基于最小搜索超椭球的GNSS模糊度固定及检验方法

为进一步简化GNSS模糊度解算流程,降低计算复杂度,重点提高LAMBDA算法的搜索效率,对模糊度解算作出以下改进:1)模糊度检验采用后验概率检验方法,并对其目标函数进行适当简化;2)把简化后的目标函数嵌入模糊度搜索过程,省去了单独的模糊度检验步骤;3)推导了模糊度空间最小搜索超椭球,把搜索区域限制在该超椭球中,缩小了搜索范围,从而大大降低了搜索复杂度。用三组实测数据实验比较了新方法和传统的LAMBDA方法,结果显示新方法搜索复杂度降低普遍在30%左右,最高可接近60%。理论推导和实验结果均证明了新方法的高效性。

GNSS ambiguity resolution and validation based on minimum search hyper-ellipsoid

In order to simplify the calculation process of GNSS ambiguity resolution,degrade its complexity,and improve the search efficiency of the LAMBDA algorithm,the following aspects of the ambiguity resolution is modified:(1) posterior probability validation method is adopted in ambiguity validation,and its objective function is simplified;(2) this simplified objective function is embedded into the ambiguity search procedure,thus the independent step for testing the ambiguity resolution is eliminated;(3) the minimum search hyper-ellipsoid in the ambiguity space is derived,and the searching area is restricted to within this hyper-ellipsoid,thus the search region is reduced,and corresponding complexity is significantly decreased.Three groups of real observed data are used to compare the traditional LAMBDA method with the new method,and the results show that the computational complexity of the new method is reduced by 30％,sometimes even by 60％,compared with that of the traditional one.Theoretical derivation and experimental results verify the high efficiency of the new method.