Suppressor of erroneous target-does-not-answer displays - designed for interrogator of secondary radar transmitting coded interrogating signals

摘要

The response signals which are received are checked if they have been coded in a special way or not. In the case of erroneous or missing response signals, a 'Target-doesnot-answer' is displayed. An at least two-part antenna array is used for the interrogating and response signals and at least two transmission lines are provided. A monitoring device is connected to one transmission line. A part of the signal transmitted over the other transmission line is coupled out and is passed to the transmission line connected to the monitoring device via the beam coupling of the antennae.