A new procedure for developing UMTS filters based on periodic structures

Abstract

A new method for developing UMTS filters for upload and download bands is proposed. The filters are based on a periodical resonator called the H-type resonator. Simulation results show that the relative mean error is less than 1.5%. The filter designed by this method has an insertion loss less than 1dB and provides low return loss in the bandpass. A periodic network analysis was used for designing the H-type resonator. We have also derived a lumped-element circuit model for the filter whose element's values are found by using genetic algorithms. It is shown that the filter has a suitable frequency response, and that it can be applied quite well in telecommunication systems.