The carrier synchronization algorithm of the autonomous radio for deep space is studied.When the signal modulation is unknown,this paper improves the existing universal carrier synchronization loop for multiple modulations,expands the frequency tracking range of the loop,proposes a Tong detection-based M-ary Phase Shift Keying(M-PSK)signal locking detection algorithm to rapidly and effectively determine whether the current phase discrimination mode matches the modulation mode,so as to independently choose whether to switch the phase discrimination mode.Through theoretical analysis and comparison,it is described that the total detection probability of the algorithm proposed in this paper is significantly higher than the probability of single lock detection.Simulation results show that the algorithm has high detection probabiUty and low computational complexity at a low signal to noise ratio. The carrier synchronization algorithm of the autonomous radio for deep space is studied. Because the signal modulation is unknown, this paper improves the existing universal carrier synchronization loop for multiple modulations, expands the frequency tracking range of the loop. -ary Phase Shift Keying (M-PSK) signal locking detection algorithm to rapidly and preferably determine whether the current phase discrimination mode matches the modulation mode, so as to independently choose whether to switch the phase discrimination mode. Threshold theoretical analysis and comparison, it is described that the total detection probability of the algorithm proposed in this paper is significantly higher than the probability of single lock detection. Simulation results show that the algorithm has high detection probabiUty and low computational complexity at a low signal to noise ratio.