Study on the Electromagnetic Performance of Radome with Laminar Ablation for Reentry Applications

High-temperature ablation leads to variations in the thickness of the radome during high-speed reentry, consequently impacting the overall performance of the antenna-radome system. This paper develops models of laminar ablation shapes for a typical sphere-cone radome on reentry vehicles caused by laminar ablation during reentry. The main electromagnetic (EM) performance of the radome under different ablation states, including boresight error (BSE) and transmission loss (TL), was calculated using the time-domain finite integration method. The findings indicated that ablation causes significant variations in EM performance. Specifically, BSE exhibits significant fluctuations due to changes in the ablation thickness of the spherical nose, while TL experiences a sharp increase with a higher thickness of conical part ablation. We have redefined the asymmetry of insertion phase shift (IPD), taking into account the influence of the antenna and offering more comprehensive insights on the cause of BSE by conducting analysis on the IPD distribution. This work contributes to the prediction of the EM performance of radomes with laminar ablation during reentry and provides guidance for subsequent compensation measures.