Performance monitoring for radar systems

Disclosed is a method and corresponding devices for monitoring the performance of a radar system (2, 4) provided with a shield 2 for protection against weathering (Radom) is equipped. For this purpose, a part of the emitted radar signal is modified and the radome after interaction with a possibly existing coating (5) (2) the reception system is supplied as a monitor signal. Influences of absorbing or reflecting coating (5) on the radome (2) change the monitor signal. By analyzing these changes, statements about the amount of through the covering (5) caused attenuation or reflection of the radar signals can be determined.