The Research Of Frequency Synthesizer Technique In Micro Wave Data Communication System

In this article the author designs the PLL frequency synthesizer in micro wave band. It has the advantage of high stability high accuracy and small phase noise etc.In this article, the author introduces the characteristic and developing circs of the PLL technique, expatiates the basic work principle of PLL frequency synthesizer, analyzes the characteristic and builds the model of system phase noise etc. Then calculates the parameters of the loop filter based on the theory and analyzes the affection for the loop filter when change the parameters. This paper selects the elements according with the requirement of the system, processes the emulation of open loop gain, close loop gain, phase yawp and capture time etc. design the circuit based on the result of emulation. In the actual application, change the volume of the elements proper based on the circumstance, so it can satisfy the requirement of the actual project.