Sharif Digital Repository

In this paper our purpose is introducing new method for designing dual pass band filters that it can make the tuning steps easier and more determinant. This method based on matrix coupling theory. We assign a specific arrange for desired coupling matrix that it helps to our porpuse. After design any effect of matrix element has been apparent, so tune steps can be more routine. we used half cut cylinder resonators for designing dual band filter that it decrease size and mass of the filter intensily.After designing dual band filter we can transform its out put to achieve diplexer. New diplexer method also has been introduced at the end of paper