Frequency synthesizer for atmospheric microwave radiation spectrum analyzer

The phase-locked loop (PLL) frequency synthesizer is a critical device of radiometer. It works as a local oscillator (LO) for channel selection in the receivers but suffers phase noise including reference spurs. this article gives a detailed design and implementation of frequency synthesizer in the atmospheric microwave radiation spectrum analyzer. Base on the reasonable design, we can select the appropriate device circuit and achieve it. The 8-channel frequency synthesizer of K-band atmospheric microwave radiation spectrum analyzer has completed It has a low phase noise and frequency step.