 of the present embodiment analyzes the beat frequency obtained by causing the radar device 10 to transmit and receive the second continuous wave CW2, thereby comparing the beat frequency of the radar device 10 with the first continuous wave CW1. The speed of surrounding objects can be detected more accurately.

Further, as described above, the processing device 11 of the present embodiment controls the radar device 10 to alternately transmit and receive the plurality of first continuous waves CW1 and the plurality of second continuous waves CW2.

With such a configuration, the processing device 11 of the present embodiment can increase the number of data in the first frequency analysis P2 and more accurately detect the distance to objects around the radar device 10 . Also, the processing device 11 of the present embodiment can increase the number of data in the second frequency analysis P6 and detect the speed of the object around the radar device 10 more accurately.

Further, as described above, the processing device 11 of the present embodiment controls the radar device 10 to alternately transmit and receive one first continuous wave CW1 and one second continuous wave CW2.

With such a configuration, the processing device 11 of the present embodiment can shorten the time interval between the first continuous wave CW1 and the second continuous wave CW2, and based on the result of the first frequency analysis P2 The analysis target AO of the second frequency analysis P6 can be set with higher accuracy.

Further, the processing device 11 of the present embodiment controls the radar device 10 to switch between the first transmitting antenna 12a1 and the second transmitting antenna 12a2 arranged at different positions on the radar device 10 .

With such a configuration, the processing device 11 of the present embodiment virtually increases the number of antennas of the radar device 10, and makes the radar device 10 a MIMO (Multiple Input Multiple Output) type radar device that can be miniaturized. be able to. Moreover, the processing device 11 of the present embodiment can improve the detection accuracy of the direction in which an object exists by virtually increasing the number of antennas of the radar device 10 .

Moreover, in the processing device 11 of the present embodiment, the first frequency analysis P2 includes fast Fourier transform, and the second frequency analysis P6 includes discrete Fourier transform.

With such a configuration, the processing device 11 of the present embodiment can detect objects around the radar device 10 by performing frequency analysis of the entire range of the beat frequency of the first continuous wave CW1 in the first frequency analysis P2. can. Further, the processing device 11 of the present embodiment performs frequency analysis of the beat frequency of the second continuous wave CW2 in the second frequency analysis P6 with respect to the frequency corresponding to the object detected as a result of the first frequency analysis P2. , it is possible to reduce the amount of calculation and the amount of memory used.

As described above, according to the present embodiment, it is possible to provide the processing device 11 that can be used for signal processing of the radar device 10 and that can reduce the amount of calculation and the amount of memory used compared to the conventional technology. .

[Embodiment 2] Next, Embodiment 2 of the processing apparatus according to the present disclosure will be described with reference to FIGS. 1 to 4 and FIG. The processing device 11 of this embodiment differs from the processing device 11 of the above-described first embodiment in the function F22 for performing frequency analysis calculations. Other points of the processing apparatus 11 of the present embodiment are the same as those of the processing apparatus 11 of the first embodiment described above, so the same parts are denoted by the same reference numerals, and the description thereof is omitted.

FIG. 5 is a graph showing the relationship between the number of analysis peaks M of DFT in the second frequency analysis P6 by the function F22 of the processing device 11 performing frequency analysis calculations and the amount of calculation of the processing device 11 .
As shown in FIG. 5, when the number of power spectrum peaks extracted based on the result of the first frequency analysis P2, that is, the number of detected objects increases, the number of DFT analysis peaks in the second frequency analysis P6 increases.

Here, let M be the number of DFT analysis peaks in the second frequency analysis P6, let Nc be the number of the first continuous waves CW1 included in the first modulation period T1, which is the transmission period of the first continuous waves CW1, and let Nc be the number of the first continuous waves CW1. Let Ns be the number of samplings in one continuous wave CW1. In this case, when the DFT analysis peak number M exceeds the product of the number Nc of the first continuous waves CW1 and the sampling number Ns, the DFT calculation amount exceeds the FTT calculation amount for all peaks.

Therefore, the processing device 11 of the present embodiment performs the first frequency analysis P2 including the fast Fourier transform and extracts the number of peaks M, which is the number Nc of the first continuous waves CW1 included in the transmission period of the first continuous waves CW1. and the sampling number Ns in each first continuous wave CW1, that is, when M<Nc×Ns is satisfied, a second frequency analysis P6 including a discrete Fourier transform is performed. Further, when the number of peaks M is equal to or greater than the product, the processing device 11 of the present embodiment includes fast Fourier transform for the beat frequency of the second continuous wave CW2 instead of the second frequency analysis P6. A third frequency analysis is performed to calculate the distance, velocity and bearing of the object.

With such a configuration, the processing device 11 of this embodiment can prevent an increase in the amount of calculation compared to a conventional radar device.

Although the embodiment of the processing apparatus according to the present disclosure has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes, etc. within the scope of the present disclosure are possible. are intended to be included in this disclosure.

[Example] As an example of the processing device of the present disclosure, a radar device and a processing device having the same configuration as those of the above-described embodiments were prepared, and an object around the radar device was detected. In this example, the same FMCW was used as the first continuous wave and the second continuous wave. Tables 1 and 2 below show the amount of computation and the amount of memory used by the processing device of this embodiment. The number Nc of FMCWs included in the transmission periods of the first continuous wave and the second continuous wave is 128, and the number of samples Ns of each FMCW is 1024, which are extracted based on the result of the first frequency analysis. The peak number M of the obtained power spectrum was 15.

[Comparative Example] Next, FFT is performed twice on the beat frequency of the first continuous wave in the same manner as in the first frequency analysis, and FFT is performed on the beat frequency of the second continuous wave in the same manner as in the first frequency analysis. Objects around the radar apparatus were detected in the same manner as in the example, except that the detection was performed twice. Tables 3 and 4 below show the amount of computation and the amount of memory used in the processing device of this comparative example.

In the processing device of the example, the calculation amount and memory usage of the first frequency analysis are equivalent to those of the FFT for the beat frequency of the first continuous wave of the comparative example. However, the memory usage of the second frequency analysis by the processing apparatus of the example was reduced to about 50% of the memory usage of the FFT for the beat frequency of the second continuous wave of the comparative example. In addition, the processing apparatus of the present embodiment increases the number of types of FMCW from the two types of the first continuous wave and the second continuous wave to three or more types, thereby further increasing the effect of reducing the amount of calculation and the amount of memory used. be able to. It should be noted that the processing device of the present embodiment can reduce the amount of calculation compared to the processing device of the comparative example by changing the setting of the number of peaks M to be processed in the second frequency analysis P6.

10 radar device 11 processing device 12a1 first transmitting antenna 12a2 second transmitting antenna CW1 first continuous wave (frequency modulated continuous wave)
CW2 Second continuous wave (frequency modulated continuous wave)
M Number of peaks Nc Number of first continuous waves Ns Number of samples OA Analysis target P2 First frequency analysis P6 Second frequency analysis T1 First modulation period (transmission cycle of first continuous wave)
Δf1 Frequency deviation width of first continuous wave Δf2 Frequency deviation width of second continuous wave

Claims (5)

A processing device for performing signal processing for a radar device that transmits and receives a first continuous wave and a second continuous wave that are frequency-modulated continuous waves,
performing a first frequency analysis including a fast Fourier transform on the beat frequency of the first continuous wave to extract the peak of the power spectrum ;
The number of peaks extracted by performing the first frequency analysis is smaller than the product of the number of the first continuous waves included in the transmission period of the first continuous waves and the sampling number for each of the first continuous waves. , calculating the distance, velocity and bearing of the object by performing a second frequency analysis including a discrete Fourier transform on the beat frequency of the second continuous wave with the frequency corresponding to the peak as the analysis object ;
When the number of peaks is equal to or greater than the product, instead of performing the second frequency analysis, a third frequency analysis including a fast Fourier transform is performed on the beat frequency of the second continuous wave to determine the object distance. A processing device for calculating velocity and heading . 2. The processing apparatus according to claim 1, wherein said radar device is controlled to expand the frequency deviation width of said first continuous wave more than the frequency deviation width of said second continuous wave. 3. The processing apparatus according to claim 2, wherein said radar apparatus is controlled to alternately transmit and receive a plurality of said first continuous waves and a plurality of said second continuous waves. 3. The processing device according to claim 2, wherein the radar device is controlled to alternately transmit and receive one of the first continuous waves and one of the second continuous waves. 2. The processing device according to claim 1, wherein said radar device is controlled to switch between a first transmitting antenna and a second transmitting antenna arranged at different positions of said radar device.

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