A radar-infrared compatible stealth surface is designed and analyzed.Without modifying the radar absorbing material(RAM),the design can theoretically achieve radar-infrared compatibility and broadband radar absorption through surface patterns and structures.A transmission-line-based model (TLM) is developed to analyze the radar absorbing performance of the surface.Optimization of the structure geometries is conducted aiming to maximize the-10 dB absorption bandwidth in 2-18 GHz.Surface with optimized structure geometries exhibits a superior absorption bandwidth,more than twice the bandwidth of the original 1.5 mm RAM slab,while maintaining a relatively low infrared emissivity.