Optimized Algorithm And Realization Of Passive Network Phase-frequency Characteristics

With the rapid development of digital communication currently, passive network phase response characteristic is requested more and more precisely. However phase response characteristic is conflict with amplitude response characteristic. How to obtain good group delay characteristics at Pass band and obtain much attenuation at Stop band is a question for discussion that relative scientists of all countries discuss and study at all times. Ancient approach is traditional network theory. Hard worked many years, the technology is mature.At initial stages of 1970s, people began to use circuit optimizationtechnology. Amplitude response characteristic can be optimized with it. With the consummation and improvement of this technology, much hard passive network design can be realized.This task comes from fund items of National Natural Science-A Bran-new Passive Networks Design Theory and Implementation Method. Passive network phase response characteristic is optimized with circuit optimization technology instead of custom network integrated design. Much prophased work is done, optimized technology of amplitude response characteristic go mature.The purpose of optimizing phase response characteristic is to obtain flat group delay characteristic at Pass band. Group delay is phase differential to frequency. So it is relatively difficult to optimize Group delay. The method that phase curve is optimized to a beeline is brought forward. A beeline is made with lease two-multiplied at phase-frequency Coordinates. This beeline is believed as phase perfect curve. Put phase curve close in upon this beeline. New component value is gained. The extent of close in upon is respected to precision of optimized program. New phase curve is gained according to new component value. A new beeline is madeas new phase perfect curve. Repeat this process till the extent of closein upon accord with requested condition. The examples prove this way is very good.