Robust Variable Thickness Design of Airborne Radomes Using 3-D-Interpolation Interval Analysis

This work presents a robust variable thickness design method of airborne radomes to improve the worst case electromagnetic (EM) performance under thickness and material property errors. First, with the inclusion of thickness interpolation, the interval analysis (IA) method with 2-D interpolation of incident angle and polarization angle is extended to the 3-D case. Then, with the error-free boresight error (BSE) and the error-affected transmission loss (TL) interval supremum as objectives, the robust optimization models of variable thickness radomes (VTRs) with or without thickness profile control (TPC) are established. The results of a tangent ogival radome validate the effectiveness of the proposed method. Compared with the conventional VTRs, at the cost of tolerable increase of error-free BSE, the TL interval supremum is improved by 15% and 24%, which also implies potential improvement of BSE robustness. Moreover, the first sidelobe level supremums are also reduced.