A multilayer dual-band filter using dual-mode resonators with second harmonic suppression

Abstract

A multilayer dual-band dual-mode bandpass filter with widely spaced passbands and using two independent square loop resonators is proposed. For improved stopband characteristics, the spurious second harmonic passband of the low frequency resonator is suppressed. The passbands are centered around 3 GHz and 9.35 GHz for application in a dual-frequency maritime radar. The simulated and measured results show good agreement.