A Novel Partly Shielded Finite Ground CPW Low Pass Filter

Abstract

A novel partly shielded-finite ground coplanar waveguide (PS-FGCPW) low pass filter has been designed. The device consists of a PS-FGCPW loaded with metal stubs at periodic positions of the signal line. The width of the metal stubs has a sinusoidal variation as the function of the position along the signal line. By properly choosing the position and dimension of the loaded stubs, a wide stop band, more than four times the pass bandwidth, is obtained through the suppression of spurious frequencies inherent to the distributed structures. The prototype also exhibits very sharp cutoff, very low insertion loss in the passband, slow-wave effect and high isolation performance.