JPS6154479A - Target tracking system - Google Patents

Abstract

PURPOSE:To extend the detection and acquisition range of a target by a passive system and improve target tracking performance at a short range and an extremely short range by performing active tracking operation and passive tracking operation on time-division basis. CONSTITUTION:This system is equipped with an antenna 1, radio wave duplexer 2, transmitter 3, receiver 5 which receives and detects a receive signal on active bases, and receiver 6 which receives and detects a receive signal on passive basis. Further, a timing generator 13 generates a signal for switching both receivers and an active/passing switch 4 performs switching operation according to the indication; and an active/passive angle error detector 14 detects an angle error signal from outputs of the active receiver 5 and passive receiver 6 and a reception system switching decision device 15 judges whether switching to the passive reception system is effective or not. The reception system switching decision device 15 compares the level of a preset reference signal So with that of the detection signal Sp of the passive receiver and makes a decision to perform passive system tracking, for example, when So<=Sp.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a target tracking system, and particularly to a tracking system for tracking a target that reflects or emits electromagnetic waves.

(Prior Art) Conventionally, when creating a tracking device using the eye tracking method to detect and capture this type of target, the active method and passive method tracking device (hereinafter referred to as "active/
It's called a passive tracking device. ) was adopted. 14
The device shown in the figure initially detects targets at long distances,
(1! In order to improve the I prompt, the transmitting/receiving switching signal generator 12
The transmitter/receiver switch 2 is switched to the transmitter side, and the electromagnetic waves (hereinafter referred to as "radio waves") generated from the transmitter 3 are transferred to the antenna 1.
After that, the transmitter/receiver switch 2 is switched to the receiving side. Radio waves emitted from the antenna 1 are reflected by the target, background, etc. (hereinafter referred to as "target, etc."). A part of the reflected signal (hereinafter referred to as 1 reflected reception signal) passes through the antenna 1 and passes through a path that is switched to the active side by the active/passive switch 4, and the number of active receptions is 5.
After processing such as signal detection, active/
Azimuth error and elevation angle error (hereinafter referred to as "error angle") are detected by the angle error detector 8 via the passive switch 7, and a tracking signal is generated.The signal is amplified by the servo amplifier 9, and the servo drive device 10 performs active eye-off tracking toward the antenna axis or the like.

However, in the active method, when tracking a target at close range or close range, the fluctuations in the foul reception signal and the fluctuations in the error angle signal (hereinafter referred to as "signal fluctuations") become large, making it difficult to obtain and track J111 properly. It may not be possible.

On the other hand, the passive method receives weak radio waves emitted and reflected by the target, so the distance at which it can detect the target is short;
The short-range target tracking performance is good because the signal fluctuation is small. Therefore, when a target detected and captured using the active method at a distance of 2000 yen approaches at a short distance, it is necessary to switch the tracking method from the active method to the passive method to obtain good tracking characteristics.

Switching from the active method to the passive method is performed based on the switching distance Re set in advance in the switching signal generator 11 in the active/passive tracking device shown in Fig. 4, and the distance between the active/passive tracking device and the target measured by the active method. The distance Rt is compared, and when Rc≧Rt is satisfied, switching to the passive method is performed. That is, the active/passive switch 4.7 is switched to the passive side, and tracking is performed using the passive receiver 6.

(Problem to be solved by the invention, α) However, the magnitude of the target reception signal (hereinafter referred to as the "radiated reception signal") in the passive method is subject to fluctuations depending on environmental conditions such as weather. Because of this, moody negative effects y2. Under these conditions, there may be cases where the target cannot be detected or captured even if Re≧Rt. To avoid this situation,
Since it is required to set Rc to a small value, the tracking effect of the passive method is reduced, and its performance cannot be fully demonstrated.

(Means for Resolving Problems) The present invention provides active tracking means and passive tracking means for obtaining a target angular error signal from electromagnetic waves reflected and emitted by the target, and also provides active tracking operation and passive tracking means. This aims to provide a target tracking method that extends the target detection and acquisition distance using a passive method and improves target tracking performance at close range and close range by executing the tracking operation of the method in a time-sharing manner. It is.

(Function) In the present invention, target detection using a passive method in a target tracking method using an active method and a passive method (hereinafter referred to as "active/passive tracking method");
In order to extend the acquisition distance and reduce the deterioration of target tracking performance at the appropriate pressure ^IF and close range, the timing generator 13 shown in FIG.
), the active method operation and the passive method operation are executed in a time-sharing manner within one cycle. As a result, the effectiveness of the passive tracking method is increased by optimizing and maximizing the distance at which the passive tracking method can capture and track a target under the influence of the environment such as weather and other factors.

(Purchase of the Invention) The present invention is characterized in that target acquisition and tracking distance in the passive method can be extended by continuously executing the active method operation and the passive method operation within one cycle. There is.

The purchase of the present invention includes an antenna 1, a radio wave transmitter/receiver switch 2, a transmitter 3, and a receiver that receives a received signal by an active method.
Receiver for detection (hereinafter referred to as "active receiver")
5, a receiver (hereinafter referred to as "passive receiver") 6 that receives and detects a received signal by a passive method, a timing generator 13 that generates a signal to switch and operate both of these receivers, and An active type/nosive reception type switch 4 that can be switched in response to an instruction, an active/passive angular error detector 14 that detects an angular error signal from the outputs of the active receiver 5 and the passive receiver 6, and an active/passive angle error detector 14 that can be switched to an active type reception type. It is equipped with a receiving method switching discriminator 15 that determines whether or not the reception method is valid.The receiving method switching discriminator 15 compares a preset reference signal So with the magnitude of the detected signal sp of the passive receiver and makes a decision. For example, when SO≦Sp, passive tracking is executed.

(Embodiments of the Invention) Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Reference is made to FIG. 1, which shows a block diagram of an active and passive tracking device according to the present invention, and to FIG. 2, which shows device states and signal waveforms.

Aim antenna 1 at the target object at time T. The instruction signal (2n) of the transmission/reception switching signal generator 12 causes the transmission/reception switching device 2 (
The transmitter 3 switches to transmission 1...1 as shown in 2-b) and emits radio waves as shown in (2-c) at time T1. Thereafter, the transmission/reception switching device 2 is switched to the receiving side as shown in (2-b) at time T2 by the instruction signal (2-a) of the transmission/reception switching signal generator 12. The active/passive switch 4 is activated at time T.
. From T. According to the instruction (2-d) of the timing generator 13 to time-divide one period of +Tn at time T3, (2-d)
As shown in e), the initial value is set on the active receiver 5 side, and the reflected received signal (2-f) is sent to the active receiver 5.
The target signal is detected, and the active/passive angular error detector 14 outputs an angular error signal (2-g) indicating the position of the target.

After a certain period of time Td elapses after the radio wave is emitted, the timing generator 13
According to the instructions, the active/passive switch 4 (2-e
), by switching to the passive receiver 6 side, the radiated reception signal (2-h) enters the passive receiver 6,
The target signal is detected, and the angle error detector 14 outputs an angle error signal (2i) indicating the position of the target. The target signal Sp detected in the passive receiver is input to the reception method switching discriminator 15, where it is compared with a preset reference value So and judged. If the Sp intensity is sufficiently large compared to So, the passive method is selected. The angular error signal (2-i), which is the output of the angular error detector 1. to track the target. If the reception method switching discriminator 15 determines that the strength of Sp is weaker than that of SO, the angular error signal (2-g) of the active method held is amplified by the servo amplifier 9, and the servo drive device 10 By inputting , the antenna 1 is driven to perform target tracking such that the angular error is minimized.

By configuring the configuration as described above, it is possible to capture and track targets at the maximum distance using a passive method, which is difficult to grasp clearly in situations where environmental conditions such as weather change. The tracking point can be stabilized, and the effectiveness of the tracking device can be maintained.

In addition, in the arrangement of the target tracking device 16 shown in FIG.
The maximum acquisition and tracking distance using the passive method is approximately 20+
In the case of target (car) 17, which travels at n/hour, the distance was approximately 150 m on a clear day and approximately 100 m on a cloudy day.

(Description of effects of the embodiment) As explained above, the above embodiment includes the antenna 1, the transmitter 3, the active receiver 5, the passive receiver 6, the active/passive angle error detector 14, and the timing generator 13. By combining the receiving method switching discriminator 15 with the receiving method switching discriminator 15, the operation for capturing and tracking the target by the active method is carried out, and the receiving method switching discriminator 15 which discriminates the magnitude of the target detection signal 46 of the passive receiver. Since the target tracking method is switched between active and passive depending on the judgment, it is possible to always provide a passive tracking method that is stable at the maximum distance under the given conditions, regardless of changes in environmental conditions such as weather. It is simple and easy to incorporate into conventional tracking devices, and enables stable tracking that is not affected by radio wave interference at the true target. Moreover, by adopting this configuration, it is also possible to apply tracking using only an active method or tracking using only a passive method depending on the situation.

(Explanation of other embodiments of the invention and examples of diversion to other uses) In the above embodiment, passive mode operation is performed between the time of radio wave transmission in active mode operation and the time before the next radio wave transmission. Although described in the above-mentioned method, a method in which active operation is performed two or more times and then passive operation is performed also produces similar effects. Furthermore, even after acquisition and tracking by the passive method has become possible, using the active method and the passive method in combination can produce the same effect under conditions such as radio wave interference or dissemination of false targets.

By utilizing the angular error signal, the tracking device according to this method can achieve the same effect even when used in a guidance method for guided bullets and artillery shells with similar procurement.

Further, in the above embodiment, the active reception and the passive reception number were explained separately, but the same effect can be obtained by using both the active method and the passive method for the reception number.

(Effects of the Invention) As explained above, according to the target tracking method of the present invention,
An active force type tracking means and a passive type tracking means are provided to obtain an angular error signal of the target from electromagnetic waves reflected and emitted by the target, and the active type tracking operation and the passive type tracking operation are executed in a time-sharing manner. Therefore, it is possible to extend the target detection and acquisition distance using the passive method and improve the target tracking performance at close range and close range.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram showing an embodiment of the target tracking method according to the present invention, Fig. 2 is an explanatory diagram showing an example of the signal waveform of each part in Fig. 1, and Fig. 3 shows the maximum target tracking distance in the passive method. An explanatory diagram showing a test method for confirmation, FIG. 4 is a configuration diagram of a conventional target tracking system. DESCRIPTION OF SYMBOLS 1... Antenna, 2... Transmission/reception switch, 3... Transmitter, 4... Active/passive switch, 5... Active receiver, 6... Number of passive receptions, 7...・Active/passive switch, 8... Angle error detector,
9... Servo amplifier, 1o... Servo drive device, 1
DESCRIPTION OF SYMBOLS 1... Switching signal generator, 12... Transmission/reception switching signal generator, 13... Timing generator, 14... Active/passive angle error detector, 15... Reception method switching discriminator, 16 ...Target tracking performance, 17...Target (automatic month 1).

Claims (1)

[Claims] (1) It is equipped with an active tracking means and a passive tracking means that obtain an angular error signal of the target from electromagnetic waves reflected and emitted by the target, and is capable of performing the active tracking operation and the passive tracking operation in a time-sharing manner. Characteristic target tracking method.