Abstract :
Doppler radar systems frequently impose severe demands on spectral purity in order to discriminate between targets and clutter. In the case of radars operating at X-band, the region from a few hundred Hz out to a few kHz from carrier is normally the most critical as far as phase noise and spurious signal performance are concerned. The author presents a 25 channel fast switching X-band frequency agile source design capable of achieving a repeatable phase noise performance of -125 dBc/Hz at 1 kHz from carrier. Given that the current state of the art for this type of unit is around -110 dBc/Hz at 1 kHz, the design described represents a significant advance in the technology