An efficient numerical integral in three-dimensional electromagnetic field computations

When applying moment method solutions to electromagnetic problems, an integration requiring numerical evaluation is usually encountered. A numerically efficient technique for this evaluation is outlined. The technique involves expanding the intergrand in a binomial series for large arguments and in a Taylor series for small arguments. The proposed technique for evaluating the large argument integral has been tested, and it yields an approximately 30% percent reduction of computation time without any loss in accuracy, as compared with techniques currently in common use.<>