SECONDARY MONITORING RADAR DEVICE AND ITS SLS/ISLS USING METHOD

摘要

PROBLEM TO BE SOLVED: To perform ISLS transmission without causing a decrease in coverage.;SOLUTION: In an SLS system, a P2 signal is transmitted from an SLS antenna 13 via a power amplifier 15 in time of SLS transmission. Since a switch 17 is then controlled to be normally opened, power loss can be reduced by a λ/2 open stub 16. In time of ISLS transmission, P1, P2 and P3 signals are transmitted from the SLS antenna 13 via the power amplifier 15. Then, the switch 17 is closed for the passage of P1 and P3 while being opened against the passage of P2 to cause a transmission channel to be connected in parallel to terminating resistance 18, thereby reducing characteristic impedance to half. As a result, the P1 and P3 signals can be transmitted from the SLS antenna 13 with their power lowered than that of the P2 signal. Since an INT system is independent of the SLS system, a question signal transmitted from an INT antenna 12 is transmitted with constant power by either SLS or ISLS, not changing SSR coverage.;COPYRIGHT: (C)2005,JPO&NCIPI