针对深空通信中的低信噪比环境,提出了一种高动态多普勒频偏捕获的联合检测算法.利用3个码元累积周期来缩小搜索范围,从而提高多普勒频偏的捕获概率.为了得到捕获概率增量的闭式表达式,研究了搜索范围对捕获概率的影响.理论分析和仿真结果表明,在同时存在极低信噪比和高动态多普勒频偏的条件下,该算法能有效地提高捕获概率和减小捕获误差. Aiming at the low signal-to-noise ratio (SNR) environment in deep space communication, a joint detection algorithm based on high dynamic Doppler frequency offset acquisition is proposed. By using three symbol accumulation periods to narrow the search range, Doppler frequency offset acquisition Probability.In order to get the closed expression of the capture probability increment, the influence of the search range on the acquisition probability is studied.Theoretical analysis and simulation results show that under the conditions of simultaneous existence of very low signal-to-noise ratio and high dynamic Doppler shift , The algorithm can effectively improve the capture probability and reduce the capture error.