JPH03282389A - Accurate measurement entry radar - Google Patents

Abstract

PURPOSE:To prevent a weather clutter, etc., other than an aircraft from being tracked by correlating the converted position coordinates of an airport control radar and a secondary control radar with a new target of the accurate measuring entry radar in three or two dimensions. CONSTITUTION:A target detection part 4 is informed of a beam direction at the time of reception with data from a beam direction control part 8 to detect the distance, azimuth, and elevation of a target and send them to a PAR and ASR/SIF correlation processing part 10 as search target data r', theta'AZ, and theta'EL. On the other hand, ASR/SIF data from the airport control radar and secondary control radar are inputted to a coordinate conversion part 9 and converted from position data R, theta, and H to data (r), thetaAZ, and thetaEL of the coordinate system of the accurate measurement entry radar (PAR); and tracking start target data is selected by three-dimensional position correlation 10a when there is high-level data H or two-dimensional position correlation 10b when not and a tracking start position is determined. Consequently, the weather clutter, etc., is prevented from being tracked and even a target corresponding to ASR/SIF data including no high-level data can begin to be tracked by the PAR.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a precision approach radar for landing guidance used in air traffic control, and more particularly to a precision approach radar that tracks an aircraft using an electronically scanned antenna.

[Conventional technology]

Precision Approach Radar (hereinafter referred to as PAR: Precisio
nApproach Radar) is the azimuth angle of an aircraft approaching the runway on the final approach course for landing.

This is a landing guidance radar that measures the elevation angle and distance and safely guides the aircraft toward the touchdown point on the runway. Normally, until the final approach course meeting using PAR, airport surveillance radar (hereinafter referred to as ASR)
Rport 5veilance Radar), and Secondary Surveillance Radar (hereinafter referred to as SSR: 5econ)
It is guided by a dary 5urveilance Radar), and is approximately 1 ONM (N
At nautical mile (nautical mile), control is handed over to PAR.

Conventionally, this type of precision approach radar has two beam scanning patterns, as shown in Figure 3: a search scanning pattern that evenly scans the entire PAR coverage area, and a tracking scanning pattern that directs the beam to each aircraft individually. Then, the beam is directed in the direction of the position of the received data in a search scanning pattern and tracking begins.

The example in Figure 3 shows a case where the number of tracking aircraft is three, and the pencil beam is scanned from the top left of the search surface downwards in search mode, and then the beam direction is shifted to the right for the second, third, and so on. Scan to the right edge while shifting. During this search period, in this example, three tracking aircraft AI, A2. Aim the beam at A3 and perform short-cycle update tracking. The condition for the tracking device to start tracking is when there is new data that has no positional correlation with the data that has already been tracked among the data captured during search scanning.

FIG. 5 is a block diagram of a first example of a conventional precision approach radar. In this radar, first, the beam direction control section 8 sequentially sends a phase shift control signal to the electronic scanning antenna 1 for search scanning, and controls the direction of the beam pattern by the radiated radio waves.

At the same time, the transmitter 2 sends a transmission high-frequency signal to the electronic scanning antenna 1 to form a beam pattern using radiated radio waves. When the emitted radio waves hit the target, the reflected waves are received by the receiver 3 via the electronic scanning antenna 1,
The received video is input to the target detection unit 4.

Based on the beam direction data from the beam direction control section 8,
The beam direction at the time of reception is notified to the target detection section 4, and the target distance, azimuth, and elevation angle are detected by the target detection section 4 and sent to the tracking processing section 5 as search target data. The tracking processing unit 5 compares the data with the tracking target in the track file 6, and if the data is new, it is registered in the track file 6 as a new tracking target. The track file 6 is a file that records position information for each tracking device.

If a target correlated with the target is obtained again in the next search cycle, the tracking start position is predicted and registered in the trunk file 6, and the beam direction control unit 8
Send beam direction data to.

The beam direction control section 8 sequentially sends phase shift control signals for tracking to the electronic scanning antenna 1 based on the beam direction data from the tracking processing section 5 between search scans to control the beam radiation direction.

When tracking is started in this manner, the tracking processing unit 5 repeats tracking updates at the tracking cycle as shown in FIG. 4 based on the tracking target data. The tracking processing unit 5 sends control display data to the display unit 7, where the target position is displayed.

Further, FIG. 6 is a block diagram of a second example of a conventional precision approach radar. This second example performs the same operations in the same parts as the first example, but here ASR/SS is performed without search scanning.
Based on the R data, the coordinate conversion unit 9 converts A S R/S
When the position information is converted from the S R coordinates to the PARO coordinates and the tracking processing unit 5 finds a new target that is not in the track file 6, it is newly registered in the track file 6 as a new tracking target and the beam is set based on the position. The beam direction data is sent to the direction control unit 8 to start tracking.

[Problem to be solved by the invention]

In the first example of the conventional precision approach radar described above, tracking is started based on the data obtained during search scanning, except for those that are already trackers, so due to the nature of the -order radar, There is a problem in that there is a very high possibility that weather clutter and the like other than aircraft will be tracked. Tracking weather clutter and the like is a wasteful process, and displaying it as an aircraft poses a major hindrance to air traffic control. Furthermore, when the weather is bad, a lot of weather clutter is likely to be tracked, and if the maximum number of aircraft that can be tracked by the tracking processing section has been reached, there will be a problem that the actual aircraft will not be tracked.

On the other hand, in the second example, it is possible to improve the problem of the first example described above, but if altitude information cannot be obtained from the mode C response of the SSR, for example, an aircraft without a transponder or a transponder malfunctions. Since only distance and direction position data can be obtained from the position information of aircraft, etc. that have been lost, they are not subject to processing, and there is a problem in that tracking of those aircraft cannot be started using PAR.

An object of the present invention is to provide a precision approach radar that makes it possible to solve these conventional problems all at once.

[Means to solve the problem]

The precision approach radar of the present invention is an electronic scanning antenna.

Accurately measure the position data of the airport surveillance radar and the secondary surveillance radar on a radar equipped with a transmitting section, a receiving section, a target detection section, a tracking processing section, a recording means 2 display section for track files, a display section, and a beam direction control section. a coordinate conversion unit that converts into
Correlation processing means is provided for correlating the coordinate-converted position data with a new target in the search target data of the precision approach radar in three or two dimensions and outputting the position data to the tracking processing section.

In this case, the correlation processing means includes a three-dimensional correlation processing section that operates when altitude information is present in the coordinate-transformed position data, and a two-dimensional correlation processing section that operates when altitude information does not exist. ing.

[Effect]

According to the present invention, data identified as an aircraft by an airport surveillance radar and a secondary surveillance radar is coordinate-transformed, and a three-dimensional or two-dimensional positional correlation is established between the data and the target data in the same coordinate system to obtain a target to start tracking. By selecting the tracking start position and determining the tracking start position, tracking of weather clutter, etc. other than the aircraft is prevented. Additionally, tracking can be started for targets corresponding to data from airport surveillance radars and secondary surveillance radars that do not have altitude information.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention, in which the same parts as in the conventional example are given the same reference numerals. That is, the direction of the beam emitted into space in the electronic scanning antenna 1 can be controlled by a phase shift control signal. Further, the transmitter 2 outputs a radar transmission high frequency signal. Further, the receiving section 3 receives radio waves that are reflected by the signal from the transmitting section 2 upon hitting the target. The target detection unit 4 detects the distance, azimuth, and elevation angle of the target based on the video received from the reception unit 3 and outputs it as target data. The tracking processing unit 5 updates the tracking position of the tracking target data, and the track file 6 records position information for each of the tracking targets. The display unit 7 displays the position of the target based on the display data of the target. Beam direction control section 8
sends a tracking phase shift control signal to the electronic scanning antenna 1 based on a phase shift control signal for successively emitting search scanning beams and beam direction data.

Further, the coordinate conversion unit 9 converts the position data of ASR/SIF data into PAR coordinates. In this embodiment, the target position information of the ASR/S IF data converted into PAR coordinates is correlated with the new target of the PAR search target data in three or two dimensions, and if there is a correlation, a new target is PAR that notifies the tracking processing unit of the position as the tracking start target;
An ASR/SIF correlation processing section 10 is provided. This P
A.R.

The ASR/SIF correlation processing section 10 includes a three-dimensional correlation processing section 10a and a two-dimensional correlation processing section 10b.

According to the precision approach radar with this configuration, first, the beam direction control unit 8 sequentially sends a phase shift control signal to the electronic scanning antenna 1 for search scanning, and controls the direction of the beam pattern by the radiated radio waves. At the same time, the transmitter 2 sends a transmission high-frequency signal to the electronic scanning antenna 1 to form a beam pattern using radiated radio waves. When the emitted radio waves hit the target, the reflected waves are received by the receiver 3 via the electronic scanning antenna 1, and the received video is input to the target detector 4. The beam direction data from the beam direction control unit 8 informs the target detection unit 4 of the beam direction at the time of reception, and the target distance, azimuth, and elevation angle are detected by the target detection unit 4, and the search target data is transmitted between PAR and ASR/SIF. It is sent to the correlation processing section 10.

On the other hand, the ASR/SIF data is input to the coordinate conversion section 9, and the ASR/SIF coordinate position data (R.

θ, H) to (r, θAZ+θ
2L).

Usually, this ASR/SIF data is data that has already been identified as an aircraft. FIG. 2 is a diagram illustrating this coordinate transformation in detail. Let R be the distance according to ASR/SIF coordinates, θ be the direction from north, and H be the height. The distance according to PAR coordinates is r, the azimuth θ□, and the elevation angle is θ□
, and so on. Now, consider orthogonal coordinates of the x, y, and z axes, with the PAR θ=00 direction as the Y axis and the PAR installation position as the origin O. Here, when the angle in the Y-axis direction from the north is Δθ9, and the ASR/SIF installation position is expressed on the PAR orthogonal coordinate system, the installation position condition is (-x, -y, O). Assume. ASR/SIF data target value 1! If (R, θ, H) is converted to the PAR orthogonal coordinate system and (a, b, c) is obtained, then a==(R” −H / t s t n (θ
−ΔθN)−ΔXb= (R” −H”)”” co
s (θbhf)H) −Δyc=H Here, it is assumed that R, H, ΔX, and Δy have uniform units.

That's what happens.

From this PAR orthogonal coordinate system to the PAR polar coordinate system (“θ1□,
θ! When converted to
n-'(a/b)θtt=jan-'C
c/(a"+bQ"") is obtained.

Above, we have described the processing when there is altitude information as input to the coordinate conversion section 9, but if there is no altitude information, the PA
If the maximum altitude limited by the coverage area of R is H□8, the same calculation as above is performed using that value as altitude information. Let the final result be (rl, θ, 21). Also, the final calculated value at altitude 0 is (rzθA2□).

In this way, the results of the coordinate conversion unit 9 are divided into two types: when there is altitude information and when there is no altitude information, and PAR, ASR
/SIF correlation processing unit 10 also performs 3
The processing is divided into processing in the dimensional correlation processing unit 10a and processing in the two-dimensional correlation processing unit tab.

In the three-dimensional correlation processing section 10a, (r
, θA21 θEL) based on (r±Δr, θA2
A three-dimensional gate of ±ΔθAZ+θ, ±ΔθEL) is created. Here, Δr, ΔθA2+ Δθ, are distances.

Represents half the gate size for azimuth and elevation. If the position (r', θ'1□, θEL) of the search target data from the target detection unit 4 is included in this three-dimensional gate, it is determined that there is a correlation, and the position (r' , θ′
, 2. θ EL) is passed to the tracking processing unit 5. Similarly, in the two-dimensional correlation processing unit 10b, (rl, θ
1□, ), (r=.

Based on θ1□, ), (rz−Δr, θ1□2−ΔθAZ
) to (r1+Δr, θAll+Δθoz) are created. This means that r, > rz , θ, 2I
〉This is an example in the case of θA2□. If (r', θ'1□) excluding θ'EL of the search target data from the target detection unit 4 is included in this two-dimensional gate, it is determined that there is a correlation, and from θ4□2-ΔθA2 The correlation is determined for each search target data that may include the range of θ1□1+Δθ1□, and if the correlation is found for multiple aircraft, the tracking start target data is not output and the correlation for only one aircraft is determined. When the tracking start target data (r', θ'A2.
θ EL) is passed to the tracking processing unit 5. Of the search target data, only new data that is not registered as a tracking target in the track file 6 is correlated.

The tracking processing unit 5 newly registers a tracking start target in the track file 6 and starts tracking. The tracking processing section 5 passes the beam direction data to the beam direction control section 8, and the beam direction control section 8 sends a phase shift control signal to the electronic scanning antenna 1 to control the direction of the beam pattern of the radiated radio waves. At the same time, the transmitter 2 sends a transmission high-frequency signal to the electronic scanning antenna 1 to form a beam pattern using radiated radio waves.

The emitted radio waves capture the tracked target, the reflected waves thereof are received by the receiver 3 via the electronic scanning antenna, and the received video is input to the target detector 4.

Based on the beam direction data from the beam direction control section 8,
The beam direction at the time of reception is notified to the target detection section 4, and the target distance, azimuth, and elevation angle are detected by the target detection section 4 and sent to the tracking processing section 5 as tracking target data.

When tracking is started in this way, the tracking processing unit 5 repeats tracking updates at the tracking cycle as shown in FIG. 4 based on the tracking target data. The tracking processing unit 5 sends control display data to the display unit 7, where the target position is displayed.

〔Effect of the invention〕

As explained above, the present invention is directed to an aircraft that has been identified as an aircraft.
SR/SIF data and PAR search target data are usually correlated three-dimensionally in the same coordinate system,
When there is no altitude information, the tracking start target is selected by taking two-dimensional positional correlation and the tracking start position is determined.This has the effect of not tracking weather clutter other than aircraft, and when there is no altitude information. There is an effect that tracking can be started using PAR even for targets corresponding to ASR/SrF data.

[Brief explanation of drawings]

Figure 1 is a block diagram of an embodiment of the present invention, Figure 2 is an AS
A diagram showing the relationship between R/SIF coordinates and PAR coordinates, Figure 3 is a conceptual diagram showing beam scanning of precision approach radar using an electronic scanning antenna, Figure 4 is a diagram showing the time series of beam scanning, FIG. 5 is a block diagram of a first example of a conventional precision approach radar, and FIG. 6 is a block diagram of a second example of a conventional precision approach radar. DESCRIPTION OF SYMBOLS 1... Electronic scanning antenna, 2... Transmission section, 3... Receiving section, 4... Target detection section, 5... Tracking processing section, 6.
...Track file, 7.Display section, 8.Beam direction control section, 9.Coordinate conversion section, 10.PAR,A
SR/S IF correlation processing section, 10a... three-dimensional correlation processing section, lOb... two-dimensional correlation processing section. Figure 3 Figure 4

Claims (1)

[Claims] 1. An electronic scanning antenna whose radiation beam direction is controlled by a phase shift control signal, a transmitting section that outputs radio waves, a receiving section that receives reflected radio waves, and a target target based on the received signal. a target detection unit that detects the distance, azimuth, and elevation angle of the target data and outputs it as target data; a tracking processing unit that updates the tracking position of the target data; a recording unit that records the tracking position of the target data; a display section that displays a target position based on the above; a beam direction control section that sends the phase shift control signal to the electronic scanning antenna; and a beam direction control section that converts the position data of the airport surveillance radar and the secondary surveillance radar into precision approach radar coordinates. a coordinate conversion unit that performs the coordinate conversion, and a correlation processing unit that correlates the coordinate-converted position data with a new target of the search target data of the precision approach radar in three or two dimensions and outputs the position data to the tracking processing unit. A precise measurement approach radar characterized by comprising: 2. The correlation processing means includes a three-dimensional correlation processing unit that is operated when altitude information is present in the coordinate-converted position data;
The precision approach radar according to claim 1, further comprising a two-dimensional correlation processing section that is operated when altitude information does not exist. 3. The precision approach radar according to claim 1 or 2, wherein the recording means is constituted by a track file for recording position information of the aircraft to be tracked.