A Cylindrical Equivalent Source-Based Physical Optics Method for Rapid Analysis of Airborne Radomes

The physical optics (PO) method treats the outer surface of airborne radomes in front of antennas as a secondary source region when analyzing the electromagnetic performance. The effective reduction of the secondary source region can significantly improve the computational efficiency, which is helpful for the rapid analysis and design of airborne radomes. In this paper, we present a cylindrical equivalent source-based PO method by introducing an antenna radiation cylinder that can cover the main near-field radiation characteristics of the antenna. The cubic-spline interpolation technique is used to standardize the solution method for the boundary of the cylindrical equivalent source of different antenna-radome systems. The results of a tangent-ogival radome verify the validity of the proposed method. Compared with the conical equivalent source-based PO method, the proposed method improves the efficiency by 71.83%. It can be applied to airborne antenna-radome systems with antenna diameters of 12.14 times of wavelength and above, using 10% as the error threshold.