JPS6030901B2 - radio wave transmitter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a radio wave transmitting device that sends a predetermined radio wave signal to a tracking radar device that performs Doppler frequency tracking as well as range gate tracking to reduce the function of the tracking radar device.

FIG. 1 shows an example of the configuration of a radio wave transmitting device that reduces the functionality of a conventional tracking radar device.

In FIG. 1, an incoming radio wave from a tracking radar received by a receiving antenna 1 is amplified by a receiving circuit 2, and is stored in a frequency storage circuit 3 as it is at the frequency of the incoming radio wave. A transmission wave control switch 4 determines the transmission wave emission time of the signal stored in the frequency storage circuit 3, and the signal passes through a transmitter 5, becomes a transmission wave, and is emitted into the air from a transmission antenna 6. The control circuit 7 controls the storage time of the frequency storage circuit 3 and the transmission wave control switch 4. The transmitted wave E emitted into the air is received by the other party's tracking radar together with the tracking radar reflection signal R from the mother aircraft which transmits the signal to the transmitting device.

The tracking radar creates a range gate signal G in response to the reflected signal R, and performs functions such as distance measurement by tracking that signal. When there is a powerful transmission wave E, a distance gate signal G is created for the transmission wave E. Further, if the emission time of the transmitted wave E is sequentially delayed, the distance gate signal G also moves together with the transmitted wave E, and the distance measurement function of the tracking radar can be degraded. Figure 2 shows this situation. FIG. 2a shows the case where there is no transmitted wave E, and the distance gate signal G is created for the reflected signal R from the target. In FIG. 2b, since there is a powerful transmitted wave E in the immediate vicinity of the reflected signal R, a distance gate signal G is created for the transmitted wave E.
Figure 2 C shows the case where the transmitted wave E is delayed by T with respect to the reflected signal R, and the distance gate signal G is shifted by T with respect to the normal reflected signal, and there is an error in the measured distance by that amount. will occur. However, in addition to the distance gate tracking described above, recent tracking radars also have a tracking function for the Doppler frequency generated by the relative speed of the target and the tracking radar, and the configuration shown in Figure 1 is used. The radio wave transmitter has the disadvantage that it cannot affect a tracking radar having a Doppler frequency tracking function and degrade its function.

In order to eliminate these drawbacks, the present invention generates a transmission signal with a Doppler frequency by mixing a transmission Doppler signal with an incoming signal from a tracking radar, and a tracking radar for Doppler frequency tracking. The purpose of the present invention is to provide a radio wave transmitting device that can reduce the function of the radio wave transmitter.

An embodiment of the present invention will be explained with reference to FIG.

In the figure, numerals 1 to 6 have the same circuit configuration as in FIG. A first control circuit 7 sends control signals to the frequency storage circuit 3, the transmission wave control switch 4, and the second control circuit 8, respectively.

9 is a Doppler frequency oscillator, which is a feature of the present invention.

The oscillation output of this Doppler frequency oscillator 9 is mixed in a mixer 10 with the transmission wave emission signal sent through the transmission wave control switch 4. In the above embodiment, the signal output from the frequency storage circuit 3 that stores incoming radio waves from the tracking radar is input to the transmission wave control switch 4.

The transmission time is controlled by the transmission wave control switch 4, and the transmission time is controlled by the transmission wave control switch 4.
The impression force is set to 0. On the other hand, since the output from the Doppler frequency oscillator 9 is applied to the mixer 10, the mixer 10'
If this SSB (Single Side Band) mixer is used, the frequency of the output signal of the mixer 10 will be (Fo+AF), which is shifted from the frequency Fo of the incoming radio wave from the tracking radar by the oscillation frequency ΔF of the Doppler frequency oscillator 9.

Therefore, if a frequency deviation △F corresponding to the delay speed is given to the transmitted wave E that is emitted with a delay from the reflected signal R that is reflected by the base machine equipped with the radio wave transmitter, the tracking mechanism for the Doppler frequency on the tracking radar side will be affected. The transmitted wave E can be tracked even if

The second control circuit 8 has a function of oscillating a Dobra frequency corresponding to a rate of change in the delay time of a transmission wave E that is delayed and emitted with respect to a reflected signal R that is reflected by a mother machine etc. equipped with a radio wave transmitter. There is. In other words, if the rate of change in the delay column is V=, then the Doppler frequency △F corresponding to this rate of change is △
F: Fortress Mountain Umbrella (However, Koen C》V), and the situation is delayed m
．． A transmission wave E+ΔF is transmitted.

The above has described a radio wave transmitter that affects the tracking radar and degrades its function, but this radio wave transmitter can also have a large effect on the normal pulsed Doppler radar that detects the Doppler frequency and degrade its function. Needless to say, it is effective.

As described above, the radio wave transmitting device according to the present invention includes a Doppler frequency oscillator and a mixer that mixes the incoming radio wave from the partner radar and the signal from the Doppler frequency oscillator,
Since the frequency of the transmitted wave can be shifted by an arbitrary Doppler frequency, it has the effect of reducing the functionality of not only distance gate tracking but also Doppler frequency tracking tracking radar.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an example of the configuration of a conventional radio wave transmitter, Fig. 2 is a waveform diagram showing the relationship between the tracking radar reception signal and the distance gate in distance gate tracking, and Fig. 3 is the waveform diagram of the present invention. FIG. 2 is a block diagram showing one embodiment of the present invention. In the figure, 1 is a reception antenna, 2 is a reception circuit, 3 is a frequency storage circuit, 4 is a transmission wave control switch, 5 is a transmitter, 6 is a transmission antenna, 7 is a first control circuit, and 8 is a second control circuit ,
9 is a Doppler frequency oscillator and a 1-way mixer. Note that the same reference numerals in the figures indicate the same or equivalent parts. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1. A frequency storage circuit that stores the received signal at its frequency for each incoming radio wave, a transmission wave control switch that sequentially delays and emits this stored signal with respect to the reflected wave of the incoming radio wave, and a delay time of this emitted signal. A radio wave transmitter comprising: a Doppler frequency oscillator that generates a Doppler frequency shift corresponding to a rate of change of , a mixer that combines the emission signal and the Doppler frequency shift, and a transmitter that transmits the composite signal.