Abstract-A very compact low temperature co-fired ceramic (LTCC) dual-band filter is designed based on the proposed novel crosscoupling structure in this paper. A six-pole dual-band filter with four transmission zeros is synthesized using an analytical procedure. By incorporating the proposed novel cross-coupling structure and analyzing the coupling characteristic, the dual-band filter is realized with canonical topology in multilayer LTCC. It is demonstrated by the simulation and experiment that the proposed dual-band filter has both compact size and good selectivity.
Abstract-A compact planar 4 × 4 microstrip Butler matrix is proposed in this paper. It is a wideband beam-forming network with the advantages of compact size, low cost and ease of fabrication. Threebranch line couplers with lumped-distributed elements are adopted to reduce the size, and multi-U-shaped coupled-line Schiffman phase shifters are designed to get good transmission and phase performances. The Butler matrix is fabricated and measured, and a good agreement is found between the simulated and measured results, which makes it very attractive for wideband multi-beam antenna applications.
Abstract-This paper presents a wideband circular polarization antenna for Global Navigation Satellite System (GNSS). By exciting four slots etched along each edge of a square ground with equal amplitude and 90 • phase difference, good circular polarization performance is achieved. A novel radiation element, composed of back-side slot and front-side monopole, is proposed to realize a wideband radiation. Meanwhile, the feed network composed of Schiffman phase shifters and Wilkinson power dividers maintains this wideband performance. A backed cavity is used to suppress the backward radiation, therefore enhances the frontward gain. Measured results of the fabricated antenna show good agreement with the simulated ones. The main advantages of this antenna include its wide bandwidth, good circular polarization, high front to back ratio, low cost, and easy fabrication, which make it very attractive for GNSS terrestrial applications.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.