Multi-Slit Electromagnetic Bandgap Power Plane for Wideband Noise Suppression

Abstract

A compact reduced size electromagnetic bandgap (EBG) structure with multiple narrow slits unitcell is presented. The new EBG structure is realized with a combination of alternating impedance EBG and multiple narrow slits in power plane. By concatenating 2 × 2 high frequency unitcells, a virtual low frequency EBG unitcell is created without changing the overall dimensions. In this configuration, the basic slit in the high frequency unitcell remained same and an additional Z-slit is added in parallel to the basic slit with larger dimensions by synthesizing a larger unitcell. This new configuration provides low onset frequency and wideband noise suppression with small unitcell dimensions. Measured and simulated results show noise suppression and isolation over 50 dB in most of the stop-band (0.7-3.5 GHz) and also exhibit low impedance, which is less than 1 Ω over the stop-band. Eye patterns are generated for analyzing signal integrity referenced to the solid power/ground plane and EBG plane. Maximum eye opening (MEO) and the maximum eye width (MEW) analyzed for the signal on EBG reference plane are presented and compared. The degradation of the MEO and MEW for the proposed EBG board is about 16.2 and 1%, respectively, with reference to the equivalent board with solid power plane.