JPH11237475A - Radar device and detection method for target scattering point in this radar device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To permit detecting target scattering points with resolution below its distance resolution. SOLUTION: Provided is an ultraresolution processor 9 consisting of a correlation matrix calculation means 13 calculating a correlation matrix having elements of mutual correlation value of reception signal, a moving average calculation means 14 constituting submatrixes from parts of the correlation matrix and calculating an averaged correlation matrix from the submatrixes, an eigenvalue analysis means 15 analyzing the eigenvalue of the averaged correlation matrix and obtaining minimum eigenvalue, an evaluation correlation calculation means 16 calculating an evaluation correlation by using the eigenvector calculated from the minimum eigenvalue, a distance estimation means 17 estimating the distance to the scattering points of targets by referring to the peak of amplitude value of the evaluation correlation and using a delay time giving this peak and a reflection intensity estimation means 18 estimating the reflection intensity of the target scattering points by using the estimated value of the delay time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention tracks a target object, for example, an aircraft, transmits a plurality of pulses whose frequency is changed stepwise with respect to the target, and scatters the target from the received pulses. The present invention relates to a radar device for detecting points and a method for detecting a target scattering point in the radar device.

[0002]

2. Description of the Related Art Conventionally, as this type of radar device, there is, for example, one shown in High Resolution Radar (by DR Wehner, 1987). FIG. 11 shows an example of a conventional radar device disclosed in the above-mentioned document. It is a block diagram.

In the figure, 1 is a transmitter for transmitting a plurality of pulses, 2 is a step frequency oscillator for outputting a signal whose frequency is set based on a frequency control signal inputted from a control circuit 4 described later, and 3 is a transmitter This is a pulse modulator that generates a trigger signal for the signal 1.

[0004] Reference numeral 5 denotes a transmission / reception switch for switching between transmission and reception, 6 denotes an antenna which radiates a plurality of pulses transmitted from the transmitter 1 via the transmission / reception switch 5 to space, and receives a pulse reflected from a target. Is a receiver that receives a pulse from the antenna 6 and outputs it as a received signal, 8 is a memory that stores a received signal from the receiver 7, and 22 is a target scattering point based on data read from the memory 8. It is a target scattering point detector to be detected. The control circuit 4 outputs a frequency control signal to the step frequency oscillator 2 and outputs transmission frequency data to the memory 8. Reference numeral 10 denotes a signal processor including the control circuit 4, the memory 8, and the target scattering point detector 22.

Next, the operation of this conventional radar device will be described. The step frequency oscillator 2 outputs a signal whose frequency is set based on the frequency control signal input from the control circuit 4. The control circuit 4 controls the frequency control signal so that the frequency changes stepwise for each pulse, and outputs the signal to the step frequency oscillator 2. At this time,
The frequency F of the pulse transmitted the second time is expressed by the following equation (1), where Fo is the initial frequency value and ΔF is the frequency step value.
Is set based on

[0006]

(Equation 1)

[0007] The transmitter 1 amplifies the output of the step frequency oscillator 2 and generates and outputs a pulse in synchronization with the transmission trigger signal of the pulse modulator 3. The pulse output from the transmitter 1 is supplied to the antenna 6 via the transmission / reception switch 5 and is radiated from the antenna 6 to space. Then, the antenna 6 receives the pulse reflected from the target and outputs the pulse to the receiver 7 via the transmission / reception switch 5. The pulse input to the receiver 7 is frequency-converted into a video signal, phase-detected and digital-converted, and output to the signal processor 10 as a received signal.

The signal processor 10 stores the received signal in the memory 8 together with the transmission frequency data input from the control circuit 4 for each pulse. Next, the signal processor 10 reads the received signal stored in the memory 8 for each transmission frequency, and outputs these data to the target scattering point detector 22. The target scattering point detector 22 performs an inverse Fourier transform process on the input received signal to synthesize a target range profile. At this time, the detection of the target scattering point is performed based on the range profile under the distance resolution ΔR given by the following equation (2), where ΔF is the frequency step value of the transmitted pulse, M is the number of pulses, and c is the speed of light. This is performed by detecting the peak of

[0009]

(Equation 2)

As described above, a plurality of pulses whose frequency is changed stepwise are transmitted, and the target scattering point can be detected from the pulse reflected from the target.

[0011]

Since the conventional radar apparatus is configured as described above, it is impossible to detect a target scattering point with a resolution equal to or less than the distance resolution ΔR given by the above equation (2). There was a problem.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a radar apparatus and a radar capable of detecting a target scattering point with a resolution not more than a distance resolution defined by a transmission frequency band. It is intended to obtain a method for detecting a target scattering point in an apparatus.

[0013]

According to a first aspect of the present invention, a radar apparatus tracks a target, acquires distance information, and transmits a plurality of pulses whose frequency is changed stepwise with respect to the target. Then, after receiving the pulses reflected from the target, frequency-converting these received pulses into video signals, a radar device that detects the target scattering point from the digitally-converted received signals, and calculates the average calculated from the received signals The distance to the target scattering point based on the delay time that gives the peak of the amplitude value of the evaluation function with respect to the minimum eigenvalue of the correlation matrix, and the reflection intensity of the target scattering point based on the estimated value of the delay time, It is equipped with a super-resolution processor for detecting scattering points.

According to a second aspect of the present invention, in the radar apparatus according to the first aspect, the super-resolution processor calculates a correlation matrix having a cross-correlation value of a received signal as an element. A moving average calculating means for forming a sub-matrix from a part of the correlation matrix and calculating an average correlation matrix from a moving average of these sub-matrices; and an eigenvalue analyzing means for performing eigenvalue analysis of the average correlation matrix to obtain a minimum eigenvalue And an evaluation function calculating means for calculating an evaluation function using an eigenvector calculated from the minimum eigenvalue, and searching for a peak of the amplitude value of the evaluation function, and calculating a peak time from a delay time for providing the peak to the target scattering point. It has a distance estimating means for estimating the distance and a reflection intensity estimating means for estimating the reflection intensity of the target scattering point by using the estimated value of the delay time.

According to a third aspect of the present invention, in the radar apparatus according to the second aspect, the correlation matrix calculating means is configured to calculate only a diagonal term of the correlation matrix.

According to a fourth aspect of the present invention, in the radar apparatus according to the second aspect, the correlation matrix calculating means is configured to calculate a correlation matrix by averaging a plurality of received signals of the same frequency. is there.

According to a fifth aspect of the present invention, there is provided a radar apparatus according to the second aspect, wherein the distance estimating means sets the delay search in which a peak search of the amplitude value of the evaluation function is set based on the acquired target distance information. This is configured to be performed within the time prediction range.

According to a sixth aspect of the present invention, in the radar apparatus according to the second aspect, the reflection intensity estimating means uses a sub-matrix constituted by the moving average calculating means to obtain a reflection intensity of a target scattering point. Is calculated.

According to a seventh aspect of the present invention, in the radar apparatus according to the second aspect, the reflection intensity estimating means uses a plurality of sub-matrices constituted by the moving average calculating means to reflect a target scattering point. It is configured to calculate the reflection intensity.

According to a eighth aspect of the present invention, there is provided a method for detecting a target scattering point in a radar apparatus, which tracks a target, acquires distance information, and transmits a plurality of pulses whose frequency is changed stepwise with respect to the target. Then, after receiving the pulses reflected from the target, converting the frequency of these received pulses into a video signal, and then detecting the target scattering point from the digitally converted received signal, the target scattering point detection method in the radar apparatus. A first step of calculating a correlation matrix having a cross-correlation value of a received signal as an element, forming a sub-matrix from a part of the correlation matrix, and calculating an average correlation matrix from a moving average of these sub-matrices A second step, a third step of performing an eigenvalue analysis of the average correlation matrix to obtain a minimum eigenvalue, and an evaluation using the eigenvector calculated from the minimum eigenvalue A fourth step of calculating the function;
A fifth step of retrieving the peak of the amplitude value of the evaluation function and estimating the distance from the delay time at which the peak is present to the target scattering point; and And a sixth step of estimating the reflection intensity of the scattering point.

According to a ninth aspect of the present invention, in the method of detecting a target scattering point in the radar apparatus according to the eighth aspect, a step of calculating only a diagonal term of the correlation matrix is used instead of the first step. Things.

According to a tenth aspect of the present invention, in the method for detecting a target scattered point in the radar apparatus according to the eighth aspect, instead of the first step, a correlation matrix is averaged by averaging a plurality of received signals of the same frequency. The calculation step is used.

According to an eleventh aspect of the present invention, there is provided a method for detecting a target scattering point in a radar apparatus according to the eighth aspect, wherein a peak search for the amplitude value of the evaluation function is performed instead of the fifth step. Is performed in a delay time prediction range set based on the distance information.

According to a twelfth aspect of the present invention, there is provided a method for detecting a target scattering point in a radar apparatus according to the eighth aspect, wherein the sub-matrix is used instead of the sixth step.
The step of calculating the reflection intensity of the target scattering point is used.

According to a thirteenth aspect of the present invention, there is provided a method for detecting a target scattered point in a radar apparatus according to the eighth aspect of the present invention, wherein a plurality of the sub-matrices are used instead of the sixth step. The step of calculating the reflection intensity is used.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. Embodiment 1 FIG. FIG. 1 is a configuration diagram showing Embodiment 1 of the present invention. In the figure, parts corresponding to those in FIG. 11 are denoted by the same reference numerals, and detailed description thereof will be omitted. Reference numeral 10A denotes a signal processor according to the present embodiment, which includes a super-resolution processor 9 in addition to the control circuit 4 and the memory 8 described above.

FIG. 2 is a block diagram showing an example of a specific circuit configuration of the super-resolution processor 9. In the figure, reference numeral 13 denotes a correlation matrix calculating means for calculating a correlation matrix having a cross-correlation value of a received signal as an element, and 14 constitutes a sub-matrix from a part of the correlation matrix calculated by the correlation matrix calculating means 13. A moving average calculating means for calculating an average correlation matrix from a moving average of the sub-matrices; a eigenvalue analyzing means for performing an eigenvalue analysis of the average correlation matrix calculated by the moving average calculating means to obtain a minimum eigenvalue; Evaluation function calculating means for calculating an evaluation function using the eigenvector calculated from the minimum eigenvalue obtained in 15;
6. Search for the peak of the amplitude value of the evaluation function calculated in 6, and
Distance estimating means for estimating the distance to the target scattering point from the delay time at which the peak is given;
3 is a reflection intensity estimating means for estimating the reflection intensity of the target scattering point based on the correlation matrix from No. 3, the minimum eigenvalue from the eigenvalue analyzing means 15, and the delay time from the distance estimating means 17.

Next, the operation will be described with reference to FIGS. First, as shown in FIG.
Transmits a plurality of pulses to the front target 11 consisting of K scattering points while changing the frequency in a stepwise manner.
Consider a situation in which pulses reflected from 1 are received by the antenna 6 and a scattered point of the target 11 is detected from these pulses.

The process of detecting a target scattering point performed by the super-resolution processor 9 at this time will be described with reference to FIGS. 4 and 5. The correlation matrix calculation means 13 reads the received signal x _M (N) stored in the memory 8 for each transmission frequency, and calculates a correlation matrix R defined by the following equation (3). Here, the suffix _M of the received signal x _M (N) represents the M-th transmission frequency given by the equation (1), and the variable N is the N-th reception frequency when a plurality of pulses of the same frequency are transmitted. Corresponds to the pulse. In the present embodiment, a single pulse of the same frequency is transmitted, and equation (3) is modified with N = 1. In equation (3), * represents a conjugate complex number.

[0030]

(Equation 3)

[0031]

[Outside 1]

[0032]

(Equation 4)

[0033]

[Outside 2]

[0034]

(Equation 5)

Here, the eigenvalue analysis means 15 determines the number of eigenvalues greater than the minimum eigenvalue λ _min (= λ _{k + 1} = λ _{k + 2} =... = Λ M ₀ ) as the number K of target scattering points. presume. next,
The evaluation function calculation means 16 calculates an eigenvector en = [ek + 1,..., EM ₀ ] corresponding to the minimum eigenvalue λm (m = k + 1,..., M ₀ ) obtained by the eigenvalue analysis means 15.
And the propagation delay time vector (t _k ) given by the following equation (6), the evaluation function P defined by the following equation (7)
(T) is calculated. Here, t _k is the delay time, F ₀ is the frequency initial value, [Delta] F is the frequency step value, T is the transpose of a vector, M ₀ is the order of the sub-matrix, H is representative of a complex conjugate transpose, respectively.

[0036]

(Equation 6)

[0037] Then the distance estimating means 17, the peak amplitude value of the evaluation function 21 as shown in FIG. 5, to find the origin, we obtain the delay time t _k that gives a peak. Further, the distance estimation unit 17, by the following equation (8), the distance from the radar apparatus to each scattering point of the target r _{k (k} = 1,2, ··
, K) is calculated.

[0038]

(Equation 7)

Next, the reflection intensity estimating means 18 calculates the propagation delay time vector a (t _k ) defined by the following equation (9):
The matrix A defined by the following equation (10) is calculated by substituting the delay time t _k input from the distance estimating means 17. Here, t _k is the delay time, F ₀ is the frequency initial value, delta
F represents the frequency step value, T represents the transposition of the vector, and M ₀ represents the order of the correlation matrix.

[0040]

(Equation 8)

Further, the reflection intensity estimating means 18 calculates a matrix S from the matrix A, the correlation matrix R, the minimum eigenvalue λ _min , and the unit matrix I of M × M by the following equation (11).

[0042]

(Equation 9)

The reflection intensity estimating means 18 estimates the reflection intensity of each target scattering point from the diagonal term of the calculated matrix S. In this way, the super-resolution processor 9 determines the target based on the distance to each target scattering point estimated by the distance estimating means 17 and the reflection intensity of each target scattering point estimated by the reflection intensity estimating means 18. Detect scattering points. When a target scattering point is detected by such a method, for example, the known document Multi
pleEmitter Location and Signal Parameter Estimatio
n (by ROSchmidt, IEEE Trans.AP-34, 3, pp.276-280
(1986)) shows that a target scattering point can be detected with a resolution equal to or less than the distance resolution defined by the above equation (2).

As described above, in the present embodiment,
By performing the above-described processing, a target scattering point can be detected with a resolution equal to or less than the distance resolution defined by the above equation (2).

Embodiment 2 In the correlation matrix calculating means 13 shown in the first embodiment, as shown in FIG. 6, only the diagonal terms of the correlation matrix 19 used when the moving average calculating means 14 forms the sub-matrix 20 are used. Thus, the correlation matrix 19 may be calculated. This allows
The amount of calculation of the correlation matrix 19 in the correlation matrix calculation means 13 can be reduced.

Embodiment 3 Further, the correlation matrix calculating means 13 shown in the first embodiment may calculate the correlation matrix 19 by averaging a plurality of received signals of the same frequency as shown in FIG. At this time, the correlation matrix calculation means 13 calculates the correlation matrix R by the following equation (12).
Is calculated. Thereby, the calculation accuracy of the correlation matrix can be improved.

[0047]

(Equation 10)

Embodiment 4 Further, as shown in FIG. 8, the peak search of the amplitude value of the evaluation function 21 in the distance estimating unit 17 shown in the first embodiment is performed in the delay time prediction range set based on the acquired target distance information. It may be performed. Thereby, the amount of calculation in the distance estimating means 17 can be reduced.

Embodiment 5 Further, the calculation of the reflection intensity of the scattering point in the reflection intensity estimating means 18 shown in the first embodiment is performed using one of the sub-matrices constituted by the moving average calculating means 14 as shown in FIG. Is also good.

[Outside 3]

[0050]

[Equation 11]

The reflection intensity estimating means 18 calculates the calculated matrix S
From the diagonal terms of, the reflection intensity of each target scattering point is estimated.
Thus, the amount of calculation in the reflection intensity estimating means 18 can be reduced.

Embodiment 6 FIG. Further, the calculation of the reflection reflection intensity of the target scattering point in the reflection intensity estimation means 18 shown in the first embodiment is performed using a plurality of sub-matrices constituted by the moving average calculation means 14 as shown in FIG. It may be.

[Outside 4]

[0053]

As described above, according to the first aspect of the present invention, the target scattering point based on the delay time that gives the peak of the amplitude value of the evaluation function with respect to the minimum eigenvalue of the average correlation matrix calculated from the received signal. Since a super-resolution processor that detects a target scattering point from the distance and the reflection intensity of the target scattering point based on the estimated value of the delay time is provided, it is defined by the transmission frequency band, that is, the above equation (2) This has the effect that the target scattering point can be detected with a resolution equal to or less than the distance resolution specified in (2).

According to the second aspect of the present invention, the super-resolution processor includes: a correlation matrix calculating means for calculating a correlation matrix having a cross-correlation value of a received signal as an element; A sub-matrix, a moving average calculating means for calculating an average correlation matrix from a moving average of these sub-matrices, an eigenvalue analyzing means for performing an eigenvalue analysis of the average correlation matrix to obtain a minimum eigenvalue, An evaluation function calculating means for calculating an evaluation function using the distance function; a distance estimating means for searching for a peak of an amplitude value of the evaluation function and estimating a distance from a delay time giving the peak to a target scattering point; And a reflection intensity estimating means for estimating the reflection intensity of the target scattering point using the estimated value, so that the reflection intensity is defined by the transmission frequency band, that is, the distance resolution equal to or less than the distance resolution defined by the above equation (2). There is an effect that the target scattering points can be detected accurately with the image of.

According to the third aspect of the present invention, the correlation matrix calculating means is configured to calculate only the diagonal terms of the correlation matrix. There is an effect that the amount of calculation of the calculating means can be reduced.

According to the fourth aspect of the present invention, the correlation matrix calculating means is configured to calculate a correlation matrix by averaging a plurality of received signals of the same frequency.
In addition to the effect of the invention of (1), there is an effect that the calculation accuracy of the correlation matrix can be improved.

According to the fifth aspect of the present invention, the distance estimating means performs the peak search of the amplitude value of the evaluation function within the delay time prediction range set based on the acquired target distance information. With the configuration, in addition to the effect of the second aspect of the invention, there is an effect that the amount of calculation of the distance estimating means can be reduced.

According to the invention of claim 6, the reflection intensity estimating means is configured to calculate the reflection reflection intensity of the target scattering point by using the sub-matrix constituted by the moving average calculating means. In addition to the effects of the invention of claim 2, there is an effect that the amount of calculation of the reflection intensity estimating means can be reduced.

According to the invention of claim 7, the reflection intensity estimating means is configured to calculate the reflection reflection intensity of the target scattering point by using a plurality of sub-matrices constituted by the moving average calculating means. Therefore, in addition to the effect of the invention of claim 2, there is an effect that the calculation accuracy of the reflection intensity estimating means can be improved.

According to the invention of claim 8, a first step of calculating a correlation matrix having a cross-correlation value of a received signal as an element, and forming a sub-matrix from a part of the correlation matrix, A second step of calculating an average correlation matrix from a moving average of the sub-matrix of the above, a third step of performing eigenvalue analysis of the average correlation matrix to obtain a minimum eigenvalue, and calculating an evaluation function using an eigenvector calculated from the minimum eigenvalue A fourth step of searching for a peak of the amplitude value of the evaluation function, and a fifth step of estimating a distance to a target scattering point from a delay time at which the peak is obtained, and an estimated value of the delay time. And a sixth step of estimating the reflection intensity of the target scattering point, so that the
That is, there is an effect that the target scattering point can be accurately detected with a resolution equal to or less than the distance resolution defined by the above equation (2).

According to the ninth aspect of the present invention, the first
Since the step of calculating only the diagonal term of the correlation matrix is used instead of the step of (1), in addition to the effect of the invention of claim 8, the amount of calculation in calculating the correlation matrix is reduced, and There is an effect that detection can be performed.

According to the tenth aspect of the present invention, instead of the first step, a step of calculating a correlation matrix by averaging a plurality of received signals of the same frequency is used. In addition to the effects, there is an effect that the calculation accuracy of the correlation matrix can be improved and the detection accuracy can be improved.

According to the eleventh aspect of the present invention, instead of the fifth step, the peak search of the amplitude value of the evaluation function is performed in the prediction range of the delay time set based on the acquired target distance information. Claim 8 uses the performing step.
In addition to the effects of the present invention, there is an effect that the amount of calculation at the time of distance estimation is reduced, and the target scattering point can be quickly detected.

According to the twelfth aspect of the present invention, instead of the sixth step, the step of calculating the reflection intensity of the target scattering point using the sub-matrix is used.
In addition to the effect of the eighth aspect of the present invention, there is an effect that the calculation amount at the time of estimating the reflection intensity is reduced, and the target scattering point can be detected quickly.

According to the thirteenth aspect, a plurality of sub-matrices are used instead of the sixth step.
Since the step of calculating the reflection reflection intensity of the target scattering point is used, there is an effect that, in addition to the effect of the invention of claim 8, the calculation accuracy at the time of reflection intensity estimation and the detection accuracy can be improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a radar apparatus according to Embodiment 1 of the present invention.

FIG. 2 is a block diagram showing a super-resolution processor according to Embodiment 1 of the present invention.

FIG. 3 is an explanatory diagram showing a relationship between a radar device and a target.

FIG. 4 is an explanatory diagram showing a relationship between a correlation matrix and a sub-matrix according to Embodiment 1 of the present invention.

FIG. 5 is an explanatory diagram of peak search of an evaluation function according to the first embodiment of the present invention.

FIG. 6 is an explanatory diagram showing a relationship between a correlation matrix and a sub-matrix according to Embodiment 2 of the present invention.

FIG. 7 is an explanatory diagram showing a relationship between a correlation matrix and a sub-matrix according to Embodiment 3 of the present invention.

FIG. 8 is an explanatory diagram of peak search of an evaluation function according to Embodiment 4 of the present invention.

FIG. 9 is a block diagram illustrating a super-resolution processor according to a fifth embodiment of the present invention.

FIG. 10 is a block diagram showing a super-resolution processor according to a sixth embodiment of the present invention.

FIG. 11 is a configuration diagram showing a conventional radar device.

[Explanation of symbols]

1 transmitter, 2 step frequency oscillator, 3 pulse modulator, 4 control circuit, 5 duplexer, 6 antenna,
Reference Signs List 7 receiver, 8 memory, 9, 9A, 9B super-resolution processor, 10, 10A signal processor, 11 target, 12 radar device, 13 correlation matrix calculation means, 14 moving average calculation means, 15 eigenvalue analysis means, 16 Evaluation function calculation means, 17 distance estimation means, 18 reflection intensity estimation means,
19 correlation matrix, 20 sub-matrix, 21 evaluation function,
22 Target scattering point detector.

Claims (13)

[Claims] 1. A target is tracked, distance information is acquired, a plurality of pulses whose frequency is changed stepwise with respect to the target are transmitted, and a pulse reflected from the target is received. In a radar device for converting a received pulse into a video signal and then detecting the target scattering point from the digitally converted received signal, a peak of an amplitude value of an evaluation function for a minimum eigenvalue of an average correlation matrix calculated from the received signal is given. A distance to the target scattering point based on the delay time, and a super-resolution processor for detecting the target scattering point from the reflection intensity of the target scattering point based on the estimated value of the delay time. Characteristic radar device. 2. The super-resolution processor comprises: a correlation matrix calculating means for calculating a correlation matrix having a cross-correlation value of a received signal as an element; and a sub-matrix comprising a part of the correlation matrix. Moving average calculation means for calculating an average correlation matrix from the moving average of the sub-matrix, eigenvalue analysis means for performing eigenvalue analysis of the average correlation matrix to obtain a minimum eigenvalue, and calculating an evaluation function using the eigenvector calculated from the minimum eigenvalue Evaluation function calculating means, a distance estimating means for searching for a peak of the amplitude value of the evaluation function, and estimating a distance to the target scattering point from a delay time at which this peak is obtained, and calculating the estimated value of the delay time. 2. The radar apparatus according to claim 1, further comprising: reflection intensity estimating means for estimating the reflection intensity of the target scattering point. 3. The radar apparatus according to claim 2, wherein said correlation matrix calculation means is configured to calculate only diagonal terms of said correlation matrix. 4. The radar apparatus according to claim 2, wherein said correlation matrix calculation means is configured to calculate a correlation matrix by averaging a plurality of received signals of the same frequency. 5. The method according to claim 1, wherein the distance estimating means is configured to perform a peak search for the amplitude value of the evaluation function in a prediction range of a delay time set based on the acquired target distance information. Item 3. The radar device according to item 2. 6. The apparatus according to claim 2, wherein said reflection intensity estimating means is configured to calculate a reflection reflection intensity of a target scattering point using a sub-matrix constituted by said moving average calculating means. Radar equipment. 7. The apparatus according to claim 1, wherein said reflection intensity estimating means is configured to calculate a reflection reflection intensity of a target scattering point using a plurality of sub-matrices formed by said moving average calculating means. 2. The radar device according to 2. 8. A target is tracked, distance information is obtained, a plurality of pulses whose frequency is changed stepwise with respect to the target are transmitted, and pulses reflected from the target are received. In a target scattering point detection method in a radar apparatus for detecting a target scattering point from a digitally converted reception signal after frequency conversion of a reception pulse into a video signal, calculation of a correlation matrix using a cross-correlation value of the reception signal as an element A second step of forming a sub-matrix from a part of the correlation matrix and calculating an average correlation matrix from a moving average of these sub-matrices; and performing an eigenvalue analysis of the average correlation matrix A third step of obtaining a minimum eigenvalue, a fourth step of calculating an evaluation function using the eigenvector calculated from the minimum eigenvalue, and a peak of the amplitude value of the evaluation function. A fifth step of estimating the distance to the target scattering point from the delay time at which the peak is obtained, and estimating the reflection intensity of the target scattering point using the estimated value of the delay time. A target scattering point detection method in the radar apparatus. 9. The method according to claim 8, wherein a step of calculating only a diagonal term of the correlation matrix is used instead of the first step. 10. The method according to claim 8, wherein a step of averaging a plurality of received signals of the same frequency to calculate a correlation matrix is used instead of the first step. Method. 11. The method according to claim 6, wherein a step of performing a peak search for the amplitude value of the evaluation function in a prediction range of a delay time set based on the acquired target distance information is used instead of the fifth step. The method for detecting a target scattering point in the radar apparatus according to claim 8. 12. The target scattering in the radar apparatus according to claim 8, wherein a step of calculating the reflection intensity of the target scattering point using the sub-matrix is used instead of the sixth step. Point detection method. 13. The radar apparatus according to claim 8, wherein, instead of the sixth step, a step of calculating the reflection intensity of the target scattering point using a plurality of the sub-matrices is used. Method for detecting a target scattering point.