Research on the performance and electromagnetic mechanism of radar/infrared compatible stealth materials based on photonic crystals

Traditional stealth materials do not fulfill the requirements of the high absorption rate of radar waves and low emissivity of infrared waves. Further, they cannot escape from multiple detection technologies, considerably threatening weapon safety. Therefore, a stealth material compatible with radar/infrared is designed based on the photonic band gap characteristics of photonic crystals. The radar stealth layer (bottom layer) is a composite material of carbonyl iron/silicon dioxide/epoxy resin, while the infrared stealth layer (top layer) is a one-dimensional photonic crystal structure in which germanium and silicon nitride are alternately and periodically stacked. Through composition optimization and structural adjustment, the effective absorption bandwidth of compatible stealth materials with a reflection loss of less than −10 dB has reached 4.95 GHz, and the average infrared emissivity achieved is 0.1063, indicating good compatible stealth performance. Theoretical analysis proves that the structural design of photonic crystals can produce infrared waves within the range of the photonic band gap, achieving a high transmittance of radar waves and low emissivity of infrared waves. Infrared stealth is achieved without affecting the absorption performance of the radar stealth layer, and the conflict between radar and infrared stealth performance is resolved. The objective of this paper is to aid in promoting the application of photonic crystals in compatible stealth materials as well as the development of stealth technology and in providing design and theoretical basis for related experiments and research.