Fractal CPW EBG filter with nonlinear distribution

In this paper, a double tapered fractal electromagnetic bandgap (DT-FEBG) technique in planar CPW structure is proposed and analyzed. The DT-FEBG structure of CPW not only improves the pass band performance but also generates two distant band-gaps. The fractal structure is realized by replacing the etched rectangular holes with a Minkowski loop generator. High resistivity silicon substrate and MEMS surface micromachining process are employed. The DT-FEBG structure shows insertion loss of less than 1.3 dB and the stop band rejection of around 44 dB.