| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To prevent the operation stop of a DME (distance measuring equipment) ground device by generating a transmission pulse of a normal answering signal, even if a CW (continuous wave) interfering waves that are not less than a predetermined signal level are input. <P>SOLUTION: A receiver 15 always monitors the signal level of a question signal for measurement, arriving from an aircraft (not shown) and received signal level of a diagnostic question signal generated by a question signal generating unit 18 for performing self diagnosis. When the CW interference waves arrive at the receiver 15, the signal level of the diagnostic question signal generated by the question signal generating unit 18 in a monitoring control device 17a is amplified by a variable amplifier 19, so that the signal level of the amplified diagnostic question signal is controlled to be higher than the signal level of the CW interfering wave. Consequently, even if the signal level of the CW interference waves become higher, a stable answering signal can be transmitted from a transmitter 16 to the aircraft through an antenna 11. Thus, the DME ground device 10a can continue to stably transmit distance measurement information to the aircraft. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
