Modeling and Analysis of Bandwidth-Enhanced Multilayer 1-D EBG With Bandgap Aggregation for Power Noise Suppression

A circuit model of multilayer electromagnetic bandgap (EBG) structure with application on bandgap aggregation design is investigated in this paper. A design concept for bandgap aggregation is merging the lowest two bandgaps into an equivalent wide bandgap by narrowing central passband. This goal could be achieved by optimizing pitch and arrangement of power/ground vias. The theoretical circuit model which only focuses on cutoff frequencies is proposed for efficient bandgap prediction. The accuracy of the proposed model is validated by comparison with full-wave simulation and measurement results. By using the circuit model, mechanism of bandgap aggregation can be explained well, and the influence of structural parameters can also be studied easily. Furthermore, effect on limiting excitation of propagation modes by narrowing central passband is also validated for merging adjacent bandgaps. Test boards with unit cell size 2.03 mm × 3.94 mm are fabricated and measured to validate the design concepts. Both simulation and measurement show the wide bandgap in insertion loss results, which ranges from 1.27 GHz to above 10 GHz by merging even higher bandgaps.