JPH07159515A - Processing method for radar signal - Google Patents

Abstract

PURPOSE:To make it possible to carry out optimum target detection by controlling the threshold of a bearing filter according to information derived from a calculating portion for the spread of the bearing of a target for detection, so that only the target for detection passes through the filter. CONSTITUTION:A quantizer portion 1 quantizes analog-received video signals using a method such as CFAR. The signals quantized are subjected to stepped integrations by a bearing filter portion 2 and then to bearing range detection by a sliding window, etc. In order to control the threshold of the filter 2, a calculating portion 4 for the bearing spread of a target for detection calculates the spread of the bearing from the dimension at that position of the subject for detection, according to position information. The spread of bearing gets broader naturally in the case of a short distance. A threshold control portion 5 controls the threshold of the filter 2 according to information about the spread of bearing so that only the target for detection passes through it. Optimum target detection is thus made possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal processing method in a radar such as an airport surface detection radar where the size of a target to be detected may be wider than the beam width.

[0002]

2. Description of the Related Art FIG. 7 is a block diagram of a conventional radar signal processing system. In the figure, 1 is an analog received video quantizer, and 2 is a check of the azimuth continuity of the quantized received video. The azimuth direction filter unit 3, 3 is an integration unit that collects the signals that have passed through the azimuth direction filter unit 2 as one target, 7 is a target determination unit that checks whether the targets integrated by the integration unit 3 are to be detected, and 16 is The inter-scan correlation unit that associates the signals determined as the target by the target determination unit 7 between the scans, 17 is the smoothing of the detection position,
This is a tracking calculation unit that calculates the predicted position of the next scan.

Next, the operation will be described. The analog reception video is quantized by the quantizer 1 by a method such as CFAR. The quantized signal is subjected to the azimuth continuity test by the stepwise integration, sliding window, etc. in the azimuth direction filter unit 2, and only the signal that exceeds a certain threshold is passed. The signals that have passed through the azimuth direction filter 2 are combined by the integration unit 3 into received signals from the same target. The target determining unit 7 checks whether the azimuth-direction spread and the distance-direction spread of the targets combined by the integrating unit 3 are within a certain threshold range, and determines whether the targets are detection targets. The target determined to be the detection target is associated with each other by the inter-scan correlation unit 16, and the tracking calculation unit 17 uses the information of the target regarded as the same target between the scans. Position smoothing, calculation of a predicted position for the next scan, and the like are performed.

[0004]

Since the conventional radar signal processing system is constructed as described above, the azimuth direction filter and the target judgment threshold cannot be adaptively controlled, and the size of the target to be detected is smaller than that of the beam. There is a problem that it is difficult to optimally detect a target in a radar that may be wider than the width.

The present invention has been made to solve the above problems, and an object of the present invention is to obtain a radar signal processing system which adaptively controls each threshold and enables optimum target detection. And

[0006]

A radar signal processing system according to claim 1, wherein a quantized part for quantizing a received video and an azimuth direction filter for carrying out an azimuth direction continuous test of the signal quantized by this quantizer part. Section, the detection target target azimuth spread calculation unit that calculates the spread in the azimuth direction from the size of the detection target target based on the position information, and only the detection target target is passed using the information of the detection target target azimuth spread calculation unit. A threshold control unit for controlling the threshold value of the azimuth direction filter unit is provided, and an integration unit for collecting the signals passed through the azimuth direction filter unit as one target.

A radar signal processing method according to a second aspect is the radar signal processing method according to the first aspect, in which the number of signals passed through the azimuth direction filter section is accumulated and the result is fed back to a threshold control section. It has a number accumulator.

In the radar signal processing method according to a third aspect of the present invention, an integration unit that collects signals that have passed through the azimuth direction filter unit as one target, a position calculation unit that calculates a position from the output signal of the integration unit, and this position calculation unit. The target detection target distance / azimuth spread calculation unit that calculates the spread in the distance direction and azimuth direction of the detection target target at the position calculated by, and the detection target target based on the information of the detection target target distance / direction spread calculation unit A threshold control unit that controls the threshold of the target determination so that only the target is passed, and a target determination unit that determines and outputs the target to be detected using this threshold,
It is equipped with.

A radar signal processing system according to a fourth aspect of the present invention is the radar signal processing system according to the third aspect, in which the target number accumulating unit for accumulating the number of targets passing through the target determining unit and feeding back the result to the threshold control unit. It is equipped with.

According to a fifth aspect of the radar signal processing method of the present invention, a quantizer for quantizing the received video, an elevation direction filter unit for performing an elevation direction concatenation test on the signal quantized by the quantizer, and position information Based on the detection target target elevation angle spread calculation unit that calculates the spread in the elevation angle direction based on the size of the detection target target, the elevation direction so that only the detection target target passes using the information of the detection target target elevation angle spread calculation unit A first threshold control unit that controls the threshold of the filter unit, an azimuth direction filter unit that performs azimuth direction continuity verification of the signal that has passed through the elevation angle direction filter unit, and the size of the target to be detected based on the position information. Only the detection target target azimuth spread calculation unit that calculates the azimuth spread and the detection target target azimuth spread calculation unit are used to pass only the detection target target. Wherein the second threshold control unit for controlling the threshold azimuthal filter unit, those having the a.

According to a sixth aspect of the radar signal processing method of the present invention, there is provided a tracking target determination section for determining a tracking target of the target based on the target information, and an inter-scan correlation section for obtaining an inter-scan correlation based on the result of the tracking target determination section. A tracking calculation unit that performs tracking calculation based on the result of the inter-scan correlation unit, a processing load calculation unit that obtains a processing load of the tracking calculation unit and the inter-scan correlation unit, and the processing load calculation unit based on the result of the processing load calculation unit. And a threshold control unit that performs threshold control of the tracking target determination unit.

[0012]

According to the radar signal processing method of the present invention, the threshold control unit controls the threshold of the azimuth direction filter so that only the detection target is allowed to pass, based on the information of the detection target target azimuth spread calculation unit. It can detect various targets.

In the radar signal processing system according to the second aspect, the result of the filter passing signal number accumulating unit is fed back to the threshold control unit to perform the threshold control, so that the processing load after the azimuth direction filter unit does not become excessive.

In the radar signal processing method according to the third aspect of the present invention, the threshold control unit controls so that only the target to be detected is allowed to pass, so that optimum target detection can be performed.

According to the radar signal processing method of the fourth aspect, since the result of the target accumulating unit is fed back to the threshold control unit to perform the threshold control, the processing load after the target determining unit does not become excessive.

According to the radar signal processing method of the fifth aspect, the first and second radar signal processing methods are based on the outputs of the detection target target elevation angle spread calculation section which receives the position information and the detection target target azimuth direction spread calculation section which receives the position information. Since the threshold control unit controls the elevation angle filter and the azimuth direction filter so that only the target to be detected is passed, optimum target detection can be performed.

According to the radar signal processing method of the sixth aspect, the processing load of the inter-scan correlation and the tracking calculation is obtained, and only the targets with high priorities are tracked when overloaded.

[0018]

【Example】

Example 1. Embodiment 1 of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 1 is an analog received video quantizer, 2 is an azimuth direction filter unit that checks the azimuth direction continuity of the received video quantized by the quantization unit 1, and 3 is an azimuth direction filter unit 2. The integrated unit 4 which collects the generated signals as one target, the position-based detection target target azimuth spread calculation unit 5 and the detection target target azimuth spread calculation unit 4 correspond to the detection target target azimuth spread calculation unit 4 It is a department.

Next, the operation will be described. The quantizer 1 quantizes the analog received video by a method such as CFAR. The quantized signal is subjected to the azimuth continuity test in the azimuth direction filter unit 2 by stepwise integration, sliding window, or the like. In order to perform the threshold control of this filter, the detection target target azimuth spread calculation unit 4 calculates the spread in the azimuth direction from the size of the detection target target at the position based on the position information (the target is a beam). If it is larger than the width, naturally, the azimuth spread increases at a short distance). Using this information, the threshold control unit 5 passes only the target to be detected,
Controls the filter threshold.

As described above, according to the first embodiment, the threshold of the azimuth direction filter 2 is controlled by the threshold control unit based on the information of the detection target target azimuth spread calculation unit 4 so as to pass only the detection target. Because
Optimal target detection is possible.

Example 2. A second embodiment of the present invention will be described with reference to FIG. FIG. 2 further shows an azimuth direction filter unit 2
The function of controlling the threshold of the filter is added according to the number of signals passing through the filter. In the figure, 1 to 4 are the same as those in FIG. 1, but a filter passing signal number accumulating section 6 is added. The result is fed back to the threshold control unit 5 to perform threshold control so that the processing load after the azimuth direction filter unit 2 does not become excessive.

According to the second embodiment, the filter passing signal number accumulating unit 6 is provided, and the result is obtained by the threshold control unit 5.
Feedback control to perform threshold control,
The processing load after the azimuth direction filter unit 2 does not become excessive.

Example 3. A third embodiment of the present invention will be described with reference to the drawings. FIG. 3 is for performing threshold control in target determination. In the integration unit 3, the position detection unit 8 calculates the position of the signals combined as one target, and the detection target distance / azimuth spread calculation unit 9 calculates The threshold of the target determination is controlled by the threshold control unit 10 so that only the detection target is allowed to pass through based on this information, and the target determination threshold is controlled by the target determination unit 7. Using this threshold, it is determined whether or not the target is the detection target, and only when it is determined to be the detection target, the target is output.

According to the third embodiment, since the threshold control unit 10 controls so that only the target to be detected passes, it is possible to optimally detect the target.

Example 4. A fourth embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a diagram in which a function for performing threshold control for target determination is added to FIG. 3 according to the number of targets that have passed through the target determination unit. In FIG. 4, 3, 7 to 9 are the same as those in FIG. The target number accumulating unit 11 is added and the result is fed back to the threshold control unit 10 to perform threshold control so that the processing load after the target determining unit 7 does not become excessive.

According to the fourth embodiment, the target number accumulation unit 11
Is added, and the result is fed back to the threshold control unit 10 to perform threshold control, so that the processing load after the target determination unit does not become excessive.

Example 5. A fifth embodiment of the present invention will be described with reference to the drawings. FIG. 5 shows a configuration corresponding to the three-dimensional radar of FIG. 1, and an elevation angle direction filter 12 is added. In the figure,
1, 2, 4, and 5 are the same as those in FIG. 1, except that the elevation angle filter unit 12 and the elevation angle filter threshold control unit 1 are provided.
3, the detection target target elevation angle spread calculation unit 14 is added.

According to the fifth embodiment, the threshold control unit determines only the detection target based on the detection target that receives position information and the outputs of the elevation angle spread calculation unit 14 and the detection target target azimuth spread calculation unit 4. Since the elevation angle filter 12 and the azimuth direction filter 2 are controlled so as to pass, optimum target detection is possible.

Example 6. A sixth embodiment of the present invention will be described with reference to the drawings. FIG. 6 shows a case in which a target to be tracked is determined according to the processing load when the target is subjected to inter-scan correlation and tracking calculation. When the target is overloaded, only the target having a high priority is tracked. is there. 16, 1 in the figure
7 is the same as the conventional example of FIG. 7, but the processing load calculation unit 19
By calculating the correlation between scans and the processing load of tracking calculation,
Based on this, the threshold control unit 18 for determining the tracking target performs threshold control in consideration of the target position and the like, and only the target that has passed the tracking target determination unit 15 is subjected to inter-scan correlation and tracking calculation.

According to the sixth embodiment, the processing load calculation unit 1
The correlation between scans and the processing load of tracking calculation are calculated by
At the time of overload, tracking is performed only for targets with high priority.

[0031]

According to the radar signal processing method of the present invention, the quantizer for quantizing the received video, the azimuth direction filter unit for performing the azimuth direction concatenation test of the signal quantized by the quantizer, and the position Based on the information, the detection target target azimuth spread calculation unit that calculates the spread in the azimuth direction from the size of the detection target target, and using the information of this detection target target azimuth spread calculation unit to pass only the detection target target Since the threshold control unit that controls the threshold of the azimuth direction filter unit and the integration unit that collects the signals that have passed through the azimuth direction filter unit as one target, the information of the target azimuth spread calculation unit to be detected On the basis of,
Since the threshold of the azimuth direction filter is controlled by the threshold control unit so that only the target to be detected is passed, optimum target detection can be performed.

A radar signal processing system according to a second aspect is the radar signal processing system according to the first aspect, in which the number of signals passed through the azimuth direction filter unit is accumulated and the result is fed back to a threshold control unit. Since the configuration is provided with the number accumulating unit, the result of the filter passing signal number accumulating unit is fed back to the threshold control unit to perform the threshold control, so that the processing load after the azimuth direction filter unit does not become excessive.

In the radar signal processing method according to the third aspect of the present invention, the integration unit that collects the signals that have passed through the azimuth direction filter unit as one target, the position calculation unit that calculates the position from the output signal of the integration unit, and the position calculation unit. The target detection target distance / azimuth spread calculation unit that calculates the spread in the distance direction and azimuth direction of the detection target target at the position calculated by, and the detection target target based on the information of the detection target target distance / direction spread calculation unit A threshold control unit that controls the threshold of the target determination so that only the target is passed, and a target determination unit that determines and outputs the target to be detected using this threshold,
Since the threshold control unit controls so that only the target to be detected passes through, the target can be optimally detected.

A radar signal processing system according to a fourth aspect is the radar signal processing system according to the third aspect, in which the target number accumulating unit for accumulating the number of targets passing through the target determining unit and feeding back the result to the threshold control unit. With this configuration, since the result of the target accumulating unit is fed back to the threshold control unit to perform threshold control, the processing load after the target determining unit does not become excessive.

According to a fifth aspect of the radar signal processing system of the present invention, a quantizer for quantizing the received video, an elevation direction filter unit for performing an elevation direction concatenation test on the signal quantized by the quantizer, and position information Based on the detection target target elevation angle spread calculation unit that calculates the spread in the elevation angle direction based on the size of the detection target target, the elevation direction so that only the detection target target passes using the information of the detection target target elevation angle spread calculation unit A first threshold control unit that controls the threshold of the filter unit, an azimuth direction filter unit that performs azimuth direction continuity verification of the signal that has passed through the elevation angle direction filter unit, and the size of the target to be detected based on the position information. Only the detection target target azimuth spread calculation unit that calculates the azimuth spread and the detection target target azimuth spread calculation unit are used to pass only the detection target target. And a second threshold control section for controlling the threshold of the azimuth direction filter section, and a detection target target elevation angle spread calculation section that receives position information and a detection target target azimuth direction spread that is input. Based on the output of the calculation unit, the elevation angle filter and the azimuth direction filter are controlled by the first and second threshold control units so that only the target to be detected is passed, so that optimum target detection can be performed.

According to a sixth aspect of the radar signal processing method of the present invention, there is provided a tracking target determination section for determining a tracking target of the target based on the target information, and an inter-scan correlation section for obtaining inter-scan correlation based on the result of the tracking target determination section. A tracking calculation unit that performs tracking calculation based on the result of the inter-scan correlation unit, a processing load calculation unit that obtains a processing load of the tracking calculation unit and the inter-scan correlation unit, and the processing load calculation unit based on the result of the processing load calculation unit. Since the threshold control unit that performs the threshold control of the tracking target determination unit is provided, it is possible to obtain the processing load of the inter-scan correlation and the tracking calculation, and only the target with high priority can be tracked when overloaded.

[Brief description of drawings]

FIG. 1 is a first embodiment of a radar signal processing system according to the present invention.
It is a block diagram of.

FIG. 2 is a block diagram of the second embodiment.

FIG. 3 is a block diagram of the third embodiment.

FIG. 4 is a block diagram of a fourth embodiment.

FIG. 5 is a block diagram of a fifth embodiment.

FIG. 6 is a block diagram of a sixth embodiment.

FIG. 7 is a block diagram of a conventional radar signal processing method.

[Explanation of symbols]

 1 Quantization unit 2 Azimuth direction filter unit 3 Integration unit 4 Detection target target direction spread calculation unit 5 Threshold control unit 6 Filter passing signal accumulation unit 7 Target determination unit 8 Position detection unit 9 Detection target target distance / direction spread calculation unit 10 Threshold Control unit 11 Target number accumulation unit 12 Elevation direction filter unit 13 Threshold control unit 14 Detection target target elevation angle spread calculation unit 15 Tracking target determination unit 16 Inter-scan correlation unit 17 Tracking calculation unit 18 Threshold control unit 19 Processing load calculation unit

Claims (6)

[Claims] 1. A quantizer for quantizing a received video, an azimuth direction filter unit for azimuth direction continuous verification of a signal quantized by the quantizer, and a size of a target to be detected based on position information. A target detection target azimuth spread calculation unit for calculating the spread in the azimuth direction, and a threshold for controlling the threshold of the azimuth direction filter unit so that only the detection target target is passed using the information of the detection target target azimuth spread calculation unit. A radar signal processing method comprising: a control unit; and an integration unit that collects signals that have passed through the azimuth direction filter unit as a single target. 2. A filter passing signal number accumulating unit for accumulating the number of signals passing through the azimuth direction filter unit and feeding back the result to the threshold control unit.
The described radar signal processing method. 3. An integration unit that collects signals that have passed through the azimuth direction filter unit as one target, a position calculation unit that calculates a position from an output signal of this integration unit, and a detection target target at the position calculated by this position calculation unit. Based on the information of the detection target distance / azimuth spread calculation unit that calculates the spread in the distance direction and the azimuth direction of the target and the target determination of only the detection target target based on the information of the detection target target distance / direction spread calculation unit. A radar signal processing method comprising: a threshold control unit that controls a threshold; and a target determination unit that uses this threshold to determine and output a target to be detected. 4. The radar signal processing method according to claim 3, further comprising a target number accumulating unit that accumulates the number of targets that have passed through the target determining unit and feeds back the result to the threshold control unit. 5. A quantizer for quantizing a received video, an elevation direction filter unit for performing an elevation direction continuation test on a signal quantized by the quantizer, and a size of a target to be detected based on position information. From the detection target target elevation angle spread calculation unit that calculates the spread in the elevation direction from the above, using the information of the detection target target elevation angle spread calculation unit to control the threshold of the elevation angle direction filter unit so as to pass only the detection target target No. 1 threshold control unit, an azimuth direction filter unit that performs azimuth direction continuity verification of signals that have passed through the elevation angle direction filter unit, and detection that calculates the azimuth direction spread from the size of the detection target based on position information. Using the target target azimuth spread calculation unit and the information of the detection target target azimuth spread calculation unit, the threshold of the azimuth direction filter unit is set so as to pass only the detection target. A second threshold control unit for controlling the threshold, and a radar signal processing method. 6. A tracking target determination unit that determines a tracking target of the target based on target information, an inter-scan correlation unit that obtains an inter-scan correlation based on the result of the tracking target determination unit, and a result of the inter-scan correlation unit. A tracking calculation unit for performing tracking calculation based on the above, a processing load calculation unit for obtaining the processing load of the tracking calculation unit and the inter-scan correlation unit, and threshold control of the tracking target determination unit based on the result of this processing load calculation unit. A radar signal processing method comprising: a threshold control unit for performing.