JPS6228430B2 - - Google Patents

Description

[Detailed Description of the Invention] This invention is an object of the present invention to check whether or not the function of a transponder device, which was developed for a radar device using microwave pulse radio waves, is normal by a simple operation. This invention relates to an effective transponder inspection device.

In order to help understand the significance of this invention, the above-mentioned radar device and transponder device will be briefly explained. In general, radar equipment has traditionally been used as an effective means to measure the distance and direction of distant targets, obstacles, and terrain that cannot be seen by the naked eye, day or night. It is already common knowledge.

Initially, it was used for military purposes such as early detection of enemy aircraft and shooting aiming, but it is now used for a wide variety of purposes, including auxiliary navigational instruments for ships, weather observation, air traffic control, etc. Its uses are extremely numerous.

However, when radar devices are used in a very general manner, it is often difficult to obtain a unique discrimination between echoes returned from each reflecting object. For example, when at sea, it is difficult to distinguish between merchant ships, tankers, fishing boats, warships, etc., and when in the air, it is difficult to distinguish between aircraft of unknown nationality or what model.

In order to eliminate these drawbacks, radar equipment receives pulse radio waves emitted from radar equipment (or an interrogator that emits interrogation pulse radio waves synchronized with these pulse radio waves) and has a unique identification code synchronized with these pulse radio waves. There is a transponder device that generates radio waves.

This is attached to each target object, and means is provided on the radar device side to assign a unique identification code to the echo of the equipped object.

Although it has already been put into practical use in air traffic control systems, it has not been widely used in maritime traffic control.

At sea, unlike in aircraft,
This is due to the fact that there are so many types and sizes of target objects that it is impossible to limit them, but the presence of transponder devices for navigation aids targeting radar devices as auxiliary navigational instruments for ships, which are already in widespread use, and life rafts in case of distress. Transponder devices that use the same frequency as the radar device, such as life-saving transponder devices for early detection, are about to be put into practical use as an overall economical means.

As can be seen from the relationship described above, the function of the transponder device is to react in synchronization with the pulse radio waves of its own radar device. If a simulation equivalent to pulse radio waves is required and a mock inspection is to be performed, it is usually configured by connecting a microwave pulse signal generator, a frequency measurement device, a microwave detection device, a pulse waveform observation device, etc. The need arose.

These measuring instruments are generally expensive and large in size, and if there are a large number of objects to be inspected or inspections are to be made frequently, it becomes difficult to manage all of them.

Furthermore, depending on the location where the inspection is being carried out, even the power necessary for the above-mentioned measuring instruments may not be supplied.

The present invention aims to provide a transponder inspection device that has an extremely economical and rational function for inspecting these transponder devices.

Hereinafter, FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a waveform diagram of each part, and FIG. 3 is an external view showing an example of the shape of the blocks shown in FIG. This will be explained in detail with reference to the drawings.

Note that the same symbols and numbers shown in FIGS. 1 to 3 indicate the same or corresponding parts.

In FIG. 1, reference numeral 1 denotes a pulse generator that generates a system pulse signal, and the parameters similar to those of a radar device, such as pulse width and repetition frequency, can be controlled by knobs 2 and 3. be. It also includes a run-around prevention pulse generation circuit for preventing its own run-around, which will be described later.

4 is a microwave direct oscillator 5 equipped with a Gunn diode for microwave oscillation and a variable capacitance diode for varying the oscillation frequency inside the oscillation cavity.
This is a pulse switch circuit created to control pulses, and uses high-speed switching transistors. 6 is a voltage variable circuit that controls the oscillation frequency of the microwave direct oscillator 5 by changing the voltage applied to the variable capacitance diode, and also includes a temperature compensation circuit to prevent the oscillation frequency from changing due to temperature changes. Equipped with 7 is an oscillation frequency control knob. Reference numeral 8 denotes an isolator, which is inserted so that even if the impedance of the transmitting antenna 9 changes due to external influences, the change in the oscillation frequency of the microwave direct oscillator 5 is reduced.
Reference numeral 10 denotes a receiving antenna having almost the same directivity as the transmitting antenna 9, and an electromagnetic horn type is generally suitable. In particular, the transmitting antenna 9 and the receiving antenna 10 are arranged so that they are adjacent to each other and their directional directions are parallel to each other. Reference numeral 11 denotes a variable cavity frequency meter, which acts to absorb a portion of the microwave reception power directly transmitted to the detector 13 at a resonant frequency. Note that 12 is a frequency variable knob of the variable cavity frequency meter 11. 1
Reference numeral 4 denotes a video amplifier, which has an appropriate gain for operating the subsequent system and is of a linear amplification type. 15 is a loop prevention circuit, for example, 2 inputs
A NAND gate circuit is suitable. Reference numeral 16 is an inspection mode changeover switch, which always sets one of the inputs to the two-input NAND gate circuit to logic "1" during self-inspection, and sets the above input to the pulse generator when inspecting the target transponder device. 1 is switched to the run-around inhibiting pulse b supplied from 1.
17 is a monostable multivibrator that is activated by the leading edge of the output pulse of the anti-circuit circuit 15, and its pulse width is an appropriate value within the range of 0.5 to 0.7 of the pulse interval determined from the repetition frequency of the pulse generator 1. selected for the value. 18 is a low frequency amplifier, 19 is a loudspeaker, and 20 is a battery, and generally a dry battery is suitable. Reference numeral 21 denotes a voltage stabilizing circuit, and 22 a power switch, which has all functions for operating and stopping the apparatus, and a push button switch as shown in FIG. 3 is useful. 23 is a trigger sweep type small oscilloscope with a built-in battery power supply.

Next, the functions of the entire apparatus will be explained with reference to the waveform diagram in FIG. In the waveform diagram of FIG. 2, waveforms e to h represent the case where the response pulse code from the target transponder device is Morse code "B" (-...). It goes without saying that this will change if the response pulse code of the transponder device is different. First, we will discuss the case of self-inspection. In FIG. 1, the inspection mode changeover switch 16 is switched to the T side, and the power switch 2 is turned on.
2, the whole circuit is supplied with power, and at the same time a microwave pulse signal having a certain value according to the system pulse a generated by the pulse generator 1 is generated.
It is radiated from the transmitting antenna 9. This microwave pulse signal is also input to the receiving antenna 10 arranged adjacently and in parallel, and the video amplifier 14
The self-transmitted pulse detection waveforms appear on the output g of . Also, at this time, since one input to the loop suppression circuit 15 is given as logic "1" as described above, the monostable multivibrator is excited by its own transmission pulse appearing at the output g, and the loudspeaker From 19, a sound with a pulse repetition frequency is obtained, indicating that the own loop test is functioning. When the inspection mode changeover switch 16 is switched to the N side, the sound is stopped because the switch is switched to the roundabout suppression pulse b. The pulse width of the bypass suppression pulse b is suitably equal to or slightly wider than the pulse width of the system pulse a. For details on transmit pulse specifications,
While observing the pulse waveform of the output g with the oscilloscope 23, the transmission frequency can be read from the dial scale of the variable cavity frequency meter 11 by operating the knob 12 to lower the amplitude of the output g. Of course, in order to obtain the desired oscillation frequency, the dial of the variable cavity frequency meter 11 may be set to a predetermined scale, and the knob 7 may be varied to obtain the desired oscillation frequency. Similarly, the pulse width and repetition frequency can be selected using knobs 2 and 3 while observing the output g.

It goes without saying here that the operations of the knobs 2, 3, and 7 can be facilitated by attaching respective calibration scales to the target surfaces of the knobs 2, 3, and 7 in advance.
Next, the case of inspecting the target transponder device will be described. While the inspection mode changeover switch 16 is switched to the N side, the transmitting antenna 9 and the receiving antenna 10 are radiated with the same directivity and polarization plane toward the target transponder device. When the transponder device responds, the loudspeaker 19 generates sound, and at the same time, the oscilloscope 23 allows the detection of the response wave to be observed. Not only can the response code pulse train be confirmed from this detected waveform, but also the response code pulse train can be confirmed using the knob 12.
The frequency of the response wave can also be measured in the same manner as described above. In addition, if you understand the performance of this device, it is possible to make a response from the target transponder device based on the amplitude of the response wave appearing in the output g and the distance between them, which indicates the effective radiated power of the target transponder device and the distance that indicates the response limit. You can also check the received power level.

The function as a transponder inspection device has been described above, but the transmission system part of the present invention can be used as a simple microwave pulse signal test oscillator for the purpose of investigating the spurious sensitivity of the receiving system of a radar device.
It is clear that the receiving system part can be used independently for searching for microwave noise sources.

As described above, the transponder inspection device according to the present invention is capable of comprehensively and quickly inspecting the target transponder device using space without connecting any measuring equipment, and also checks whether or not there is a commercial power supply. It has the advantage of requiring no preparation.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention;
Fig. 2 is a waveform diagram of the main parts of each block shown in Fig. 1, and in particular e to h show the case where the response pulse code from the target transponder device is Morse code "B". FIG.
FIG. 3 is an external view showing an example of the blocks shown in FIG. 1, which are expressed using trigonometry. In the figure, 1 is a pulse generator, 2, 3, 7, and 12 are knobs, 4 is a pulse switch circuit, 5 is a microwave direct oscillator, 6 is a voltage variable circuit, 8 is an isolator, 9 and 10 are transmission and reception, respectively. antenna for
11 is a variable cavity frequency meter, 13 is a direct detector,
14 is a video amplifier, 15 is a loop suppression circuit, 16
17 is a monostable multivibrator, 18 is a low frequency amplifier, 19 is a loudspeaker, 20 is a battery 21 is a voltage stabilization circuit,
22 is a power switch, and 23 is a small trigger sweep type oscilloscope with a built-in battery power source.
In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. A pulse generator that generates a loop prevention pulse signal to prevent a system pulse signal or a transmission signal from looping around to a receiving system, and the specifications of the pulse signal generated from the pulse generator. a microwave oscillator driven by the system pulse and outputting a microwave pulse of a predetermined frequency; an oscillation frequency adjustment means for adjusting the oscillation frequency of the microwave oscillator; a transmitting section having a transmitting antenna that radiates microwave pulses into space; and a transmitting section that is provided adjacent to the transmitting antenna, and a response wave from a target transponder device that reacts with the microwave pulse and from the transmitting antenna. a receiving antenna that receives the wraparound microwave pulse; a variable cavity frequency meter that absorbs and outputs a portion of the microwave received power from the receiving antenna at its resonant frequency; and a variable cavity frequency meter that adjusts the resonant frequency of the frequency meter. a detector for detecting the output of the variable cavity frequency meter; and a video amplifier for amplifying the output of the detector with a predetermined gain;
Received wave specification observation means for observing the pulse waveform and frequency of the received wave, consisting of an oscilloscope that receives the output of the video amplifier and displays the output waveform; An inspection mode changeover switch for switching to either of the two modes; a circuit for passing the received detection output of the microwave transmission pulse that has entered the receiving system in the self-inspection mode, and removing the reception detection output of the microwave transmission pulse when inspecting the transponder; a pulse-response wave receiving section comprising a noise generation means that receives the output of the interference prevention circuit and generates a sound corresponding to the received wave; and a pulse response wave reception section for driving the transmission section and the pulse response wave reception section. A transponder inspection device comprising: a battery power source, wherein the transmitting section, the receiving section, and the battery power source are built into the same housing.