Comment on ´Numerical check on the accuracy of spherical-wave expansions´

A convergence criterion for the Laurent spherical-wave expansion is discussed, with particular emphasis on its dependence on the nature of the radiating source. Both an inappropriate choice of truncation point of the series and of the integration surface for the determination of the spherical-wave coefficients may introduce errors in near-field antenna calculations. However, a procedure is outlined which ensures that an accuracy of the order of one part in 10⁵ is achieved.