Modelling of Coil-loaded Wire Antenna Using Composite Multiple Domain Basis Functions

The paper discusses aspects of a novel impedance matrix compressing technique and applies the technique to a coil-loaded monopole. The technique can reduce the number of variables required for modeling of structures with curvatures and structures with electrically small features. The reduction in the number of unknowns is accomplished by a logical aggregation/grouping of the individual wire segments into equivalent continuous wires. A single composite basis function is applied over several wire segments. This decouples the number of unknowns from the number of geometrical segments. Aggregation of small features aims a reduction in the impedance matrix’s condition number. The example of coil-loaded antenna has shown that the proposed novel algorithm achieves better accuracy with fewer unknowns than the traditional formulation of the method of moments.