Microstrip notch filters based on open interconnected split ring resonators (OISRRs)

An open interconnected split ring resonator (OISRR) is proposed for use in compact microstrip notch filters. This OISRR behaves as a shunt series L C resonant circuit and allows a parallel connection with a microstrip line. This cell presents half the resonant frequency of the split ring resonator (SRR) and, therefore, is electrically very small. The measured results show a 3 dB stop-band bandwidth lower than 2 % with more than 10 dB insertion loss in the stop band. This OISRR can be useful in microwave communication systems. © 2013 Springer-Verlag Berlin Heidelberg.