Synthesis of Absorption Reflectionless Bandstop Filter and Its Design Using Multi-Layer Self-Packaged SCPW

In this paper, absorption reflectionless bandstop filter (ARBSF) is synthesized from low-pass prototypes, and the normalized parameters of the absorption low-pass prototypes are achieved by the symbiotic organisms search algorithm. One reflectionless bandstop filter is synthesized and designed by lumped-element circuit, while the other ARBSF is synthesized and implemented with multi-layer self-packaged suspended coplanar waveguide (SCPW), both are according to the desired specifications. The proposed ARBSF by using SCPW has been fabricated and measured. The experimental results demonstrate a wide fractional bandwidth of 59.45% and a S11 attenuation of no less than 10.88dB from DC to 8GHz. The ARBSF synthesis method and its implementation with SCPW have been verified.