Abstract: A radar detector includes features to reduce emissions such as those typically generated by the detector's local oscillator. Two low noise amplifiers (LNA's), operating in X band and a combined K/Ka band, respectively amplify X and K/Ka band signals from separate antennae, and deliver those signals over separate, elongated and narrow signal paths to X and K/Ka mixers, where those signals are mixed with local oscillator (LO) signals to produce IF for detection. The elongated, narrow signal paths from the antennae to the mixers reduce LO emissions, and those emissions are further reduced by incorporating radar absorbers between the circuit board and detector case along the antenna-mixer path, including radar absorptive paint on the circuit board itself along this path, and sealing the case with a conductive sealing gasket.

Abstract: A system and method providing millimeter wave front end circuitry utilizing waveguide E-plane bandpass filters for both out of band frequency rejection as well as reverse and spurious propagation of in band signals. Accordingly, a conductive base plate is formed having various waveguides. Circuit boards of the front end circuitry are disposed in ones of the waveguides which reject in band frequencies in order to prevent undesired coupling of signals. Additionally, waveguides rejecting out of band frequencies are coupled to the circuit boards in order to provide bandpass filters utilized by the front end circuitry.