Error correcting coding and decoding method suitable for quantum secure direct communication

The invention provides an error correcting coding and decoding method suitable for quantum secure direct communication, and belongs to the technical field of quantum secure direct communication. The method comprises the following steps of firstly, at a receiving end and a sending end, replacing a parity check code constraint in a Tanner representing graph of an LDPC code with quantum random numbersequence constraints in order to obtain a Tanner representing graph of an LDPC-QRS code; at the sending end, coding a sending information sequence by utilizing the Tanner representing graph of the LDPC-QRS code in order to obtain a corresponding sending code word, sending the sending code word to a quantum channel for transmission, and receiving a corresponding receiving code word by the receiving end; and at the receiving end, decoding the receiving code word by utilizing the Tanner representing graph of the LDPC-QRS code in order to obtain a corresponding receiving information sequence. Themethod provided by the invention has excellent error correction performance which is close to a Shannon theoretical limitation, and the reliable transmission of information in a quantum secure directcommunication system can be effectively realized.