Methods are available for the independent synthesis of array excitations which provide either optimum sum or optimum difference pattern performance. In the paper a technique is described to effect the simultaneous synthesis of both sum and difference patterns of a linear antenna array which utilises sub-arraying to increase the number of degrees of freedom above that available with the usual two-section feed network. The particular approach (referred to here as excitation matching) attempts to obtain an optimum sum (difference) and a ‘best compromise’ difference (sum) pattern, by dealing directly with the independently optimum excitations and appropriately adjusting the sub-array weights.