Secret communication method and system based on programmable metasurface

According to the wireless secret communication method based on the programmable metasurface, a system is composed of a sending end and a receiving end, and the sending end comprises a sending sensingunit and an RIS regulation and control unit; the receiving end comprises a receiving processing unit and a mobile node unit; the method comprises the following steps: 1) before data communication between a sending end and a receiving end, an authentication decryption module of the receiving end and an authentication encryption module of the sending end complete identity authentication and communication key Kc negotiation; 2) the sending end encrypts and sends the file information by adopting a communication key Kc, and splits the data according to the condition of mobile communication; 3) a control matrix of a regulation and control module in the RIS regulation and control unit is selected according to the binary data information and the relative position information of the mobile node relative to the metasurface