Conductor Backed Coplanar Waveguide Bandpass Filter using Vertically Loaded Coupled Open-ended Stubs

In this paper, a Conductor backed coplanar waveguide (CB-CPW) 3
^rd
order bandpass filter is designed using Coupled open ended stub resonator placed vertically to the signal line. Vertically loaded open ended stubs are designed at quarter wavelength so as to behave like a short circuit at the input terminal thus giving a band-accepted response with lesser metallic area or minimum size. Four such coupled open ended resonators are placed in series and also in closely manner to provide greater field confinement of the proposed bandpass filter. The bandpass filter is designed for a centre frequency of 2.5 GHz with FBW of 97.89%, insertion loss of <; 0.5dB, rising and falling edge selectivity of 30.75 dB/GHz and 27.01dB/GHz respectively with a wide stopband of around 4GHz after the desired passband.