深空通信中高动态多普勒的联合检测算法

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.

Joint-Detection Algorithm for High Dynamic Doppler in Deep-Space Communications

Under low signal-to-noise ratio in deep-space communications, a joint-detection algorithm was developed for the high dynamic Doppler-shift. This algorithm uses three combination periods to narrow the search range, increasing the acquisition probability for Doppler-shift. To obtain the increase of acquisition probability in a closed-form expression, the impact of search range on acquisition probability was studied. Analysis and its simulation show that this algorithm can efficiently increase the acquisition probability and decrease the acquisition bias under the very low signal-to-noise ratio and high dynamic Doppler-shift.