Tapered photonic band gap microstrip filters

Summary form only given. We will review our research activity on photonic band gap (PBG) microstrip stop-band filters fabricated by etching in the ground plane circles with a square periodic pattern. The use of tapering techniques in the design of the periodic pattern has allowed a noticeable reduction of the sidelobe level and, therefore, the ripple in the passband, while the bending of the microstrip line has permitted the employment of a large number of periods in a reasonable circuit surface.