Helical-via-type mushroom EBG structure for size reduction

A novel electromagnetic band gap (EBG) scheme is presented for size reduction. The proposed structure can be considered as a modification of typical mushroom structure with the shorted vertical pin replaced by a helical via. Transmission characteristics of the proposed topology are obtained by using suspending microstrip method. The helical-via-type mushroom structure provides additional degrees of freedom to control the band gap characteristics and owns feature of size reduction. Simulation and experimental results are used to verify the prediction.