Periodically Corrugated Reference Planes for Common-Mode Noise Suppression in High-Speed Differential Signals

Abstract

We present a new scheme using a periodically corrugated reference plane (PCRP) for wideband suppression of a common mode (CM) noise in high-speed differential signals. In the PCRP, the CM return current path is designed to have a stepped impedance profile; thus, inducing the stopband for the CM noise. To analyze the CM noise suppression of the PCRP, an analytic dispersion equation is derived and verified by the full-wave simulation results and measurements. The PCRP experimentally demonstrates the CM noise suppression over the wideband frequency range from 5.3 to 10.4 GHz. In addition, good signal integrity characteristics for odd-mode propagation are verified by the measurements of the differential insertion loss and the eye diagram.