JPS586481A - Beacon transmitter - Google Patents

Abstract

PURPOSE:To obtain a beacon transmitter of a small size which has a small number of circuits, by switching the output frequency of an oscillator with every pulse or every pulse group and carrying out the sweeping of plural frequencies. CONSTITUTION:The output frequency of an oscillator is switched with every pulse or every pulse group to perform the sweeping of plural frequencies. For instance, a pulse generating circuit 10 produces a rectangular pulse train, and a voltage control oscillator 11 produces a sweep frequency according to the rectangular pulse train. A sweep generating circuit 13 produces two types of sweep waveforms, and a sweep switching circuit 12 switches and delivers the two types of sweep waveforms with every pulse and after receiving these two types of sweep waveforms and the pulse train given from the circuit 10. The output of the circuit 12 is applied to the oscillator 11. The oscillating output of the oscillator 11 is amplified by an electric amplifier 14 and radiated into air through an antenna 15.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a peakon transmitting device for a radar that constantly emits pulsed radio waves, displays a bright line on the image display screen of the radar that receives the radio waves, and informs the radar of the installation direction of the device. It is something.

In such a beacon transmitting device, when there are a large number of target radars, it is common to sweep the transmission frequency within a necessary range in order to cover the frequency range of the radars. In order to increase the reception rate of beacon radio waves on the radar side, a method is used to add radio waves that perform another frequency sweep.

Figure 1 shows an example of the frequency sweep method in such a case, and (A) divides the required frequency range into high and low parts and calculates
In (B), the two frequency sweeps fA and fB, which sweep the required frequency range, are temporally shifted by a half period. The Raymark/Pecon transmitter used in Japan is 9340-9.
A three-sweep method similar to the method shown in FIG. 1(A) and the method shown in FIG. 1(B) is used for 470 hours.

Conventionally, when performing such multiple frequency sweeps, multiple oscillators were used. FIG. 2 shows a conventional embodiment that performs a two-frequency sweep. 13 and 1b in the same figure are pulse generation circuits for the high-frequency sweep system and low-frequency sweep system, respectively (hereinafter a corresponds to the high-frequency sweep system and b corresponds to the low-frequency sweep system), and 2a and 21) are electrical and pressure controlled oscillators. , 3a and 31) are power amplifiers, 4a and 4
b is a sweep generation circuit, 5 is a synchronization signal generation circuit, 6 is a hybrid circuit, and 7 is an antenna. In this embodiment, two oscillators are used to perform two frequency sweeps.

The present invention aims to improve the conventional device that uses multiple oscillators to perform multiple frequency sweeps as described above, and focuses on the fact that the transmitted radio waves are pulses. It is characterized in that the frequency is switched for each pulse or for each group of pulses to perform a plurality of frequency sweeps. A detailed explanation will be given below based on examples.

FIG. 3 shows a block diagram of an embodiment of the invention.

10 in the figure is a pulse generation circuit that generates a rectangular pulse train. Reference numeral 11 denotes a voltage controlled oscillator which receives a rectangular pulse train from the pulse generating circuit 10 and oscillates with amplitude modulation according to this pulse train.This oscillator 11 also receives a voltage waveform from the sweep switching circuit 12 and oscillates according to the voltage waveform. It oscillates at a frequency of m height. 13 is a sweep generation circuit that generates two types of sweep waveforms.

12 is a sweep switching circuit which receives two types of sweep waveforms from the sweep generation circuit 13 and the 012 column from the pulse generation circuit IO;
The two types of sweep waveforms mentioned above are switched and output for each pulse. The output voltage waveform of switching circuit 12 is applied to voltage controlled oscillator path 11. 14 is a power intensifier which receives the oscillation output from the voltage controlled oscillator 11 and amplifies the power thereof. An antenna 15 receives the amplified output from the power amplifier 14 and emits it into the air.

FIG. 4 shows the waveforms of each part in FIG. 3, where (al) is the output waveform of the ζ pulse generation circuit 10, +b) is the output waveform of the sweep switching circuit 12, and (C) is the oscillation frequency waveform of the voltage controlled oscillator. , fA and vA correspond to each other, and fs and VB correspond to each other.

As explained above, in the above embodiment, with one oscillator,
Two different frequency sweeps are performed for each pulse. Therefore, compared to the conventional case where two oscillators are used, the number of oscillators and their related circuits is reduced, and the device becomes simpler.

As described above, according to the present invention, it is possible to sweep a plurality of frequencies with one oscillator, and the device has the advantage of being simple, compact, and inexpensive, and is extremely effective when used in a peak transmitter.

[Brief explanation of drawings]

Figures 1 (A) and (13) are waveform diagrams of frequency sweep;
The figure is a block diagram of a conventional embodiment. Figure 3 is a block diagram of an embodiment of the present invention, and Figures 4 (al to C1 are waveform diagrams of each part in Figure 3. 10 is a pulse generation circuit, 11 is a voltage controlled oscillator, and 12 is a sweep switching circuit. , 13 is a sweep generation circuit, 14 is a power amplifier, and 15 is an antenna. Patent applicant: Oki Electric Industry Co., Ltd. Patent agent Megumi Yamamoto -

Claims (1)

[Claims] A beacon transmitting device that emits pulsed radio waves and informs the radar of the installation direction of the device using a bright line displayed on the radar's image display screen includes a single pulse generating circuit and a sweep generator that generates at least two types of sweep waveforms. a sweep switching circuit that switches the sweep waveform according to the output of the pulse generation circuit, a voltage controlled oscillator that generates a sweep frequency according to the output of the sweep switching circuit and the output of the pulse generation circuit, and amplifying the output of the oscillator. What is claimed is: 1. A beacon transmitting device characterized by having a means for transmitting a beacon into the air.