JP2009008452A - Wide band radar device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent decline of target recognition accuracy caused by existence of an interference wave, concerning a wide band radar device. <P>SOLUTION: In this wide band radar device equipped with a transmitter for transmitting a wide band signal, and a receiver for receiving a reflected wave of the wide band signal transmitted from the transmitter, for recognizing the target based on a result of execution of band width synthesis of a plurality of sub-band signals having each mutually different frequency band in the reflected wave received by the receiver, an interference wave received by the receiver is detected, and when the interference wave is detected, a sub-band signal in a frequency band wherein the interference wave exists, is removed from sub-band signals in the frequency band to be subjected to the band width synthesis for recognizing the target. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a broadband radar apparatus, and in particular, a transmitter that transmits a plurality of subband signals in different frequency bands, and a receiver that receives a reflected wave of a subband signal transmitted from the transmitter. The present invention relates to a broadband radar device that recognizes a target based on a result of hand width synthesis of subband signals of each frequency band received as reflected waves by a receiver.

Conventionally, a radar apparatus that recognizes a target such as an object is known (see, for example, Patent Document 1). In this radar device, radio waves are transmitted and the reflected waves are received. Then, the target is recognized based on the relationship between the transmission signal and the reception signal. For example, the distance from the target and the speed of the target are detected based on the time from transmission of the transmission signal to reception of the reception signal. In this radar apparatus, transmission of radio waves from the transmitter is performed only for a time necessary for recognizing the target in order to prevent radar interference with radio waves used in other systems.
JP-A-6-138217

  However, in the above-described radar apparatus, when radar interference actually occurs, the relationship between the transmission signal and the reception signal deviates from that representing the regular target, and therefore the distance and speed with respect to the target are incorrect. May be detected.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a broadband radar apparatus capable of suppressing a reduction in recognition accuracy of a target due to the presence of an interference wave.

  The above object includes a transmitter that transmits a broadband signal and a receiver that receives a reflected wave of the broadband signal transmitted from the transmitter, and the frequency bands of the reflected waves received by the receiver are mutually different. A broadband radar device for recognizing a target based on a result of hand width synthesis of a plurality of different subband signals, an interference wave detection means for detecting an interference wave received by the receiver, and the interference wave detection When the interference wave is detected by the means, this is achieved by a broadband radar device comprising interference suppression means for suppressing the influence of the interference wave in recognizing the target.

  In the invention of this aspect, a broadband signal is transmitted from the transmitter, and a reflected wave of the broadband signal is received by the receiver. Then, the target is recognized by combining the bandwidths of subband signals of a plurality of frequency bands having different frequency bands in the received reflected wave. In the present invention, an interference wave received by the receiver is detected. And when an interference wave is detected, the influence by the interference wave in recognizing a target is suppressed. For this reason, it is possible to suppress a decrease in recognition accuracy of the target due to the presence of the interference wave.

  In the broadband radar apparatus described above, the interference suppression unit recognizes a target from a subband signal in a frequency band in which the interference wave exists when the interference wave is detected by the interference wave detection unit. If it is excluded from the subband signal of the frequency band that should be combined, the frequency band subband where the interference wave exists is not used when recognizing the target. It is possible to suppress a decrease in the recognition accuracy of the target.

  In the above-described wideband radar apparatus, the transmitter is a device that transmits a plurality of subband signals having different frequency bands as a wideband signal, and the interference suppression unit detects the interference wave by the interference wave detection unit. If the subband signal in the frequency band in which the interference wave exists from the transmitter is stopped when detected, the subband signal in the frequency band in which the interference wave exists is transmitted from the transmitter. Since it is not received and is not received by the receiver, it is possible to suppress a decrease in recognition accuracy of the target due to the presence of the interference wave.

  In the above-described broadband radar device, when the interference wave is detected by the interference wave detection unit, a plurality of divided band signals having different frequency bands obtained by dividing the subband signal of the frequency band in which the interference wave exists And a split interference band extracting unit that extracts a split band signal in a frequency band in which the interference wave exists, wherein the interference suppression unit detects the split when the interference wave is detected by the interference wave detecting unit. If the divided band signal in the frequency band in which the interference wave extracted by the interference band extracting means exists is excluded from the subband signals in the frequency band to be subjected to bandwidth synthesis in order to recognize the target, The subband signal of the small frequency band where the interference wave further divided among the subbands of the frequency band where the interference wave exists when recognizing Since not, it is possible to suppress the lowering of recognition accuracy of target object due to the presence of interference.

  Further, in the above-described broadband radar apparatus, if the center frequency of each subband signal is arranged according to the minimum redundant arrangement, the side lobe of the antenna can be suppressed low, so that even when interference waves exist It is possible to suppress a decrease in the recognition accuracy of the target.

  Further, in the above-described broadband radar apparatus, the interference suppression unit may detect a frequency corresponding to the interference wave so that the influence of the interference wave is suppressed when the interference wave is detected by the interference wave detection unit. If the template waveform is combined with the reflected wave received by the receiver, the interference wave is removed and the bandwidth synthesis of the subband signals in each frequency band is performed. It is possible to suppress a reduction in the recognition accuracy of the target that is caused.

  In the above-described broadband radar apparatus, the interference wave detecting means detects the interference wave based on the correlation of subband signals in each frequency band in the reflected wave received by the receiver. Good.

  According to the present invention, it is possible to suppress a decrease in recognition accuracy of a target due to the presence of an interference wave.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a configuration diagram of a broadband radar apparatus 10 according to a first embodiment of the present invention. FIG. 2A shows a wideband signal used in this embodiment, and FIG. 2B shows a subband signal obtained by dividing the wideband signal used in this embodiment. The broadband radar apparatus 10 according to the present embodiment is mounted on a moving object such as a vehicle or a fixed object around which the moving object moves, and recognizes an object (target) existing around the moving object or the fixed object. Radar device.

  As shown in FIG. 1, the broadband radar apparatus 10 includes a signal generator 12. The signal generator 12 generates a broadband signal as shown in FIG. 2A having a bandwidth of 0 to 2 GHz, for example. The broadband signal generated by the signal generator 12 is a chirp signal in which the frequency of the output signal sequentially changes in the time axis, or an impulse pulse signal whose pulse width on the time axis is sufficiently narrower than that of the broadband signal. This pulse signal is a wideband signal with an occupied bandwidth of 0 to 2 GHz and a bandwidth of 2 GHz on the frequency axis.

  A radar pulse generation circuit 14 is connected to the signal generator 12. The broadband signal generated by the signal generator 12 is supplied to the radar pulse generation circuit 14. The radar pulse generation circuit 14 is a circuit that divides the wideband signal supplied from the signal generator 12 into a plurality of narrowband subband signals having different frequencies (shown by a solid line in FIG. 2B). The radar pulse generation circuit 14 includes a power distributor 16 and a plurality of (for example, eight) band-pass filters 18. The power distributor 16 distributes the wideband signal supplied from the signal generator 12 to a predetermined number (a predetermined number of subband signals to be obtained by dividing the wideband signal), and a plurality of bandpass filters. 18 is a device to be supplied.

Each bandpass filter 18 is a filter that passes a subband signal with a bandwidth fb of several tens to several hundreds of MHz, and the center frequency f _k (k) of the subband signal that each bandpass filter 18 passes. = 1 to 8) are arranged so as not to overlap with each other in the 0 to 2 GHz band. For example, the bandwidth fb of each subband signal is set to 85 MHz, and the center frequencies _fk of the subband signals are set to 42 MHz, 125 MHz, 375 MHz, 875 MHz, 1375 MHz, 1542 MHz, 1792 MHz, and 1959 MHz, respectively. Each of the bandpass filters 18 divides the wideband signal and allows the narrowband subband signal to pass through without gaps or with a gap therebetween.

  A transmission circuit 20 is connected to the radar pulse generation circuit 14. The subband signal generated by the radar pulse generation circuit 14 is supplied to the transmission circuit 20. The transmission circuit 20 is a circuit that mixes a carrier wave with the subband signal supplied from the radar pulse generation circuit 14 and up-converts it to a high-frequency signal. Each transmission circuit 20 includes a plurality of mixers 22, a local oscillator 24, a power amplifier 26, and a band pass filter 28. Each of the elements 22 to 28 of the transmission circuit 20 is provided in the same number as the band-pass filter 18 (that is, the number of subband signals to be obtained by dividing a wideband signal).

  The subband signals generated by each bandpass filter 18 of the radar pulse generation circuit 14 are input to the corresponding mixers 22 respectively. Each mixer 22 is supplied with a carrier signal (frequency fc; for example, 24 GHz) from a corresponding local oscillator 24. Each mixer 22 frequency-converts (up-converts) the subband signal supplied from the corresponding bandpass filter 18 into an RF band signal (fc to fc + 2 GHz band).

  The output of each mixer 22 is supplied to the corresponding power amplifier 26. Each power amplifier 26 amplifies the subband signal supplied from the corresponding mixer 22 to an amplitude suitable as a transmission signal. The output of each power amplifier 26 is supplied to the corresponding band pass filter 28. Each band-pass filter 28 passes a signal of a necessary band including the up-converted sub-band signal supplied from the corresponding power amplifier 26.

  A transmission antenna 30 is connected to the transmission circuit 20. As many transmission antennas 30 as the number of subband signals to be divided are provided. The output of each band pass filter 28 of the transmission circuit 20 is supplied to the corresponding transmission antenna 30. In this case, a plurality of subband signals in the RF band are radiated from the transmitting antenna 30 toward the periphery where the target is to be recognized. For example, in the case of an in-vehicle radar, the light is emitted toward the front of the vehicle or the rear of the vehicle.

  Since the transmission circuit 20 has an independent configuration for each subband signal, the carrier waves supplied to the mixer 22 by each local oscillator 24 do not have to be the same frequency, and may be different from each other. In this case, each subband signal can be transmitted using an arbitrary band.

  The broadband radar apparatus 10 includes a receiving antenna 32. The reception antennas 32 are provided in the same number as the subband signals to be divided. The reception antenna 32 receives a plurality of transmission side subband signals transmitted from the transmission side as reflected waves after being reflected by an object. A reception circuit 34 is connected to the reception antenna 32. The reception signal received by the reception antenna 32 is supplied to the reception circuit 34. The reception circuit 34 is provided corresponding to the transmission circuit 20 described above, and is a circuit that removes a carrier wave from the reception signal supplied from the reception antenna 32 and down-converts it to a low-frequency signal.

  The receiving circuit 34 includes a plurality of bandpass filters 36, a low noise amplifier 38, a mixer 40, a local oscillator 42, and a bandpass filter 44. The elements 36 to 44 of the receiving circuit 34 are provided in the same number as the subband signals to be divided. The reception signal received by the reception antenna 32 is input to the band pass filter 36. Each band-pass filter 36 is a filter that passes a signal in a frequency band corresponding to each band-pass filter 36, and extracts a reception signal in a band of a reflected wave reflected by the target.

  The reception signal generated by each band pass filter 36 is amplified by the corresponding low noise amplifier 38 and input to the mixer 40. Each mixer 40 is supplied with a carrier wave signal from a corresponding local oscillator 42. The oscillation frequency of this carrier wave signal is set corresponding to the frequency fc of the carrier wave signal of the local oscillator 24 on the transmission side. Each mixer 40 mixes the received signal supplied from the corresponding bandpass filter 36 with a carrier wave and performs frequency conversion (down-conversion) to a reception-side subband signal in the 0 to 2 GHz band. The output of each mixer 40 is supplied to the corresponding band pass filter 44. Each band-pass filter 44 passes a signal of a necessary band including a down-converted reception-side subband signal supplied from the corresponding mixer 40.

  A radar pulse synthesis circuit 46 is connected to the reception circuit 34. The output of each band pass filter 44 of the receiving circuit 34 is supplied to a radar pulse synthesis circuit 46. The radar pulse synthesis circuit 46 includes a plurality of AD conversion circuits 48, correlators 50, interference determination circuits 52, and a single bandwidth synthesis circuit 54. Each of the elements 48 to 52 of the radar pulse synthesizing circuit 46 is provided in the same number as the band-pass filter 44 (that is, the number of subband signals to be obtained by dividing a wideband signal).

  The AD conversion circuit 48 receives the output of the bandpass filter 44 (reception-side subband signal) and further receives the output of the bandpass filter 18 of the radar pulse generation circuit 14 (transmission-side subband signal). The Each AD conversion circuit 48 converts the reception side subband signal supplied from the corresponding bandpass filter 44 into digital data, and converts the transmission side subband signal supplied from the corresponding bandpass filter 18 into digital data. Convert to

  The reception-side subband signal and the transmission-side subband signal converted into digital data by each AD conversion circuit 48 are supplied to corresponding correlators 50, respectively. Each correlator 50 performs a correlation operation between the reception-side subband signal supplied from the corresponding AD conversion circuit 48 and the transmission-side subband signal supplied from the corresponding bandpass filter 18. The correlation calculation by the correlator 50 is performed in two types, a coarse search and a fine search, as will be described in detail later.

  The result of the correlation calculation by the correlator 50 is supplied to the bandwidth synthesis circuit 54 via the interference determination circuit 52 described in detail later. The bandwidth synthesis circuit 54 performs bandwidth synthesis on the plurality of subband signals from the correlator 50. Specifically, the delay time of the received signal relative to the transmission signal is corrected based on the difference in spectrum phase for each different frequency in one subband signal, and the entire subband signal is integrated (all Channel) and a corrected delay time Δτ ′. The result of the delay time Δτ ′ obtained by the bandwidth synthesis circuit 54 is supplied to a target measurement unit (not shown). The target measurement unit calculates a relative distance R (= c · Δτ ′ / 2; where c is the speed of light) from the target based on the delay time Δτ ′ supplied from the bandwidth synthesis circuit 54. To do. The target measuring unit may calculate a relative speed or a relative acceleration with the target together with or in place of the relative distance R with the target.

Each output (transmission-side subband signal) supplied from the transmission-side bandpass filter 18 to the reception-side AD conversion circuit 48 may be frequency-converted into a baseband band. Specifically, the transmission side subband signals from each bandpass filter 18 are respectively supplied to the corresponding mixers, and the oscillation frequency is set to the center frequency f _k (K = 1 to 8) of the subband signals. Mixed with the signal from the local oscillator. Therefore, the output of each of these mixers (that is, the transmission side subband signal input to the AD conversion circuit 48) is all frequency-converted into a baseband signal whose center frequency is fb (subband signal bandwidth) / 2. Is done.

Here, if the transmission side subband signal is x _k (t) and the reception side subband signal is y _k (t), the baseband band subband signals x _k ^v (t) and y _k ^v (t) The following equations (1) and (2) are satisfied. Note that f _k is the center frequency of the k-th subband signal.

x _k (t) = x _k ^v (t) · e ^{i2π (fk−0.5fb) t} (1)
y _k (t) = y _k ^v (t) · e ^{i2π (fk−0.5fb) t} (2)
Each AD conversion circuit 48 converts the baseband subband signals x _k ^v (t) and y _k ^v (t) supplied from the corresponding band pass filter 18 side into digital data. Since the AD conversion circuit 48 digitally converts the subband signal in the baseband, the sampling frequency necessary for the AD conversion circuit 48 is 2 · fb (Hz) or more, for example, 170 MHz. In this way, if the baseband subband signal is digitally converted, the sampling frequency of the AD conversion circuit 48 can be reduced.

By the way, in the present embodiment, the radar pulse synthesizing circuit 46 performs a rough search for obtaining the correlation of the transmission signal corresponding to each subband signal, and a plurality of subbands as the correlation calculation for obtaining the delay time of the reception signal with respect to the transmission signal. Perform both fine search to obtain the overall correlation by integrating signals. Hereinafter, these contents will be described. In the following description, subband signals x _k ^v (t) and y _k ^v (t) in the baseband band are used.

<Coarse search>
First, the rough search will be described. In the radar pulse synthesis circuit 46, each correlator 50 performs a correlation operation between the reception side subband signal supplied from the corresponding AD conversion circuit 48 and the transmission side subband signal supplied from the corresponding bandpass filter 18. Thus, the delay time of the reception signal with respect to the transmission signal is obtained. Here, the reception side subband signal is y _k (t _j ), the transmission side subband signal corresponding to the reception side subband signal is x _k (t _j ), and these baseband signals are x _k. ^{Assuming v} (t _j ) and y _k ^v (t _j ), each correlator 50 obtains a correlation between x _k (t _j ) and y _k (t _j ). Specifically, x _k ^v _{(t j)} is a spectrum obtained by Fourier transform of _X ^k v a ^{_{(f j), y k v}} (t j) is a spectrum obtained by Fourier transform of _Y ^k v _{(f j)} cross the spectrum _S ^k v ( f _j ) is obtained. Note that * represents a complex conjugate.

S _k ^v (f _j ) = X _k ^v (f _j ) · Y _k ^{v *} (f _j ) (3)
Information of the mutual spectrum S _k ^v (f _j ) corresponding to the channel of each subband signal is supplied to the bandwidth synthesis circuit 54 except in the case described below. First, the bandwidth combining circuit 54 obtains a correlation function F _k (Δτ) for each channel's mutual spectrum S _k ^v (f _j ) by the following equation (4). Note that j = 1 to J. J is the number of subband signals, and fjv is the frequency for the baseband band index j.

F _k (Δτ) = (1 / (J−1)) Σ {S _k ^v (f _j ) · e ^{−i 2πfjvΔτ} } (4)
Then, the bandwidth synthesis circuit 54 obtains a rough determination search function F (Δτ) obtained by summing up the correlation functions of the respective channels by the following equation (5), and then obtains Δτ that maximizes the F (Δτ). Note that the value of Δτ obtained is Δτ _s .

F (Δτ) = Σ {F _k (Δτ)} (k = 1 to n) (5)
Here, since the received signal is reflected and returned to the target such as the object or oncoming vehicle, if the transmission signal is delayed by the delay time, the correlation between the transmission signal and the received signal is the largest. Become. Hereinafter, a case where the mutual spectrum X (f) · Y ^* (f) between the transmission signal and the reception signal is obtained while giving a predetermined delay time τ to the transmission signal will be considered. If τ is changed, the delay time τ that maximizes the overall correlation between the transmission signal and the reception signal can be obtained.

When the Fourier transform of the transmission signal x (t) is X (f), the Fourier transform of x (t + Δτ) shifted by Δτ with respect to x (t) is X ′ (f) = X (f) · e ^−iφ . However, φ = 2πfΔτ, and f is a frequency.

The delay of Δτ on the time axis appears as a phase shift proportional to the frequency after Fourier transform. That is, if the transmission signal is delayed by Δτ on the time axis, the phase of the component is rotated more greatly as the frequency is higher on the frequency axis after Fourier transform. Accordingly, X (f) · Y ^* (f) · e ⁻ is obtained by correcting the phase by Δτ with respect to the mutual spectrum X (f) · Y ^* (f) of x (t) and y (t). It can be expressed as ^i2πfΔτ .

In this regard, changing Δτ corresponds to rotating the phase of Y ^* (f), and it is possible to obtain a plausible delay time Δτ by searching for a delay time that maximizes the correlation. The delay time Δτ can be obtained by performing an independent correlation operation for each subband signal. Then, by obtaining Δτ that maximizes the sum of correlations F (Δτ) for all subband signals, it is possible to obtain the search result Δτ _s of the coarse search.

<Fine search>
Next, the bandwidth synthesis circuit 54 obtains a fine search function D (Δτ ′) that is a correlation function obtained by synthesizing all channels by the following equation (6), and the correlation is maximized using the function D (Δτ ′). A delay time Δτ ′ is obtained. Note that k = 1 to N. F0k is the center frequency of the RF frequency band of the kth subband channel, Δφk is the value of the phase shift in the transmission / reception circuit of the kth subband signal, and N is the number of subband signals. It is.

D (Δτ ′) = (1 / N) Σ {F _k (Δτ _s ) · e− ^{i (2πf0kΔτ ′ + Δφk} } (6)
Then, Δτ ′ that maximizes D (Δτ ′) is obtained. The obtained Δτ ′ becomes the delay time of the radar pulse, and based on this, the relative distance R to the target is obtained.

  Here, the coarse search is a correlation operation for obtaining a delay time by compensating the phase of each subband signal. For this reason, if the entire band of the wideband signal is viewed, there is a possibility that the phase is rotated for the mutual spectrum of the other subband signal even when the phase is not rotated for the mutual spectrum of one subband signal. . Therefore, if the delay time is changed slightly and the maximum value is obtained for the correlation obtained by integrating the subband signals of all channels, the phase based on the difference in frequency for each subband signal can be compensated. This is to obtain Δτ ′ that maximizes the aforementioned D (Δτ ′).

  In the present embodiment, each subband signal is a signal having a center frequency separated from each other. For this reason, a phase shift exceeding 360 ° cannot be determined. That is, a phase shift of 0.1 rotation cannot be distinguished from a phase shift of 1.1 rotation or 2.1 rotation. On the other hand, in the present embodiment, the coarse search is performed before the fine search is performed. Since Δτ obtained by the coarse search does not cause an error phase shift exceeding 360 °, therefore, according to the fine search, Δτ ′ having high accuracy can be selected by Δτ obtained by the coarse search.

Instead of inputting the transmission side subband signal x _k (t) or x _k ^v (t) from the transmission side bandpass filter 18 to the radar pulse synthesis circuit 46 as in this embodiment, A memory for storing information on the transmitting side subband signal used for the correlation calculation may be provided.

In this memory, the frequency spectrum X _k ^v (f _j ) _obtained by frequency-converting the transmission-side subband signal x _k (t _j ) to baseband and further Fourier-transforming is calculated and stored in advance. Thereby, the radar pulse synthesizing circuit 46 obtains the subband signal x _k (t _j ) from the broadband signal that is the radar pulse, converts it to the baseband subband signal x _k ^v (t _j ), and It is not necessary to perform processing for obtaining Fourier-transformed X _k ^v (f _j ).

  In this configuration, in order to detect the arrival delay time, it is necessary for the radar pulse synthesizing circuit 46 to grasp the timing (transmission timing) at which the broadband signal is generated from the signal generator 12. The delay of the transmission side subband signal can be realized by shifting the timing of reading from the memory from the generation timing of the wideband signal.

  As described above, according to the wideband radar apparatus 10 of the present embodiment, the delay time of the reception signal with respect to the transmission signal is obtained by performing the bandwidth synthesis for the plurality of subband signals, and based on the delay time, The relative distance R can be calculated, and thereby, a target existing in the vicinity can be recognized.

  By the way, although the broadband radar apparatus 10 of this embodiment uses a broadband signal for recognizing a target, it may cause interference with radio waves of an existing wireless system (for example, a wireless communication system used for a mobile phone). is there. When such radar interference occurs, a band with an increased power level appears in a part of the entire band of the wideband signal. The subband signal in that band calculates the delay time of the received signal with respect to the transmission signal as usual. As a result, the delay time of the reception signal with respect to the transmission signal deviates from that representing the regular target, and as a result, the relative distance R to the target may be erroneously detected.

  Therefore, the broadband radar apparatus 10 according to the present embodiment is characterized in that even when an interference wave is present in a part of the broadband signal, a reduction in recognition accuracy of the target due to the presence of the interference wave is prevented. ing. Hereafter, the characteristic part of a present Example is demonstrated with reference to FIG. 3 thru | or FIG.

  FIG. 3 is a diagram illustrating a state in which an interference wave exists in a part of the entire band of the wideband signal. 3A shows a case where the subband signals constituting the wideband signal are arranged without a gap on the frequency, and FIG. 3B shows a case where the subband signals constituting the wideband signal are on the frequency. Each case is shown with a gap. FIG. 4 shows a flowchart of an example of a control routine executed in the broadband radar apparatus 10 of the present embodiment. FIG. 5 is a diagram for explaining a method of determining the presence / absence of interference (presence / absence of interference wave) in the band of each subband signal in the broadband radar apparatus 10 of the present embodiment.

In the wideband radar apparatus 10 of the present embodiment, each correlator 50 of the radar pulse synthesizing circuit 46 performs a rough search on each subband signal to thereby correlate the transmission side subband signal and the reception side subband signal (for example, The spectra X _k ^v (f _j ), Y _k ^v (f _j ) and the mutual spectrum S _k ^v (f _j )) are obtained (step 100). Before the spectrum information corresponding to the subband signal of each channel is supplied to the bandwidth synthesis circuit 54, it is first supplied to the corresponding interference determination circuit 52.

Each interference determination circuit 52 performs a rough determination search (correlation calculation) for the subband signal of its own band based on the spectrum information supplied from the corresponding correlator 50, and the presence of an interference wave based on the search result. The presence or absence is determined (step 102). For example, the SN ratio is obtained using the transmission side spectrum X _k ^v (f _j ) and the reception side spectrum Y _k ^v (f _j ) for the corresponding subband signal, the side lobe level is measured, and the SN ratio is calculated. The presence / absence of an interference wave in that band may be determined based on this. In this configuration, when the SN ratio is equal to or greater than a predetermined threshold, it is determined that there is no interference wave. On the other hand, when the SN ratio is less than the predetermined threshold, it is determined that there is an interference wave.

Further, an average value of power levels in the band is obtained using the mutual spectrum S _k ^v (f _j ) of the transmission side spectrum X _k ^v (f _j ) and the reception side spectrum Y _k ^v (f _j ), and the average The presence / absence of an interference wave in the band may be determined based on the value. In this configuration, when the average value is equal to or less than a predetermined threshold value, it is determined that no interference wave exists. On the other hand, when the average value exceeds a predetermined threshold value, it is determined that an interference wave exists.

Further, using the cross spectrum S _k ^v (f _j ), a shape (correlation shape; for example, a periodic peak) in the band is recognized, and whether or not the correlation shape is a desired shape. The presence / absence of an interference wave in the band may be determined. In such a configuration, when the correlation shape is a desired shape, it is determined that there is no interference wave. On the other hand, when the correlation shape is not a desired shape, it is determined that an interference wave exists.

A single bandwidth combining circuit 54 is connected to the interference determination circuit 52. The output of each interference determination circuit 52 is supplied to the bandwidth synthesis circuit 54. Specifically, when each interference determination circuit 52 determines that there is no interference wave for the subband signal in its own band, the information of the mutual spectrum S _k ^v (f _j ) supplied from the correlator 50 is obtained. The data is supplied to the bandwidth synthesis circuit 54 as usual (step 104). On the other hand, when it is determined that the interference wave exists, the information of the cross spectrum S _k ^v (f _j ) supplied from the correlator 50 is not supplied to the bandwidth synthesis circuit 54 or the information is bandwidth synthesized. Even if it is supplied to the circuit 54, information indicating that the interference wave is superimposed on the subband signal is added (step 106).

When the bandwidth combining circuit 54 receives the information on the cross spectrum S _k ^v (f _j ) from the correlator 50 as usual from all the interference determination circuits 52 (negative determination in step 108), the bandwidth combining circuit 54 A coarse-decision search function F (Δτ) obtained by summing all is obtained, Δτ that maximizes the F (Δτ) is obtained, and a fine-decision search function D (Δτ ′) that is a correlation function obtained by synthesizing all channels is obtained. Using the function D (Δτ ′), a delay time Δτ ′ that maximizes the correlation is obtained (step 110). In this case, the correlation of the subband signals of all channels over the entire band of the wideband signal is obtained, and the relative distance R to the target is calculated.

On the other hand, the bandwidth combining circuit 54 receives the information of the mutual spectrum S _k ^v (f _j ) from the correlator 50 from the plurality of interference determination circuits 52 as usual, but the interference determination circuit 52 covers a certain band. If the information on the mutual spectrum S _k ^v (f _j ) by the correlator 50 is not received from the receiver, or if the information is received but the information indicating that the interference wave is superimposed (positive determination in step 108). Then, after grasping the band (interference band) on which the interference wave is superimposed, the channel of the interference band is excluded and the bandwidth synthesis is performed. When subband signals obtained by dividing a wideband signal are arranged with no gaps in frequency, the entire band excluding the interference band in which the interference wave exists (the area surrounded by the slanted line in FIG. 3A) is subjected to bandwidth synthesis. In addition, when the subband signals are arranged with a gap in frequency, a part of the band excluding the interference band in which the interference wave exists (the area surrounded by the diagonal line in FIG. 3B) is excluded. Bandwidth synthesis is performed (step 112).

  Specifically, a coarse-decision search function F (Δτ) obtained by summing the correlation functions of the subband signals of each channel for the band excluding the interference band is obtained, and Δτ that maximizes the F (Δτ) is obtained. Then, a fine-decision search function D (Δτ ′), which is a correlation function obtained by synthesizing subband signals of channels excluding the channels in the interference band, is obtained, and the delay time at which the correlation is maximized using the function D (Δτ ′) Δτ ′ is obtained. In this case, the correlation of the subband signal is obtained for the channel excluding the interference band among all the channels over the entire band of the wideband signal, and the relative distance R to the target is calculated.

  In this embodiment, there are a plurality (for example, eight) of narrowband subband signals obtained by dividing a wideband signal. For this reason, even if an interference wave is superimposed on a subband signal in a certain band, bandwidth synthesis is performed on subband signals in at least two bands other than the interference band (preferably, bands at both ends of the entire band). If it can be performed, the relative distance R to the target can be calculated with a certain degree of accuracy compared to the configuration in which the bandwidth synthesis is performed including the subband signal of the interference band on which the interference wave is superimposed. .

  Therefore, according to the wideband radar apparatus 10 of the present embodiment, even when an interference band in which the interference wave is superimposed exists and the interference wave is detected, a plurality of subband signals are bandwidth-combined to obtain the target. When calculating the relative distance R, the subband signal in the interference band can be excluded, and the influence of the interference wave in recognizing the target can be suppressed. For this reason, in the broadband radar apparatus 10 of the present embodiment, it is possible to calculate the relative distance R with respect to the target while maintaining high accuracy, and the recognition accuracy of the target due to the presence of the interference wave is reduced. It becomes possible to deter, and as a result, the maximum distance at which the target can be recognized can be extended.

In the present embodiment, the center frequencies f _k (k = 1 to n) of the subband signals that are passed through by each band-pass filter 18 on the transmitter side are separated from each other in the band of 0 to 2 GHz. For example, as described above, when the number of subband signals to be obtained by dividing a wideband signal is 8 (n = 8), 42 MHz, 125 MHz, 375 MHz, 875 MHz, It is set to 1375 MHz, 1542 MHz, 1792 MHz, and 1959 MHz. At this time, the interval between the center frequencies _fk of the adjacent subband signals has a ratio of 1: 3: 6: 6: 2: 3: 2 in order, and the center frequency _fk of each subband signal is the minimum. Arranged according to the redundant arrangement.

In general, the minimum redundant array is an array in which each element is arranged so that the redundancy between them is minimized, and is defined by the relationship between the number of elements as shown in FIG. 6 and the interval between adjacent elements. Can be obtained based on a rule of thumb. For example, when the number of subband signals to be obtained by dividing a wideband signal is four (n = 4), the center frequencies f _k of the four subband signals are adjacent to each other as shown in FIG. If it is arranged so that the interval between the subband signals becomes a ratio of 1: 3: 2, the redundancy between subband signals can be minimized.

Therefore, if the center frequency _fk of each subband signal is arranged according to the minimum redundant arrangement as in this embodiment, when an interference wave is superimposed on a subband signal in any band, the subband signal in that interference band Can be excluded in calculating the relative distance R to the target, the side lobes can be kept low compared to a configuration in which the center frequencies _fk of the subband signals are arranged at equal intervals with the adjacent ones. be able to. For this reason, in the broadband radar apparatus 10 of the present embodiment, even when interference occurs, it is possible to suppress a decrease in the recognition accuracy of the target and maintain the distance measurement accuracy.

In the first embodiment, the signal generator 12, the radar pulse generation circuit 14, the transmission circuit 20, and the transmission antenna 30 are included in the "transmitter" described in the claims, the reception antenna 32, the reception circuit. 34, the radar pulse synthesizing circuit 46 corresponds to the “receiver” recited in the claims, and each interference determination circuit 52 corresponds to the “interference wave detecting means” recited in the claims. Further, the bandwidth synthesis circuit 54 does not receive the information of the cross spectrum S _k ^v (f _j ) from the correlator 50 from the interference determination circuit 52 covering a certain band, or receives the information but does not interfere. When the information indicating that the wave is superimposed is received, the “interference suppression unit” described in the claims is realized by performing bandwidth synthesis by excluding the interference band where the interference wave is superimposed ing.

  By the way, in the first embodiment described above, when it is detected that an interference wave exists for a subband signal in its own band based on the spectrum information supplied from the correlator 50, the subband signal in that interference band is detected. Is excluded from the subband signal of the band to be combined in calculating the relative distance to the target in the bandwidth combining circuit 54 on the receiver side, but the present invention is not limited to this. Instead, the transmission of the subband signal in the interference band from the transmitter side may be stopped. In the configuration of such a modified example, since the subband signal itself on which the interference wave is superimposed is not received on the receiver side, the influence of the interference wave can be suppressed in calculating the relative distance to the target, It is possible to obtain the same effect as the configuration of the first embodiment described above.

  In the configuration of the modified example, as a technique for stopping transmission of the subband signal in the interference band, for example, transmission from the interference determination circuit 52 corresponding to the subband signal to the corresponding power amplifier 26 or local oscillator 24 is stopped. By supplying a command, power supply to the power amplifier 26 corresponding to the subband signal may be stopped, or driving of the local oscillator 24 corresponding to the subband signal may be stopped. In this case, the power amplifier 26 and the local oscillator 24 are not supplied with power or stopped in accordance with a transmission stop command from the interference determination circuit 52, whereby the “interference suppression unit” described in the claims is realized. It will be.

  In the first embodiment described above, when the interference wave is superimposed on the subband signal, all the bands covered by the subband signal are excluded from the bands to be combined in the bandwidth when calculating the relative distance R to the target. I am going to do that. On the other hand, in the second embodiment of the present invention, a subband signal in an interference band on which interference waves are superimposed is further divided into a plurality of narrowband subband signals having different frequencies (this signal is referred to as a divided subband signal). ), And only the band of the divided subband signal on which the interference wave is superimposed is excluded from the band to be subjected to the bandwidth synthesis in calculating the relative distance R with the target.

  FIG. 8 shows a configuration diagram of the broadband radar apparatus 100 of the present embodiment. In FIG. 8, parts that are the same as the parts shown in FIG. 1 are given the same reference numerals, and descriptions thereof will be omitted or simplified. FIG. 9 shows a specific configuration diagram of a main part of the broadband radar apparatus 100 of the present embodiment. FIG. 10 is a diagram for explaining a method of excluding only the band of the divided subband signal on which the interference wave is superimposed in the wideband radar apparatus 100 of the present embodiment from the band to be subjected to the bandwidth synthesis. FIG. 11 shows a flowchart of an example of a control routine executed in the broadband radar apparatus 100 of the present embodiment. In FIG. 11, the same steps as those in the routine shown in FIG. 4 are denoted by the same reference numerals, and the description thereof is omitted or simplified.

  That is, in the broadband radar apparatus 100 of the present embodiment, a radar pulse synthesizing circuit 102 is connected to the receiving circuit 34 as shown in FIG. The radar pulse synthesis circuit 102 includes a plurality of AD conversion circuits 48, correlators 50, interference determination circuits 52, division removal circuits 104, and a single bandwidth synthesis circuit 54. The respective elements 48 to 52 and 104 of the radar pulse synthesizing circuit 102 are provided in the same number as the band-pass filter 44 (that is, the number of subband signals to be obtained by dividing a wideband signal).

A single bandwidth synthesis circuit 54 is connected to the interference determination circuit 52, and a corresponding division removal circuit 104 is connected to each of them. When each interference determination circuit 52 determines that there is no interference wave for a subband signal in its own band, the interference determination circuit 52 normally _obtains information on the mutual spectrum S _k ^v (f _j ) of the subband signal supplied from the correlator 50. Then, the data is supplied to the bandwidth synthesis circuit 54 (step 104). On the other hand, when it is determined that the interference wave exists, the information on the mutual spectrum S _k ^v (f _j ) of the subband signal supplied from the correlator 50 is supplied to the division removal circuit 104.

  As shown in FIG. 9, each division removal circuit 104 includes a plurality of bandpass filters 106, mixers 108, a local oscillator 110, a bandpass filter 112, and a single bandwidth synthesis circuit 114. Each element 106 to 112 of the division removal circuit 104 is provided by the number of divided subband signals to be obtained by dividing one subband signal.

Information on the cross spectrum S _k ^v (f _j ) of the subband signal supplied from the correlator 50 to the division removal circuit 104 is input to each band pass filter 106. Each bandpass filter 106 has a bandwidth smaller than the bandwidth fb of the subband signal (more specifically, a bandwidth equal to or smaller than the bandwidth fb of the subband signal divided by the number of divided subband signals). This is a filter that passes the divided sub-band signals, and the center frequency of the divided sub-band signals that each band-pass filter 106 passes is arranged so that the bands do not overlap with each other in the band of the corresponding sub-band signal. Has been. Each of the bandpass filters 106 divides the corresponding subband signals and allows the narrowband divided subband signals to pass through without gaps or with a gap therebetween (step 200).

  The divided subband signals generated by each bandpass filter 106 are input to the corresponding mixers 108 respectively. Each mixer 108 is supplied with a high frequency signal from a corresponding local oscillator 110. Each mixer 108 mixes a high frequency with the divided subband signal supplied from the corresponding bandpass filter 106 and performs frequency conversion (up-conversion) to a high frequency divided subband signal. The output of each mixer 108 is supplied to a corresponding bandpass filter 112. Each band pass filter 112 band-passes a signal of a necessary band including an up-converted divided sub-band signal of its own band supplied from the corresponding mixer 108.

  The output of each band pass filter 112 is supplied to the bandwidth synthesis circuit 114. The bandwidth synthesis circuit 114 performs bandwidth synthesis on the plurality of divided subband signals from the bandpass filter 112. Specifically, after extracting the divided subband signals in the interference band where the interference wave is superimposed from all the divided subband signals, the subband signals corresponding to the self are excluded from the divided subband signals in the interference band. (Step 200). The result of the bandwidth synthesis obtained by the bandwidth synthesis circuit 114 is supplied to the bandwidth synthesis circuit 54 (step 202).

When the bandwidth combining circuit 54 receives the information of the cross spectrum S _k ^v (f _j ) of the subband signal by the correlator 50 from all the interference determination circuits 52 as usual, it sums all the correlation functions of the respective channels. The coarse-decision search function F (Δτ) is obtained, Δτ that maximizes the F (Δτ) is obtained, and a fine-decision search function D (Δτ ′) that is a correlation function obtained by synthesizing all the channels is obtained. Using (Δτ ′), a delay time Δτ ′ that maximizes the correlation is obtained (step 204). In this case, the correlation of the subband signals of all the channels over the entire band of the wideband signal is obtained, and the relative distance R to the target is calculated.

On the other hand, the bandwidth synthesizing circuit 54 does not receive the information of the mutual spectrum S _k ^v (f _j ) of the subband signal by the correlator 50 directly from the interference determination circuit 52 covering a certain band, and When the characteristic information of the subband signal in the interference band is received from the division removal circuit 104 connected to the interference determination circuit 52, the correlation functions of the subband signals of all channels including the subband signal in the interference band are summed. The coarse-decision search function F (Δτ) is obtained, Δτ that maximizes the F (Δτ) is obtained, and a sub-band signal of all channels including the sub-band signal of the interference band is synthesized. The decision search function D (Δτ ′) is obtained, and the delay time Δτ ′ that maximizes the correlation is obtained using the function D (Δτ ′) (step 204). In this case, the correlation of the subband signals is obtained for all channels over the entire band of the wideband signal, including the channels of the subband signals of the interference band from which the divided subband signals of the interference band are removed. Relative distance R is calculated.

  In this embodiment, there are a plurality of narrow-band divided subband signals obtained by dividing the subband signals. For this reason, when an interference wave is superimposed on a subband signal, all the interference bands of the subband signal should be combined in calculating the relative distance R to the target as in the first embodiment. Unlike the configuration excluding the subband signal band (hereinafter referred to as the contrast configuration), only the subband signal band of the interference band in which the interference wave is superimposed among the subband signals of the interference band is relative to the target. In calculating the distance R, if it is excluded from the band of the subband signal to be synthesized, the interference wave is detected in calculating the relative distance R with respect to the target as compared with the comparison configuration. In this case, the band to be excluded can be reduced, and the relative distance R to the target can be calculated with a certain degree of accuracy.

  Therefore, according to the wideband radar apparatus 100 of the present embodiment, even when an interference band where the interference wave is superimposed exists and the interference wave is detected, a plurality of subband signals are synthesized with the bandwidth to obtain the target. In calculating the relative distance R of the subband signal, the band of the other divided subband signal is used while excluding only the interference band of the divided subband signal in which interference actually occurs among the subband signals of the interference band. And the influence of the interference wave in recognizing the target can be removed. For this reason, in the broadband radar apparatus 100 of the present embodiment, it is possible to calculate the relative distance R with respect to the target while maintaining high accuracy, compared to the broadband radar apparatus 10 of the first embodiment. It is possible to suppress a decrease in the recognition accuracy of the target due to the presence of the interference wave, and thus it is possible to extend the maximum distance at which the target can be recognized.

  The configuration of the wideband radar device 100 is such that the smaller the number of subband signals that should divide the wideband signal, the less the influence of interference waves and the lower the recognition accuracy of the target. It is effective in doing.

  In the second embodiment, the receiving antenna 32, the receiving circuit 34, and the radar pulse synthesizing circuit 102 correspond to the “receiver” recited in the claims. In addition, the bandwidth synthesis circuit 114 of each division removal circuit 104 extracts the divided subband signals in the interference band on which the interference wave is superimposed from all the divided subband signals from the bandpass filter 112. The described “divided interference band extracting means” is configured such that, when the bandwidth combining circuit 54 receives the characteristic information of the subband signal in the interference band from the division removal circuit 104, the interference wave is included in the interference band of the subband signal. The "interference suppression means" described in the claims can be realized by performing the bandwidth synthesis of the subband signals of all channels including the channel excluding only the subband signal band of the overlapping interference band. Has been.

  In the first and second embodiments described above, when the interference wave superimposed on the subband signal is detected, the subband signal to be synthesized with the bandwidth is suppressed in order to suppress the influence of the interference wave when recognizing the target. The subband signal of the interference band is excluded from the band. On the other hand, in the third embodiment of the present invention, the interference wave itself is removed by synthesizing the template waveform of the known frequency used in the existing system with the received signal received on the receiver side. In order to recognize the target, the influence of the interference wave is suppressed.

  FIG. 12 shows a configuration diagram of the broadband radar apparatus 200 of the present embodiment. In FIG. 12, the same components as those shown in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted or simplified. FIG. 13 shows a flowchart of an example of a control routine executed in the broadband radar apparatus 200 of the present embodiment. In FIG. 13, the same steps as those in the routine shown in FIG. 4 are denoted by the same reference numerals, and the description thereof is omitted or simplified.

  That is, in the broadband radar apparatus 200 of the present embodiment, a radar pulse synthesizing circuit 202 is connected to the receiving circuit 34 as shown in FIG. The radar pulse synthesis circuit 202 includes a plurality of AD conversion circuits 48, correlators 50, interference determination circuits 52, interference cancellation circuits 204, and a single bandwidth synthesis circuit 54, respectively. The respective elements 48 to 52 and 204 of the radar pulse synthesizing circuit 202 are provided in the same number as the band-pass filter 44 (that is, the number of subband signals to be obtained by dividing a wideband signal).

A single bandwidth synthesis circuit 54 is connected to the interference determination circuit 52, and a corresponding interference cancellation circuit 204 is connected to each. Each of the interference determination circuits 52 determines whether there is no interference wave for a subband signal in its own band and when it determines that an interference wave exists, the mutual spectrum of the subband signal supplied from the correlator 50. Information on S _k ^v (f _j ) is supplied to the bandwidth synthesis circuit 54 as usual (step 104 and step 300). Further, when it is determined that the interference wave is present, the interference cancellation circuit 204 further notifies an interference cancellation command for notifying that there is an interference wave superimposed on the subband signal in the band and for removing the interference wave. (Step 302).

  Each interference cancellation circuit 204 includes a template waveform of a known frequency that is used in an existing system that is likely to cause radar interference with the broadband radar device 200 in the band of the corresponding subband signal in advance. Is stored as interference wave information that can be superimposed on the subband signal. The template waveform is preferably created in consideration of distortion due to the influence of the propagation path (frequency characteristics of the propagation path).

  When each interference cancellation circuit 204 receives an interference cancellation command from the corresponding interference determination circuit 52, each interference cancellation circuit 204 generates a template waveform representing a signal of a known frequency in the band of the corresponding subband signal from the interference determination circuit 52. The subband signal supplied to the bandwidth synthesis circuit 54 is synthesized (step 304). This synthesis is performed so that the interference wave superimposed on the subband signal supplied from the interference determination circuit 52 to the bandwidth synthesis circuit 54 is cancelled.

According to such a configuration, when no interference occurs, the bandwidth synthesis circuit 54 receives the information on the mutual spectrum S _k ^v (f _j ) of the subband signals from the correlator 50 from all the interference determination circuits 52. When interference is generated while receiving normally, the interference determination circuit 52 covering a band other than the interference band receives information on the mutual spectrum S _k ^v (f _j ) of the subband signal by the correlator 50. Is received as usual, and the information of the mutual spectrum S _k ^v (f _j ) of the subband signal from which the interference wave is canceled is received from the interference determination circuit 52 covering the interference band.

  In this regard, in the present embodiment, when an interference wave is superimposed on a subband signal in a certain band, a likely interference wave is removed from the subband signal in the interference band, and then each subband signal including the subband signal is included. Since the subband signals in the band are synthesized with the bandwidth, the relative distance R to the target can be calculated with a certain degree of accuracy.

  Therefore, according to the wideband radar apparatus 200 of this embodiment, even when an interference band in which an interference wave is superimposed exists and the interference wave is detected, a plurality of subband signals are subjected to bandwidth synthesis to obtain a target. From the subband signal in the interference band that should be used for calculating the relative distance R of the object, it is possible to cancel a plausible interference wave and suppress the influence of the interference wave in recognizing the target Can do. For this reason, in the broadband radar apparatus 200 of the present embodiment, it is possible to calculate the relative distance R to the target while maintaining high accuracy, and the recognition accuracy of the target due to the presence of the interference wave is reduced. It becomes possible to deter, and as a result, the maximum distance at which the target can be recognized can be extended.

  In the third embodiment, the receiving antenna 32, the receiving circuit 34, and the radar pulse synthesizing circuit 202 correspond to the “receiver” recited in the claims, and the interference canceling circuit 204 is compatible. When an interference cancellation command is received from the interference determination circuit 52, a template waveform representing a signal of a known frequency in the band of the corresponding subband signal is supplied from the interference determination circuit 52 to the bandwidth synthesis circuit 54. The “interference suppression means” described in the claims is realized by combining the subband signals.

It is a block diagram of the wideband radar apparatus which is 1st Example of this invention. It is a figure showing the wideband signal used in a present Example, and the subband signal which divided | segmented the wideband signal, respectively. It is a figure showing a mode that an interference wave exists in a part of all the bands of a wideband signal. It is a flowchart of an example of the control routine performed in the wideband radar apparatus of a present Example. It is a figure for demonstrating the method of determining the presence or absence of the interference wave in the zone | band of each subband signal in the broadband radar apparatus of a present Example. It is the table | surface which prescribed | regulated the relationship between the number of elements and the space | interval of adjacent elements as a minimum redundant arrangement | sequence. It is a figure showing arrangement | positioning of the center frequency _fk of each subband signal when the number of the subband signals which should be obtained by dividing | segmenting a wideband signal is four. It is a block diagram of the wideband radar apparatus which is 2nd Example of this invention. It is a specific block diagram of the principal part of the wideband radar apparatus of a present Example. It is a figure for demonstrating the method of excluding only the zone | band of the division | segmentation subband signal with which an interference wave superimposes in the broadband radar apparatus of a present Example from the zone | band which should carry out a bandwidth synthesis | combination. It is a flowchart of an example of the control routine performed in the wideband radar apparatus of a present Example. It is a block diagram of the wideband radar apparatus which is 3rd Example of this invention. It is a flowchart of an example of the control routine performed in the wideband radar apparatus of a present Example.

Explanation of symbols

10, 100, 200 Broadband radar device 12 Signal generator 14 Radar pulse generation circuit 20 Transmission circuit 34 Reception circuit 46, 102, 202 Radar pulse synthesis circuit 50 Correlator 52 Interference determination circuit 54 Bandwidth synthesis circuit 104 Division removal circuit 204 Interference Cancel circuit

Claims (7)

A plurality of subbands having different frequency bands in the reflected waves received by the receiver, the transmitter comprising: a transmitter that transmits a broadband signal; and a receiver that receives a reflected wave of the broadband signal transmitted from the transmitter. A broadband radar device for recognizing a target based on the result of hand width synthesis of a signal,
Interference wave detecting means for detecting an interference wave received by the receiver;
When the interference wave is detected by the interference wave detection means, interference suppression means for suppressing the influence of the interference wave in recognizing the target;
A broadband radar apparatus comprising:   The interference suppression means, when the interference wave is detected by the interference wave detection means, a frequency band in which a bandwidth should be combined for recognizing a target subband signal in a frequency band in which the interference wave exists The wideband radar apparatus according to claim 1, wherein the wideband radar apparatus is excluded from the subband signals. The transmitter is a device that transmits a plurality of subband signals having different frequency bands as a wideband signal,
The interference suppression unit stops transmission of a subband signal in a frequency band in which the interference wave exists from the transmitter when the interference wave is detected by the interference wave detection unit. Item 2. The broadband radar device according to item 1. When the interference wave is detected by the interference wave detecting means, the interference wave exists among a plurality of divided band signals having different frequency bands obtained by dividing the subband signal of the frequency band in which the interference wave exists. A division interference band extraction means for extracting a division band signal of a frequency band is provided,
When the interference wave is detected by the interference wave detection unit, the interference suppression unit recognizes a target of the divided band signal of the frequency band in which the interference wave extracted by the divided interference band extraction unit exists. The wideband radar apparatus according to claim 1, wherein the wideband radar apparatus is excluded from subband signals in a frequency band to be subjected to bandwidth synthesis.   The broadband radar apparatus according to any one of claims 1 to 4, wherein the center frequencies of the subband signals are arranged according to a minimum redundant arrangement.   The interference suppression means receives a template waveform of a frequency corresponding to the interference wave to the receiver so that the influence of the interference wave is suppressed when the interference wave is detected by the interference wave detection means. 2. The broadband radar device according to claim 1, wherein the broadband radar device is synthesized with the reflected wave.   2. The broadband radar apparatus according to claim 1, wherein the interference wave detecting means detects the interference wave based on a correlation between subband signals in each frequency band in a reflected wave received by the receiver. .

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