JP5135291B2 - Mode S secondary monitoring radar and aircraft monitoring method - Google Patents

Description

  The present invention relates to a Mode S secondary surveillance radar (SSR mode S) used in air traffic control and an aircraft surveillance method.

  The mode S secondary monitoring radar transmits information related to monitoring for air traffic control by transmitting an interrogation signal to a transponder mounted on an aircraft and receiving various information as response signals. It is an apparatus to acquire (for example, refer nonpatent literature 1).

  There are two types of transponders: ATCRBS (Air Traffic Control Rader Beacon System) transponders and Mode S transponders. In order to capture an aircraft equipped with an ATCRBS transponder (ATCRBS aircraft) and an aircraft equipped with a mode S transponder (mode S aircraft), the mode S secondary monitoring radar divides the beam dwell time into a plurality of sweeps, Each sweep is further divided into an all call period (collective question period) and a roll call period (individual question period), and different processing is performed in the all call period and the roll call period.

  The beam dwell time is a time corresponding to an angular range based on the rotational speed of the antenna and the transmission beam width of the mode S secondary monitoring radar that rotates and scans in the azimuth (azimuth) direction. It is determined.

  The mode S secondary monitoring radar transmits the mode A / C dedicated interrogation signal targeting the ATCRBS machine during the all call period, receives the mode A / C response signal for the mode A / C response signal, and monitors the ATCRBS machine. A mode S exclusive batch interrogation signal for the mode S machine is transmitted, and a mode S collective response signal is received to capture the mode S machine. In the roll call period, the mode S secondary monitoring radar transmits a mode S individual question signal targeting the mode S aircraft captured during the all call period, and in response thereto, the mode S transmitted from the mode S aircraft. The individual response signal is received, and the mode S machine is continuously monitored.

  In the mode S secondary monitoring radar, the direction of the monitored mode S machine calculated by transmitting and receiving the mode S individual question signal and the mode S individual response signal (or the mode S dedicated question signal and the mode S batch response signal) in the previous scan. The range (prediction range) for transmitting the mode S individual question signal is determined according to the predicted position based on the distance. Then, the mode S individual question signal is transmitted for each roll call period until the mode S individual response signal from the monitored mode S machine can be received within this prediction range. For example, as shown in FIG. 5A, scheduling of questions and responses is performed so that a mode S individual question signal is transmitted three times in total for three roll call periods to the mode S machine 100 to be monitored. Done.

  By the way, in the mode S secondary monitoring radar, there may occur a situation where the mode S individual response signal cannot be recognized due to non-reception of the mode S individual response signal or fruit interference. Further, depending on the positional relationship between the mode S secondary monitoring radar and the mode S aircraft, there may be cases where the mode S transponder side has not received any questions or missed responses. As a result, the Mode S secondary monitoring radar may not be able to detect the Mode S aircraft to be monitored, and monitoring may be interrupted.

  As described above, when the mode S individual response signal cannot be obtained and the monitoring of the mode S aircraft to be monitored is interrupted, the mode S secondary monitoring radar expands the prediction range in the next scan. For example, when the mode S individual response signal is not obtained according to the schedule even if the mode S individual question signal is transmitted three times as shown in FIG. 5 (a), for example, as shown in FIG. In the next scan, questions and responses are scheduled so that a mode S individual question signal is transmitted a total of five times over five roll call periods.

Michael C. Stevens, “Secondary Surveillance Radar, 1998, ISBN 0-89006-292-7

  As described above, when the monitoring by the individual question of the mode S machine to be monitored is interrupted, since the prediction range in the next scan is expanded, the occupancy ratio of the mode S machine in the beam schedule increases, and the beam Use efficiency of the schedule is reduced.

  If the mode S individual response signal cannot be obtained even when the prediction range is expanded, the prediction range is further expanded in the next scan. If the mode S individual response signal is not obtained for a predetermined scan or more, the mode S secondary monitoring radar will capture again with a batch question during the all-call period, but the mode S machine will continue to monitor with the individual question. During this period, the lockout function does not respond to collective questions from the Mode S secondary monitoring radar that is monitoring the Mode S aircraft.

  The lockout is controlled using the mode S individual question signal. The mode S machine monitors the mode S machine for about 18 seconds after receiving the mode S individual question signal including the lockout instruction. The mode S secondary monitoring radar does not respond to collective questions.

  Therefore, if the monitoring by the individual question of the mode S aircraft to be monitored is interrupted, while the mode S aircraft is locked out, it cannot be captured again by the batch question, and the mode existing in the monitoring airspace The S machine is not monitored. For this reason, it has been desired to improve the accuracy and reliability of monitoring of the mode S aircraft by the mode S secondary monitoring radar.

  The present invention has been made in view of the above, and provides a mode S secondary monitoring radar and an aircraft monitoring method capable of suppressing a decrease in the efficiency of use of a beam schedule and improving the accuracy and reliability of aircraft monitoring. The purpose is to do.

  In order to achieve the above object, the mode S secondary monitoring radar of the present invention transmits a mode S dedicated interrogation signal in the all call period via the antenna that scans the monitoring airspace, and individually transmits the mode S in the roll call period. The mode S collective response signal from the aircraft for the mode S exclusive interrogation signal is received and the mode S individual response signal from the aircraft for the mode S individual interrogation signal is received via the antenna that transmits the interrogation signal and the antenna. In addition, a receiving unit that receives the Mode S extended squitter transmitted from the aircraft, and a direction in which the monitored aircraft that is the aircraft that has transmitted the mode S batch response signal or the mode S individual response signal received by the receiving unit exists And a mode S response processing unit for detecting a distance from the antenna, and the mode S response processing unit Using the detected azimuth and distance of the monitored aircraft, the monitoring processing unit that calculates the predicted range of the monitored aircraft in the next scan of the antenna, and using the predicted range, the mode S individually in the next scan A channel management unit that performs scheduling for transmission of an interrogation signal and reception of a mode S individual response signal, and the monitoring processing unit transmits a mode from the monitored aircraft at a timing according to the scheduling by the channel management unit. When the S individual response signal is not obtained by the receiving unit and monitoring by the mode S individual response signal is interrupted, if the mode S extended squitter from the aircraft is received by the receiving unit, the mode S extended squitter The predicted range of the aircraft in the next scan is calculated using the position information of the included aircraft. The features.

  The aircraft monitoring method of the present invention receives a mode S batch response signal from the aircraft in response to the mode S dedicated batch question signal transmitted in the all call period via an antenna that scans the monitored airspace, and transmits it in the roll call period. Receiving a mode S individual response signal from the aircraft in response to the mode S individual inquiry signal, receiving a mode S extended squitter transmitted from the aircraft via the antenna, and a mode S batch response signal or mode S individual Detecting the azimuth of the monitored aircraft that is the aircraft that transmitted the response signal and the distance from the antenna, and using the azimuth and distance of the monitored aircraft, the monitored object in the next scan of the antenna Calculating the predicted range of the aircraft, and the predicted range Scheduling for transmission of the mode S individual question signal and reception of the mode S individual response signal in the next scan, and calculating the prediction range includes the step of calculating the prediction range at a timing according to scheduling. If the mode S individual response signal from the aircraft is not obtained and monitoring by the mode S individual response signal is interrupted, if the mode S extended squitter from the aircraft is received, the aircraft S included in the mode S extended squitter A predicted range of the aircraft in the next scan is calculated using the position information.

  According to the mode S secondary monitoring radar and the aircraft monitoring method of the present invention, it is possible to suppress a decrease in the use efficiency of the beam schedule and improve the accuracy and reliability of aircraft monitoring.

1 is a schematic configuration diagram of a mode S secondary monitoring radar and a mode S transponder mounted on an aircraft according to an embodiment of the present invention. It is a block diagram which shows the structure of the mode S secondary monitoring radar shown in FIG. It is a flowchart which shows the procedure which detects a mode S expansion squitter. It is a flowchart which shows operation | movement of the mode S secondary monitoring radar in case the monitoring of the mode S machine by a mode S separate response signal interrupts. It is a conceptual diagram for demonstrating expansion of the prediction range in a roll call period, (a) is a figure which shows the prediction range in normal time, (b) is a figure which shows the expanded prediction range.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of a mode S secondary monitoring radar according to an embodiment of the present invention and a mode S transponder mounted on an aircraft, and FIG. 2 is a configuration of the mode S secondary monitoring radar shown in FIG. FIG.

  As shown in FIG. 1, the mode S secondary monitoring radar 1 transmits an interrogation signal to the monitoring airspace via the antenna 11 that rotates and scans the monitoring airspace in the azimuth direction, and transmits the interrogation signal to the monitoring airspace. A transmission / reception unit 12 that receives a response signal from the receiver, and controls a question response, and generates a target report including the position of the aircraft in the monitored airspace, identification information, etc. based on the received response signal, and an external radar information processing system And a processing unit 13 for outputting the data. The antenna 11 has three types of horizontal patterns, sum (Σ), difference (Δ), and omni (Ω) necessary for monopulse angle measurement. The mode S secondary monitoring radar 1 is installed on the ground at a major point of an airport or an air route.

  The mode S transponder 2 generates the response signal for the received question signal, the antenna 21, the transmission / reception unit 22 that receives the question signal from the mode S secondary monitoring radar 1 via the antenna 21, and transmits the response signal. And a signal processing unit 23.

  Further, the mode S transponder 2 has a function of transmitting a mode S extended squitter including information necessary for broadcast-type automatic dependent monitoring (ADS-B) at intervals of about 0.5 seconds. And an ADS-B processing unit 24 for generating a mode S extended squitter. In the mode S extended squitter, the mode S machine equipped with the mode S transponder 2 is the position information indicating the current latitude and longitude acquired from the GNSS (Global Navigation Satellite System) and the like, and the mode S which is the identification information of the mode S machine. Address etc. are included.

  As shown in FIG. 2, the transmission / reception unit 12 of the mode S secondary monitoring radar 1 transmits / receives the interrogation signal generated by the transmission / reception switching unit 121 and the processing unit 13 to switch transmission / reception of signals in the transmission / reception unit 12. A transmission unit 122 that transmits via the unit 121; and a reception unit 123 that receives signals from the mode S transponder 2 and the ATCRBS transponder (not shown) via the antenna 11 and the transmission / reception switching unit 121.

  The receiving unit 123 is a multi-channel receiver that supports monopulse angle measurement processing, and the RF (Radio Frequency) signals of the three channels (Σ, Δ, Ω) received by the antenna 11 are set to 1 at the antenna boresight angle. The digital monopulse data corresponding to the pair 1 and the quantized video signal are converted and output.

  The processing unit 13 of the mode S secondary monitoring radar 1 includes a mode S response processing unit 131, an ATCRBS response processing unit 132, a monitoring processing unit 133, a channel management unit 134, and a transmission control unit 135.

  The mode S response processing unit 131 detects a mode S batch response signal, a mode S individual response signal, and a mode S extended squitter from a signal input as a quantized video signal from the receiving unit 123. The mode S collective response signal, the mode S individual response signal, and the mode S extended squitter are configured by a 4-pulse preamble and a data block, and the mode S response processing unit 131 performs a mode S collective response signal based on the preamble. The mode S individual response signal and the mode S extended squitter are detected.

  In addition, the mode S response processing unit 131 uses the digital monopulse data input from the receiving unit to detect the direction in which the target mode S machine that has transmitted the mode S batch response signal and the mode S individual response signal exists. The mode S response processing unit 131 also receives the mode S batch response signal, the arrival time of the mode S individual response signal, and the previously transmitted mode S dedicated question signal and the mode S individual question signal corresponding to these signals. Is used to calculate the distance from the antenna 11 to the target mode S machine.

  The mode S response processing unit 131 is a mode S batch response target including a mode S address in the data block of the mode S batch response signal and the direction and distance of the target mode S machine detected according to the mode S batch response signal. Information, and the mode S individual response target information including the mode S address in the data block of the mode S individual response signal and the azimuth and distance of the target mode S machine detected according to the mode S individual response signal In addition, the mode S extended squitter is output to the monitoring processing unit 133.

  The ATCRBS response processing unit 132 detects the mode A / C response signal from the signal input as the quantized video signal from the receiving unit 123, and uses the digital monopulse data input from the receiving unit in response to the mode A / C response signal. The direction in which the target ATCRBS machine equipped with the ATCRBS transponder (not shown) that transmitted the A / C response signal is detected is detected. The ATCRBS response processing unit 132 uses the arrival time of the mode A / C response signal and the transmission time of the previously transmitted mode A / C dedicated interrogation signal corresponding to the mode A / C response to The distance from 11 to the target aircraft is calculated.

  The ATCRBS response processing unit 132 determines the direction and distance of the target ATCRBS machine detected according to the mode A / C response signal, and the identification information and altitude information of the target ATCRBS machine included in the mode A / C response signal. Correlation between sweeps is taken, and responses from the same ATCRBS machine are collected and output to the monitoring processing unit 133 as mode A / C target information.

  The monitoring processing unit 133 generates a target report that summarizes the mode S batch response target information and the mode S individual response target information from the mode S response processing unit 131 and the mode A / C target information from the ATCRBS response processing unit 132. This is output to an external radar information processing system.

  In addition, the monitoring processing unit 133 uses the direction and distance of the target mode S machine detected by the mode S response processing unit 131 according to the mode S batch response signal or the mode S individual response signal in the next scan of the antenna 11. A predicted position based on the direction and distance of the target mode S aircraft and a predicted range corresponding thereto are calculated, and the result is notified to the channel management unit 134.

  Further, the monitoring processing unit 133 stores the mode S extended squitter acquired from the mode S response processing unit 131 in a memory (not shown), and from the same mode S machine as the transmission source of the stored mode S extended squitter. When a new mode S extended squitter is acquired, the mode S extended squitter is updated.

  When the monitoring processing unit 133 fails to obtain the mode S individual response signal from the mode S aircraft to be monitored by the individual question at the timing according to the scheduling by the channel management unit 134, the monitoring processing unit 133 expands the mode S extension from the aircraft. If the squitter is received by the receiving unit and stored in the memory, using the position information of the mode S machine included in the mode S extended squitter, the predicted position of the mode S machine in the next scan and the prediction range corresponding thereto Is calculated.

  The channel management unit 134 allocates the use of the RF channel in the mode S secondary monitoring radar 1 to the all call period and the roll call period. For the roll call period, the channel management unit 134 uses the prediction range of the target mode S machine calculated by the monitoring processing unit 133 to transmit the mode S individual question signal and the mode S individual in the roll call period of the next scan. Scheduling for reception of response signals.

  The transmission control unit 135 generates a question signal according to the scheduling of the channel management unit 134 and supplies this to the transmission unit 122.

  Next, the operation of the mode S secondary monitoring radar 1 will be described.

  During the all call period, the transmission control unit 135 generates a mode A / C dedicated batch question signal for the ATCRBS machine and a mode S dedicated question signal for the mode S machine under the management of the channel management unit 134. These are output to the transmission unit 122 and transmitted to the monitoring airspace via the transmission / reception switching unit 121 and the antenna 11.

  The ATCRBS transponder of the ATCRBS machine that has received the mode A / C dedicated batch interrogation signal transmits a mode A / C response signal including identification information and altitude information of the ATCRBS machine.

  The signal processing unit 23 of the mode S transponder 2 of the mode S machine that has received the mode S dedicated batch interrogation signal generates a mode S batch response signal that includes the mode S address of the own machine in the data block, and transmits this signal to the transmission / reception unit 22. To send through. At this time, the signal processing unit 23 uses the site ID, which is the identification information of the mode S secondary monitoring radar 1 included in the mode S dedicated batch interrogation signal, as the PI (Parity / Interrogator ID) of the data block of the mode S batch response signal. Overwrite field parity.

  The mode A / C response signal and the mode S collective response signal transmitted from the mode S transponder 2 are received by the antenna 11 of the mode S secondary monitoring radar 1 and output to the reception unit 123 via the transmission / reception switching unit 121. .

  The receiving unit 123 converts a signal input from the antenna 11 via the transmission / reception switching unit 121 into digital monopulse data and a quantized video signal, and these are converted to the mode S response processing unit 131 and the ATCRBS response processing unit 132. Output.

  The mode S response processing unit 131 detects the mode S batch response signal from the signal input as the quantized video signal from the receiving unit 123 based on the preamble pulse. Here, the mode S response processing unit 131 decodes the value overwritten on the parity of the PI field of the data block of the mode S batch response signal, so that the site ID (own site ID) of the mode S secondary monitoring radar 1 is obtained. ) Is a processing target as a normal response, and if it does not match its own site ID, the signal is discarded as a processing target. However, as will be described later, the mode S extended squitter is not discarded.

  Then, the mode S response processing unit 131 generates mode S batch response target information based on the mode S batch response signal to be processed and the digital monopulse data corresponding thereto, and outputs this to the monitoring processing unit 133. To do.

  The ATCRBS response processing unit 132 detects a mode A / C response signal from a signal input as a quantized video signal from the reception unit 123, and based on the mode A / C response signal, digital monopulse data corresponding to the mode A / C response signal, and the like. Then, the azimuth and distance of the target ATCRBS machine are detected.

  Then, the ATCRBS response processing unit 132 takes a correlation between sweeps for the detected direction and distance of the target ATCRBS machine, and the identification information and altitude information of the target ATCRBS machine included in the mode A / C response signal, Responses from the same ATCRBS machine are collectively output to the monitoring processing unit 133 as mode A / C target information.

  The monitoring processing unit 133 uses the direction and distance of the target mode S machine detected by the mode S response processing unit 131 according to the mode S batch response signal, and the direction of the target mode S machine in the next scan of the antenna 11 A predicted position based on the distance and a predicted range corresponding to the predicted position are calculated, and the result is notified to the channel management unit 134.

  The channel management unit 134 uses the prediction range of the target mode S machine calculated by the monitoring processing unit 133 to monitor the monitored mode S machine that is the transmission source of the mode S batch response signal received during the all-call period. In order to continue, scheduling for transmission of the mode S individual inquiry signal and reception of the mode S individual response signal in the next scan is performed.

  As described above, in the all call period, the mode S secondary monitoring radar 1 captures the mode S aircraft and the ATCRBS aircraft. The ATCRBS machine continues to be monitored during the all call period. As for the mode S machine, during the roll call period, the monitoring of the monitored mode S machine captured during the all call period is continued.

  In the roll call period, the transmission control unit 135 stores the mode S address of the monitored mode S machine acquired from the mode S batch response signal received in the all call period in the data block under the management of the channel management unit 134. In addition, a mode S individual question signal for the mode S machine to be monitored is generated, output to the transmission unit 122, and transmitted via the transmission / reception switching unit 121 and the antenna 11. The mode S individual question signal includes a lockout instruction. The mode S individual question signal is transmitted for each roll call period within the prediction range corresponding to the prediction position calculated by the monitoring processing unit 133.

  The signal processing unit 23 of the mode S transponder 2 of the mode S machine that has received the mode S individual question signal including the mode S address of the own machine generates a mode S individual response signal including the mode S address of the own machine in the data block. This is transmitted via the transmission / reception unit 22.

  The mode S individual response signal is received by the antenna 11 of the mode S secondary monitoring radar 1 and output to the receiving unit 123 via the transmission / reception switching unit 121.

  The receiving unit 123 converts a signal input from the antenna 11 via the transmission / reception switching unit 121 into digital monopulse data and a quantized video signal, and these are converted to the mode S response processing unit 131 and the ATCRBS response processing unit 132. Output.

  The mode S response processing unit 131 detects the mode S individual response signal from the signal input as the quantized video signal from the receiving unit 123 based on the preamble pulse. Here, when the mode S address in the data block of the mode S individual response signal matches the predicted address, the mode S response processing unit 131 sets the processing target as a normal response and does not match the predicted address. The signal is discarded as not being processed. The predicted address is the mode S address that should be included in the mode S individual response signal, and is the mode S address that was included in the corresponding mode S individual question signal. The ATCRBS response processing unit 132 does not perform processing even when a mode S individual response signal is input.

  The mode S response processing unit 131 generates mode S individual response target information based on the mode S individual response signal to be processed, digital monopulse data corresponding to the mode S individual response signal, and outputs the mode S individual response target information to the monitoring processing unit 133. To do.

  The monitoring processing unit 133 uses the azimuth and distance of the monitored mode S machine detected according to the mode S individual response signal in the mode S response processing unit 131, and the monitoring target mode S machine in the next scan of the antenna 11. A predicted position based on the azimuth and distance and a predicted range corresponding to the predicted position are calculated, and the result is notified to the channel management unit 134.

  The channel management unit 134 uses the prediction range of the monitored mode S machine calculated by the monitoring processing unit 133 to perform scheduling for transmission of the mode S individual question signal and reception of the mode S individual response signal in the next scan. Do.

  As described above, the mode S individual question signal is scheduled to be transmitted for each roll call period within the prediction range corresponding to the prediction position calculated by the monitoring processing unit 133. For this reason, the mode S individual question signal may be scheduled to be transmitted a plurality of times to one monitored mode S machine in one scan. In this case, for example, the first mode When the mode S individual response signal is obtained for the S individual question signal, the mode S response processing unit 131 notifies the channel management unit 134 to that effect, and the channel management unit 134 controls the transmission control unit 135 to scan the mode S individual response signal. Subsequent transmission of the mode S individual question signal in is omitted.

  As described above, the mode S secondary monitoring radar 1 receives the mode A / C response signal, the mode S batch response signal, and the mode S individual response signal used for capturing and monitoring the mode S and ATCRBS aircraft. In addition, the mode S extension squitter transmitted from the mode S transponder 2 at intervals of about 0.5 seconds is received regardless of the interrogation signal.

  Conventionally, even if the mode S extended squitter is received by the mode S secondary monitoring radar, it has been discarded as not being processed. In this embodiment, when the monitoring of the mode S machine by the mode S individual response signal is interrupted, the mode S extended squitter is used to continue monitoring of the mode S machine.

  Therefore, the mode S response processing unit 131 detects the mode S extended squitter in the procedure of the flowchart shown in FIG. 3 during the all call period. In the roll call period, the mode S response processing unit 131 accepts only the mode S individual response signal detected within the expected response time according to the scheduling of the channel management unit 134, and the mode S extended squitter is discarded. doing.

  In step S10 of FIG. 3, when receiving a signal via the antenna 11, the receiving unit 123 performs pairing of the RF signals of the three channels (Σ, Δ, Ω) received by the antenna 11 with respect to the angle of the antenna boresight. 1 is converted into digital monopulse data corresponding to 1 and a quantized video signal, and these are output.

  Next, in step S20, the mode S response processing unit 131 receives the output of the receiving unit 123, and based on the preamble pulse positioned before the data block of the signal input as the quantized video signal, the mode S batch response The signal and the mode S extended squitter are detected, and the result of decoding the value overwritten on the parity of the PI field of the data block of these signals matches the own site ID of the mode S secondary monitoring radar 1 (PI field). = Own site ID).

  When PI field = own site ID (step S20: YES), in step S30, the mode S response processing unit 131 determines that the received signal is a mode S batch response signal.

  If the PI field is not the own site ID (step S20: NO), in step S40, the mode S response processing unit 131 determines that the format number in the data block of the input signal is 17 or the format number of the mode S extended squitter. It is determined whether or not the result of decoding the value overwritten with the parity of the PI field is 0 (PI field = 0).

  When the format number is 17 or 18 and the PI field = 0 (step S40: YES), in step S50, the mode S response processing unit 131 determines that the received signal is the mode S extended squitter. .

  The mode S response processing unit 131 outputs the mode S extended squitter to the monitoring processing unit 133. The monitoring processing unit 133 stores the mode S extended squitter acquired from the mode S response processing unit 131 in a memory (not shown), and the mode S from the same mode S as the transmission source of the stored mode S extended squitter. When a new extended squitter is acquired, it is updated to the newly acquired mode S extended squitter, and the latest mode S extended squitter is always stored for each mode S machine.

  If the format number is neither 17 nor 18, or the PI field is not 0 (step S40: NO), in step S60, the mode S response processing unit 131 discards the received signal as a non-processing target.

  As described above, the mode S secondary monitoring radar 1 continues to monitor the monitored mode S aircraft captured in the all call period by the mode S individual question response in the roll call period. However, in the mode S secondary monitoring radar 1, there is a case where the mode S individual response signal is not received or the mode S transponder 2 side does not receive a question or misses a response. Mode S machine monitoring may be interrupted.

  The operation of the mode S secondary monitoring radar 1 when the monitoring of the mode S aircraft by the mode S individual response signal is interrupted will be described with reference to the flowchart shown in FIG.

  In step S110, the monitoring processing unit 133 determines whether there is a mode S machine to be monitored for which monitoring by the mode S individual response signal is interrupted.

  For example, in the transmission / reception unit 12, a mode is set once for each roll call period over a plurality of roll call periods for a certain mode S machine in one scan according to the scheduling by the channel management unit 134. When the S individual question signal is transmitted, but the mode S individual response signal from the corresponding mode S machine is not obtained in any roll call period, the monitoring processing unit 133 determines that the monitoring of the mode S machine is interrupted. To do. If there is a monitoring target mode S machine that has been interrupted (step S110: YES), the process proceeds to step S120, and if there is no monitoring target mode S machine (step S110: NO), the process proceeds to step S150.

  In step S120, the monitoring processing unit 133 determines whether or not the mode S extended squitter from the mode S machine whose monitoring is interrupted is stored in the memory. If stored (step S120: YES), the process proceeds to step S130. If not stored (step S120: NO), the process proceeds to step S140.

  In step S130, roll call processing using the mode S extended squitter is performed. In the roll call process using the mode S extended squitter, the monitoring processing unit 133 stores the position information of the mode S machine included in the latest mode S extended squitter from the mode S machine, which is stored in the memory, and is discontinued. Using this, the predicted position of the mode S machine in the next scan and the predicted range corresponding thereto are calculated, and the result is notified to the channel management unit 134. The channel management unit 134 then schedules the mode S individual question response in the next scan using the prediction range of the mode S machine to be monitored calculated by the monitoring processing unit 133.

  In step S140, a roll call process for recapture is performed. In the roll call process for re-acquisition, the monitoring processing unit 133 calculates the prediction range obtained by expanding the prediction range in the current scan as the prediction range of the mode S machine to be monitored in the next scan, and the result is channel management. Notification to the unit 134. The channel management unit 134 then schedules the mode S individual question response in the next scan using the expanded prediction range calculated by the monitoring processing unit 133.

  For example, in this scan, as shown in FIG. 5A, scheduling is performed so that the mode S machine 100 to be monitored is transmitted with a total of three mode S individual question signals over three roll call periods. In the next scan, for example, as shown in FIG. 5B, a total of five mode S individual question signals are transmitted over the five roll call periods to the monitored mode S machine 100, for example. In this way, the prediction range is expanded, and the query and response scheduling in the next scan is performed.

  If the mode S individual response signal is not obtained from the mode S machine whose monitoring is interrupted even if the prediction range is expanded, the prediction range is further expanded in the next scan. When the mode S individual response signal from the mode S machine for which the monitoring is interrupted for a predetermined scan or more cannot be obtained, the transmission of the mode S individual response signal to the mode S machine is stopped, and the mode S machine After the release, it is recaptured by the normal initial acquisition method in the all call period.

  In step S150, based on the mode S batch response signal or the mode S individual response signal, the monitoring processing unit 133 calculates the predicted position of the mode S machine to be monitored in the next scan and the prediction range corresponding thereto by the normal roll call process. Then, the channel management unit 134 schedules the mode S individual question response in the next scan using the prediction range.

  As described above, according to the present embodiment, when the mode S individual response signal from the mode S machine to be monitored cannot be obtained and monitoring by the mode S individual response signal cannot be continued, the prediction range is expanded. And using the position information of the mode S machine included in the mode S extended squitter, the predicted position of the mode S machine in the next scan and the prediction range corresponding thereto are calculated, and the mode S individual question response according to this is calculated. Thus, the monitoring of the mode S machine to be monitored is continued. This avoids a decrease in the beam schedule usage efficiency due to the expansion of the prediction range, and uses the Mode S extended squitter, which is transmitted almost regularly, for the continuation of monitoring, so that the accuracy and reliability of the monitoring of the Mode S machine can be improved. Can be improved.

DESCRIPTION OF SYMBOLS 1 Mode S secondary monitoring radar 11 Antenna 12 Transmission / reception part 121 Transmission / reception switching part 122 Transmission part 123 Reception part 13 Processing part 131 Mode S response processing part 132 ATCRBS response processing part 133 Monitoring processing part 134 Channel management part 135 Transmission control part 2 Mode S transponder 21 Antenna 22 Transceiver 23 Signal processor

Claims (4)

A transmitting unit that transmits a mode S dedicated interrogation signal in an all-call period and transmits a mode S individual question signal in a roll call period via an antenna that scans the monitoring airspace;
The mode S collective response signal from the aircraft for the mode S dedicated interrogation signal is received via the antenna, the mode S individual response signal from the aircraft to the mode S individual interrogation signal is received, and the mode transmitted from the aircraft A receiving unit for receiving the S extended squitter;
A mode S response processing unit for detecting the azimuth and distance from the antenna of the monitored aircraft that is the aircraft that has transmitted the mode S batch response signal or the mode S individual response signal received by the receiving unit;
A monitoring processing unit that calculates a predicted range of the monitoring target aircraft in the next scan of the antenna using the direction and distance of the monitoring target aircraft detected by the mode S response processing unit;
A channel management unit that performs scheduling for transmission of a mode S individual question signal and reception of a mode S individual response signal in the next scan using the prediction range;
When the monitoring processing unit is unable to obtain the mode S individual response signal from the monitored aircraft at the timing according to the scheduling by the channel management unit and the monitoring by the mode S individual response signal is interrupted, If the mode S extended squitter from the aircraft is received by the receiving unit, the predicted range of the aircraft in the next scan is calculated using the position information of the aircraft included in the mode S extended squitter. Mode S secondary monitoring radar.   The said monitoring process part calculates the said prediction range using the positional information on the aircraft contained in the newest mode S expansion squitter from the aircraft which the monitoring by the mode S separate response signal interrupted. Mode S secondary monitoring radar described in 1. The mode S collective response signal from the aircraft for the mode S dedicated interrogation signal transmitted in the all call period is received via the antenna that scans the monitoring airspace, and the mode S individual interrogation signal transmitted in the roll call period is received from the aircraft. Receiving a mode S individual response signal;
Receiving a Mode S extended squitter transmitted from an aircraft via the antenna;
Detecting the azimuth and distance from the antenna of the monitored aircraft that is the aircraft that transmitted the mode S batch response signal or the mode S individual response signal;
Calculating the predicted range of the monitored aircraft in the next scan of the antenna using the azimuth and distance of the monitored aircraft; and
Scheduling for transmission of mode S individual question signal and reception of mode S individual response signal in the next scan using the prediction range,
In the step of calculating the prediction range, when the mode S individual response signal from the aircraft to be monitored cannot be obtained at the timing according to the scheduling and the monitoring by the mode S individual response signal is interrupted, the mode S from the aircraft is calculated. An aircraft monitoring method, wherein if an extended squitter is received, the predicted range of the aircraft in the next scan is calculated using the position information of the aircraft included in the mode S extended squitter.   The step of calculating the prediction range calculates the prediction range using position information of the aircraft included in the latest Mode S extended squitter from an aircraft that has been monitored by the mode S individual response signal. The aircraft monitoring method according to claim 3.

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