 A novel wideband common mode, CM, suppression filter has been proposed for high-speed transmission. It uses a combination of a mushroom structure and a defected corrugated reference plane structure, MDCRP, which generates more resonance frequencies in the CM current return path. These resonances generate a wider CM noise suppression performance. Simulation was used to determine the optimal geometric parameters for the MDCRP structure. Experimental results confirmed that the full wave simulation results matched those obtained from actual measurements. This novel filter provides excellent signal integrity with a measured insertion loss of less than minus 2.306 dB from DC to 21 GHz in differential mode, DM. Its CM noise suppression performance is also impressive with a measured improvement of over minus 10 dB from 5.09 GHz to 20.62 GHz. Furthermore, its fractional bandwidth is 120.8% and its CM noise is reduced by 64.5%. This filter supports a 20 gigabits per second transmission rate with complete differential signal transmission capability. As such, it meets the current computer and server system products design needs. This article was authored by Cheng Kuyue, Ding Bing Lin and Hsin Piao Lin. We are article.tv. Links in the description below.