The phased array radar antennas of microwave remote sensing satellites can experience thermal deformation at extreme space temperatures, leading to a negative impact on image quality. This paper proposes a method for monitoring thermal deformation using Fiber Bragg Grating (FBG) sensing and the inverse Finite Element Method (iFEM). This study analyzes how the layout of FBG sensors affects the accuracy of reconstruction. It aims to optimize the topology of the FBG sensor network. Additionally, a strain transfer coefficient correction (STCC) algorithm is proposed to reduce the effect of strain transfer inaccuracies on the reconstruction result measurements. A Carbon Fiber Reinforced Polymer (CFRP) laminate is used as the simulation object for the radar antenna structure, and an experimental system is set up to monitor thermal deformation. The experimental results demonstrate that the maximum root mean square error (RMSE) is 0.038 mm under the temperature variation condition from 30 °C to 110 °C, which represents 5.4% of the maximum thermal deformation. The results indicate that the monitoring method is highly accurate in measuring the thermal deformation of critical structures in remote sensing satellites while in orbit. This method also shows great potential for a wide range of applications.

微波遥感卫星的相控阵雷达天线在极端空间温度下会发生热变形，从而对图像质量产生负面影响。本文提出了一种使用光纤布拉格光栅（FBG）传感和逆有限元法（iFEM）监测热变形的方法。本研究分析了 FBG 传感器的布局如何影响重建的准确性。其目的是优化FBG传感器网络的拓扑。此外，还提出了应变传递系数校正（STCC）算法，以减少应变传递误差对重建结果测量的影响。采用碳纤维增强聚合物（CFRP）层压板作为雷达天线结构的模拟对象，并建立了实验系统来监测热变形。实验结果表明，在30℃到110℃的温度变化条件下，最大均方根误差(RMSE)为0.038mm，代表最大热变形的5.4%。结果表明，该监测方法对在轨遥感卫星关键结构热变形测量具有较高的准确度。该方法还显示出广泛应用的巨大潜力。