E. Yu. Altshuler, A. N. Bushuev, M. V. Davidovich
The method of reducing the Poklington integrated equations for analysis of wire spiral and helix antenna to the Hallen equations is considered. The method is based on replacing of surface integral equation to the linear one concerning a current on an axis of a wire spiral conductor in approach of thin wire antennas. Boundary conditions are imposed on the similar spiral (helix) line belonging to wire surface (or by averaging on several such lines). For the account of tape conductors, it is possible to use multi-filar helixe currents with imposing of boundary conditions on helix lines between them. As the excitation the delta-sources and finite delta-shaped ones are considered. In the specified approach, the method allows one to make the strict full-wave electromagnetic analysis of the considered antennas at current approximation on full basis with the use of projective methods.
Various flat spirals and Cornu pseudo-spiral, and also rectangular spirals are considered, for which the corresponding current approximations are received. The radiation patterns (RPs) of helix are received and calculated. It is shown that for them strong RP dependence on frequency takes place. With frequency growth there are big petals of RP under small corners to longitudinal direction, and azimuthal RPs becomes strongly asymmetrical.