Abstract: By introducing the coding gain to synchronization loop, the code aided iterative synchronization algorithm can achieve the carrier synchronization under low signal to noise (SNR) ratio values. Aiming at the problem of small parameters estimation range in the above algorithms, this paper proposes an iterative carrier synchronization algorithm based on optimization search. By analyzing the relation between carrier offset and soft decoding information, the proposed algorithm obtains a simpler evaluation function. Then, the uniform search way is combined with the modified Powell algorithm to get the optimized estimate of synchronization parameters. Thus, the accurate carrier recovery can be achieved. The simulation results demonstrate that, under low SNR, the proposed algorithm can compensate carrier offset efficiently and has larger synchronization range. Moreover, the perfect synchronization can be approximated after several iterations.