Coupling matrix synthesis for dual-band bandpass filters based on admittance poles and zeros

摘要

A novel coupling matrix synthesis method for dual-band bandpass filter is presented in this article. The output admittance poles and zeros of the single-band filter prototype are firstly obtained and then transformed into dual-band prototype. Then the coupling matrix with predefined topology is optimized according to these poles and zeroes directly. This method can be achieved with no need to construct the characteristic function of dual-band filter and reconfigure the coupling matrix. Symmetric and asymmetric dual-band bandpass filter coupling matrix synthesis has been carried out to illustrate and validate this method. (c) 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:603-606, 2016