Continuous variable quantum identity authentication method and system based on coherent state

The invention provides a continuous variable quantum identity authentication method and system based on a coherent state, and the method comprises the steps: setting a user side and an authentication center to share an authentication key K={Ks, Kb}, Ks being an authentication private key, and Kb being an authentication base; preparing a quantum coherent state, and encoding the authentication private key on a regular component of the quantum coherent state; sending the prepared quantum coherent state to an authentication center through an optical fiber channel, and performing quantum homodyne detection by the authentication center according to a shared authentication base to obtain a receiving private key; comparing the receiving private key with the authentication private key, calculating the correlation, and judging the legality of the identity; and after successful authentication, carrying out continuous variable quantum key distribution operation, and updating an authentication key. The method can update a