JP2009069020A - Radar equipment - Google Patents

Abstract

A radar apparatus capable of easily and reliably detecting and tracking a target aircraft without being affected by weather such as strong winds.
A target obtained by a high / low aerial device 11 and an azimuth antenna device 12 by a target information detector 21 utilizing the fact that the distance to a target such as an aircraft and the Doppler frequency components coincide in the height direction and the azimuth direction. It is determined whether or not the distance and Doppler frequency components match, and if they match, it is determined as a target, and a message indicating this target and numerical information of “distance”, “altitude” and “azimuth” are displayed. 16 is displayed in the height direction display area and the azimuth direction display area.
[Selection] Figure 3

Description

  The present invention relates to a radar apparatus for monitoring the flight state of an aircraft, for example.

  Conventionally, ASR (Airport Surveillance Radar) or the like has been used as a radar device for air traffic control (for example, Non-Patent Document 1).

This type of radar apparatus detects and tracks the flight position of an aircraft by transmitting radar waves to the aircraft in flight and receiving and detecting radar reflected waves from the aircraft.
Radar technology The Institute of Electronics, Information and Communication Engineers.

  By the way, in the above-mentioned radar device, a cloud that flows quickly may be erroneously detected as a target due to weather or the like, and in this case, it is difficult to specify the target.

  Accordingly, an object of the present invention is to provide a radar apparatus capable of easily and reliably detecting and tracking a target aircraft without being affected by weather such as strong winds.

  In order to achieve the above object, a radar apparatus according to the present invention includes a first antenna that radiates a radar wave, scans a space in which a target aircraft exists in a height direction, and receives a reflected wave of the radar wave. A device, a second antenna device that radiates a radar wave, scans the space in a direction perpendicular to the elevation direction, and receives a reflected wave of the radar wave, and a Doppler frequency component from the output of the first antenna device And first detection means for detecting the distance to the target, second detection means for detecting the Doppler frequency component and the distance to the target from the output of the second antenna device, and the first and second detection means. From these outputs, it is determined whether or not the Doppler frequency component and the distance coincide with each other, and a target specifying means for specifying the target from the determination result is provided.

  According to this configuration, the distance to the aircraft and the Doppler frequency component in the elevation direction and the azimuth direction match, and the distance and the Doppler frequency component in the elevation direction and the azimuth direction match before the target detection processing. Whether or not to do so is determined, and this makes it possible to reliably determine the target regardless of the influence of the weather or the like.

  Further, the apparatus further comprises fixed clutter removing means for removing fixed clutter existing in the scanning area from the outputs of the first and second detecting means and supplying the same to the target specifying means.

  According to this configuration, the fixed clutter is removed from the output of each of the first and second antenna apparatuses prior to the target determination process using the map data on which the position information of the fixed clutter is placed. Therefore, the target can be determined efficiently.

  Further, the display device includes a display and display control means for displaying the target distance, height, and direction specified by the target specifying means on the display using numerals.

  According to this configuration, the target can be confirmed on an easy-to-see display screen.

  As described above in detail, according to the present invention, it is possible to provide a radar device that can easily and reliably detect and track a target aircraft without being affected by weather such as strong winds.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
First, prior to describing an embodiment according to the present invention, an operation principle thereof will be described.

  1 and 2 show a target detection operation in the radar apparatus. As shown in FIG. 1, the high and low aerial device 11 of the radar device transmits a radar wave and performs beam scanning in a vertical direction (high and low direction) in a space where a target TA such as an aircraft is estimated to exist. Then, the target TA is detected by receiving and detecting the radar reflected wave from the target TA.

  On the other hand, as shown in FIG. 2, the azimuth antenna device 12 of the radar device transmits a radar wave and performs beam scanning in the left-right direction (azimuth direction) in a space where a target TA such as an aircraft is estimated to exist. Then, the target TA is detected by receiving and detecting the radar reflected wave from the target TA.

  By the way, the high and low aerial device 11 and the azimuth antenna device 12 also detect weather clutter WK such as clouds and ground clutter GK such as mountains and buildings in the scanning area. Here, when the weather is bad or the wind is strong, the weather clutter WK flows quickly, and the weather clutter WK may be detected and tracked as the target TA. Since the weather clutter WK often flows horizontally, when a radar wave is transmitted from a direction perpendicular to the horizontal direction, that is, a height direction, doppler does not occur.

  On the other hand, since the aircraft flies diagonally, a Doppler frequency corresponding to the difference between the moving direction of the aircraft and the radar wave transmission direction is generated. Further, since the target TA of an aircraft or the like is smaller than that of the weather clutter WK, it can be considered that the target TA is located at the same distance when viewed from the high and low antenna apparatus 11 and the azimuth antenna apparatus 12.

  Therefore, the present invention specifies the target TA when the distance to the target TA from each of the high and low antenna devices 11 and the azimuth antenna device 12 matches the Doppler frequency component.

  Based on the above principle, embodiments of the present invention will be described below.

  FIG. 3 is a block diagram showing the configuration of the radar apparatus according to the present invention. In FIG. 3, the radar wave transmitted from the high / low antenna apparatus 11 is transmitted in a predetermined direction. The reflected wave is received and detected by the high / low antenna apparatus 11. Although the details are not shown in the drawings, the elevation antenna apparatus 11 is capable of angle control within a certain range, and by this angle control, the radar wave can be scanned in the vertical direction (altitude direction).

  The radar wave transmitted from the azimuth antenna device 12 is transmitted in a predetermined direction. The reflected wave is received and detected by the azimuth antenna apparatus 12. Although not shown in detail, the azimuth antenna device 12 is capable of angle control within a certain range, and by this angle control, the radar wave can be scanned in the horizontal direction (azimuth direction).

  The radar wave output from the high / low antenna apparatus 11 is modulated. Also, the received signal obtained by the high / low antenna apparatus 11 is time-division processed by the time-division processing unit 13 and then supplied to the reception signal processing system 14 to generate a sum signal Σ and a difference signal Δ. The same applies to the azimuth antenna apparatus 12. The received signal processing system 14 is provided with a Doppler component extractor 141.

  The Doppler component extractor 141 detects the Doppler frequency from the frequency error included in the modulation component of the input signal. The output of the Doppler component extractor 141 is subjected to predetermined time division processing by the time division processing unit 15 and displayed on the display 16. On the display 16, the information obtained by the high / low antenna apparatus 11 and the information obtained by the azimuth antenna apparatus 12 are separately displayed on the same display screen.

  The output of the Doppler component extractor 141 is supplied to the clutter removal units 17 and 18, respectively. The clutter removal unit 17 stores and holds map data in which the position of the ground clutter GK is described in the height direction, and removes information on the ground clutter GK from the output of the Doppler component extractor 141 based on this map data. Then, it is supplied to the elevation direction reception processing unit 19.

  Further, the clutter removal unit 18 stores and holds map data in which the position of the ground clutter GK is described with respect to the azimuth direction, and information on the ground clutter GK from the output of the Doppler component extractor 141 based on this map data. Is supplied to the azimuth direction reception processing unit 20.

  The elevation direction reception processing unit 19 extracts the Doppler frequency component from the output of the clutter removal unit 17, detects the target direction in the elevation direction from the sum signal Σ and the difference signal Δ, performs correlation processing on the sum signal Σ, The distance to the target TA is detected from the correlation result.

  The azimuth direction reception processing unit 20 extracts a Doppler frequency component from the output of the clutter removal unit 18, detects a target direction related to the azimuth direction from the sum signal Σ and the difference signal Δ, and performs correlation processing on the sum signal Σ. The distance to the target TA is detected from the correlation result.

  The outputs of the elevation direction reception processing unit 19 and the azimuth direction reception processing unit 20 are supplied to the target information detector 21. The target information detector 21 determines whether or not the Doppler frequency component and the distance match among the outputs of the elevation direction reception processing unit 19 and the azimuth direction reception processing unit 20. Is displayed on the display 16 together with numerical information of “distance”, “altitude”, and “azimuth”.

  Next, in the above-described configuration, the characteristic processing operation will be described below.

  The high and low aerial device 11 and the azimuth antenna device 12 obtain a modulated output of a transmission radar wave. The Doppler frequency can be detected from the phase difference between the transmission modulation wavelength and the reflected reception wavelength. Further, the distance to the target TA can be calculated from the phase difference between the modulated signal of the transmitted wave and the reflected wave.

  After detecting the target, the high and low aerial device 11 and the azimuth antenna device 12 are directed in the target direction and track the target TA.

  Reflected radar waves from the target TA are received at a plurality of locations of the high / low antenna apparatus 11 and the azimuth antenna apparatus 12. The reception signal at each location is generated as a sum signal Σ and a difference signal Δ by the reception signal processing system 14. The sum signal Σ and the difference signal Δ are extracted from the Doppler frequency component by the Doppler component extractor 141, and the information on the ground clutter GK is removed by the clutter removal units 17 and 18, and then the high and low direction reception processing unit 19 and the azimuth direction The distance to the target TA, the azimuth direction, and the elevation direction are calculated by the reception processing unit 20 and supplied to the target information detector 21.

  The target information detector 21 includes “distance” and “Doppler frequency component” in the output of the elevation direction reception processing unit 19, and “distance” and “Doppler frequency component” in the output of the azimuth direction reception processing unit 20. Are compared to determine whether they match. If they do not match, it is determined as weather clutter WK and the process ends. If they match, the message indicating the target TA and numerical information of “distance”, “altitude” and “azimuth” are displayed on the display 16. It is supplied and displayed in the elevation display area and the azimuth direction display area. Therefore, the operator can confirm the position of the target TA by this display.

  As described above, in the above-described embodiment, the target information detector 21 uses the high and low antenna apparatus 11 and the azimuth antenna by utilizing the fact that the distance to the target TA and the Doppler frequency components coincide with each other in the height direction and the azimuth direction. It is determined whether or not the distance to the target TA and the Doppler frequency component obtained by the device 12 match each other. If they match, the target TA is determined, and the message indicating the target TA and the “distance”, “altitude”, and The numerical information of “azimuth” is supplied to the display 16 so as to be displayed in the elevation display area and the orientation display area.

  Accordingly, it is possible to reliably determine the target regardless of the influence of the weather or the like.

  In the above-described embodiment, the clutter removing units 17 and 18 use the map data on which the position information of the ground clutter GK is placed, prior to the target determination process by the target information detector 21, Since the ground clutter GK is removed from the output of each azimuth antenna device 12, the target TA can be determined efficiently.

  Although the present invention has been described based on the embodiments, the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment.

The figure which shows the example of the target detection operation | movement to the elevation direction in the radar apparatus relevant to this invention. The figure which shows the example of the detection operation | movement of the target to the azimuth | direction direction in the radar apparatus related to this invention. 1 is a block diagram showing an embodiment of a radar apparatus according to the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... High and low antenna apparatus, 12 ... Direction antenna apparatus, 13, 15 ... Time division processing part, 14 ... Reception signal processing system, 16 ... Display, 17, 18 ... Clutter removal part, 19 ... High / low direction reception processing part, 20 ... Azimuth direction reception processing unit, 21 ... Target information detector.

Claims (3)

A first aerial device that radiates a radar wave and scans a space where a target aircraft exists in a vertical direction and receives a reflected wave of the radar wave;
A second antenna device that radiates the radar wave, scans the space in a direction perpendicular to the elevation direction, and receives a reflected wave of the radar wave;
First detection means for detecting a Doppler frequency component and a distance to the target from an output of the first antenna device;
Second detection means for detecting a Doppler frequency component and a distance to the target from an output of the second antenna device;
It comprises whether or not the Doppler frequency component and the distance coincide with each other from the outputs of the first and second detection means, and comprises a target specifying means for specifying the target from the determination result. Radar device. 2. The apparatus according to claim 1, further comprising fixed clutter removal means for removing fixed clutter existing in a scanning area from each output of the first and second detection means and supplying the same to the target specifying means. The radar apparatus described. And an indicator
The radar apparatus according to claim 1, further comprising display control means for displaying the target distance, height, and direction specified by the target specifying means on the display unit with numerals.

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