Information Authentication Based Beidou ? Civil Signal Anti-Spoofing Method

BeiDou II satellite navigation system faces serious security threats and is vulnerable to the spoofing attacks,owning to the lack of authentication measures.Under the spoofing attack,the receiver's positioning result will be controlled by the spoofer.Therefore,for ships or aircraft using satellite navigation systems,spoofing attacks will lead to an extremely bad consequence.According to the analysis of spoofing attacks,an anti-spoofing method based on domestic cryptographic algorithm is proposed.All the authentication information are inserted into the reserved bits of the navigation message to realize the information authentication function while avoiding the adjustment of the existing frame structure of BeiDou II satellite navigation system.The authenticity and continuity of satellite time information are verified by the authentication code information.The signature information is used to verify the integrity of satellite position information and other information.In order to avoid authentication failure caused by public key error or key error,key prompt information and public key prompt information are designed to remind the receiver to update the key or the public key.In addition,the public key update method based on digital certificate or BeiDou short message is designed,which ensures the security and reliability of the public key in the update process.In the designed simulation platform of BeiDou II anti-spoofing attack,the experiment of detecting spoofing attacks under guass noise environment was carried out.The experiment results show that the proposed method can detect spoofing attacks and the authentication delay is lower than one percent of the transmission delay,which satisfies the requirements of BeiDou II navigation civil system information authentication,and enhances the ability of BeiDou II civilian signal to resist spoofing attacks.