Design of a Dual-Band Rectangular Waveguide Filter based on Direct Coupled

This paper presents how to design and simulate a passband rectangular waveguide filters based on direct coupled resonators operating at 12 GHz. The modeled filters are characterized by a cross coupling that produces a single attenuation pole at finite frequency used to shape the bandpass response. Resonators provide bandpass filter designs with a pseudo-elliptic response using HFSS simulators. Transmission zeros are obtained through coupling between the fundamental mode and high mode. The filter structures are validated leading to obtain transmission zeros close to the passband. The simulated waveguide filters with a centre frequency exhibit an insertion loss of -0.4/0.3dB and a return loss of −20/23dB for a bandwidth ranging from 11.85GHz to 12.15GHz that shows good electromagnetic responses for the simulated filters.