Design of Ultra-wide Stop-band Dgs Low-pass Filter Using Meander- and Multilayer- Techniques

This article presents a new dog-bone defected ground structure (DGS) for low-pass filter (LPF) applications with widerejection band and low-insertion loss in the pass-band region. The prototype LPF consists of three dog-bone cells in the ground plane with an open stub on the top layer acting as a compensated capacitor. The prototype LPF is then realized as a multilayer structure to enhance the filter response and reduce its size. The size reduction of the proposed multilayer LPF is about 34% more than the conventional one. The proposed filter has been fabricated and measured. Good agreement can be realized between the electromagnetic simulation and the measurement results. To minimize the difference between the simulation and measurement results, and at the same time to reduce the loss in the pass-band region, a modification to the topology of the structure with the aid of the meander idea is used. The meander-filter presents advantages of compactness, low insertion loss, and high out-band suppression. The dog-bone DGS cell is then used as a photonic band gap structure to minimize the coupling between two probe-fed patch antennas and to improve the two antenna element array efficiency. VC 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1276– 1281, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27541