Compact, deep, and wide rejection bandwidth low‐pass filter using open complementary split ring resonator

A deep and wide rejection bandwidth, sharp cutoff and compact low‐pass filter design using open complementary split ring resonator (OCSRR), and open stub is presented in this article.OCSRR is counterpart of the open split ring resonator. The proposed low‐pass filter consist of two OCSRR connected in series. The open stubs are attached on both sides of the OCSRR. At the 3 dB cutoff frequency of 1.08 GHz, the proposed filter offers a sharp rejection and wide rejection bandwidth of more than 20 dB up to six times the cutoff frequency. The filter size is very small as 0.22 λg × 0.18 λg, where λg is the guided wavelength at the cutoff frequency. The proposed filter is fabricated and tested; the experimental results are found to be in good agreement with the simulation results.