Array pattern synthesis by the method of alternating orthogonal projections: the general case

In the paper, the method of alternating orthogonal projections is derived for the problem of array pattern synthesis with multiple null constraints. The required complex weight vector is obtained via an iterative algorithm starting from the known `look direction¿¿. The projection operators required in the algorithm are shown to be easily computed from the `look direction¿¿ vector and the null-constraint vectors. A lower bound on the rate of convergence of the algorithm is also established.