JPS586155B2 - radio wave response device - Google Patents

Description

[Detailed Description of the Invention] This invention normally repeats transmission and pausing at a fixed rate, and when radar radio waves are detected, the transmission and pausing operations are stopped and transmission is performed in accordance with the radar radio waves. Regarding a radio wave response device.

In order to carry out rescue operations efficiently and quickly in times of distress, when a victim is irradiated with radar radio waves from a search boat, a sweep is carried out that sweeps a fixed frequency range that includes the frequency of the radar radio waves for a short fixed period of time. There is a rescue system that carries a radar radio response device that transmits response radio waves and receives them on the radar side to determine the location of the victim, but the radar radio response device used in this rescue system is If the radar radio waves are not detected, the radio signal will not be transmitted, so for example, the route for sending the radar device and receiving the radar radio transponder in a rescue system consisting of the radar equipment of the search boat and the radar radio transponder carried by the victim. When the performance is lower than the performance of the radar radio wave transponder sending route and the radar equipment receiving route (for example, when the receiver is equipped with a radar device with high receiving sensitivity but low transmitting output, or when the radar radio wave transponder receiving Cases where performance has deteriorated are assumed.

) Even though it is possible to transmit signals from the radar radio response device to the radar device, the radar response device cannot detect the radar radio waves from the radar device, so the response radio waves cannot be transmitted. The problem arises that it does not work effectively.

This invention was made in view of these problems, and even if the performance of a part of the rescue system is low or degraded, it can still ensure the maximum rescue area and operate effectively as a rescue system. It was made so that it could be done.

Details will be explained below based on the drawings.

FIG. 1 shows an example of a circuit diagram of a radio wave response device according to the present invention.

1 is a receiving antenna that receives radar radio waves emitted from search ships, etc.; 2 is a receiving section that detects the radar radio waves and converts them into logic signals; 3 is an inhibit gate; and 4 is a one-shot multi section. So, OR circuit 43
5 is a part of a timer, which is applied to the reset terminal 51 via an OR circuit 53, and outputs a logic signal that continues for a certain period of time τ2 (approximately 200 μs) to the output terminal 42 in response to a start signal applied to the start terminal 41 through the OR circuit 53. When the reset signal is logic voltage "H", it is held in a stopped state, and when the reset terminal 51 becomes logic voltage "L", it starts operating and generates an output signal after a certain period of time .tau.4 (approximately 4 ms).

6 is a modulation signal generator whose period is constant time τ4 (approximately 10μ
s) that generates a sawtooth-shaped modulation signal; 7 is a sweep signal generation section that generates a response radio wave signal whose frequency is swept by the modulation signal;

In addition, the frequency range is a predetermined frequency band for radar radio waves equipped with the search vessel, etc., for example, 9,300 MHz to 9,5 MHz.
It is assumed that the sweep is performed to cover 00MHZ.

Reference numeral 8 denotes a power supply control unit, which allows the power supply 10 to supply power to the sweep signal generation unit 7 only during the period when the output signal of the one-shot multi-unit unit 4 is at the logic voltage “H”; 9, a transmitting antenna; 11 is a monitor unit that radiates the frequency-swept radio wave signal generated as shown in FIG.
It is controlled by the output signal of the one-shot multi section 4 and monitors when a radio signal is radiated in response to radar radio wave irradiation.

FIG. 2 is a reference diagram showing the time relationship of signals of each part.

Next, the operation will be explained.

First, the operation during a period when radar radio waves are not effectively detected will be explained.

Cases that correspond to this state include when a radar-equipped search vessel has not arrived in the nearby sea, or when the performance of the radar device sending and receiving radio wave response device is insufficient (if the transmission output of the radar device is low, the radio wave response device receiving In addition to cases where the sensitivity is low, this also includes cases where the reception sensitivity of the radar device is high.

) etc. In this case, since the timer section 5 is operating, it outputs an output after a certain period of time τ4 (approximately 4 ms) (see FIG. 2D) and performs self-resetting.

Therefore, an output signal is generated at the output terminal 52 every τ4.

This output signal triggers the one-shot match section 4 for a fixed period of time τ2 (approximately 200 μs) (see Fig. 2B).
A continuing signal is output to the output terminal 42.

This output signal is applied to the modulation signal generation section 6 (see FIG. 2C for the waveform of the modulation signal) and the power supply control section 8.

As a result, the sweep signal generator 7 is driven, and the antenna 9 transmits a radio wave signal swept over a predetermined frequency range at a rate of transmission for τ2 (approximately 200 μs) and pause for τ4 (approximately 4 ms).

Next, the operation during the period when radar radio waves are received and detected as valid signals will be described.

In this state, the radar radio wave is applied to the activation terminal 41 of the one-shot multi section 4 via the receiving section 2 and the inhibit gate 3.

As a result, the timer part 5 is reset and put into a non-operating state, while the one-shot multi-function part 4 is set for a certain period of time τ2.
A continuous output voltage is output to the output terminal 42 (for about 200 μs).

This signal drives the modulation signal generation section 6 and the power supply control section 8, and the sweep signal generation section 7 generates a predetermined sweeping radio wave signal, which is radiated into space.

Note that the output of the one-shot multi 4 controls the inhibit gate 3 to prevent self-run due to interference during transmission.

By the way, the radar radio waves emitted from the search ship side are, for example, τ0
(approximately 1 μs) transmission, τ3 (approximately 1 ms) pause radio signal (
(See Figure 2 A) However, due to the rotation of the antenna of the radar device, the radio wave transponder side receives and detects radar radio wave irradiation only during the period when the beam of the antenna device is facing the radio wave transponder side. In response to this, an operation is performed to transmit a radio wave signal that sweeps a predetermined frequency range.

Furthermore, as described above, when radar radio waves are not extracted by the radio wave transponder, automatic transmission is performed, so the search vessel's radar equipment has a radar antenna facing the radio wave transponder side, regardless of radar radio wave transmission. During this period, the radio wave signal emitted from the radio wave response device is received regardless of the operation timing of the radar device, so it is displayed as a single directional line on the PPI display panel of the radar device, which allows the victim to Only the direction you are in will be shown.

Next, when the radar radio wave is detected in the radio response device, a response radio signal is emitted at a fixed timing according to the radar radio wave, so the time relationship between the radar radio wave and the response radio wave signal is synchronized. The direction and distance to which the victim is located are shown on the PPI display panel of the radar device.

Also, here, the timer part 5 is reset by the output signal of the one-sit multi part 4, and the time from when this reset is released until the output signal is generated from the timer part 5 (τ4: about 4 ms) is a few minutes compared to the time that the radar antenna beam of the search vessel points toward the radio response device (for example, if the antenna beam width is 2 degrees and the rotation speed is 15 rpm, this time is about 20 ms). 1 (in this example, τ4 = 4 ms, so 1/5), so transmission is performed several times (4 to 5 times) by the operation of the timer part 5 while the radar antenna is facing the radio wave response device. It will be done.

Therefore, this signal can be extracted with sufficient brightness on the PPI display panel of the radar device of the search vessel.

Furthermore, the transmission in this case is τ2 (approximately 200 μs) transmission,
Since the pause is repeated for τ4 (approximately 4 ms), from the standpoint of signal detection in the radar device, it is detected almost the same as continuous transmission, and has the same effect, but in terms of power consumption of the radio response device, it is different from continuous transmission. The power consumption can be drastically reduced compared to the above (corresponding to 1 transmission and 8 pauses in the above example), and this eliminates the need for a large power supply unit and high cost, which are one of the constraints on the practical use of this type of radio wave response device. etc. can be improved.

As described above, the radio wave response device according to the present invention automatically transmits radio waves in a predetermined format that repeatedly sweeps the radar frequency band for ships, etc., which transmits and pauses at a predetermined rate, and when it detects the irradiation of radar radio waves. In response to this, the above-mentioned automatic transmission is stopped for a certain period of time after the radar radio wave is received, and the radio waves in the predetermined format are transmitted for a short period of time, so that the performance of the route for transmitting the radar device and receiving the radio wave response device is as low as the radio wave response device. Even if the performance of the route receiving the sending radar device is low and the radar radio waves are not detected, the direction in which the victim is located can be quickly detected.

On the other hand, when the search boat approaches the victim to some extent and the radio wave response device begins to extract radar waves, it functions as a radar wave response device and can determine the direction and distance, making rescue operations effective and quick. It has the effect that it can be used for.

[Brief explanation of the drawing]

FIG. 1 is a circuit system diagram showing an example of a radio wave response device according to the present invention, and FIG. 2 is an explanatory diagram showing the time relationship of signals of each part. 1... Receiving antenna, 2... Receiving section,
3...Inhibit circuit, 4...One-shot multi section, 5...Timer part, 6...
... Modulation signal generation section, 7 ... Sweep signal generation section, 8 ... Power supply control section, 9 ... Transmission antenna, 10 ... Battery, 11...Monitor section.

Claims (1)

[Scope of Claims] 1. A first switch circuit that generates an output signal that is held for a certain period of time in response to detecting radar radio waves. Normally, a second switch circuit operates on and off at a predetermined timing and generates an output signal based on this on/off operation, and when a radar radio wave is detected, it is reset and stops the on/off operation and the output signal disappears. , a transmitter that is controlled by output signals obtained from the first switch circuit and the second switch circuit, repeatedly sweeps from one specific frequency to another frequency at a predetermined speed, and sends out this sweep signal. A radio response device equipped with