Title:
DME RECEIVER
Document Type and Number:
Japanese Patent JP2606122
Kind Code:
B2
Abstract:
PURPOSE: To normally detect a question signal stronger than a CW jamming wave even if the CW jamming wave of a low level is continued.
CONSTITUTION: A receiver 6 has an IF amplifier 9, a detector 10, a decoder 11 and an ARRC 12. A CW detector 20 has an AGC circuit 24 for controlling the IF amplifier, a DC detector 21 for comparing a DC output voltage of the detector with first and second threshold values to output first and second detection signals, a comparator 22 for counting output pulse number of the decoder to decide whether it is a predetermined number or not, an AND circuit 23 for outputting an AND of the output of the comparator 22 and the first detection signal of the DC detector, and a switch circuit 25 for applying an output of the ARRC or the AGC circuit to the IF amplifier according to the output of the AND circuit 23. An alarm suppressing timer 40 generates an alarm suppression signal of two stages based on the output of the AND circuit and the second detection signal. A random pulse generator 30 mixes a random pulse with the output pulse of the decoder based on the output of the AND circuit.
Inventors:
Masami Iwaki
Application Number:
JP35153493A
Publication Date:
April 30, 1997
Filing Date:
December 29, 1993
Export Citation:
Assignee:
NEC
International Classes:
G01S7/36; G01S7/40; G01S13/76; (IPC1-7): G01S13/76; G01S7/36; G01S7/40
Domestic Patent References:
| JP5735777A | ||||
| JP52273B2 | ||||
| JP511865B2 | ||||
| JP648449Y2 |
Other References:
【文献】岡田實編「航空電子装置」<改訂板>、日刊工業新聞社、昭和53年1月30日、P.21~P.32
Attorney, Agent or Firm:
Yosuke Goto (2 outside)