Ultra wideband dual polarised arrays

The paper describes two printed ultra wideband fixed-beam dual polarised arrays. The first consists of plain diamond dipoles, each with an integrated unbalanced-to-balanced transformer (balun), formed by a tapered microstrip line. The second array modifies the first by introducing a shorted Minkowski fractal pattern onto the diamond elements forming the dipoles. Both perform well over a 3:1 bandwidth with low cross-polarisation. The design and performance of these arrays are discussed.