A novel miniaturized waveguide all pole band pass filter using confined multi‐layered frequency selective surfaces

Abstract

This letter presents a novel technique for realizing waveguide all pole band pass filters (BPFs). To the best of the authors’ knowledge this work is the first of its kind to confine the frequency selective surface (FSS) within a waveguide to realize highly miniatured high‐performance BPF. For the proof of the concept, a sixth‐order all pole BPF is realized at 10 GHz with a fractional bandwidth of 10%. The measured peak insertion loss of the filter is better than 1.2 dB and return loss is better than 15 dB. The proposed concept yields a remarkable miniaturization with an internal volume reduction of 30%. Space mapping technique has been adopted to systematically design the filter.