Simulation And Design Of A X Band Frequency Synthesizer

Frequency synthesizer is one of the most important part of the communication system,which plays important role at wide application scenarios.In Engineering implementation area,although PLL at X band has been widely used and researched,few research focus on the X band PLL used in communication area,but most of the research focus on the application of the X band PLL in radar applications.The requirement about a PLL in radar application and communication application are different mostly.The difficulty to design a X band PLL is that,normally we only get the demand of the system other than the specific demands about a PLL,which means the engineer has to consider the chain topology and the device performance,get the specific demand of a frequency synthesizer used in a communication system.For example,narrow band,flexible,and low cost,which result in the difference between the simulation result and the reality.This article begins from how to get the specific demand about a PLL through the system demand,described the design method of a PLL in X band frequency in detail.Firstly,we start from the system demand,get the specific demand of a X band frequency synthesizer through the analysis of the performance level of each block and the demand of the chain.Secondly,we constructed the math and circuit model of the X band frequency synthesizer used in communication based on the combination of Laplace transform and simulation soft,analyzed the key factor and the change rule of a frequency synthesizer,constructed the system scheme of the frequency synthesizer.Further,we picked the key chip,performed PCB level simulation,and got the simulation results.Thirdly,we made a X band frequency synthesizer based on the simulation results,the measurements results and the simulation results were almost the same,which means the design flow we proposed in this thesis is of applicability and reference value.