Compact size and low insertion loss Chebyshev-functionbandpassfilters using dual-mode patch resonators

A compact Chebyshev-function bandpass filter using dual-mode patch resonators is proposed. The filter presents 75% size reduction compared with the conventional Chebyshev bandpass filter using two square patch resonators. Because of inset feeding and only one coupling gap being required, the new filters can achieve a low insertion loss of 1.1 dB and reduce the fabrication uncertainties.