Uniplanar four-element Vivaldi array fed by a coplanar waveguide

This letter describes the design of a uniplanar parallel-series-fed linear array of Vivaldi antennas. Matching conditions have been optimized with an equivalent-circuit model. The array exhibits 12dBi gain in the substrate pl ane, 80% radiation efficiency, and low cross polarization over 5% bandwidth centered at 4.2GHz. (C) 2001 John Wiley & Sons, Inc.