Tunable - compact bandstop defected ground structure (DGS) with lumped element

This paper introduces new compact DGS Resonators and an approach, in which lumped and tunable element are add within the DGS Resonating structure in certain places to obtain compact high performance and tunable filters. A comparison study of the combined resonators is presented to identify their relative advantages, disadvantages and their suitability for specific applications like cygnus system for seismic waves. A good agreement between the results of measurements and those produced from both the finite difference time domain method (FDTD) MATLAB code and the EM Simulation program are achieved.