JP3125498B2 - Radar beacon device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a radar beacon device which outputs a beacon signal having the same frequency as a received radar signal.

FIG. 3 shows an example of a PPI (plane pos).
FIG. 3 is a diagram showing a radar beacon signal on an ion indicator. The radar beacon device emits an encoded radio wave in response to the radio wave emitted from the ship's radar as soon as it is received. FIG. 3 shows the returned beacon signal on the radar PPI of the ship. As shown, a signal appears outward from the place where the radar beacon device is installed in the radial direction of the PPI so that the installation position of the device can be easily determined.

[0003]

2. Description of the Related Art FIG. 4 is a block diagram of a main part of a conventional radar beacon device. In FIG. 4, when a radar signal pulse is received by the receiving unit 8, the signal is input to the frequency discriminator 2 to discriminate the frequency, converted to a digital signal by the A / D converter 10, and input to the data holding circuit 20. The D / A converter 14 converts the value of the frequency converted into a digital signal into an analog voltage, and supplies the analog voltage to the voltage control oscillator 4 to receive the signal corresponding to the voltage. A signal having substantially the same frequency as the frequency of the radar signal is oscillated, modulated by the modulation unit 5 with the coded signal, and transmitted from the transmission unit 9.

In this case, after the frequency data is held in the data holding circuit 20, about 17 ms of the main rope signal receiving time which is a time sufficient for detecting the position of the radar beacon device on the PPI on the ship side. And the control unit 21
Resets the data holding circuit 20 to stop the oscillation of the voltage controlled oscillator 4.

[0005]

However, A / D
The accuracy of the conversion unit 10 and the D / A conversion unit 14;
There is a problem in that the frequency of the beacon signal output from the voltage controlled oscillator 4 deviates from the frequency of the radar signal due to changes in environmental conditions such as temperature and power supply voltage.

An object of the present invention is to provide a radar beacon device in which the frequency of a beacon signal does not deviate from the frequency of a radar signal even when the accuracy of the circuit is loose and environmental conditions such as temperature and power supply voltage change. .

[0007]

SUMMARY OF THE INVENTION The frequency of a received radar signal
Wave number information is obtained using a frequency discriminator, and the received
Voltage control to output a signal with the same frequency as the
Applying a control voltage to the oscillator, and an output signal of the voltage controlled oscillator
A beacon signal is generated using
In Dabikon device, received from said frequency discriminator
Storage means for storing frequency information of the received radar signal;
A voltage corresponding to the frequency information stored in the storage means;
A first control voltage generator to provide a serial voltage controlled oscillator, before
Voltage corresponding to the frequency information stored in the storage means
The output signal from the voltage controlled oscillator
And switching means provided to the frequency discriminator in place, the
The frequency information stored in the storage means corresponds to the output signal.
The difference from the frequency information from the frequency discriminator
The voltage corresponding to the frequency information obtained by adding the frequency information is described above.
A second control voltage generator to provide a voltage controlled oscillator, wherein
When detecting that the difference has become 0, the output signal is transmitted to the transmitting unit.
And before detecting that the difference has become zero,
Is a control for controlling not to give the output signal to the transmitting unit.
Means.

[0008]

According to the present invention, the storage means stores the received laser from the frequency discriminator.
A first control voltage generator for storing frequency information of the
Controlling the voltage corresponding to the stored frequency information
Give to the oscillator. Then, the voltage control is performed by the switching means.
The output signal from the oscillator is replaced with the radar signal and the
Give to wave number discriminator.

On the other hand, in the second control voltage generation unit, the storage
Means corresponding to the frequency information stored in the means and the output signal.
The difference between the frequency information from the wave number discriminator and the stored frequency
A voltage corresponding to the frequency information obtained by adding the number information to the voltage
Give to control oscillator. And the output from the voltage controlled oscillator
A force signal to the frequency discriminator by the switching means.
Operation by the so-called feedback loop
Repeat until the difference becomes zero.

The control means detects that the difference has become zero.
Control to give the output signal to the
You. Before detecting that the difference has become 0,
The output signal is controlled so as not to be supplied to the transmission unit. Departure
According to the description, between the received radar signal and the signal to be transmitted
Does not transmit when there is a frequency difference between
The transmission can only be started when it is gone.

As a result, the accuracy of the circuit and the temperature
Changes in environmental conditions such as power supply voltage and
The output frequency of the radar is different from the frequency of the radar signal.
The output frequency of the voltage-controlled oscillator is also
And then output as a beacon signal,
Beacon signal frequency deviates from radar signal frequency
Disappears.

[0012]

FIG . 1 is a block diagram showing the principle of the present invention. FIG.
As shown in the figure, usually connected to the radar signal input side,
Switch to the second changeover switch 6 side by a signal and input
Radar signal or a signal from the second changeover switch 6
Is input to the frequency discriminator 2 which discriminates and outputs the frequency.
The first changeover switch 1 to be activated and the output of the frequency discriminator 2
And memorize the frequency of the input radar signal.
Output the voltage corresponding to
The second switching switch based on the frequency of the radar signal.
Difference obtained by subtracting the frequency of the output of the modulation unit 5 via the switch 6
A voltage corresponding to the added value is output, and the difference becomes zero.
Radar signal frequency storage, radar frequency
Addition and difference 0 detection unit 3 and the radar signal frequency
Number storage, difference addition with radar frequency, and difference 0 detection unit 3
And output a signal of a frequency corresponding to the input voltage.
The voltage controlled oscillator 4 for oscillating, and the voltage controlled oscillator 4
A modulating unit 5 modulates the output of at coded signal, usually the
The output of the modulator 5 is connected to the first switch 1 side,
The second switching to the beacon signal output side by the control signal
Switch 6 and the radar signal frequency storage and radar
The difference addition with the frequency and the difference 0 detection unit 3 input the difference.
The frequency of the radar signal is stored and a voltage corresponding to this is output.
When the first switch 1 is turned on,
To the second changeover switch 6 side, and
When the difference 0 is detected, the second switching switch is activated by the control signal.
Switch 6 to beacon signal output side for a predetermined time
When returning to the original position, the first changeover switch 1 is set to a radar signal input.
And a control unit 7 for switching to side connection. Book
According to the invention, the frequency of the input radar signal is determined by the frequency valve.
The data of the frequency discriminated by the discriminator 2 is
Radar signal frequency storage, difference addition and difference with radar frequency
Stored in the minute 0 detection unit 3 and corresponding to the stored frequency.
When the pressure is output, the control unit 7 controls the first changeover switch 1
Are connected to the second changeover switch 6 side. Voltage control
The oscillating unit 4 outputs a signal having a frequency corresponding to the output voltage.
Input to the modulator 5 and modulates the signal modulated by the coded signal.
Input to the frequency discriminator 2 and the data of the discriminated frequency
Is stored in the radar signal frequency, and the difference with the radar frequency is added.
And input to the difference 0 detection unit 3,
The frequency of the radar signal is modulated by the frequency of the radar signal.
The difference obtained by subtracting the frequency of the voltage controlled oscillator 4 from the output of the unit 5 is
A voltage corresponding to the added value is output, and the voltage control oscillator
4 and oscillate a signal with a frequency corresponding to this voltage,
The signal is input to the modulation unit 5 and modulated by the coded signal.
Input to the number discriminator 2 and the data of the discriminated frequency is
Radar signal frequency storage, difference addition with radar frequency and
The input to the difference 0 detection unit 3 is performed by the voltage control oscillation unit 4.
Until the difference between the frequency of the radar signal and the frequency of the radar signal becomes zero.
Return. When the difference becomes 0, the control unit 7 responds to the control signal.
Return the contact of the first change-over switch 1
Between the contacts of the second changeover switch 6 to the beacon signal output side
Connected voltage controlled oscillator that matches the frequency of the radar signal
4 is modulated by the modulation unit 5 with the encoded signal.
Output the beacon signal as a beacon signal.
The contacts of the changeover switches 1 and 6 are returned to their original positions. That is, the accuracy of the circuit
Changes in environmental conditions such as temperature and power supply voltage.
The output frequency of the voltage control oscillator 4 is the frequency of the radar signal.
The output frequency of the voltage controlled oscillator 4
Match the frequency of the
Output as a beacon signal.
The frequency will not deviate from the frequency of the radar signal. FIG. 2 is a block diagram of a main part of the radar beacon device according to the embodiment of the present invention. In FIG. 2, the radar signal pulse input from the receiving unit 8 is input to the frequency discriminator 2 via the changeover switch 1,
The discriminated frequency is input to the A / D converter 10 of the radar signal frequency storage, the difference addition with the radar frequency, and the difference 0 detection unit 3, converted into a digital signal, and received via the changeover switch 11. 12 and hold the frequency value. Note that the reception signal holding circuit 12 corresponds to the storage means.
Respond.

The frequency value held by the reception signal holding circuit 12 is sent to and held by the data holding circuit 13 and is input to the D / A converter 14 to be converted into a voltage value of an analog signal, which is input to the voltage controlled oscillator 4. A signal having a frequency corresponding to the voltage is oscillated, input to the modulator 5, and modulated by the coded signal. The data holding circuit 13 and the D / A converter 14
Corresponds to a first control voltage generator.

When the frequency value is held in the reception signal holding circuit 12 and the voltage value of the analog signal is input to the voltage control oscillating unit 4, the control unit 7 detects this and sends a control signal, and the changeover switch 1 and the changeover switch 11 is the dotted line side.

Then, the signal modulated by the coded signal in the modulator 5 is input to the frequency discriminator 2 via the changeover switch 6 and the changeover switch 1, and the signal of the discriminated frequency is A / D The signal is converted into a digital signal by the converter 10, input to the comparison circuit 15, and a difference between the digital signal and the frequency value of the radar signal held by the reception signal holding circuit 12 is obtained. In addition,
The combination of the changeover switch 6 and the changeover switch 1 is turned off.
Corresponds to replacement means.

Although it is desirable that the difference is 0 in the comparison circuit 15, the accuracy of the D / A converter 14 is not sufficient (the A / D converter 10 also passes the radar signal and the output of the voltage controlled oscillator 4). Therefore, the accuracy of the A / D conversion unit 10 does not matter, and a difference occurs due to a change in the frequency of the voltage control oscillation unit 4 due to a change in environmental conditions such as temperature and power supply voltage.

The comparison circuit 15 subtracts the value of the frequency of the voltage controlled oscillator 4 from the value of the frequency of the radar signal held in the reception signal holding circuit 12 and adds the difference to the addition circuit 16.
Is added to the value of the frequency of the radar signal stored in the data holding circuit 13, and the added value is stored in the data holding circuit 13 again, input to the D / A conversion unit 14, and added to the added value. A voltage control oscillator 4 for outputting a corresponding analog voltage
Give to. The comparison circuit 15, the addition circuit 16, the data
The holding circuit 13 and the D / A conversion unit 14
It corresponds to a pressure generating unit.

Then, the output signal of the voltage controlled oscillator 4 is input to the modulator 5 and is modulated by the coded signal. The output signal is input to the frequency discriminator 2 via the changeover switch 6 and the changeover switch 1 to determine the discriminated frequency. Is converted into a digital signal by the A / D converter 10, input to the comparison circuit 15, and a difference from the frequency value of the radar signal held by the reception signal holding circuit 12 is obtained. The value is added to the stored frequency value, and the added value is again stored in the data holding circuit 13.
Is input to the D / A conversion unit 14, and an analog voltage corresponding to the added value is output and given to the voltage control oscillation unit 4 until the comparison circuit 15 determines that the difference is 0.

When the comparison circuit 15 determines that the difference is 0, the control unit 7 issues a control signal, sets the changeover switch 11 to the original solid line side, and sets the changeover switch 6 to the radar beacon device on the ship-side PPI. Approximately 17 ms of the reception time of the main rope signal sufficient to detect the position of
Transmitter 9 transmits a beacon signal that matches the frequency of the radar signal.
And the changeover switches 1 and 6 are connected to the original solid line side. Note that the control unit 7 corresponds to control means.

That is, even if the output frequency of the voltage controlled oscillator 4 is different from the frequency of the radar signal due to the accuracy of the circuit and changes in environmental conditions such as temperature and power supply voltage, the output of the voltage controlled oscillator 4 Since the frequency is matched with the frequency of the radar signal and then output as a beacon signal for a predetermined time, the frequency of the beacon signal does not deviate from the frequency of the radar signal.

[0021]

As described above in detail, according to the present invention, the frequency of the beacon signal deviates from the frequency of the radar signal even if the accuracy of the circuit is unsatisfactory and environmental conditions such as temperature and power supply voltage change. There is an effect that no radar beacon device can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the principle of the present invention;

FIG. 2 is a block diagram of a main part of a radar beacon device according to an embodiment of the present invention;

FIG. 3 is a diagram illustrating a radar beacon signal on an example PPI;

FIG. 4 is a block diagram of a main part of a conventional radar beacon device.

[Explanation of symbols]

1, 6 and 11 are changeover switches, 2 is a frequency discriminator, 3 is a radar signal frequency storage, a difference addition and a difference 0 detection unit with the radar frequency, 4 is a voltage controlled oscillation unit, 5 is a modulation unit, and 7 and 21 are Control unit, 8 is a receiving unit, 9 is a transmitting unit, 10 is an A / D converter, 12 is a received signal holding circuit, 13 and 20 are data holding circuits, 14 is a D / A converting unit, 15 is a comparing circuit, 16 Indicates an adder circuit.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Masaru Aizawa 1-2-2, Ichibancho, Aoba-ku, Sendai City, Miyagi Prefecture Fujitsu Tohoku Digital Technology Co., Ltd. (56) References JP-A-56-106171 (JP) JP-A-4-305182 (JP, A) JP-A-4-262285 (JP, A) JP-A-2-269543 (JP, A) JP-A-58-115380 (JP, A) JP-A-4-315979 (JP, A) JP-A-2-19784 (JP, A) JP-A-4-361188 (JP, A) JP-A-1-197683 (JP, A) JP-A-60-14186 (JP, A A) JP-A-4-203996 (JP, A) JP-A-63-35975 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01S 13/74-13/84

Claims (1)

(57) [Claims] 1. The method according to claim 1, wherein the frequency information of the received radar signal is
The same as the radar signal obtained and acquired using a number discriminator
Control voltage to the voltage-controlled oscillator to output a frequency signal.
Voltage, and the beacon is output using the output signal of the voltage controlled oscillator.
Radar beacon device that generates a
In location, frequency information of the received radar signal from said frequency discriminator
And a voltage corresponding to the frequency information stored in the storage means.
A first control voltage generator to be applied to the voltage controlled oscillator, and a voltage corresponding to the frequency information stored in the storage means.
The output signal obtained from the voltage controlled oscillator is
Switching means for giving to the frequency discriminator in place of the signal, and a pair of frequency information and the output signal stored in the storage means.
The difference from the frequency information from the corresponding frequency discriminator is stored in the memory.
Voltage corresponding to the frequency information obtained by adding the
A second control voltage generator for supplying the voltage-controlled oscillator with the output signal when the difference is detected to be 0;
Before detecting that the difference has become zero.
Control so that the output signal is not supplied to the transmission unit.
Radar beacon apparatus characterized by comprising: a control means.