软件GPS接收机跟踪阶段的自适应帧选择算法

摘要

With the purpose of improving the initial positioning efficiency of a software GPS receiver, this paper presents an adaptive frame selection algorithm for its tracking period from the angle of practical application.When using the algorithm, an initial section of the navigation data can be preprocessed to determine the ID of frames, and then an appropriate strategy can be formulated to handle the next navigation data.The frames that are not involved in the initial positioning are dropped, therefore, the navigation data that will be processed is reduced significantly.Finally, the initial positioning efficiency is improved to reduce the time to first fix (TTFF).Because this method starts from the original data sources in the tracking loop to reduce the amount of data and computing, it can greatly reduce the TTFF.The experimental results demonstrate this algorithm can improve the initial positioning efficiency and reduce tracking operations significantly.Most importantly, it provides a solid foundation for the real-time embedded platform.%从接收机的实际应用模式出发,以提高接收机初次定位的效率为目的,提出了软件GPS接收机跟踪阶段的一种自适应帧选择算法.该算法通过先跟踪并解调一段导航数据来判断初始帧的帧号,然后制定相应的策略有选择地处理接下来的导航数据,舍弃与初始定位无关的帧,从而大大减少跟踪阶段的数据处理量,提高初次定位效率,缩短冷启动时间(TTFF).该算法是从原始数据源出发来减少跟踪环路的数据处理量,因此能显著缩短TTFF的平均时间.实验结果表明,此算法能有效减少跟踪操作,大幅提高初次定位效率,为后期嵌入式平台上的GPS实时纯软件基带信号处理奠定了基础.