JP4746438B2 - Secondary monitoring radar equipment - Google Patents

Description

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

The secondary surveillance radar device for air traffic control transmits an interrogation signal (1030 MHz) to a transponder (response device) on an aircraft as shown in, for example, Patent Document 1, and the interrogation signal decoded by the transponder is transmitted to the interrogation signal. The aircraft is identified by receiving a corresponding response signal (1090 MHz).
Japanese Patent Application Laid-Open No. 2005-69890.

  By the way, in the secondary monitoring radar device, the response signal coming from the aircraft is received by the antenna device, and the Σ video signal of the sum pattern of the received signals obtained at a plurality of locations of the antenna device is the difference pattern of the received signals. When the signal level is larger than the Δ video signal, the Σ video signal is input to the monopulse angle measurement processing unit to execute the monopulse angle measurement processing, and the Σ video signal is decoded by the decoding processing unit, and the sweep correlation processing unit Thus, the presence / absence of the correlation between the angle measurement value and the decoded data is determined, and the target information is detected from the determination result.

  However, in the case of the monopulse system, the data used for signal processing is data that satisfies the relationship of Σ> α · Δ, and therefore is smaller than the number of data actually received in the sum pattern (number of hits). For this reason, the detection rate of the target tends to be reduced in the sweep correlation processing unit.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a secondary monitoring radar apparatus capable of improving the target detection rate in the sweep correlation process.

In order to achieve the above object, the present invention is configured as follows.
When the signal from the target object is received by the antenna device, and the sum signal of each received signal obtained at multiple locations of the antenna device has a signal level greater than the difference signal of each received signal, the signal is summed by the monopulse angle measurement processing unit. The signal and difference signal are input to perform monopulse angle measurement processing, the sum signal is decoded by the decoding processing unit, and angle measurement data and decoding processing data are input by the sweep correlation processing unit to perform correlation processing. In the secondary monitoring radar apparatus that obtains target information about the target object from the processing result, a monopulse angle measurement processing unit is provided, and switching means for selectively switching on / off of the monopulse angle measurement processing, The signal level of the signal is compared with the signal level of the difference signal, and when the signal level of the sum signal is greater than the signal level of the difference signal based on the comparison result, the switching means is turned on to transmit the sum signal. Level when the following signal level of the difference signal, is obtained as comprising a switching control means for turning off the switching means, and a signal supply means for supplying to the decoding section the sum signal by bypassing the switching means.

  The signal supply means is provided with a bypass path that connects the preceding stage of the switching means and the decoding processing section.

  According to this configuration, the sum signal to be processed by the decode processing unit is supplied to the decode processing unit via a dedicated bypass path separately from the sum signal to be processed by the monopulse angle measurement processing unit. The sum signal can be processed separately by the decode processing unit and the monopulse angle measurement processing unit. Therefore, regardless of whether or not the signal level of the sum signal is greater than the signal level of the difference signal, all the sum signals can always be decoded in the decoding processing unit to obtain a large number of processing results. The detection rate of the target in the processing unit can be increased.

  When the switching control means uses an omni pattern signal different from the sum signal and the difference signal, the signal level of the sum signal is greater than the signal level of the difference signal and the signal level of the sum signal is greater than the signal level of the omni pattern signal Further, the switching means is turned on.

  According to this configuration, even when an omni pattern signal is used, the target detection rate in the sweep correlation processing unit can be increased.

  As described above in detail, according to the present invention, it is possible to provide a secondary monitoring radar apparatus capable of improving the target detection rate in the sweep correlation process.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(First embodiment)
FIG. 1 is a block diagram showing the configuration of the secondary monitoring radar apparatus according to the first embodiment of the present invention. In FIG. 1, reference numeral 11 denotes an antenna device that receives an RF signal from a target aircraft. In the antenna device 11, a sum pattern signal and a difference pattern signal of the received signal are obtained. Of these signals, the sum pattern signal is converted into a Σ video signal by the receiver 12 and supplied to the monopulse angle measurement processing unit 13, the decoding processing unit 14 and the level comparator 15. The signal of the difference pattern is converted into a Δ video signal by the receiver 16 and supplied to the monopulse angle measurement processing unit 13 and the level comparator 15 respectively. These Σ video signal and Δ video signal have the relationship shown in FIG.

  The level comparator 15 compares the amplitude level of the Σ video signal with the amplitude level of the Δ video signal. When the amplitude level of the Σ video signal is larger than the amplitude level of the Δ video signal, the level comparator 15 13 is output.

  The monopulse angle measurement processing unit 13 performs monopulse angle measurement processing using the Σ video signal and the Δ video signal when a gate signal is input.

  The decoding processing unit 14 receives the Σ video signal and executes decoding processing.

  Then, the monopulse value output from the monopulse angle measurement processing unit 13 and the decoding result output from the decoding processing unit 14 are supplied to the sweep correlation processing unit 17. The sweep correlation processing unit 17 inputs the monopulse value and the decoding result, executes the sweep correlation processing, and outputs target information based on the processing result.

Next, the operation in the above configuration will be described.
Previously, the secondary monitoring radar device shown in FIG. 3 was considered. In FIG. 3, the same parts as those in FIG.

  Each RF signal (sum pattern, difference pattern) received by the antenna device 11 is output as a Σ video signal and a Δ video signal by each receiver 12 and 16. The output video signals are compared in amplitude level by the level comparator 15 and only when the relationship of Σ> α · Δ is established, the switch S1 is turned on and the condition of Σ> α · Δ is satisfied. The following signal processing is performed on the Σ video signal being performed.

  In the signal processing, the monopulse angle processing unit 13 outputs a monopulse value, and the decode processing unit 14 outputs a decoding result.

  For both data, the sweep correlation processing unit 17 determines whether the received signal has a correlation, and outputs target information based on the determination result.

  In the case of the monopulse system, the data used for signal processing is data that satisfies the relationship of Σ> α · Δ, and is therefore smaller than the number of data actually received in the sum pattern (hit number). For this reason, the detection rate of the target tends to be reduced in the sweep correlation processing unit.

  Therefore, in the present embodiment, the switch S1 is realized by software processing in the monopulse angle measurement processing unit 13, and the receiver 12 and the monopulse angle measurement processing unit 13 are connected by the transmission line D1, The middle of the transmission line D1 to the decoding processing unit 14 are connected by the transmission line D2. That is, the Σ video signal supplied to the decode processing unit 14 bypasses the switching process of execution / stop of the monopulse angle measurement processing by the monopulse angle measurement processing unit 13.

  Therefore, the target detection rate in the sweep correlation processing unit 17 is higher than in the conventional case.

  As described above, in the first embodiment, a switch for switching execution / stop of processing of the monopulse angle measurement processing unit 13 is realized by software processing in the monopulse angle measurement processing unit 13, and the decoding processing unit 14. The Σ video signal is transferred by the dedicated transmission line D2 separately from the Σ video signal so as to be processed by the monopulse angle measurement processing unit 13, thereby the monopulse angle measurement processing unit 13 and the decoding processing unit 14 Can process Σ video signals separately.

  Therefore, regardless of whether or not the relationship of Σ> α · Δ is satisfied, the decoding processing unit 14 can always decode all Σ video signals to obtain a large number of processing results, and thereby the sweep correlation processing unit The target detection rate in 17 can be increased.

(Second Embodiment)
FIG. 4 is a block diagram showing a configuration of a secondary monitoring radar apparatus according to the second embodiment of the present invention. 4, the same parts as those in FIG. 1 are denoted by the same reference numerals and detailed description thereof is omitted.

  The second embodiment has a receiver 18 that receives an omni-pattern received signal, and a level comparator 19 that compares an Ω video signal that is an output signal of the receiver 18 with a Σ video signal. The difference from the first embodiment is that the outputs of the level comparator 19 and the level comparator 15 are input to the AND circuit 20 and the output signal is input to the monopulse angle measurement processing unit 13 as a gate signal.

  Each RF signal (sum pattern, difference pattern, omni pattern) received by the antenna device 11 is sent to the receivers 12, 16, and 18 by the Σ video signal, Δ video signal, and Ω video signal as shown in FIG. Is output as The amplitude level of the Σ video signal and the Δ video signal is compared by the level comparator 15 (Σ> α · Δ), and the amplitude level of the Σ video signal and the Ω video signal is compared by the level comparator 19 (Σ> β Ω), Σ> α · Δ and Σ> β · Ω satisfying the gate signal is output.

  The monopulse angle measurement processing unit 13 inputs a Σ video signal, a Δ video signal, and a gate signal, performs angle measurement processing on a Σ video signal satisfying Σ> α · Δ and Σ> β · Ω, and outputs a monopulse value. The Σ video signal is decoded by the decoding processing unit 14 and the decoding result is output. For both data, the presence / absence of correlation is determined for the signal received by the sweep correlation processing unit 17, and target information is output based on the determination result.

  The processing of the level comparator 15 and the level comparator 19 can be realized even by digital processing.

  As described above, the second embodiment is applied to RSLS (Receiver Side Lobe Suppression), and the number of data (number of hits) used in the sweep correlation process is reduced as in the first embodiment. Thus, it is possible to improve the target detection rate.

(Other embodiments)
Although the present invention has been described based on the respective embodiments, the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the gist thereof in the implementation stage. Moreover, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments. For example, some components may be deleted from all the components shown in each embodiment.

1 is a block diagram showing a configuration of a secondary monitoring radar apparatus according to a first embodiment of the present invention. The figure which shows the relationship between (SIGMA) video signal and (DELTA) video signal in the said 1st Embodiment. The block diagram which shows the structure of the secondary monitoring radar apparatus considered before. The block diagram which shows the structure of the secondary monitoring radar apparatus concerning the 2nd Embodiment of this invention. The figure which shows the relationship between (SIGMA) video signal, (DELTA) video signal, and (omega) video signal in the said 2nd Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Antenna apparatus, 12, 16, 18 ... Receiver, 13 ... Monopulse angle measurement part, 14 ... Decoding processing part, 15, 19 ... Level comparator, 17 ... Sweep correlation processing part, 20 ... AND circuit.

Claims (3)

Receiving means for receiving a signal from the target object;
Angle measurement processing for executing monopulse angle measurement processing by inputting the sum signal and the difference signal when the sum signal of the reception signals obtained at a plurality of locations of the receiving means has a signal level higher than the difference signal of the reception signals. Means,
Decoding means for decoding the sum signal;
Switching means provided in the angle measurement processing means for selectively switching on and off the monopulse angle measurement processing;
The signal level of the sum signal is compared with the signal level of the difference signal, and when the signal level of the sum signal is larger than the signal level of the difference signal based on the comparison result, the switching means is turned on, Switching control means for turning off the switching means when the signal level is equal to or lower than the signal level of the difference signal;
Signal supply means for bypassing the switching means and supplying the sum signal to the decode processing means ;
Angle measurement processing data obtained by the angle measurement processing means when the switching means is on, and decoding processing data obtained by the decoding processing means when the switching means is on and off, and performing correlation processing, A secondary monitoring radar apparatus comprising: correlation processing means for obtaining target information regarding the target object from the processing result . 2. The secondary monitoring radar apparatus according to claim 1, wherein the signal supply means includes a bypass path that connects a preceding stage of the switching means and the decoding processing means .   When the switching control unit uses an omni pattern signal different from the sum signal and the difference signal, the signal level of the sum signal is higher than the signal level of the difference signal, and the signal level of the sum signal is the omni pattern signal. 2. The secondary monitoring radar apparatus according to claim 1, wherein the switching means is turned on when the signal level is larger than the signal level.

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