JP2715596B2 - Radar target information processing device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to radar target information processing, and more particularly to a technique for converting target track data obtained from each radar device into plot data.

(Prior Art) A radar device capable of detecting and tracking a target such as an aircraft usually displays the tracked target data on a display device, and visually monitors the target to monitor the aircraft in units of the radar device. ing. However, when monitoring a wide area, a plurality of radars are connected to form a network, target data from each radar is collected in a target information processing device, and processing such as integration and tracking of targets is performed for monitoring. Is done. The target information processing system includes a centralized system for collecting, integrating, and tracking target data (hereinafter, referred to as plot data) obtained by simply performing target detection processing without performing tracking processing from each radar. In addition, there is a distributed method in which target data (hereinafter, referred to as track data) obtained by each radar up to target detection processing and tracking processing is collected from each radar and integrated processing is performed.

When the centralized target information processing device collects plot data from each radar and integrates the target,
Since the antennas of each radar perform asynchronous rotation or asynchronous beam scanning with each other, in addition to the target position information, each radar notifies the time at which each antenna headed north, and based on those times, plot data of each radar based on those times Need to be integrated after performing position correction based on the same time reference.

The radar connected to such a centralized target information processing device may be a radar that normally outputs only plot data, and does not require a tracking processing function. However, in the case of connecting a radar having a tracking processing function as described above and a complex type radar in which a long-distance region and a short-distance region are asynchronously scanned with antenna beams having different transmission powers from each other, the radar is used. Is only track data subjected to tracking processing. In order to connect such a radar to the target information processing apparatus described above, a pseudo antenna rotation is assumed to control the output timing of the plot data, and the target data in a direction matching the antenna direction is tracked. It is necessary to perform conversion so that the data can be calculated from the data and output in a pseudo manner as plot data.

Figure 2 is a function of generating by converting the pseudo plot data from the track data a diagram schematically showing, T ₁ is a track data when the t = t ₀ a pseudo rotation of the antenna is oriented azimuth 0 ° It indicates the position, P ₁ is Δt time elapsed time indicates Δt min corrected position of the track data T ₁ consistent with the orientation of the antenna the position data is output becomes plot data.

In order to generate the pseudo plot data in this manner, the time when the aerial direction of the pseudo rotation coincides with the direction corresponding to the temporal transition of the track data (t in FIG. 2).
= T ₀ + Δt), and the position at the time when the azimuth coincides must be calculated from the position data and the speed data in the track data.

When the relationship between the track data T ₁ and plot data P ₁ described above have the relationship shown in FIG. 3, the following expression is established.

Where ω: angular velocity of the antenna, (X ₀ , Y ₀ ): track data T ₁ when the antenna has an azimuth of 0 °
Position data (coordinates), (,): the speed data of the track data _{T 1, (X 1, Y} 1): location data (plot data P ₁₎ of track data T ₁ of the when the orientation is matched, plot data The position data (X ₁ ,
To determine Y ₁ ), it is necessary to first calculate Δt from equation (1).

(Problem to be Solved by the Invention) However, Δt cannot be analytically obtained from the equation (1).

Therefore, instead, the time Δt ′ when the antenna passes the position of the track data T ₁ is obtained from the equation (2),
Using t ', the position is corrected from equations (3) and (4),
The method of generating plot data was adopted.

However, this method enough to track data T ₁ is located if the position away from the azimuth on 0 °, (1) and (2)
There is a problem that the error of the azimuth coincidence time due to the difference from the equation becomes large, and the position error of the plot data is taken, which undesirably influences the integration of the target and the tracking processing.

SUMMARY OF THE INVENTION In view of the above-described problems of the following technology, it is an object of the present invention to reduce the azimuth difference to an allowable value or less by repeating the correction while finely adjusting the correction value recursively and stepwise to reduce the position error of the plot data. It is an object of the present invention to provide a radar target information processing apparatus capable of reducing the size of the radar target.

(Means for Solving the Problems) The present invention has the following means configuration to achieve the above object.

That is, the radar target information processing apparatus of the present invention comprises: track data correction means for correcting the input radar target track data based on its position information, speed information, and correction time information; Target azimuth calculating means for calculating the azimuth of the antenna; pseudo antenna azimuth azimuth calculating means for calculating the antenna azimuth from the rotational speed and the correction time information assuming a pseudo antenna; difference between the calculated target azimuth and the antenna azimuth To generate a control signal for determining the amount of time correction from the magnitude of the azimuth difference, and to generate plot data from the track data after the position correction when the azimuth difference becomes an appropriate value. An azimuth difference determining means for outputting an instruction control signal; and a compensation determined by the control signal from the azimuth difference determining means to the track data correcting means. Time generating means for generating and transmitting time; and plot data generating means for outputting plot data in response to an instruction control signal from the azimuth difference determining means using the track data after position correction from the track data correcting means. It is characterized by the following.

(Embodiment) Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a system diagram showing the configuration of one embodiment of the present invention. The track data correction circuit 1 corrects the position of the track data based on the input track data (X ₀ , Y ₀ ,) and the time Δt _n generated by the time generation circuit 3 according to the following formula, and performs correction positions X ₁ , and outputs the Y _1.

X ₁ = X ₀ + · Δt _n (5) Y ₁ = Y ₀ + · Δt _n (6) Here, n indicates that after the nth correction from the input.

The target azimuth calculation circuit 2 calculates the target azimuth θ (X ₁ , Y ₁ ) using the correction positions X ₁ and Y ₁ output from the track data correction circuit 1 based on the following equation.

The pseudo antenna azimuth calculation circuit 4 calculates the azimuth ω · Δt _n of the pseudo antenna when Δt has elapsed from the preset rotation angular velocity ω of the pseudo antenna and the time Δt _n output from the time generation circuit 3. is there.

The azimuth difference determination circuit 5 calculates the azimuth difference Δθ between the target azimuth θ (X ₁ , Y ₁ ) output from the target azimuth calculation circuit 2 and the azimuth ω · Δt _n output from the pseudo antenna azimuth calculation circuit 4 first. It is determined by the formula.

Δθ = ω · Δt _n −θ (X ₁ , Y ₁ ) (8) According to the value of Δθ, the time Δt generated by the time generating circuit 3 according to Table 1 and the availability of the output of the plot data generating circuit 6 Is output. In Table 1, σ indicates an allowable value of the azimuth difference Δθ, which is an azimuth error, and is a value that is set in advance and is a positive number (including 0).
It is.

The time generation circuit 3 uses the control signal output from the azimuth difference determination circuit 5 under the conditions shown in Table 1 to determine which of the correction times Δt _n calculated by the following equation (9) or (10). And outputs the time correction value δt _n calculated by the equation (11) to the (n + 1) th complement. Keep it for positive.

Here, Δt _n and δt _n indicate a corrected time output and a time correction value after the n-th correction counted from the time when the track data (X ₀ , Y ₀ ,) is input, respectively, where n is a natural number. And Where Δt ₁ and δt ₁ are the correction time output and the time correction value when the track data is input, respectively. Is calculated. θ (X ₀ , Y ₀ ) is calculated by equation (7).

When the track data (X ₀ , Y ₀ ,) is input, the track data correction circuit 1 uses the correction time Δt ₁ calculated by the equation (12) to calculate X based on the equations (5) and (6). ₁ , Y ₁
Is calculated and output, and the target azimuth calculation circuit 2 calculates the target azimuth θ (X ₁ , Y ₁ ). This value is compared with ω · Δt ₁ output from the pseudo antenna azimuth calculating circuit 4 by the azimuth difference judging circuit 5, and it is judged from the magnitude relation whether or not correction is necessary again according to Table 1. In the upper part of Table 1, the azimuth difference Δθ exceeds the negative permissible limit (lower limit of permissible value), and shows the case where the azimuth of the antenna has not yet “caught up” with the target azimuth, and the correction time Δt A little larger so that it falls within the tolerance Then, the direction difference is compared again. The middle row shows a case where the azimuth difference Δθ is within the allowable value, and the current correction position (X ₁ , Y ₁ ) may be output as plot data as it is. The lower stage shows a case where the azimuth difference Δθ has exceeded the positive allowable limit, and shows the case where the azimuth of the antenna "overtakes" the target azimuth. Then, the direction difference is compared again.

(Effect of the Invention) As described above, according to the present invention, the correction is repeated while finely adjusting the correction value recursively and stepwise, and the azimuth difference Δθ can be calculated analytically from the track data by driving the azimuth difference Δθ to a predetermined allowable value. There is an effect that the plot data is approximately calculated and data with higher accuracy than the conventional method can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.
FIG. 3 is a schematic explanatory diagram of a function of converting the track data to generate the pseudo plot data, and FIG. 3 is an explanatory diagram for expressing the relationship between the track data and the plot data by a mathematical expression. 1 track data correction circuit, 2 target azimuth calculation circuit, 3 time generation circuit, 4 pseudo antenna direction calculation circuit, 5 azimuth difference determination circuit, 6 plot data generation circuit.

Claims (1)

(57) [Claims] 1. Track data correcting means for correcting the input radar target track data based on its position information, speed information and correction time information; target azimuth for calculating the azimuth from the corrected track data. Calculating means; assuming a simulated antenna, calculating the azimuth of the antenna from the rotational speed and the correction time information; calculating the difference between the calculated target azimuth and the azimuth of the antenna, and calculating the azimuth difference A control signal for determining the amount of time correction from the magnitude of the azimuth and outputting an instruction control signal to generate plot data from the track data after the position correction when the azimuth difference becomes an appropriate value. Determining means; and a time generating means for generating and transmitting a correction time determined by the control signal from the azimuth difference determining means to the track data correcting means. Radar target information using the track data after the position correction from the track data correction unit and outputting plot data in response to an instruction control signal from the azimuth difference determination unit. Processing equipment.