Design of a novel compact microstrip interdigital filter based on aggressive space mapping

In this article, a compact embedded interdigital filter with six novel resonators and coplanar waveguide feeder is proposed. The novel resonator consists of a through silicon via and a microstrip line embedded in the substrate. The novel embedded interdigital filter is designed on a double-sided polished silicon wafer and optimized using aggressive space mapping. The center frequency of the filer is 5.9 GHz and the fractional 1 dB bandwidth is 33.9% (4.9-6.9 GHz). The insertion loss (IL) of the proposed filter is − 0.7 dB, and the return loss (RL) is −24 dbs. The proposed filter with a size of 4.5 mm X 6.5 mm has been verified in full-wave simulator HFSS, which can be mass-produced using MEMS technology.