Realization of ultra wideband bandpass filter using new type of split-ring Defected Ground Structure

This paper introduces a new compact bandpass filter using a new Circular Split - Ring type Defected Ground Structures. A split ring Defected Ground Structure (DGS) when applied with a continuous microstrip line yields a very sharp stop band Lowpass filter. In the proposed structure, a T-shaped discontinuous microstrip line is included, which provides ultra wide passband. The passband of the proposed bandpass filter can be tuned by simply changing the radius of the inner ring of the split-ring DGS unit. This proposed structure provides an improved bandwidth when another split-ring DGS unit is included. A MoM based simulation is performed for the structures.