基于格论的GNSS模糊度解算

GNSS Ambiguity Resolution Using the Lattice Theory

快速、准确地解算整周模糊度是实现GNSS载波相位实时高精度定位的关键,由于模糊度之间的强相关,基于整数最小二乘估计准则时,需要较长的时间才能搜索出最优的整周模糊度向量。为了提高模糊度的搜索效率,本文在扼要介绍格论的理论框架基础上,引入基于格论的模糊度解算方法,通过格基规约来降低模糊度之间的相关性,从而快速搜索出最优的整数模糊度向量。与此同时,将GNSS领域的主要降相关方法统一到格论框架下,探讨了并建议采用Boot-strapping成功率作为格基规约的性能指标之一。最后试验分析三频多系统长基线相对定位情况下,不同格基规约可获得的性能。

Fast and reliable ambiguity resolution plays a critical role in GNSS real-time precise positioning, however, the computational complexity of finding the optimal integer ambiguity vector directly will be high, because there is strong correction between ambiguities. Thus the lattice theory was introduced in this paper to reduce the correlation for improving the computational efficiency of ambiguity resolution, and the main decorrelation methods currently existed were also analyzed and transformed into the methods of lattice reduction. Then the Bootstrapping success rate was suggested and tested by an experiment to show the performance of these decorrelation methods used for long-baseline ambiguity resolution with multi-frequency GNSS signals.