Sparse array synthesis via Alternating Projections

The paper proposed a technique for the synthesis of sparse arrays based on a simple extension of the alternating projections algorithm that inherits all the desirable features of the technique, i.e. arbitrary 3D arrays can be synthesized from field specifications and excitation constraints specified via the convenient and general "mask" representation. In contrast, the works of Bucci et al. (2008) and Liu et al. (2008) require the more detailed information on the aperture distribution/goal pattern, which may be too demanding when specifications cannot be put in terms of "canonical" (e.g. pencil beam, flat top, etc.) patterns (in such cases obtaining a goal pattern amounts to a synthesis process itself). In addition the work of Liu et al. (2008) appears applicable to ID arrays only and does not allow control over the element excitations (dynamic range, phase jumps). The propose technique has similarities to that in the work of Keizer (2008) but provides better control on the element excitations and more general pattern specifications. On the negative side, this approach is iterative and thus more computationally intensive than the direct methods in the works of Bucci et al. (2008) and Liu et al. (2008).