JP2009236881A - Ground device of dme, and method for monitoring its response efficiency - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ground device of DME for continuously monitoring response efficiency, and its response-efficiency monitoring method. <P>SOLUTION: A variable gain amplifier 40 is provided in the middle of a transfer route for false inquiry pulses generated by a monitor and control section 30 to a transponder section 20. The level of the false inquiry pulses is always kept at a level higher than a reception level threshold of the inquiry pulses regardless of execution of response pulse rate control, by controlling the gain of the variable gain amplifier 40. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a DME (Distance Measuring Equipment) ground device that is a radio navigation facility and a method for monitoring the response efficiency thereof.

  The DME ground device transmits a response pulse after a lapse of a certain time after receiving an interrogation pulse from the aircraft. The aircraft can measure the distance from the DME ground unit based on the time from transmission of the interrogation pulse to reception of the response pulse. In addition, each pulse contains various coded information and is an indispensable device for the safe operation of an aircraft.

  For DME ground equipment, it is stipulated that the response efficiency is maintained at 70% or more by regulation. The response efficiency is an index indicating the rate at which the response pulse can be reliably returned with respect to the received inquiry pulse. However, if a plurality of interrogation pulses are transmitted at the same time and interfere, a response pulse cannot be returned. The interrogation pulse received within the blanking time from the reception of the interrogation pulse to the transmission of the response pulse is ignored. For these reasons, if there are too many aircraft that issue interrogation pulses to one DME ground device, the response efficiency will be lowered and it will be difficult to maintain it at 70%.

Therefore, if the number of interrogation pulses from the aircraft is too large, the reception sensitivity of the DME ground device is reduced, and the response efficiency is kept above the specified value by not receiving interrogation pulses from distant aircraft. It has been. A technology related to this has been filed as Patent Document 1. Hereinafter, this technique is referred to as response pulse rate control.
Japanese Patent Application No. 2007-145282

  By the way, the DME ground device has a function of monitoring the transmission pulse (response pulse) waveform, the transmission level, the system delay time, the response efficiency, and the like, and the normality of the transponder is confirmed by this function. For example, for monitoring the response efficiency, a pseudo interrogation pulse that looks like an interrogation pulse of an aircraft is generated inside the apparatus and internally transferred to a transponder. In response, the transponder of the DME ground device transmits a response pulse. The response efficiency can be calculated from the ratio of the response pulse number to the pseudo question pulse number. The transmission level of the pseudo interrogation pulse is fixed to a value that is, for example, about 6 dB higher than the minimum reception level.

  However, in the response pulse rate control mode, the reception level threshold value of the interrogation pulse is intentionally increased. Therefore, if this level threshold value is higher than the minimum reception level by 6 dB or more, the pseudo interrogation pulse is masked and is not processed. Since response efficiency cannot be monitored in such a state, it is necessary to take some measures.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a DME ground device capable of continuously monitoring response efficiency and a response efficiency monitoring method thereof.

  In order to achieve the above object, according to one aspect of the present invention, in a DME ground device including a transponder unit that transmits a response pulse to a received interrogation pulse, and a monitoring control unit that monitors the state of the transponder unit, The transponder unit transmits a response pulse only to an interrogation pulse that has arrived at a level equal to or higher than a threshold value, and varies the threshold according to the reception rate of the interrogation pulse, thereby transmitting the response pulse. The monitoring control unit generates a pseudo interrogation pulse and transfers the pseudo interrogation pulse to the transponder unit, and the ratio of the pseudo interrogation pulse and the response pulse to the pseudo interrogation pulse is determined from the ratio of the transponder unit. A monitoring unit that monitors response efficiency; and a transfer level of the pseudo interrogation pulse is set to a level equal to or higher than the threshold value. DME ground apparatus is provided, characterized in that it comprises a holding portion for holding the.

  By taking such a measure, even if the reception level threshold value of the interrogation pulse is increased in the response pulse rate control mode, the transfer level of the pseudo interrogation pulse is raised in such a way as to follow it. As a result, it is possible to prevent the pseudo interrogation pulse from being processed, and thus it is possible to constantly monitor the response efficiency.

  According to the present invention, a DME ground device capable of continuously monitoring response efficiency and a response efficiency monitoring method thereof can be provided.

  FIG. 1 is a functional block diagram showing an embodiment of a DME ground device according to the present invention. The DME ground device 10 includes a transponder unit 20 that transmits a response pulse to the received interrogation pulse, and a monitoring control unit 30 that monitors the state of the transponder unit 20. Among these, the transponder unit 20 performs wireless communication with an aircraft (not shown) via the antenna 11. The monitoring control unit 30 generates a pseudo question pulse. The pseudo interrogation pulse is transferred to the transponder unit 20 via the directional coupler 12 inside the apparatus. At that time, the transfer level of the pseudo interrogation pulse is controlled by the variable gain amplifier 40 provided in the transfer path.

  In FIG. 1, an interrogation pulse from an aircraft reaches a transponder unit 20 via an antenna 11 and a directional coupler 12, and is further sent to an IF conversion unit 22 via a circulator 21. The IF conversion unit 22 converts the received pulse into an IF (Intermediate Frequency) signal. The IF signal is converted into data by an analog / digital (AD) conversion unit 23 and then processed by the processing unit 24. The processing unit 24 generates a response pulse for the received interrogation signal. The response pulse is amplified by the pulse transmission unit 25 and returned to the aircraft via the circulator 21, the directional coupler 12, and the antenna 11.

  In the transponder unit 20, the processing unit 24 reduces the reception sensitivity of the interrogation pulse when the number of interrogation pulse times (rate) transmitted from a plurality of aircraft becomes excessive. That is, the processing unit 24 sets a threshold for the reception level of the inquiry pulse, and sends a response pulse only to the inquiry pulse that arrives at a level equal to or higher than this threshold. By doing so, the response efficiency is kept above a certain value.

  Further, the processing unit 24 varies this threshold according to the reception rate of the inquiry pulse. That is, the higher the reception rate, the higher the threshold level so that response efficiency of at least 70% is maintained. In this way, processing in the response pulse rate control mode is performed.

  By the way, the monitoring control unit 30 includes a monitoring processing unit 30a and a level control unit 30b as processing functions according to this embodiment. The monitor processing unit 30 a generates a pseudo question pulse and transfers it to the transponder unit 20. Then, the response efficiency of the transponder unit 20 is monitored from the ratio between the pseudo interrogation pulse and the response pulse corresponding thereto.

  The level control unit 30b controls the gain of the variable gain amplifier 40 to change the transfer level of the pseudo interrogation pulse. That is, the level control unit 30 b acquires from the transponder unit 20 the reception level threshold value of the inquiry pulse that is changed by the processing unit 24. Then, the gain of the variable gain amplifier 40 is controlled so as to keep the transfer level of the pseudo interrogation pulse at or above this threshold. As a result, regardless of the operation in the response pulse rate control mode, the transponder unit 20 always receives and processes the transmitted pseudo question pulse. Therefore, a response pulse is always returned with respect to the pseudo interrogation pulse, and the response efficiency can be continuously monitored continuously.

  As described above, in this embodiment, the variable gain amplifier 40 is provided in the transfer path of the pseudo interrogation pulse generated by the monitoring controller 30 to the transponder unit 20. Then, the gain of the variable gain amplifier 40 is controlled so that the level of the pseudo interrogation pulse is always kept at a level higher than the reception level threshold value of the interrogation pulse regardless of the implementation of the response pulse rate control. . Since it did in this way, a pseudo question pulse is not ignored in the transponder part 20, and response efficiency can be measured continuously. Accordingly, it is possible to provide a DME ground device capable of continuously monitoring response efficiency and a response efficiency monitoring method thereof.

  In addition, this invention is not limited to the said embodiment, In an implementation stage, a component can be deform | transformed and embodied in the range which does not deviate from the summary. 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 functional block diagram which shows embodiment of the DME ground apparatus concerning this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... DME ground apparatus, 20 ... Transponder part, 30 ... Monitoring control part, 11 ... Antenna, 12 ... Directional coupler, 21 ... Circulator, 22 ... IF conversion part, 23 ... Analog / digital conversion part, 24 ... Processing part , 25 ... pulse transmission unit, 30a ... monitor processing unit, 30b ... level control unit, 40 ... variable gain amplifier

Claims (4)

In a DME (Distance Measuring Equipment) ground device comprising a transponder that sends a response pulse to a received interrogation pulse and a monitoring controller that monitors the state of the transponder.
The transponder part is
A response processing unit for sending a response pulse only to a question pulse that has arrived at a level equal to or higher than a threshold;
A rate control unit that controls the transmission rate of the response pulse by varying the threshold according to the reception rate of the interrogation pulse;
The monitoring controller is
A pseudo-question pulse is generated and transferred to the transponder unit, and a monitor unit that monitors the response efficiency of the transponder unit from the ratio of the pseudo-question pulse and the response pulse to the pseudo-question pulse;
A DME ground device comprising: a holding unit that holds a transfer level of the pseudo interrogation pulse at a level equal to or higher than the threshold value. The DME ground device according to claim 1, wherein the rate control unit varies the threshold so as to keep the response efficiency at 70% or more. A response processing unit that transmits a response pulse only to an interrogation pulse that has arrived at a level equal to or higher than a threshold; and a rate control that controls the response pulse transmission rate by varying the threshold according to the reception rate of the interrogation pulse A DME (Distance Measuring Equipment) ground device comprising a unit, and monitoring the response efficiency of the ground device,
Generate a pseudo question pulse and transfer it to the response processor,
Monitoring the response efficiency from the ratio of the pseudo interrogation pulse and the response pulse to the pseudo interrogation pulse;
A response efficiency monitoring method, wherein a transfer level of the pseudo interrogation pulse is maintained at a level equal to or higher than the threshold value. 4. The response efficiency monitoring method according to claim 3, wherein the threshold value is varied to keep the response efficiency at 70% or more.

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