Cross-Correlation Based Spreading Code Authentication Scheme for Civil GNSS Signals

Navigation signal authentication schemes are effective methods to protect civilian receivers against spoofing attacks by providing unforgeable information to verify the authenticity of signals. In this paper Cross-Correlation based Spreading Code Authentication, or CC-SCA, is proposed to authenticate GNSS civilian signals at high time resolution with small storage requirement. CC-SCA employs a cryptographically generated authentication spreading code punctured into public spreading code in civilian signals. Since initial code phases of authentication spreading code are different and derived from security code, a correlation peak can be detected and authenticated in the cross-correlation between baseband signals of different satellites. According to this principle, signal structure and authenticable receiver architecture are proposed while performance metrics and the selection of parameters are analysed. Finally, this scheme is demonstrated with a specific implementation and parameter selection for Beidou B1C civilian signals.