JPS59192984A - Radar transmitter - Google Patents

Abstract

PURPOSE:To exclude electron disturbance by controlling the variable period of an oscillation frequency on a double random basis and varying a transmission frequency irregularly. CONSTITUTION:A random signal generating circuit 5 is a noise generating circuit which utilizes the thermal noise, etc., of a diode, and its output signal varies at random as shown in a figure (a). The output signal of the circuit 5 is impressed to a sample holding circuit 5, and the signal of a random signal generating circuit 8 similar to the circuit 5 is impressed to a timing circuit 7 respectively. The circuit 7 outputs timing pulses which vary in interval in responding with the output signal of the circuit 8 as shown in a figure (c), and the output of the circuit 5 is sampled by the circuit 6 by the timing signal of the circuit 7 to obtain the output of the circuit 6 as shown in a figure (d). The output of the circuit 6 is converted by a servoamplifier 3 into a sine wave signal which varies in an amplitude at random at every randomized interval as shown in a figure (d), and a tuning mechanism 2 varies the frequency of a magnetron 1 at a speed proportional to the signal of the amplifier 3.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a radar transmitter that changes transmission frequency.

A conventional transmitter of this type is shown in FIG.

In Fig. 1, (1) is a magnetron for generating microwave signals, (2) is a tuning mechanism attached to the magnetron (1), and (3) is a servo amplifier for driving the tuning mechanism (2). , (4) is a constant voltage source for generating a constant voltage signal.Next, the operation of the conventional radar transmitter will be explained with reference to FIG. A constant voltage signal from a constant voltage source (4) as shown in FIG. 2(a) is converted by a servo amplifier (31K) into a sinusoidal signal with a constant amplitude value as shown in FIG. 2(b). The tuning mechanism (2) changes the oscillation frequency of the magnetron (1) sinusoidally at a constant cycle at a speed proportional to the amplitude value of the signal from the servo amplifier (3) as shown in FIG. 2(C).

Since conventional radar transmitters are configured as described above, the change period of the magnetron's oscillation frequency is uniform, and as a radar transmitter, the oscillation frequency cannot be easily identified, making it susceptible to electronic interference. There were other drawbacks.

The present invention has been made in order to improve these drawbacks, and provides a radar transmitter that is less susceptible to electronic interference by changing the period of change of one oscillation frequency extremely randomly.

An embodiment of the present invention shown in FIGS. 3 and 4 will be described below. In FIG. 3, (1) to (3) are the same as in FIG. (5) is a random signal generating circuit shown in FIG. 1, which generates a signal whose voltage value changes randomly. (6) is a sample hold circuit that samples the signal from the first random signal generation circuit (5) and holds the output value for a certain period of time; (7) is the sample hold circuit (6); A timing circuit (8) is a second random signal generating circuit that generates a random signal and controls the timing of the timing circuit (7).

Next, the operation will be explained in detail.

The first random signal generation circuit (5) is a noise generation circuit that utilizes thermal noise of a diode.

The output signal changes randomly as shown in FIG. 4(a). This random signal is applied to a sample and hold circuit (6).

The second random signal generating circuit (8) is a circuit similar to the random signal generating circuit (5), and generates a random signal as shown in FIG. 4(b). The signal of this second random signal generation circuit (8) is applied to the timing circuit (7). The timing circuit (7) outputs timing pulses whose output pulse intervals vary randomly according to the output signal of the random signal generator (8), as shown in FIG. 4(C). .

The output of the first random signal generation circuit (5) is sent to the sample and hold circuit (6)K, and then to the timing circuit (5).
7) is sampled by the timing signal from 7). As a result, as shown in FIG. 4(d), a signal in which the voltage value of the sampled random signal is held for a period of random intervals is obtained as the output of the sample and hold circuit (6). The output of (6) is
The servo amplifier (3) converts the signal into a sine wave signal whose amplitude changes randomly at random intervals as shown in FIG. 4(e). The tuning mechanism (2) includes the servo amplifier (
3) Change the oscillation frequency of the magnetron (11) at a speed proportional to the signal from the magnetron.

As a result, the period of change in the oscillation frequency of the magnetron (1) changes randomly at random intervals, as shown in FIG. 4(f).

In this way, this invention doubles and randomly controls the change period of the magnetron's oscillation frequency, so the change in the oscillation frequency' is extremely irregular, and as a radar transmitter, it is difficult to oscillate for the other party's radar. Because the frequency is extremely difficult to predict, it can be applied to radar transmitters that are extremely resistant to electronic interference.

As described above, according to the present invention, since the transmission frequency of the radar transmitter can be changed extremely irregularly, there is an advantage that the radar transmitter can be constructed which is less susceptible to electronic interference.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a conventional radar transmitter, FIG. 2 is an output waveform diagram of the radar transmitter shown in FIG. 1, and FIG. 3 is a diagram showing an embodiment of the radar transmitter according to the present invention. FIG. 4 is an output waveform diagram of the radar transmitter according to the present invention. In the diagram, (1) is the magnetron, (2) is the tuning mechanism, and (3)
is a servo amplifier, (4) is a constant voltage source, (5) is a first random signal generator, and (6) is a sample and hold circuit. (7) is a timing circuit, and (8) is a second random signal generation circuit. In FIG. 9, the same parts are designated by the same reference numerals. Agent Masuo Oiwa Figure 1 Figure 2 Figure 3 Figure 4. )”-mouth”-””-L”yu (d) □□

Claims (1)

[Claims] A magnetron that generates microwave signals. In a radar transmitter having a tuning mechanism that changes the oscillation frequency of the magnetron and a servo amplifier that drives the tuning mechanism, a first random signal generation circuit that generates a random signal; a sample-and-hold circuit that samples a random signal and holds the output value for a certain period of time; a timing circuit that controls the sampling timing of the sample-and-hold circuit; and a random signal that controls the timing of the timing circuit. A second random signal generation circuit is provided, and by applying a sample and hold signal from the sample and hold circuit to the tuning mechanism of the magnetron via the servo amplifier, the rotational speed of the tuning mechanism is randomly changed. A radar transmitter, characterized in that the period of change of the oscillation frequency of the magnetron is changed randomly.