Wideband common-mode suppression filter design for multi differential signal pairs

In this paper, we proposed a wideband common-mode suppression filter for multi differential signal pairs. The method of the proposed design is utilized by using Defected Ground Structure (DGS) of two quarter-wavelength resonators with the mutual coupling effect to achieve the wideband common-mode suppression. For observing one pair differential signal lines in the frequency domain analysis, the differential-mode insertion loss are all above -3 dB from DC to 10 GHz. For the common-mode insertion loss, a wide common-mode suppression bandwidth is 4.2 GHz by using -15 dB definition. In multi differential signal pairs, we still have a wideband common-mode suppression of advantage.