Effect of defected ground plane on the bandwidth of parallel line-coupled bandpass filter at 3.3 GHz

The effect of a defected ground plane made up of photonic band-gap structure of circular slots or patches of the radii r on the bandwidth of a parallel line- coupled bandpass filter, realized on a dielectric substrate and of 3.3 GHz center, frequency is highlighted in this study. The use of defected ground plane increases the filter bandwidth and allows its use on a broad-band frequency.