High-safety optical access system for reducing PAPR based on selection mapping method

The invention discloses a high-safety optical access system for reducing PAPR based on a selection mapping method, and the system comprises the steps: generating two groups of masking factors at a transmitting end, synthesizing a group of random phase vectors with the length of M * N through the two groups of masking factors, then dividing the random phase vectors into M groups of random phase vectors with the length of N, and extracting each group of OFDM symbols which respectively act on N paths of statistics and are independent according to an SLM algorithm principle, randomly modifying phase information of the OFDM symbols according to corresponding rotating phase vectors, and selecting one path of rotated OFDM symbol with the minimum PAPR value and the corresponding rotating phase vector for transmission. According to the method, the PAPR of the OFDM communication system is reduced by using the selection mapping algorithm (SLM), the encryption of the communication system is ingeniously realized, the comm