Design of novel attenuator structure with quad spiral shaped defected ground structure

A novel design of attenuator using quad spiral shaped defected ground structure (QSSDGS) and its related design formulae are proposed. Series resistors and quarter wave transmission line that has the role of inverter are synthesized to design the proposed attenuator. The proposed attenuator removes unexpected peaked insertion loss signal by its unique slope. It has various attenuation level and good return loss, so it can be used to the systems that have an unwanted peaked insertion loss. The various attenuation values are achieved due to pin diodes, as an example, 10-45 dB attenuation level presented in this work. The measured results of the proposed novel attenuator having QSSDGS are in a good agreement with theoretical expectation.