A Low-noise Frequency-agile Ku-band Frequency Synthesizer for Wideband Frequency Hopping Communication System

In this paper, a low-noise frequency-agile Ku-band frequency synthesizer for the wideband frequency hopping communication system is proposed. Three analog PLL (phase locked loop), two of which constitute an in-loop mixing architecture scheme, are used to provide the carrier frequency in wide low-noise frequency coverage. With out-of-loop and in-loop mixing architecture, the carrier frequency source implemented in the paper has superior performance on frequency jitter, which can be shown as the phase noise level less than -107.3dBc/Hz@1kHz when the carrier frequency is between 12 GHz to 15 GHz in 2 MHz steps. The spurious level is below -64 dBc, and the frequency hopping time is less than 40 us.