Spherical wave expansion technique [comment and reply]

Comments on a paper by Chen, Simpson and Ho (see IEE Proc. H vol. 139, p. 7, 1992) that addressed the spherical wave expansion (SWE) technique for solving radiation and scattering problems. As the authors pointed out, this technique is a classical one. However, the authors have overlooked some classic treatments of application of SWE in antenna and scattering problems. The authors reply by discussing the efficiency of the technique, its convergence, and the effects of the ground plane on asymmetrical antenna structures