JPH03111784A - Interrogator for identification - Google Patents

Abstract

PURPOSE:To prevent the generation of a pseud-response signal and to make it possible to display the effective response signal by making a receiving region agree with a primary radar when the repeating frequency of the primary radar is higher than the allowable maximum repeating frequency of an interrogator for identification. CONSTITUTION:When the frequencies of pulse signals T1 and T2 among the repeating frequencies of primary radar 1 exceed the allowable maximum repeating frequency of an interogating apparatus 33 for identification, a synchronizing circuit 37 thins inputted synchronizing signals (a), and a repeating frequency for interrogation is gener ated. Pulses A - C comprising mode pulses P1 and P3 are generated in a coder 39. Response signals a1-c1 and a2-c2 from an aircraft are applied into a received signal processing circuit 49 from a receiver 47. At this time, a delay circuit 57 detectes the pulse P3 and outputs a signal after the specified time. The gate of a gate generating circuit 45 is opened. Meanwhile a delay circuit 55 receives signals T1-T5. The gate of the circuit 45 is closed after the specified time. Therefore a pseud-response signal a2 is not included in the data of a radar indicator 32. Since the response signals b2 and c2 from the remote aircraft are included, the accurate indication can be performed.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to an identification interrogation device used for air traffic control and identification of aircraft or ships, and in particular to an identification interrogation device used for air traffic control and identification of aircraft or ships, and in particular, interrogation devices that can be used with one or more primary radar devices having different repetition frequencies. The present invention relates to the configuration of an identification interrogation device used in combination.

(Prior art) Radar devices that emit radio waves from an antenna and detect the location of a target by receiving reflected waves from the irradiated target have been indispensable for aircraft traffic control and ship navigation. It has become a thing.

In addition, in recent years, with the increase in the number of aircraft and ships, aircraft and ships are concentrated in airspace and sea areas where air traffic control or ship identification is required, and the burden of air traffic control or identification work has increased significantly. By combining and displaying the information obtained by the identification interrogation device, such as the aircraft identification code, altitude, or speed, on the primary radar indicating device, the information necessary for air traffic control or identification can be comprehensively obtained. A system of understanding has been adopted and developed.

FIG. 4 is a diagram showing an example of a conventional identification interrogation system used in an aircraft, in which the repetition frequency of the primary radar device is higher than the maximum repetition frequency allowed by the interrogation device. FIG. 2 is a diagram showing the configuration of the device in the case of

In the figure, 1 is a primary radar device, 2 is a radar indicator,
3 is an interrogation device, and the primary radar device 1 has a built-in repetition frequency generator 5, and the interrogation device 3 includes a synchronization circuit 7, a KOG 9, a transmitter 11, a duplexer 13, a gate generation circuit 15, Receiver 17, received signal processing circuit 19
, a switch 21, a decoder 23, and an antenna 25.

The synchronization circuit 7 inputs the synchronization signal from the repetition frequency generation circuit 5 built into the primary radar device, and divides or thins out the synchronization signal so that the repetition frequency is within the maximum repetition frequency allowed by the interrogation device 3. Generates the repetition frequency of the interrogation device and outputs it to Cog 9. The Korg 9 transmits an interrogation signal to the transmitter 11 in synchronization with the input repetition frequency.
The output of the transmitter 11 outputs an interrogation signal from the antenna 25 via the duplexer 13 at the next stage.

The interrogation signal emitted from the antenna is received by a response device 27 mounted on an aircraft, etc., and transmits information such as the identification code, altitude or speed of the aircraft, and the transmitted signal is received by the antenna 25 again. Ru.

The received response signal is applied to one received signal processing circuit via the duplexer 13 and the receiver 17, and the output of the received signal processing circuit 19 is converted into a signal via the next stage decoder 23 and sent to the radar indicator 2 as a primary signal. Displayed with radar output.

Further, the received signal processing circuit 19 is controlled by a gate generation circuit 15 which inputs the output of the Gouda 9 and whose operating time is set by a setting switch 21.

In the identification interrogation device system configured in this way,
The repetition frequency of the primary radar device 1 is generated at predetermined intervals as shown in FIG. In this case, the synchronization circuit 7 of the interrogation device 3 thins out the input synchronization signal and generates a repetition frequency for the interrogation device as shown in FIG. A mode pulse consisting of <PL, P3 is generated as shown in FIG.

The mode pulse is emitted via the transmitting fill, duplexer 13 and antenna 25, and the reception area of the interrogation device 3 is as shown in FIG. 5(e). This is until just before the mode pulse P1 is generated.

For example, when an aircraft code pulse based on the mode pulse is input to the receiver 17 as shown in FIG. 5(f), the data is output to the radar indicator 2 via the received signal processing device 19 and decoder 23. As shown in FIGS. 5(e) and 5(b), the reception area of the interrogation bag W3 and the reception area of the primary radar device 1 are different from each other, and the code pulses received by the interrogation device 3 are As shown, the received signal processing circuit 19 due to the long reception area restriction signal.
When the response signal is applied to the radar indicator 2, the fifth
As shown in Figure (h), although the response signal (b) is from an aircraft that is far away, it is judged as a response signal from an aircraft that is located close to each other, and is displayed on the radar indicator 2. This is displayed as a false response signal indicating the presence of an aircraft in the vicinity, which is extremely dangerous for aircraft control identification.

In order to eliminate this problem, a multivibrator or digital register built into the gate generation circuit 15 is used,
By manually switching the switch 21, the reception area restriction signal of one of the received signal processing circuits is made short as shown in FIG.
Generally speaking, there is a method of controlling the operation of the radar indicator 2 and displaying only response signals from nearby aircraft on the radar indicator 2, as shown in FIG. It was getting worse.

The changeover switch 21 of the gate generation circuit is manually switched, and a plurality of switches are set according to the repetition frequency of the primary radar.

However, if the repetition frequency of the output signal from the repetition frequency generator of the primary radar is within the allowable maximum frequency of the interrogation device, such as pulses T3 and T4, the synchronization signal is not thinned out, so the synchronization signal cannot be synchronized with the synchronization signal. The repetition frequency of the interrogation device is generated by the interrogation device, and the code pulse of a distant aircraft (see Fig. 5(f) 2,
5) When the response signal must be displayed on the radar indicator, it is cut off by the interrogation device reception area restriction signal of the gate generator circuit as described above, so the response signal (: ), (to) data was not displayed and there was a problem that accurate data could not be obtained.

(Object of the invention) The present invention has been made in view of the above-mentioned problems, and includes:
When the repetition frequency of the primary radar is equal to or higher than the allowable maximum repetition frequency of the identification interrogation device, the reception area of the identification interrogation device is made to match that of the primary radar to prevent generation of false response signals due to reception area mismatch. , and to provide an identification interrogation device that can display all valid response signals on a radar indicator.

(Summary of the invention) In order to achieve this object, an identification interrogation device according to the present invention combines a primary radar device and an identification interrogation device,
In displaying aircraft or ship information output from an identification interrogation device superimposed on the indicator of the primary radar device, the synchronization signal output from the primary radar device and the information from the identification interrogation device are used. The present invention is characterized in that the code pulse of the aircraft or ship captured by the identification interrogation device is restricted from being supplied to the primary radar device based on the output mode pulse.

(Example) The present invention will be described in detail below based on the example shown in the drawings.

FIG. 1 is a diagram showing the configuration of an identification interrogation device according to the present invention, and similarly to FIG. FIG. 2 is a diagram showing the configuration, and also shows the identification question applied to an aircraft for ease of explanation.

In the figure, 31 is a primary radar device, 32 is a radar indicator, 33 is an interrogation device, and the primary radar device 1f
31 has a built-in repetition frequency generator 35, and the interrogation device 33 has a synchronization circuit 37, a Korg 39, and a transmitter 1141.
, duplexer 43, gate generation circuit 45, receiver 4
7. 4 received signal processing circuits, decoder 51, antenna 5
3. It is composed of delay circuits 55 and 57.

That is, when compared with the identification interrogation device shown in FIG. 4, the reception area restriction signal is generated by a reception area restriction circuit composed of a gate generation circuit and a switch for setting the operating time of the gate generation circuit. This is done by replacing the switch with a receiving area limiting circuit 59 to which two delay circuits 55 and 57 are newly added.

The synchronization circuit 37 inputs a synchronization signal from a repetition frequency generation circuit 35 built into the primary radar device, and divides or thins out the synchronization signal so that it falls within the maximum repetition frequency allowed by the interrogation device 33. A repetition frequency of the interrogation device is generated and inputted to the cog 39. The Korg 39 outputs an interrogation signal to the transmitter 41 in synchronization with the input repetition frequency, and the output of the transmission@41 is output from the antenna 53 via the duplexer 43 at the next stage.

The interrogation signal output from the antenna is received by a response device 61 mounted on the aircraft, which transmits information such as the identification code, altitude or speed of the aircraft, and then returns to the antenna 5.
Received by 3.

The received response signal is sent to the duplexer 43, the reception
The output of the received signal processing circuit 49 is converted into a signal via a decoder 51 at the next stage and displayed on the radar indicator 32 together with the primary radar output.

The received signal processing circuit 849 includes two delay circuits 55 and 5.
The delay circuit 55 is controlled by the repetition frequency generator 3 built in the primary radar device 31.
A synchronization signal, which is an output signal of No. 5, is input, and after being delayed for a predetermined time, the synchronization signal is output to the gate generation circuit 45.

On the other hand, the delay circuit 57 detects the P3 pulse among the mode pulses output from the kneader 39, and outputs the P3 pulse to the gate generation circuit after a predetermined delay time has elapsed after inputting the P3 pulse.

In the identification interrogation device system configured in this way,
The repetition frequency of the primary radar device 1 is generated at predetermined intervals as shown in FIG. In this case, the synchronization circuit 3 of the interrogation device 33
7 thins out the input synchronization signal and generates a repetition frequency for the interrogation device as shown in FIG.
As shown in d), a mode pulse consisting of Pl and P3 is generated.

The mode pulse is emitted via the transmitter 41, duplexer 43, and antenna 53, and the receiving area of the interrogation device 33 is as shown in FIG. 2(e). This is until just before the mode pulse P1 is generated.

Here, as shown in FIG. 2(d), mode pulses are output from the interrogation device 33, and code pulses of other aircraft for pulses A, B, and C are al, as shown in FIG. 2(f).
If a2, bl, b2, cl and C2, al, bl
and cl are response signals from the same nearby aircraft, and a2, b2, and C2 are response signals from the same aircraft located far away.

Therefore, a response signal as shown in FIG. Only data that matches the radar device reception area is applied.

That is, the delay circuit 5 constituting the five receiving area limiting circuits
7 detects the mode pulse P3 output from the Korg 39, and after a predetermined period of time has elapsed, outputs a signal to the next stage gate generation circuit 45, which opens the gate, while the primary radar Device synchronization signal (Figure 2 (a)
After a predetermined period of time has elapsed since the input of the synchronization signal (T1 to T5 pulses), the delay circuit 55 outputs a signal to the gate generation circuit 45 to turn off the gate of the reception area.

Thus, the output of the gate generating circuit 45 opens the gate by inputting the interrogation signal (pulses A, B, and C in Fig. 2(d)) of the interrogation device as shown in Fig. 2(g). Since the gate is turned off by inputting the synchronization signal (T1 to T5 pulses in FIG. 2(a)) of the primary radar device, the data output to the radar indicator 32 via the decoder 51 is the second As shown in figure (h), the code pulses of other aircraft are al, a2, bl, b2, cl.
and C2, excluding a2, so there is no need to input a false response signal, and it is possible to accurately display a response signal from an aircraft located far away.

The embodiment shown in Fig. 1 has been explained using a case in which the repetition frequency of the primary radar fluctuates, but this is intended to eliminate the influence of sea surface reflection or interference in the primary radar. If two or more primary radars with different repetition frequencies are used in combination with an identification interrogation device, the third
The interrogation device may be configured as shown in the figure.

That is, the synchronization signal of the primary radar device 63.65, which operates at a constant repetition frequency, is input to the synchronization circuit 37 of the identification interrogation device 33 via the switch circuit 67, and the output of the primary radar device 63.65 is also input to the synchronization circuit 37 of the identification interrogation device 33. The signal is output to the radar indicator 32 via six switch circuits. The switch circuits 67 and 6 are controlled by a signal output from a control circuit 71, and the control circuit 71 is linked to a selection switch (not shown) to determine which primary radar is to be used.

Therefore, the repetition frequency of the selected primary radar is input to the synchronization circuit 37, and based on the repetition frequency, the information of the identification interrogation device is superimposed on the indicator of the primary radar as described above.

Also, when the primary radar is switched, the switching i-t
The synchronization circuit generates the repetition frequency of the interrogation device based on the repetition frequency of the primary radar of &, so the pseudo response signal is
There is no risk of supply to the next radar (effect of the invention) Since the present invention is configured and functions as described above, it is possible to use a primary radar device with a varying repetition frequency or a plurality of primary radar devices with different repetition frequencies. When used in combination with an identification interrogation device, a false response signal is input to the primary radar device or is captured by the identification interrogation device based on the difference in repetition frequency between the primary radar device and the identification interrogation device. This is extremely effective in preventing valid information from being not transmitted to the primary radar device among the response signals received.

[Brief explanation of drawings]

FIG. 1 is a diagram showing one embodiment of the identification interrogation device according to the present invention, FIG. 2 is a time chart diagram explaining the signal state of the device shown in FIG. 1, and FIG. 3 is a diagram showing an embodiment of the identification interrogation device according to the present invention. FIG. 4 is a diagram showing a configuration of a conventional identification interrogation device, and FIG. 5 is a time chart illustrating signal states of the conventional device. 1.31.63.65...Primary radar device 2.32.
... Radar indicator 3.33 ... Identification interrogation device 5.35 ... Repetition frequency generator 7.37 ... Synchronization circuit 9. Three ... Korg 11, 41 ... Transmitter 13. 43...Duplexer 15.45...Gate generation circuit 17.47...One receiver, four...Received signal processing circuit 21...Switch 23.51...Decoder 25.53...・Antenna 27.61...Response device 55.57...5 delay circuits...Receiving area limiting circuit 67.6...Switch circuit 71...Control circuit

Claims (1)

[Claims] A primary radar device is combined with an identification interrogation device used for aircraft, ships, ground stations, etc., and aircraft and ship information output from the identification interrogation device is superimposed and displayed on the indicator of the primary radar device. The code pulse of the aircraft or ship captured by the identification interrogation device is transmitted to the primary radar device based on the synchronization signal output from the primary radar device and the mode pulse output from the identification interrogation device. An identification interrogation device characterized in that supply is restricted.