多基线组合求解深空航天器载波相位模糊方法

Resolving Carrier Phase Ambiguity of Deep Space Probe with Combination of Multi-Baseline

针对深空航天器高精度定位需求,提出多基线组合求解载波相位模糊方法,获得比群时延更精确的相时延,极大地提高无线电干涉测量精度。首先建立多基线组合求解载波相位模糊的数学模型,推导该方法对长短基线组合的约束条件。然后利用美国甚长基线阵(VLBA)对本文方法进行仿真校验,结果表明航天器定位精度可以达到纳弧度量级。最后结合我国已有干涉测量网,分析在我国未来深空探测任务中采用多基线组合测量载波相时延的可行性,给出满足方法约束的站址选择建议,可为我国深空导航无线电干涉测量技术的发展和深空测控网的完善提供参考。

Aimed at the demand of high accuracy positioning of deep space probes, combination of multi-baselines is used to resolve the carrier phase ambiguity, thus resulting in more accurate phase delay rather than group delay. Firstly, a mathematical model of this method is established. The procedures of resolving carrier phase ambiguity with a combination of multi-length and multi-orientation baselines are analyzed. Then, simulations with the very long baseline array （VLBA） located in the US are conducted to confirm the validity of the method, which indicates that the accuracy of the spacecraft position can reach nano radian level. Finally, combined with the available interferometry network in China, the feasibility of measuring carrier phase delay by use of our method in future deep space missions is discussed. Some suggestions about the selection of new sites are proposed. It will be of benefit to the development of deep space navigation technique and the improvement of deep space tracking network in China.