Systems and methods are taught for blocking the propagation of electromagnetic waves in parallel-plate waveguide (PPW) structures. Periodic arrays of resonant vias are used to create broadband high frequency stop bands in the PPW, while permitting DC and low frequency waves to propagate. Particular embodiments...http://www.google.de/patents/US7123118?utm_source=gb-gplus-sharePatent US7123118 - Systems and methods for blocking microwave propagation in parallel plate structures utilizing cluster vias
