A Novel Unidirectional Radiator with Superb UWB Characteristics for X-band Phased Array Applications

We propose a compact, CPWG-fed, single layer UWB-ring-slot antenna for X-band phased array applications. Superb EM-characteristics are obtained for the whole designed frequency band: 1) nearly perfect linear phase, 2) small phase delay, 3) negligible phase dispersion characteristics, nearly constant group delay, (deviation is of sub-nanosecond level), 4) UWB impedance bandwidth, 5) in-band flat, balanced and constant power delivery, 6) nearly constant and repeatable radiation patterns in array plane, 8) over 90% of efficiency, 9) simple and compact, 10) symmetrical fed-and-excited radiator with "uni-directional" radiation pattern, andl 1) with smallest-form-factor. Other excellent UWB antenna-related characteristics obtained with this design will also be reported.