Global Navigation Satellite System (GNSS) satellites are relatively far away from GNSS receivers, and the signal-to-noise ratio of satellite navigation signals reaching GNSS receivers is low, and it is not easy for GNSS receivers to estimate the Doppler frequency of navigation signals. On the other hand, the receiver operating in a highly dynamic environment will also lead to low signal-to-noise ratio of the received satellite navigation signal. Therefore, the principles of serial search algorithm, parallel frequency search algorithm and parallel code phase search algorithm and their adaptability under low signal-to-noise ratio conditions are studied, which provide a reference for the design of receiver acquisition algorithm.