JPH06347542A - Target tracking device - Google Patents

Abstract

PURPOSE:To accurately perform correlation processing and improve tracking performance by setting a tracking gate in a proper shape indicating a proper range according to the flight performance of a target. CONSTITUTION:Target date input in polar coordinates are converted into the position coordinates (Xi, Yi) of rectangular coordinates. Then, the prediction position (Xpi, Ypi) of a target at a time ti and a target speed (VXsi-1, VYsi-1) at a time Ti-1 are output to a gate setting part. A target gate set at the target prediction position (Xpi, Ypi) at the time ti is set to be a proper shape, for example, heart shape, indicating a proper range according to the maximum acceleration to all directions including the straight line flight of the target at the gate setting part and then a tracking gate signal and the prediction position (Xpi, Ypi) are sent to a gate correlation processing part. The correlation processing of the prediction position (Xpi, Ypi) at the time ti and the position (Xi, Yi) acquired by the radar device is performed within the tracking gate range which is sufficiently large at the correlation processing part, thus achieving an accurate correlation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a target tracking device which sets a tracking gate at a predicted position of a target such as an aircraft and performs a target tracking process.

[0002]

2. Description of the Related Art As is well known, a target tracking device operates at time t.
_It is configured based on a method (referred to as an α-β method) in which the correlation determination between the predicted position at _{n and} the acquired position at time t _n is performed within the range of the tracking gate set at the predicted position (for example, Japanese Patent Application Laid-Open No. 2006-242242). 63-184085).

Here, in the conventional target tracking device, the tracking gate sets the target maximum turning acceleration as a reference, that is, the acceleration in the linear direction is set in a square shape as an equivalent value to the maximum turning acceleration. This is because the setting process is easy.

[0004]

However, when the tracking gate is set on the basis of the maximum turning acceleration of the target, the tracking gate becomes larger than necessary in view of the flight performance of the target. For example, when the aircraft is in a linear acceleration motion, the linear acceleration a is thrust T, mass m, and drag coefficient C.
_D,楊力coefficient C _L, is represented by the equation 1 by using the gravitational acceleration G, the power weights ratio (T / m) usually 1.
It will never exceed 2G. Nevertheless, if the maximum turning acceleration is 3G, the tracking gate also has a linear acceleration of 3G.
Is set as.

[0005]

## EQU1 ## a = (T / m)-(C _D / C _L ) G

Therefore, in the conventional target tracking device, an unnecessarily large tracking gate is set, resulting in erroneous targets such as clutter when the acquired data is weak or the target performs a sudden acceleration motion, for example. Can be correlated with
In other words, there is a problem in that tracking may fail due to a situation in which a correlation occurs at a position that cannot be actually realized from the viewpoint of target flight performance.

The present invention has been made in view of such a problem, and an object thereof is to set a tracking gate in a shape according to the flight performance of a target to enable more accurate correlation and improve the tracking performance. The object of the present invention is to provide a target tracking device that can be operated.

[0008]

In order to achieve the above object, the target tracking device of the present invention has the following structure. That is,
The target tracking device of the present invention is a target tracking device that sets a tracking gate at a predicted position of a target such as an aircraft and performs a target tracking process; the tracking gate has a shape corresponding to a maximum acceleration in all directions of the target. It is set;

[0009]

Next, the operation of the target tracking device of the present invention having the above construction will be described. The tracking gate is basically set to a shape corresponding to the maximum acceleration in all directions including straight flight, although the target altitude, flight vector, atmospheric condition, etc. are also taken into consideration. Therefore, the tracking gate set in the present invention is
It does not become unnecessarily large as in the conventional case, and has an appropriate shape showing an appropriate range according to flight performance, for example, as shown in FIG.

[0010] Smoothing the position at time t _i-1 in FIG. _{1 (X Si-1, Y} Si-1) and velocity _{(V XSi-1, V YSi} -1) to the basis determined prediction at time t _i was At the position (X _Pi , Y _Pi ), conventionally, a square tracking gate (a) is set based on the maximum turning acceleration of the target, but it is set according to the maximum acceleration of the target in all directions. The tracking gate of the present invention shows a narrow region within the range of the conventional tracking gate (a) as shown in (b).

Thus, according to the present invention, since the tracking gate is set to have an appropriate shape showing an appropriate range according to the flight performance of the target, more accurate correlation can be performed,
Tracking performance can be improved.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 shows a target tracking device according to an embodiment of the present invention. This target tracking device is similar to the conventional device in terms of components, and therefore the basic operation of each element is similar to the conventional device, but the function of the gate setting unit 4 and the gate setting unit 4 are the same.
The function of the elements (2, 3, 6, 7, 8) related to is added with some minor changes.

In FIG. 2, the radar apparatus 1 has a position (R) acquired at the i-th rotation of the antenna (that is, time t _i ).
The data of _i , θ _i ) is given to one input of the target detecting section 3, but the gate setting section 4 gives the gate signal G _i at the time t _{i to} the other input of the target detecting section 3.

The target detection unit 3 detects a target from the position data output by the radar device 1 based on the gate signal G _i from the gate setting unit 4, and detects the position (R _i , θ) of the target.
The data _i ) is output to the target buffer unit 5.

The target buffer unit 5 converts the target position data (R _i , θ _i ) input in polar coordinates into Cartesian coordinate position data (X _i , Y _i ), and the gate correlation processing unit 6 converts it.
Output to.

[0016] In the track buffer 2, the predicted position data (X _Pi, Y _Pi) of the target at time t _i and the time t target velocity data at _{i-1 (V XSi-1} , V YSi-1) and while outputting the gate setting unit 4, a time t _i-1 target velocity data at _{(V XSi-1, V YSi} -1) and the position data (X _Si-1,
Y _Si-1 ) and Y _Si-1 ) are applied to one input of the smoothing processing unit 7.

In the gate setting unit 4, the tracking gate to be set at the predicted position (X _Pi , Y _Pi ) of the target at time t _i is set to have a shape corresponding to the maximum acceleration in all directions of the target given from the outside. Then, the gate signal G _i is _supplied to the target detection unit 3, and the gate signal G _i and the predicted position data (X _Pi , Y _Pi ) are output to the gate correlation processing unit 6.

Here, since the tracking gate is set according to the maximum acceleration in all directions including the target straight flight, its shape does not become unnecessarily large as in the conventional case. For example, FIG. As indicated by (b) in (b), the shape becomes an appropriate so-called heart shape showing an appropriate range according to flight performance.

Since the target acceleration also depends on the target speed at that time, speed data is obtained from the track buffer unit 2 to ensure the tracking gate setting.

In setting the tracking gate, altitude, flight vector, atmospheric condition, etc. may be taken into consideration.

Next, in the gate correlation processing section 6, time t _i
The correlation processing between the predicted position (X _Pi , Y _Pi ) and the position (X _i , Y _i ) acquired by the radar device 1 in the tracking gate G _i
Within the range of (3) and outputs the correlated predicted position data (X _Pi , Y _Pi ) and acquired position data (X _i , Y _i ) to the smoothing processing unit 7.

The smoothing processing unit 7 performs smoothing processing on the output data of the track buffer unit 2 and the output data of the gate correlation processing unit 6 to obtain smoothed position data (X _Si ,
Y _Si ) and the smoothed velocity data (V _XSi , V _YSi ) are obtained and output to the track prediction unit 8.

The track prediction section 8 executes track prediction processing on the output data of the smoothing processing section 7 to obtain track predicted position data (X _{Pi + 1} , Y _{Pi + 1} ) and smooths this track predicted position data. The _converted position data (X _Si , Y _Si ) and the smoothed velocity data (V _XSi , V _YSi ) are output to the track buffer unit 2.

The above operation is repeatedly performed on the position data acquired for each rotation of the antenna of the radar apparatus 1 to track the target.

The timing control section 9 outputs a processing timing signal to each element described above based on the azimuth signal from the radar device 1.

[0026]

As described above, in the target tracking device of the present invention, the tracking gate has a shape corresponding to the maximum acceleration of the target in all directions, that is, an appropriate shape indicating a proper range according to the flight performance. Since it can be set to, it does not become unnecessarily large as in the conventional case, more accurate correlation can be obtained, and there is an effect that the tracking performance can be improved.

[Brief description of drawings]

FIG. 1 is a comparative explanatory diagram of a tracking gate set and used in a tracking processing apparatus of the present invention and a tracking gate set and used in a conventional apparatus.

FIG. 2 is a configuration block diagram of a tracking processing device according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Radar device 2 Track buffer section 3 Target detection section 4 Gate setting section 5 Target buffer section 6 Gate correlation processing section 7 Smoothing processing section 8 Track tracking section 9 Timing control section (a) Conventional tracking gate (b) of the present invention Tracking gate

Claims (2)

[Claims] 1. A target tracking device that sets a tracking gate at a predicted position of a target of an aircraft or the like and performs a target tracking process;
The target tracking device is configured to have a shape corresponding to a maximum acceleration of a target in all directions. 2. The target tracking device according to claim 1, wherein in setting the tracking gate, data such as a target altitude, a flight vector, and a weather condition are also taken into consideration.