Analysis of aircraft-mounted antennas using modified current-based hybrid technique

In this paper, a modified current-based hybrid algorithm has been proposed for analyzing wire antennas mounted on aircraft fuselage. A slightly large MoM region is chosen so that the currents on antennas and their surroundings can be determined accurately. Only significant interaction between the currents in the MoM and HF regions is considered in an attempt to maintain higher computational efficiency of the proposed method for solving electrically large problems. Special algorithm is employed for identifying lit region on the aircraft. Combined wire and surface integral equations are applied in the MoM region, with the unknown currents being expanded by three types of triangular basis functions. In the HF region, the PO currents are obtained through the PO approximation and can be expressed in terms of the basis functions that are acting as sources for the PO currents. Directive gain patterns of a monopole mounted on a realistic aircraft model have been calculated. Quite good agreement between the simulated results and those obtained using the full wave method (P-FFT method) is observed.