Design method for radar absorbing structures using reliability-based design optimization of the composite material properties

摘要

Functional composites dispersed with nanofillers are used to enhance the characteristics of radar absorbing structures (RAS). In this study, the relative permittivity of the RAS substrate is measured under various environmental conditions of temperature and humidity. The probability distributions of the dielectric materials used for RAS are determined using maximum likelihood estimation based on raw data. With the determined distributions, 10(7) samples are generated and sampling-based reliability-based design optimization (RBDO) for reflection loss of a double slab RAS is performed based on transmission line theory. Two objectives considering absorption properties and bandwidth that represent the performance of the RAS are presented. The results of deterministic optimization (DO) and RBDO are compared considering the failure probability of the application system under operating conditions. Although the total thickness increases slightly, the RBDO provides a significant reduction in the failure probability.