JPH01102384A - Receiver for guided flight body - Google Patents

Abstract

PURPOSE:To instantaneously catch a target, by providing a memory circuit for storing the target speed data sent from ground radar before launching a guided light body and controlling the sweep range of a sweep circuit on the basis of the target speed data. CONSTITUTION:A memory 12 stores the speed data of a target from an interface 11 and controls the sweep range of a sweep circuit 8 before the launching of a guided flight body. The sweep range of the circuit 8 controlled by the memory 12 is narrowed in a frequency width because only the vicinity of the target speed data obtained by radar 10 is searched. With this, the time required in one sweeping is also shortened. The output of the circuit 8 is amplified by a DC amplifier 7 to be inputted to a mixer 2 through a voltage control oscillator 3. The reflected wave signal from the target received by an antenna 1 and the output from the oscillator 3 are mixed in the mixer 2 to output an intermediate frequency signal and the output thereof is amplified by an intermediate frequency amplifier 4 and, at the same time, unnecessary noise is attenuated and the target is detected in high detection probability by a signal detection circuit 9.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a receiver for a guided flying vehicle. More specifically, we propose a reception method that instantly captures Doppler information contained in reflected waves from moving targets.

[Conventional technology]

Figure 3 is a diagram showing the configuration of a conventional guided spacecraft receiver, where (1) is an antenna, (21 is a mixer, and (3) is a receiver for a guided spacecraft.
is a voltage controlled oscillator, (4) is an intermediate frequency amplifier, (5) is a frequency discriminator, (6) is a switch, (7) is a DC amplifier, (8) is a sweep circuit, and (9) is a signal detection circuit. .

Next, an example of the operation of the conventional receiver will be explained using FIG.

The antenna (υ) receives the reflected wave from the target, and the mixer (2) mixes the reflected wave signal from the target received by the antenna (1) with the output of the voltage controlled oscillator (3), which will be described later. The voltage controlled oscillator (3) outputs an intermediate frequency signal that is the difference between the frequency of the signal received in (1) and the output frequency of the voltage controlled oscillator (3). The frequency is controlled by a narrow band intermediate frequency amplifier (4) at the same time as amplifying the output of the nimixer (2).

Attenuates unnecessary noise. The bandwidth of the intermediate frequency amplifier (4) is narrow, usually less than 2 KH, S/J, in order to improve the signal-to-noise ratio, but is not particularly determined. The frequency discriminator (5) generates a DC voltage proportional to the frequency of the input;
The center frequency of the intermediate frequency amplifier (4) and the frequency discriminator (5)
) are the same, so if the frequency of the signal obtained from the output of the mixer (2) and the center frequency of the intermediate frequency amplifier (4) are the same, the output of the 9-frequency discriminator (5) becomes zero, and if they do not match, a DC voltage proportional to the difference between the output frequency of the mixer (2) and the center frequency of the intermediate frequency amplifier (4) is output from the frequency discriminator (5).

Further, when the frequency of the signal obtained from the output of the mixer (2) is not within the bandwidth of the intermediate frequency amplifier (4), the output of the 1-frequency discriminator (5) becomes zero. The switch (6) is controlled by a signal detection circuit (9) to be described later, and when the output frequency of the mixer (2) is within the bandwidth of the intermediate frequency amplifier (4), the switch (6) is controlled by a 9-frequency discriminator (5) and a DC signal to be described later. It operates so that the amplifier (7) is connected, and when the output frequency of the mixer (2) is not within the bandwidth of the intermediate frequency amplifier (4), the 9 frequency discriminator (5) and the DC amplifier (7) are disconnected. works. The DC voltage that is the output of the frequency discriminator (5) is applied to the switch (6
) is sent to the DC amplifier (7). When the DC amplifier (7) is connected to the frequency discriminator (5) by the switch (6), it amplifies the output voltage of the 9-frequency discriminator (5), and when it is not connected, it amplifies the output voltage of the frequency discriminator (5), which will be described later. 8
) amplify the output. The voltage controlled oscillator (3) outputs a frequency proportional to the output voltage of the DC amplifier (7).

Mixer (2), intermediate frequency amplifier (4), 1 frequency discriminator (
5).

Switch (6), DC amplifier (7), voltage controlled oscillator (
3) Ha.

An automatic frequency control circuit is constructed and operates so that the output frequency of the mixer (2) always becomes the center frequency of the intermediate frequency amplifier (4). That is, it operates to track the Doppler frequency of the reflected wave from the target.

Next, the operation when capturing the Doppler frequency included in the reflected wave from the target will be explained. The sweep circuit (8) outputs a voltage having a sawtooth waveform shown in FIG. 4 (,). The voltage width on the vertical axis of the waveform is determined by the frequency width to be searched, and conventionally the entire range from low-speed targets to high-speed targets was searched. Moreover, the horizontal axis shows the time involved in the search. The DC amplifier (7) amplifies the output of the sweep circuit (8) and outputs the voltage controlled oscillator (3).
).

The voltage controlled oscillator (3) outputs a wave number frequency shown in FIG. 4(b). The vertical axis is the output frequency width determined by the speed range of the target to be searched. The intermediate frequency amplifier (4) receives the intermediate frequency output from the mixer (2) as shown in FIG. 4(C), and converts it into the BXF (intermediate frequency bandwidth) shown in FIG. 4(b). Amplify only the frequency signals within the range. The output voltage amplified by the signal detection circuit (9) intermediate frequency amplifier (4) is shown in Figure 4 (
As shown in the waveform shown in d), when the threshold value is exceeded, the frequency discriminator (5) and the DC amplifier (7) are connected to the switch (6), and when the threshold value is not exceeded, the frequency The discriminator (5) and DC amplifier (7) are controlled to be removed.

mixer (2), intermediate frequency amplifier (4), signal detection circuit (
9).

A sweep circuit (8), a DC amplifier (7), and a voltage controlled oscillator (3) are configured to capture the Doppler frequency included in the reflected wave from the target.

Thus, prior art devices, after launching a guided projectile, searched the entire range of target speeds, from the lowest to highest speeds, that could be expected of such a device. It took a long time for my friend to track the target. Furthermore, there is a problem in that if a -degree acquisition fails, it takes a long time to acquire the next acquisition.

[Problem that the invention seeks to solve]

Conventionally, after launching a guided projectile, the search for a target's Doppler frequency begins, searching for Doppler frequencies corresponding to the expected target's lowest to highest speeds. As a result, it took a long time to acquire the target, and the interception range became narrower. In addition, because the search was conducted over a wide area, if the target failed to be acquired, it would take some time to acquire it again, and during that time, the target would evade the target. This invention was made to solve the above-mentioned problems, and provides a receiver for guided aircraft that can shorten the target acquisition time by narrowing the target search range after launching a guided aircraft. The purpose is to obtain.

[Means for solving problems]

The receiver for guided aircraft according to the present invention uses a combinator on the ground to calculate the expected outward flight path of the guided aircraft based on information obtained from radar on the ground before launching the guided aircraft. It memorizes predicted Dotsupura information before firing, minimizing the search area. This allows the target to be captured instantly after launch.

[For production]

In this invention, before launching the guided missile, information obtained by ground radar is calculated and stored in memory. I'm sorry about this.

Since the search range after launching a guided projectile is reduced, the target can be captured instantly.

〔Example〕

An example of the operation of the receiver for guided aircraft according to the present invention is shown in FIG. 1 below. (1) to (9) are the same as in FIG. 3, and therefore will be omitted. (IQ+ is a ground radar and collects information about the target. The circle is an interface and is a circuit for inputting the speed information of the target collected by the ground radar a to the guided flying vehicle. It is a memory that stores target velocity information from interface αB, and executes a sweep circuit (
8) to control the sweep range.

Note that the interface (111) may be incorporated into a guided missile or a radar, and is not limited to 1%.The sweep range of the sweep circuit (8) controlled by the memory (2) is As shown in Figure 2 (a), compared to Figure 4 (a) of the conventional sweep range, the voltage width on the vertical axis is In the receiver according to the present invention, the search is performed only in the vicinity of the target speed information obtained by the radar.

The frequency width is narrower. Additionally, the time required for one sweep has also become shorter.

The output of the sweep circuit (8) is amplified by a DC amplifier (7) and input to the voltage controlled oscillator (3). The voltage controlled oscillator (3) outputs a waveform shown in FIG. 2(b).

The intermediate frequency amplifier (4) outputs the waveform shown in FIG. 2(c). Like the conventional device, this inputs the intermediate frequency output from the mixer (2), and amplifies the frequency signal that falls within the intermediate frequency bandwidth B□ in Figure 2(b). . Furthermore, compared to the conventional waveform shown in FIG. 4(C), the number of times the target is searched within the same time is greater.

As shown in FIG. 2(d), the output waveform of the signal detection circuit (9) also exceeds the threshold many times within the same period of time.

That is, the target detection probability is high.

〔Effect of the invention〕

As described above, according to the present invention, the target search range can be narrowed and the target can be captured instantly.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a receiver for guided aircraft of the present invention;
Fig. 2 is a diagram showing waveforms of the receiver for guided spacecraft according to the present invention, Fig. 3 is a diagram showing a conventional receiver for guided spacecraft, and Fig. 4 is a diagram showing the conventional receiver for guided spacecraft. FIG. In the figure, (1) is an antenna, (2) is a mixer, +31i voltage controlled oscillator, (4) is an intermediate frequency amplifier, and (5) is a frequency discriminator. (6) is a switch, (7) is a DC amplifier, +8)fl
(9) is a signal detection circuit, (9) is a ground radar, (111 is an interface, and C12 is a memory. In Figure 9, the same or corresponding parts are indicated by the same reference numerals.

Claims (1)

[Claims] A voltage controlled oscillator that outputs a frequency proportional to the input voltage,
a mixer that mixes the reflected wave signal from the target received by the antenna and the output of the voltage controlled oscillator to output an intermediate frequency signal; an intermediate frequency amplifier that amplifies the output signal of the mixer; a frequency discriminator that generates a DC voltage proportional to the frequency of the output signal; a sweep circuit that generates a sawtooth wave; amplify the output voltage of the frequency discriminator or the output voltage of the sweep circuit; A DC amplifier that outputs to the voltage controlled oscillator, a switch connected between the output terminal of the frequency discriminator and the input terminal of the DC amplifier, and an input terminal of the intermediate frequency amplifier to receive Doppler information from the target. When the output voltage of the intermediate frequency amplifier is greater than the threshold value, the switch is turned on and the operation of the sweep circuit is turned off; when the output voltage of the intermediate frequency amplifier is smaller than the threshold value, the switch is turned off and the sweep circuit is turned off. A receiver for a guided spacecraft equipped with a signal detection circuit that turns on the operation of the circuit, stores target speed information sent from a ground radar before launching the guided spacecraft, and uses that target speed information to A receiver for a guided spacecraft characterized by being provided with a memory circuit for controlling the sweep range of a sweep circuit.