Multi‐Objective Optimization Design of Dual‐Polarized Broadband Frequency Selective Rasorber

ABSTRACT To address the challenges of prolonged design cycles, low efficiency, and excessive dependence on specialized expertise in the design of frequency selective rasorber (FSR), this letter presents a novel dual‐polarized broadband FSR design based on multi‐objective optimization algorithm. The proposed approach incorporates a surface patch discretization topology optimization method into two‐dimensional FSR structural design. The discretized surface patches are encoded using a binary representation system and subsequently integrated with structural parameters into an intelligent optimization algorithm for topological configuration enhancement. To resolve the inherent conflict between structural dimensions and design principles in the “Absorption‐Transmission”(“A‐T”) type FSR, while simultaneously addressing the complex surface structure of lossy layers, we design a high‐impedance resistive film‐loaded dense metal patch coding structure combined with a second‐order bandpass frequency selective surface (FSS). For effective optimization of the multi‐variable, multi‐objective FSR design problem, we implemented the NSGA‐II enhanced with a simulated binary crossover operator (SBX) and an improved adaptive mutation mechanism. The optimized “A‐T” type FSR demonstrates exceptional performance, achieving insertion loss less than 3 dB in the 6.88–12.94 GHz range and absorptivity exceeding 80% in the 2.18–6.14 GHz range.