JPH05100020A - Target capturing method for missile - Google Patents

Abstract

PURPOSE:To provide a target capturing method for missile, with which capture can be made certainly even though the missile does not emit electric wave. CONSTITUTION:A direct wave A from another radar R and an indirect wave B reflected by a target T are received by a passive radar of a flying object M, and the incoming angles thetaR, thetaT of these electric waves are sensed. The time difference DELTAt between the two incoming waves is sensed, and the target position coordinates (x, y) are determined from the distance LR to the other radar R, the wave incoming angles thetaR, thetaT, and this time difference DELTAt obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for capturing a target in a flying object used as a means for making the flying object reach a target.

[0002]

2. Description of the Related Art Conventionally, a flying object having, for example, a passive radar receives radio waves radiated from a target itself and guides the flight direction to the strongest direction of the received signal to capture and reach the target.

FIG. 6 shows a conventional target capturing state in a flying object, that is, the flying object M receives a radar wave radiated from a radar R mounted on a target T to perform target acquisition. ..

[0004]

Therefore, the conventional target capturing method for a flying object having a passive radar is effective only for a target accompanied by radio wave emission such as radar waves, but for example, even for a target performing radio wave emission. However, if the radio control is performed or the radio emission is stopped, there is a drawback that the target cannot be captured immediately.

The present invention has been made in view of the above problems,
It is an object of the present invention to provide a target capturing method for a flying object that can reliably capture the target even if the target does not emit radio waves.

[0006]

That is, a target capturing method for a flying object according to the present invention is a first capturing method for capturing a target based on a radio wave emitted from the target when the target itself emits radio waves. And means for capturing the target based on the direct wave from the radar other than the target and the indirect wave reflected by the target when the target itself does not emit radio waves. is there.

[0007]

In other words, the target position coordinate is determined based on the reception time difference and the arrival angle of the direct wave of the radar from the third position other than the flying object and the target and the indirect wave due to the target reflection to the flying object, and the radar position information. It will be indexed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a target capturing state of a flying object M having a passive radar. In FIG. 1, T is a target, 1 is a ship radar, 2 is a ground radar, 3 is an aviation radar, and a solid line A Is a flying object M from each of the above radars 1, 2 and 3.
Is a direct wave received directly with respect to the above, and the broken line B is an indirect wave reflected by the target T from the radars 1, 2 and 3 and received by the flying object M.

Here, in the flying body M, for example, a direct wave A from the ground radar 2 and an indirect wave B passing through the target T thereof are received by a passive radar installed in advance, and first, the direct wave A and the indirect wave are received. Wave arrival angle of each wave B θR
, ΘT is detected.

FIG. 2 is a diagram showing the arrival angle θ R of the direct wave A from the radar R with respect to the flying object M and the arrival angle θ T of the indirect wave B reflected on the target T. The distance between the flying object M and the radar R is shown in FIG. LR, the distance between the radar R and the target T is D1, the target T
The distance between the flying body M and the flying body M is D2, and the position coordinates of the radar R corresponding to the distance LR are set in advance in the database of the target capturing system of the flying body M. Further, in the flying object M, it is determined whether or not the direct wave A from the radar R and the indirect wave B via the target T have the same pulse signal, and the arrival time difference Δt is detected. FIG. 3 is a diagram showing the arrival time difference Δt between the direct wave A and the indirect wave B from the radar R in the flying object M, and the following equation (1) is established based on the arrival time difference Δt. .DELTA.t = (D1 + D2-LR) / V (1) where V is the radio wave propagation velocity.

FIG. 4 is a block diagram showing a correlation time difference detection circuit for the direct wave A and the indirect wave B from the radar R in the flying object M.
The direct wave A and the indirect wave B input to the (Seeker) are directly supplied to the correlator 11 on the one hand, and are sequentially supplied to the correlator 11 via the delay timer 12 on the other hand so that each of the incoming radio waves The output determination circuit 13 determines whether the pulse signals match.
Is detected and determined.

In this case, the arrival time difference Δt between the direct wave A and the indirect wave B is detected by the delay timer 12 and when the output judging circuit 13 judges that the signals match, the delay time detecting section 14 Detected in.

FIG. 5 shows the position coordinates of the radar R and the target T with respect to the flying object M. In the flying object M, the distance LR with respect to the radar R, the arrival angle θ R of the direct wave A, and the arrival angle of the indirect wave B. When θ T and the arrival time difference Δt thereof are known, the position coordinate of the target T is calculated by the following equation (4) based on the elliptic relational expressions in the following equations (2) and (3). Here, the following equation (2) is obtained using the above equation (1). r = (D1 + D2 -LR) / 2 (2) (x-a / 2) ² / (A / 2 + r) ² + y ² / {R (a + r)} = 1 Equation (3) y = x tan θ Equation (4) As a result, the flight direction of the flying object M is guided according to the position coordinates (x, y) of the target T. , The flying body M surely reaches the target T.

On the other hand, the distance L between the flying object M and the radar R
If R is unknown and the position coordinate of the target T cannot be obtained,
The flying object M is guided in the direction in which the received signal strength of the indirect wave B is strongest, and reaches the target T.

Therefore, according to the target capturing method for the flying object as described above, the direct wave A from the other radar R and the target T received by the passive radar of the flying object M are obtained.
Angle of arrival θR, θT with indirect wave B reflected by
And the time difference Δt of each incoming radio wave,
The position coordinate (x, y) of the target T is obtained based on the distance LR to the other radar R, the radio wave arrival angles θR and θT of the direct wave A and the indirect wave B, and the radio wave arrival time difference Δt. Therefore, even if the target T itself does not emit radio waves, the target T can be reliably captured and the flying body M can be reached.

In the above embodiment, when there are a plurality of targets, the target coordinates are selectively captured according to the received signal strength of the indirect wave corresponding to each target, and the flight direction thereof is guided. become.

[0018]

As described above, according to the present invention, when radio waves are emitted from the target itself, the first capturing means for capturing the target based on the radio wave radiated from the target and the radio wave from the target itself. When the target is not radiated, a second capturing means for capturing the target based on the direct wave from the radar other than the target and the indirect wave reflected by the target is provided. However, the target can be reliably captured.

[Brief description of drawings]

FIG. 1 is a diagram showing a target capturing state of a flying object M having a passive radar according to an embodiment of the present invention.

2 is an arrival angle θ R of a direct wave A from a radar R to a flying object M and an arrival angle θ of an indirect wave B reflected on a target T.
Diagram showing T.

FIG. 3 is a diagram showing arrival time difference Δt between a direct wave A and an indirect wave B from a radar R in a flying object M.

FIG. 4 is a block diagram showing a correlation time difference detection circuit for a direct wave A and an indirect wave B from a radar R in a flying object M.

5 is a diagram showing position coordinates of a radar R and a target T with respect to a flying object M. FIG.

FIG. 6 is a view showing a conventional target capturing state in a flying object.

[Explanation of symbols]

M ... Flying object, T ... Target, R ... Radar, A ... Direct wave, B ...
Indirect wave, Δt ... Arrival time difference of direct / indirect wave, LR ... Radar distance, θR ... Direct wave arrival angle, θT ... Indirect wave arrival angle,
x, y ... Target position coordinates.

Claims (1)

[Claims] 1. When the target itself radiates radio waves, first capturing means for capturing the target based on the radiated radio waves from the target, and when the target itself does not radiate radio waves, A target capturing method for a flying object, comprising: a second capturing unit that captures the target based on a direct wave from a radar other than the target and an indirect wave reflected by the target.