Design of S-band Frequency Tunable Substrate Integrated Waveguide Band Pass Filter with EBG Slots

In this paper, the design of a frequency tunable band pass filter using Substrate Integrated Waveguide (SIW) technology is presented for S-band using PIN Diodes. Frequency tunability is introduced by varying the biasing of the PIN diodes, which are connected across perturbing vias. This in turn varies the resonant frequency of the filter. The filter design includes a U-shaped Electromagnetic Band Gap (EBG) slot to improve the stopband and passband characteristics. The performance is analyzed by observing the S-parameters of the designed filter. Two tuning frequencies were obtained for the designed filter at 3.45 GHz and 3.70 GHz with insertion loss of −0.75 dB and −0.81 dB, respectively.