Continuous signal surveillance radar system - has two continuous signal radar stations with two object size/distance characteristics

摘要

The second radar sender is opposite the first, directed towards it, with the two beams partially overlapping in order to define the surveillance zone. A first receiver is near to the first sender and delivers a first output signal in accordance with Doppler shifted echo signals from the object moving in the first beam. Its size and distance from the first sender are sufficient to cross its characteristic. A second receiver near the second sender delivers a similar signal from the object moving in the second beam. Logic circuits are connected to the two receivers and deliver a warning signal when only one receiver delivers an output signal, and an alarm signal when both receivers simultaneously deliver output signals.