JPH052093U - Monopulse radar device - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] To eliminate the gain difference between signal systems over a wide band. [Structure] An AGC attenuator 15 for adjusting the level of a reference signal from an oscillator 14 to a radar signal in a free time other than the time required for one cycle of radar measurement, and a gate for creating a timing for inputting the reference signal to each mixer preamplifier. Generator 1
6, a gate circuit 17, and adders 18, 19 and 20 for inputting reference signals to the respective signal systems are input to the mixer preamplifiers 2, 3 and 4 of the respective signal systems, and the AGC amplifiers 5 and 5, respectively.
It passes through 6 and 7 and reaches the detection circuits 8, 10 and 12. The outputs of the detection circuit 8 are input to the AGC circuits 9, 11, 13 and the outputs of the detection circuits 10, 12 are input to the AGC circuits 11, 13, respectively. The output of the sum AGC circuit 9 is fed back to the sum AGC amplifier 5 as it is, but the difference AGC circuits 11 and 13 are used.
The output of is added to the output of the AGC circuit 9 by the AGC voltage adders 21 and 22 for adding the detected AGC signal, and is fed back to the difference AGC amplifiers 6 and 7, respectively.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This invention is, for example, a radar device for radiating and reflecting an electromagnetic wave to a target to be detected, extracting necessary information from the received signal, and capturing and tracking the target, particularly a monopulse radar device. It is about.

[0002]

[Prior Art]

 FIG. 3 is a block diagram of a conventional monopulse receiver. In the figure, 1 is a monopulse antenna, 2 is a mixer preamplifier for sum signals, 3 and 4 are mixer preamps for difference signals, 5 is an AGC amplifier for sum signals, and 6 Reference numerals 7 and 7 are difference signal AGC amplifiers, reference numeral 8 is a sum signal detection circuit, and reference numeral 9 is an AGC circuit for applying AGC voltage to 5 and 6 and 7.

As described above, the conventional monopulse receiver detects the AGC amplifier output signal for the 5 sum signal by the 8 sum signal detection circuit and keeps the output level constant so that the 9 sum signal AGC circuit has the AGC voltage. Is output to the AGC amplifier for 5 sum signal. The voltage was also output to the AGC amplifier for 6 and 7 difference signals to match the gains of the sum and difference signals.

[0004]

[Problems to be solved by the device]

 In the conventional monopulse receiver, the AGC voltage is controlled so that the output is constant with respect to the input of the 5 sum signal AGC amplifier, and the AGC voltage is also output to the 6 and 7 difference signal AGC amplifiers. The gains of the mixer preamplifiers 3 and 4 are not constant due to variations in frequency characteristics. Therefore, the mixer preamplifiers 2, 3, and 4 are adjusted and used as a matched pair so that almost the same gain can be obtained at each frequency.

This invention eliminates the gain difference between signal systems over a wide band by inputting a reference signal to each signal system, forming a feedback loop that detects the gain difference of each signal system and adds it to the AGC voltage. The purpose is to

[0006]

[Means for Solving the Problems]

 The monopulse receiver according to the present invention comprises a conventional circuit including an oscillator, an AGC attenuator, a gate generator, a gate circuit, a detection circuit and an AGC circuit, and a feedback loop for correcting the gain difference of each signal system over a wide band. Is added.

[0007]

[Action]

 In the present invention, a reference signal is applied to each signal system to detect a gain difference between the signal systems, and a voltage corresponding to the gain difference is added to the AGC voltage to eliminate the gain difference between the signal systems.

[0008]

【Example】

 Example 1. FIG. 1 is a diagram showing an embodiment of the present invention, and 1 to 9 are exactly the same as the above-mentioned conventional device. Reference numerals 10 and 12 are detection circuits for difference signals, which are the same as 8. Reference numerals 11 and 13 are AGC circuits for the difference signal, and compare the detection output of the reference signal output from the detection circuit for the 8 sum signal with the detection output of the reference signal output from the detection circuit for the 10 and 12 difference signals. The difference is output as an AGC voltage, the AGC voltage of the AGC circuit output for the 9 sum signal is added, and the result is given to the 6 and 7 difference signal amplifier. The gain is controlled to be the same as the gain. Reference numeral 14 is an oscillator for generating a reference signal, and its output enters a 15AGC attenuator. The AGC attenuator has the inverse characteristics of the AGC amplifier for 5 sum signals and the AGC voltage vs. gain, and the output is adjusted to be at almost the same level as the radar signal currently input to the AGC amplifier for 5 sum signals. By doing so, a stable loop gain is secured in a wide band. The 16-gate generator makes a timing for inputting the reference signal to the 2, 3, and 4 mixer preamplifiers, and its gate output is given to the AGC circuit for 11 and 13 difference signals and the 17-gate circuit. It outputs the reference signal that has almost the same output level as the radar signal at the permitted timing. The output of the mixer is input to each mixer preamplifier by the adders 18, 19, 20. Reference numerals 21 and 22 are AGC voltage adders. Figure 2 shows the timing of the radar signal and the reference signal. The reference signal is input to each mixer preamplifier using the range not used for the radar signal in one cycle of the radar, and the detection output is gated. The output of the generator compares the output of the sum signal and the output of the difference signal.

[0009]

[Effect of the device]

 As described above, according to the present invention, the feedback loop of the difference signal by the reference signal allows the gain between the signals to be substantially the same over a wide band, and the performance as a monopulse receiver can be improved. Furthermore, it is not necessary to adjust each signal system as a matched pair.

[Brief description of drawings]

FIG. 1 is a diagram showing a monopulse radar device of the present invention.

FIG. 2 is a diagram showing the timing of the monopulse radar device of the present invention.

FIG. 3 is a diagram showing a conventional monopulse radar device.

[Description of symbols] 1 monopulse antenna 2 sum signal mixer preamplifier 3 difference signal mixer preamplifier 4 difference signal mixer preamplifier 5 sum signal AGC amplifier 6 difference signal AGC amplifier 7 difference signal AGC amplifier 8 sum signal detection circuit 9 AGC circuit for sum signal 10 Detection circuit for difference signal 11 AGC circuit for difference signal 12 Detection circuit for difference signal 13 AGC circuit for difference signal 14 Oscillator 15 AGC attenuator 16 Gate generator 17 Gate circuits 18 to 20 Adder 21, 22 AGC voltage adder

Claims (1)

Claims for utility model registration: 1. An oscillator for generating a reference signal, an AGC attenuator for controlling the output level of the oscillator, and a gate for producing a timing by outputting a reference signal adjusted by the AGC attenuator. A generator, a gate circuit that outputs a reference signal according to the timing signal of the gate generator, a plurality of adders that add the signals output from the gate circuit to each signal system, and a plurality of mixer preamplifiers that receive the signals, A plurality of AGC amplifiers for amplifying the outputs, a plurality of detection circuits for detecting signals for controlling the gain of the AGC amplifiers, an AGC circuit for receiving the signals output from the detection circuits, a sum AGC circuit output and a difference AGC A monopulse radar device including an AGC adder that adds circuit outputs.