Design of Low Cost Substrate Integrated E-plane Waveguide Filter for C-band Applications

In this article, an E-plane bandpass filter (BPF) based upon substrate integrated E-plane waveguide (SIEW) is presented. Metal strip insertions into the middle layer of the SIEW structure constitute a novel E-plane BPF. A Jerusalem cross defected ground structure (DGS) is introduced into the ground layer to enhance filter bandwidth by shifting the passband and stopband. Further, two more rows of via holes were inserted for the betterment of filter performance. The filter is designed on Fr4 having a dielectric constant of 4.4. The final design of the filter achieves a 3 dB fractional bandwidth of 52.71%, return loss around −30 dB, and an almost 0 dB insertion loss in the passband.