JP2010066069A - Secondary surveillance radar system - Google Patents

Abstract

[PROBLEMS] To provide a secondary monitoring radar device capable of automatically adjusting amplitude and phase characteristics between channels when a feeding system is changed, thereby ensuring long-term stability in operation. provide.
A pilot signal having a known amplitude / phase characteristic generated by a pilot signal generation circuit on an omni-pattern feeding system is pilot-injected in place of a sum pattern Σ and a difference pattern Δ obtained by an antenna apparatus. The circuit 8 injects into the channel of the sum pattern Σ and the channel of the difference pattern Δ, and the amplitude / phase detection circuit 12 detects the amplitude difference and phase difference between the channels by using the test signals of these channels. Then, by comparing with the reference value held in the holding unit 13 in advance by the comparison circuit 14, it is determined whether or not the power feeding system has changed due to a change in installation conditions or the like. The amplitude / phase characteristics of signals between channels are automatically adjusted.
[Selection] Figure 2

Description

  The present invention relates to a secondary monitoring radar device for air traffic control, for example.

As shown in Non-Patent Document 1, for example, the secondary surveillance radar device for air traffic control transmits a question signal to a transponder (response device) on a target aircraft and responds to the question signal from the transponder. The aircraft is identified by receiving a response signal. In this case, the distance and direction of the aircraft are obtained by the monopulse angle measurement method.
Secondary radar theory.

  By the way, when the secondary monitoring radar apparatus includes a multi-receiver used in the monopulse angle measurement method, the amplitude / phase characteristics between the channels (sum pattern, difference pattern) are improved in order to improve angle measurement accuracy. Must be the same. In this case, the amplitude / phase characteristics between the channels are measured, and the amplitude / phase adjustment circuit is adjusted by human work based on the measurement result. For this reason, it takes a lot of labor and time to complete the adjustment, it is difficult to ensure the adjustment accuracy, and it is difficult to ensure the long-term stability in operation.

  Further, when the power feeding system changes due to a change in installation conditions or the like, readjustment in the amplitude / phase adjustment circuit is necessary.

  Accordingly, an object of the present invention is to automatically adjust the amplitude and phase characteristics between the channels when the power feeding system changes, thereby ensuring long-term stability in operation. It is to provide a next monitoring radar device.

  In order to achieve the above object, a secondary monitoring radar apparatus according to the present invention receives a first signal from a target object by an antenna apparatus, and a sum signal of received signals obtained by a plurality of elements of the antenna apparatus. To the first system, the difference signal of each received signal is branched to the second system and input to the target processing unit, and an erroneous response to the first signal is prevented between the target object and the target processing unit. In the secondary monitoring radar apparatus that transmits / receives the second signal of the second target signal via the third system and obtains target information regarding the target object from the sum signal, the difference signal, and the second signal in the target processing unit, Provided is a test signal generating means for generating a test signal having known amplitude and phase characteristics with respect to the sum signal and the difference signal, and the first and first test signals instead of the sum signal and the difference signal when the test signal is transmitted. Test signal injected into two systems Note Means, detecting means for detecting the amplitude difference and phase difference of the test signal between the first and second systems when the test signal is transmitted, a compensation amount calculating means for obtaining a compensation amount from the detection result by the detecting means, and the compensation Compensation means for compensating the amplitude / phase characteristics of the test signal between the first and second systems based on the compensation amount obtained by the quantity calculation means and outputting the compensation signal to the target processing unit is provided.

  The compensation amount calculating means includes a reference value holding means for holding a reference value for uniquely determining an amplitude difference and a phase difference between the sum signal and the difference signal, and an amplitude difference, a phase difference and a reference value detected by the detecting means. Comparing means for obtaining a compensation amount by comparing with a reference value held by the holding means.

  According to this configuration, instead of the sum signal and the difference signal, a test signal having a known amplitude / phase characteristic sent from the third system is injected into the first system and the second system, and the first system and the second system are injected. Whether the power feeding system has changed due to changes in installation conditions, etc., by detecting the amplitude and phase differences of the signals between the systems using the system test signals and comparing them with the reference values held in advance. In the case of a change, the amplitude and phase characteristics of the test signal between systems due to the change are automatically compensated.

  Therefore, it is possible to automatically adjust the amplitude and phase characteristics between each channel when the power supply system changes without providing a new signal system or using special measuring instruments. It is possible to ensure long-term stability.

  As described above in detail, according to the present invention, it is possible to automatically adjust the amplitude and phase characteristics between the channels when the power feeding system changes, thereby ensuring long-term stability in operation. Therefore, it is possible to provide a secondary monitoring radar device capable of performing

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
First, prior to describing an embodiment according to the present invention, an operation principle thereof will be described.

  FIG. 1 is a signal characteristic diagram showing the principle of monopulse angle measurement of the secondary monitoring radar apparatus.

  In the monopulse angle measurement method of the secondary monitoring radar apparatus, in the process of measuring the azimuth of the target (showing 1T, 2T, and 3T in FIG. 1) from the monopulse signal, a sum pattern Σ obtained by adding the reception signals of a plurality of elements is subtracted. The difference pattern Δ is generated, the off-bore sight angle is calculated from the sum pattern Σ and the amplitude value of the difference pattern Δ, and the deviation of the target orientation from the center of the received beam is obtained.

  For example, as shown in FIG. 1A, when the target 2T is at the center of the reception beam, the sum pattern Σ has the maximum amplitude and the difference pattern Δ has the minimum amplitude. Further, the amplitude difference becomes maximum as shown in FIG. Further, the phase difference becomes zero as shown in FIG.

  When the angle is tilted by x ° from the center, the amplitude of the sum pattern Σ is smaller than the amplitude at the center, the amplitude of the difference pattern Δ is α, the ratio of the difference pattern Δ and the sum pattern Σ is calculated, and the deviation from the center x ° is obtained.

  Based on the above principle, an embodiment of the present invention will be described below.

(First embodiment)
FIG. 2 is a block diagram showing the configuration of the first embodiment of the secondary monitoring radar apparatus according to the present invention. In FIG. 2, an INT (interrogation) transmission signal necessary for identifying, for example, a target aircraft (not shown) is generated from the transmitter 1. This INT transmission signal is sent to the aircraft by the antenna device 3 through the circulator 2.

  Then, a response signal to the INT transmission signal is received by the antenna device 3 from the transponder of the aircraft. The antenna device 3 adds the received signals in the plurality of elements to generate an RF (radio frequency) signal of the sum pattern Σ, and subtracts the received signals to generate an RF signal of the difference pattern Δ.

  The sum pattern Σ RF signal obtained by the antenna apparatus 3 is supplied to the receiver 4 via the circulator 2, and the difference pattern RF signal is supplied directly to the receiver 4.

  On the other hand, an omni-pattern SLS (sidelobe suppression) transmission signal generated from the transmitter 1 is sent to the aircraft by the antenna device 3 via the circulator 6, and the omni pattern obtained by the antenna device 3 is obtained. The RF signal is supplied to the receiver 4 via the circulator 6. The omni-pattern SLS transmission signal is a signal for preventing an erroneous response to the INT transmission signal.

  Each RF signal (sum pattern Σ, difference pattern Δ, omni pattern) is amplified and frequency converted by the receiver 4 to become an IF (intermediate frequency) signal, which is input to the signal processing unit 5. The sum pattern Σ and the difference pattern Δ processed by the signal processing unit 5 are supplied to the target processing unit 9.

  The target processing unit 9 detects an off-pore site angle, that is, a target direction from the sum pattern Σ and the difference pattern Δ. The target processing unit 9 is supplied with an omni-pattern IF signal to prevent erroneous responses from the target.

  By the way, the signal processing unit 5 according to the present embodiment includes an amplitude / phase adjustment circuit 11 for adjusting the amplitude / phase characteristics between the channels (sum pattern Σ, difference pattern Δ), and between the channels (sum pattern). An amplitude / phase detection circuit 12 that detects a relative difference in amplitude / phase of Σ and difference pattern Δ, and a reference value that uniquely determines the amplitude / phase of each channel (sum pattern Σ, difference pattern Δ) in advance. A holding unit 13 and a comparison circuit 14 that compares the detection result of the amplitude / phase detection circuit 12 with a reference value held in the holding unit 13 are provided.

  In addition, a pilot signal generation circuit 7 is provided in the omni-pattern feeding system, and a pilot signal injection circuit 8 is provided between the antenna device 3 and the receiver 4. The pilot signal generation circuit 7 generates a pilot signal having known amplitude / phase characteristics with respect to the sum pattern Σ and the difference pattern Δ. This pilot signal is injected by the pilot signal injection circuit 8 into the feeding systems of the sum pattern Σ and the difference pattern Δ.

In the above-described configuration, processing operations that are characteristic of the configuration will be described below.
In the secondary monitoring radar apparatus considered before, as shown in FIG. 3, each RF signal (sum pattern Σ, difference pattern Δ) received by the antenna apparatus 3 is input to the receiver 4 to receive signals. Amplification and frequency conversion are performed and input to the target processing unit 21.

  The target processing unit 21 creates a monopulse angle measurement table from the relative amplitude / phase differences between the channels (sum pattern Σ, difference pattern Δ), and refers to the monopulse angle measurement table based on each received signal from the aircraft. To determine the orientation of the aircraft.

  In order to perform appropriate monopulse angle measurement, the amplitude / phase characteristics are adjusted by the amplitude / phase adjustment circuit 22 for the sum pattern Σ and the difference pattern Δ.

  In the conventional circuit system, readjustment is required by the amplitude / phase adjustment circuit 22 when the power supply system changes due to a change in installation conditions or the like. Since this adjustment is performed by human work, it takes a lot of time and effort.

  Therefore, in this embodiment, the pilot signal having known amplitude / phase characteristics with respect to the sum pattern Σ and the difference pattern Δ can be used to automatically adjust the amplitude / phase characteristics between channels when the power feeding system changes. I did it.

  4A is a transmission signal generated by the transmitter 1, FIG. 4B is a pilot signal generated by the pilot signal generation circuit 7, and FIGS. 4C and 4D are obtained by the antenna apparatus 3. An example of the sum pattern Σ and the difference pattern Δ is shown.

  In order to perform appropriate monopulse angle measurement, the amplitude and phase characteristics of the sum pattern Σ and the difference pattern Δ are adjusted. This is based on the received signal from the test transmission device, and the amplitude / phase adjustment of the signal processing unit 5 is performed. Adjustment is performed by the circuit 11. The relative amplitude / phase difference between the channels (sum pattern Σ, difference pattern Δ) after adjustment is detected by the amplitude / phase detection circuit 12, and the result is stored in the holding unit 13 as an initial value.

  Adjustment of the amplitude / phase characteristics after the reference value is set is performed by detecting the relative difference in amplitude / phase between the channels (sum pattern Σ, difference pattern Δ) of the pilot signal from the pilot signal generation circuit 7 and comparing it. The circuit 14 compares with the reference value. If there is a difference from the reference value as a result of the comparison, the compensation amount corresponding to the difference from the control signal, that is, the reference value, is kept until the difference from the reference value becomes zero for the amplitude / phase adjustment circuit 11. Is output.

  The amplitude / phase adjustment circuit 11 receives a pilot signal of each channel and a control signal (compensation amount), compensates the amplitude / phase characteristics of the pilot signal of each channel according to the control signal, and performs target processing on the compensated pilot signal. To the unit 9 and the amplitude / phase detection circuit 12.

  As described above, in the above-described embodiment, instead of the sum pattern Σ and the difference pattern Δ obtained by the antenna apparatus 3, a known amplitude / phase characteristic generated by the pilot signal generation circuit 7 on the omni-pattern feeding system is provided. The pilot signal is injected into the channel of the sum pattern Σ and the channel of the difference pattern Δ by the pilot injection circuit 8, and the amplitude difference of the signal between the channels is detected by the amplitude / phase detection circuit 12 using the pilot signals of these channels. And the phase difference is detected and compared with a reference value held in the holding unit 13 in advance by the comparison circuit 14 to determine whether or not the power feeding system has changed due to a change in installation conditions or the like. For example, the amplitude / phase characteristics of signals between channels due to the change are automatically adjusted.

  Therefore, it is possible to automatically adjust the amplitude and phase characteristics between each channel when the power supply system changes without installing a new power supply system or using a special measuring instrument. It is possible to ensure long-term stability.

  Further, the signal processing unit 5 can cope with aging by realizing the amplitude / phase adjustment circuit 11, the amplitude / phase detection circuit 12, the holding unit 13 and the comparison circuit 14 by digital processing.

(Second Embodiment)
FIG. 5 shows the configuration of the second embodiment of the secondary monitoring radar apparatus. In FIG. 5, the same parts as those in FIG. 2 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In this secondary monitoring radar apparatus, the output of the receiver 4 is input to the amplitude / phase detection circuit 12 while the output of the amplitude / phase adjustment circuit 11 is input to the amplitude / phase detection circuit 12 in the first embodiment. To enter.

(Other embodiments)
The present invention is not limited to the above embodiments. For example, by setting an appropriate signal level in the pilot signal injection circuit, it is possible to use the SLS transmission signal as a reference signal instead of the pilot signal generated from the pilot signal generation circuit. In this case, the SLS transmission signal is injected into the sum pattern channel and the difference pattern channel by the pilot signal injection circuit.

  Furthermore, in the implementation stage, the constituent elements can be modified and embodied without departing from the spirit of the invention. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment.

The signal characteristic figure which shows the principle of the monopulse angle measurement of the secondary monitoring radar apparatus concerning this invention. The block diagram which shows 1st Embodiment of the secondary monitoring radar apparatus concerning this invention. The block diagram which shows the structure of the secondary monitoring radar apparatus considered before. The figure which shows the waveform of the transmission signal, pilot signal, sum pattern, and difference pattern in the said 1st Embodiment. The block diagram which shows 2nd Embodiment of the secondary monitoring radar apparatus concerning this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Transmitter, 2 and 6 ... Circulator, 3 ... Antenna apparatus, 4 ... Receiver, 5 ... Signal processing part, 7 ... Pilot signal generation circuit, 8 ... Pilot signal injection circuit, 9 ... Target processing part, 11 ... Amplitude / Phase adjustment circuit, 12 ... amplitude / phase detection circuit, 13 ... holding unit, 14 ... comparison circuit.

Claims (5)

The first signal from the target object is received by the antenna device, and the sum signal of each received signal obtained by the plurality of elements of the antenna device is branched to the first system, and the difference signal of each received signal is branched to the second system And input and output to the target processing unit via the third system a second signal for preventing an erroneous response to the first signal between the target object and the target processing unit, In the secondary monitoring radar device that obtains target information about the target object from the sum signal, the difference signal, and the second signal in the target processing unit,
Test signal generating means provided in the third system for generating a test signal having known amplitude and phase characteristics for the sum signal and the difference signal,
Test signal injection means for injecting the test signal into the first and second systems in place of the sum signal and the difference signal when the test signal is transmitted;
Detecting means for detecting an amplitude difference and a phase difference of the test signal between the first and second systems when the test signal is transmitted;
Compensation amount calculating means for obtaining a compensation amount from the detection result by the detecting means;
Compensation means for compensating for the amplitude / phase characteristics of the test signal between the first and second systems based on the compensation amount obtained by the compensation amount computing means and outputting to the target processing unit. A secondary monitoring radar device. The first signal from the target object is received by the antenna device, and the sum signal of each received signal obtained by the plurality of elements of the antenna device is branched to the first system, and the difference signal of each received signal is branched to the second system And input and output to the target processing unit via the third system a second signal for preventing an erroneous response to the first signal between the target object and the target processing unit, In the secondary monitoring radar device that obtains target information about the target object from the sum signal, the difference signal, and the second signal in the target processing unit,
Test signal generating means provided in the third system for generating a test signal having known amplitude and phase characteristics for the sum signal and the difference signal,
Test signal injection means for injecting the test signal into the first and second systems in place of the sum signal and the difference signal when the test signal is transmitted;
Compensation for inputting the test signal obtained by the test signal injection means, compensating the amplitude / phase characteristics of the test signal between the first and second systems based on the given compensation amount, and outputting the compensation to the target processing unit Means,
Detecting means for detecting the amplitude difference and phase difference of the test signal between the first and second systems compensated by the compensating means;
A secondary monitoring radar apparatus comprising: a compensation amount calculation means for obtaining a compensation amount to be given to the compensation means from a detection result by the detection means. The first signal from the target object is received by the antenna device, and the sum signal of each received signal obtained by the plurality of elements of the antenna device is branched to the first system, and the difference signal of each received signal is branched to the second system And input and output to the target processing unit via the third system a second signal for preventing an erroneous response to the first signal between the target object and the target processing unit, In the secondary monitoring radar device that obtains target information about the target object from the sum signal, the difference signal, and the second signal in the target processing unit,
Injection means for injecting the second signal into the first and second systems instead of the sum signal and the difference signal;
Detecting means for detecting an amplitude difference and a phase difference of signals between the first and second systems;
Compensation amount calculating means for obtaining a compensation amount from the detection result by the detecting means;
Compensating means for compensating for the amplitude / phase characteristics of the signal between the first and second systems based on the compensation amount obtained by the compensation amount computing means and outputting to the target processing section. A secondary monitoring radar device. The first signal from the target object is received by the antenna device, and the sum signal of each received signal obtained by the plurality of elements of the antenna device is branched to the first system, and the difference signal of each received signal is branched to the second system And input to the target processing unit, and transmits and receives the second signal for preventing an erroneous response to the first signal between the target object and the target processing unit via the third system, In the secondary monitoring radar device that obtains target information about the target object from the sum signal, the difference signal, and the second signal in the target processing unit,
Injection means for injecting the second signal into the first and second systems instead of the sum signal and the difference signal;
Compensation means for inputting the signal obtained by the injection means, compensating for the amplitude / phase characteristics of the signal between the first and second systems based on a given compensation amount, and outputting to the target processing section;
Detecting means for detecting an amplitude difference and a phase difference of signals between the first and second systems compensated by the compensating means;
A secondary monitoring radar apparatus comprising: a compensation amount calculation means for obtaining a compensation amount to be given to the compensation means from a detection result by the detection means. The compensation amount calculating means includes a reference value holding means for holding a reference value that uniquely determines an amplitude difference and a phase difference between the sum signal and the difference signal in advance, and an amplitude difference and a phase difference detected by the detecting means. 5. The secondary monitoring radar according to claim 1, further comprising: a comparison unit that obtains the compensation amount by comparing the reference value held by the reference value holding unit. apparatus.

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