Antenna Array Analysis by Iterative DGFM-Based Local Solutions

The method of moments (MoM) is well suited to the electromagnetic analysis of antenna arrays, but solution cost grows rapidly with array size. This article concerns efficient MoM analysis of large antenna arrays with identical disjoint elements in arbitrary layouts. The domain Green’s function method (DGFM) is a domain decomposition method (DDM) for such arrays. Its unique benefit is that only local problems are solved to obtain an approximate global solution. Its main drawback is uncontrolled, problem-dependent solution errors. An improved scheme denoted iterative radius-based DGFM (IRB-DGFM) is formulated, in standard and residual-driven (RD) versions. Accuracy is improved by introducing local MoM domains, and solution error control is achieved via an iterative scheme, to obtain the true MoM solution to user-specified tolerance. Various computational cost reduction methods are proposed for the new formulations. Results show that the RD-IRB-DGFM is superior, yielding rapid convergence for diverse arrays. The methods are ideally suited to parallelization.