The Simulation And Frequency Spectrum Measurement On The Key Circuit Of RF Front-End

The CAD of RF front-end circuit is a rather particular issue. On one hand, the influence of distributed and packaged parameters of components and circuits can be ignored no more; on the other hand, the popular RF components are still vastly employing the same encapsulation as ordinary electronic components, and manufactories are usually not rendering the complete s-parameter for them. Neither the CAD methods for microwave circuit nor that for general electronics are not so applicable. Thereby my thesis is concentrated on the CAD method of key RF front-end circuit based on PSPICE. Based on the design of whole RF teaching lab system, this thesis establised RF transistor PSPICE model and macro model, including distributed parameter and encapsulation parameter. Making use of the models mentioned above, we simulate oscillation frequency of RF oscillator, output amplitude, power supply voltage, offset voltage and relations with other circuit parameters, simulating results accord with the experiment tests. Depending on the foregoing analytical model, we dispute RF modulator and mixer, output waveform and circuit improvement project, probe into the relatives on the key RF front-end circuit in depth. At the same time, we carry on another simulation on the RF filter, we finally have a good result in our thoughts. The merits of cad technology based on PSPICE described in this thesis are as follows: the parts of all kinds of components and electrical parameter are very easy, making a thorough simulation of dc state. What's more, PSPICE has been adopted as the main standard of circuit simulation, we can use the free demo version in the teaching lab condition.