The establishment of the BeiDou global navigation satellite system (BDS-3) has been completed, and the current constellation can independently provide positioning service globally. BDS-3 satellites provide quad-frequency signals, which can benefit the ambiguity resolution (AR) and high-precision positioning. This paper discusses the benefits of quad-frequency observations, including the precision gain of multi-frequency high-precision positioning and the sophisticated choice of extra-wide-lane (EWL) or wide-lane (WL) combinations for instantaneous EWL/WL AR. Additionally, the performance of EWL real-time kinematic (ERTK) positioning that only uses EWL/WL combinations is investigated. The results indicate that the horizontal positioning errors of ERTK positioning using ionosphere-free (IF) EWL observations are approximately 0.5 m for the baseline of 27 km and 1 m for the baseline of 300 km. Furthermore, the positioning errors are reduced to the centimetre level if the IF EWL observations are smoothed by narrow-lane observations for a short period.

中文翻译：

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使用BDS-3四频信号改善了精确定位

北斗全球导航卫星系统（BDS-3）的建立已经完成，目前的星座可以独立提供全球定位服务。BDS-3卫星提供四频信号，这可能有利于歧义分辨率（AR）和高精度定位。本文讨论了四频观测的好处，包括多频高精度定位的精确增益以及瞬时EWL / WL AR的超宽车道（EWL）或宽车道（WL）组合的复杂选择。此外，研究了仅使用EWL / WL组合的EWL实时运动（ERTK）定位的性能。结果表明，使用无电离层（IF）的EWL观测值进行的ERTK定位的水平定位误差约为0。基线27 km为5 m，基线300 km为1 m。此外，如果在短时间内通过窄车道观测对IF EWL观测进行平滑处理，则定位误差可降低至厘米级。