A novel expansion of the fields near dipole and helical antennas

An asymptotic analysis is performed to obtain the E- and H-fields in the close vicinity of dipole and helical antennas. Although the mathematical procedure requires some involved algebra, the resulting series representation of the fields lends itself to simple numerical calculations. It is shown that the asymptotic E- and H-field values are in very good agreement with both the experimental results and those obtained via numerical integration. Considerable savings in computer time (a reduction by a factor of 8-10) is achieved when the asymptotic expressions are used instead of the usual integration methods.