Mechanical and electric performance of bistable composite laminates with membrane antenna

A design and analysis method of multifunctional composite laminates, merging bistable characteristics and antenna function was presented. Based on nonlinear laminated theory and Rayleigh-Ritz method, the stable geometrical configuration of the bistable hybrid laminate was predicted. The theoretical, finite element analysis and measured stable geometrical configurations agree well with each other. The critical loads and electromagnetic performance of the bistable hybrid laminate were investigated. The influences of lay-ups on the configurations, critical loads and electromagnetic performance of the bistable laminate were studied. The results indicate that the main direction of the antenna is reconfigured about 30° in the vertical plane which can expand the beam steering by changing the two stable state of the hybrid laminate. The lay-ups of the laminate has a great influence on the configurations and reflection coefficient of bistable laminate. When the polyimide film thickness is higher than 0.2 mm, the laminate with surface antenna radiation layer has no bistable characteristics and its center frequency will shift to left about 0.2 GHz.