Design of Electromagnetic Detection System for Underground Cultural Relics Protection Based on Spread Spectrum Coding

Illegal theft of underground cultural relics is currently a difficulty in the field of cultural relics protection. The use of underground theft caves for cultural relics theft is a common form of theft. Traditional underground detection technology is difficult to apply due to the fact that the protected cultural relics are located in densely populated areas such as cities, and the cultural and electromagnetic environment is too complex. This article proposes an electromagnetic detection method based on spread spectrum coding combined with correlation identification to address the above issues. The method uses the good autocorrelation and cross correlation characteristics of spread spectrum coding to remove external interference and achieve the reconstruction of resistivity distribution images of underground thief tunnels. Under the guidance of the theory of spread spectrum encoding detection, an electromagnetic detection system for underground cultural relics protection based on spread spectrum encoding was designed, and detection experiments were conducted in the field for self-digging stolen caves. The detection and inversion image results can reflect the location and distribution of underground stolen caves. The experimental results prove that the electromagnetic detection system for underground cultural relics protection based on spread spectrum coding can be applied to detect underground stolen caves. This study provides a new technical protection method for underground cultural relics protection work, and has important scientific significance for maintaining China’s cultural heritage and strengthening cultural confidence.