A triplexer design based on coupled resonators approach for wireless communication

Design and computer simulation results of a triplexer based on coupled resonator approach are reported in this paper. Six resonators are interconnected in such a way as to yield three outputs with passbands centered at 1.8 GHz, 2.1 GHz and 2.45 GHz covering the GSM, UMTS and IEEE 802.11b wireless bands. Each output presents a Chebyshev ripple level of 0.04321 dB and fractional bandwidth of 2.5 %, 3.3 % and 2.3 % for the left, center and right passbands, respectively . A gradient-based local optimization technique is here utilized to determine the coupling coefficients by minimizing a proposed Cost Function.