Ka band band-stop filter based on complementary split ring and SIW resonators

In this paper, a band-stop filter in Ka band is proposed, which is based on substrate integrated waveguide(SIW) resonators and complementary split ring resonators(CSRR). The SIW resonators filter is provided with high pass characteristics. We show that near the resonance point, the impedance characteristics is significantly increased by CSRR. Therefore, we can combine the SIW resonators and CSRRs to change the high pass characteristics and significantly improve the rejection level of the stop-band by etching CSRRs on the top layer in the SIW resonators. The simulated insertion loss of the filter is around - 1dB and the return loss is less than -15dB at the frequency range of 26 to 29 GHz and 32.5 to 36 GHz. In addition, the rejection level is above -20dB from 29.5 to 32GHz.