Non-uniform surface current distribution on parallel wire loop antennas using curved patches in the method of moments

The normalised magnitudes of the axial and circumferential surface current components (relative to the local wire axis) on parallel wire loop antennas were investigated, for different operating frequencies and spacing distances. The modelling method employed a two-dimensional electric surface patch integral equation formulation solved by independent piecewise-linear basis function methods in the circumferential and axial directions on the wire surface. The loops are each fed by simple axially directed delta-function excitation sources. The aim was to obtain a deeper understanding of non-uniform current distributions and the way they influence losses; the loss predictions using the presented technique for multiple parallel loop antennas are compared with those from other well-established methods (but only capable of modelling simple configurations) and are shown to be in good agreement. The effects of varying the parameters of the configuration are investigated and discussed.