考 虑 吸 波 材 料 的 雷 达 散 射 截 面 伴 随 优 化 方 法

The development of anti-stealth technology has put forward higher requirements for the stealth performance of military aircraft. This study establishes a discrete adjoint equation of Maxwell’s equation considering the absorbing material to perform optimization design of low observable aircraft considering the absorbing material. The fast multilayer multipole expansion form of the adjoint equation is derived，achieving efficient RCS gradient calculation with re⁃ spect to shape parameters，material electrical parameters，and coating thickness. A switch function is proposed to conduct absorbing material coating position optimization. Shape parameters，material coating position，coating thick⁃ ness，and electromagnetic parameters are optimized using the adjoint method. Numerical results indicate that the ad⁃ joint approach can further reduce the cavity RCS compared to the ideal conductor shape design and material coating. Also，the adjoint approach is able to optimize the design of material parameters and coating thickness，providing guid⁃ ance for the selection and coating of the absorbing material. Optimization of the coating position based on the switch function can achieve optimal allocation of the absorbing material with the constraint of total material weight. The pro⁃ posed RCS adjoint optimization method considering the absorbing material can provide technical support for the effi⁃ cient design of coating position and absorbing material coefficients.