Compact dual-band LTCC filter using folded resonators

Abstract

This paper presents a dual-band bandpass compact low temperature co-fired ceramic (LTCC) filter using folded resonators. The passband of the proposed filter centred at 2.45 GHz and 5.2 GHz, and three transmission zeroes are generated. It is easy to couple the Π-type resonators of the proposed structure compared with the planar form. The filter is miniaturized by using the LTCC multilayers structure, and the size of the circuit is 5.5× 5.1 × 2.3 mm3.