Desensitization of spread spectrum radar systems by far off the carrier noise generation in millimeter sources

The sensitivity of a spread spectrum radar system is greatly reduced by noise which is generated far off the carrier frequency. The far removed intrinsic noise generation effects in millimeter sources observed in experimental FM-CW radar systems are examined. A simple relationship is established for system desensitization caused by improperly tuned Gunn oscillators having bias circuit noise in contrast to the noise limited case. Techniques have now been developed to successfully suppress these effects.