An Ultra-Wideband Common-Mode Suppression Filter Based on S-DBCSRR for High-Speed Differential Signals

In this letter, an ultra-wideband common mode filter is proposed for high-speed differential signal transmission. By etching a slot in the inner patch of a double slit complementary split ring resonator (S-DBCSRR), the noise rejection bandwidth can be expanded. The equivalent circuit model and surface current distribution are given to explain the working principle of the filter. From the simulated and measured results, it is found that the fractional bandwidth of the presented filter is 92% with a noise suppression level of 20 dB, and the differential signal can propagate with little degradation.