Performance Characteristics of SIW-Based BPF with Square-Shaped CSRR Incorporation

In this paper, performance characteristics of band-pass filter (BPF) developed based on substrate-integrated-waveguide (SIW) with complimentary-split ring-resonator (CSSR) incorporation is presented. An array of 12 square-shaped CSRRs configured in 2 columns by 6 rows is incorporated into the SIW surface of BPF to attain an optimal desirable passband performance. Some attempts to investigate the coupling characteristic are carried out by controlling the distance between CSRRs in the column, as well as between the array of CSRR in the row. Based on the optimal value of coupling coefficient, configuration of the proposed SIW-based BPF is then realized and experimentally characterized. The measured result of scattering (S) parameters shows that the realized BPF has the 3-dB working bandwidth of 1.52 GHz ranges from the frequency of 2.36 GHz to 3.88 GHz, or its fractional bandwidth of 50.23%. This result is comparable to the simulated one, whereby the value of coupling coefficient in this configuration is 0.28.