Coincident phase center ultra wideband array of dual polarized flared notch elements

NRL has devised a coincident phase center array that interleaves orthogonal flared notches along their centers which allows for larger geometries and so larger bandwidth. The NRL array has perfect symmetry which leads to outstanding isolation between the polarizations. Simulated results were presented which show that over a 6 to 1 bandwidth, the active reflection coefficient will be lower than -10 dB, and the isolation between the orthogonal polarizations will be better than 40 dB. A 20 x 20 array has been constructed and is being characterized. So far no problems have been encountered which would lead us to doubt predictions. Finally, successful completion of this array will facilitate work on a simplified time delay beam steering technique devised by one of the authors, J.B.L. Rao.