DATA DOUBLE OVERSAMPLING METHOD, SYSTEM DEVICE AND STORAGE MEDIUM

A data double oversampling method includes: obtaining the initial sampling phase of two adjacent bits of the preamble in a GPON frame and the phase label of each initial sampling phase. Based on whether the adjacent phase labels of the target jump edge before and after shifting are equal and whether the first reference sampling phase is located at the target jump edge, shifting each sampling phase after shift again to obtain the optimal sampling phase corresponding to the two adjacent bits, in order to sample the valid data. The method samples the valid data by determining the optimal sampling phase at the preamble, and can stably complete the phase locking of the recovered data within the time specified in the protocol; and there is no need to change hardware devices which saves costs.