Synthesis of arbitrary sidelobes sum and difference patterns with common excitation weights

The synthesis of sum and difference patterns is a canonical problem widely dealt with by researchers working on antenna array synthesis. As a matter of fact, they are used as transmitting/receiving devices for search-and-track systems (e.g., monopulse radars [1]). In this framework, several procedures have been proposed to reduce the complexity of the beam forming network aimed at generating at least a couple of radiation patterns. Among them, the generation of an optimal sum pattern and a difference one has been carried out by means of a sub-arraying strategy [2,3]. The simplification of the hardware complexity has also been addressed by sharing some excitations for the sum and difference channels [4].