北斗三号新信号中长基线RTK定位研究

Research on Medium-Long Baseline RTK Positioning of BDS-3 New Signal

针对北斗三号MEO卫星和IGSO卫星新增加的B1C和B2a信号中长基线RTK定位精度仍未确定的问题,利用4组中长基线实测数据对BDS-3新信号、BDS-3的B1I、B3I信号和GPS的L1、L2信号进行数据质量分析和中长基线双频RTK定位研究。结果表明,在数据质量方面,BDS-3的可视卫星数和PDOP值优于GPS,BDS-3新信号的信噪比和多路径误差与BDS-3的B1I、B3I信号和GPS的L1、L2信号相当;在中长基线RTK定位方面,BDS-3新信号B1C+B2a组合的模糊度首次固定时间优于BDS-3的B1I+B3I组合,BDS-3新信号B1C+B2a组合的定位精度略优于BDS-3的B1I+B3I组合和GPS的L1+L2组合,可为用户提供cm级定位精度。

The positioning accuracy of medium-long baseline RTK has not been determined in the newly added B1 C and B2 a signals of BDS-3 MEO satellite and IGSO satellite, so to resolve this problem we analyze the data quality of new signals of BDS-3, B1 I and B3 I signals of BDS-3 and L1 and L2 signals of GPS. We further study the positioning of dual-frequency RTK using four groups of measured data of medium-long baseline. The results show that, in terms of data quality, the number of visible satellites and PDOP of BDS-3 are better than GPS, and the SNR ratio and multipath error of new signals of BDS-3 are equivalent to B11 and B3 I signals of BDS-3 and L1 and L2 signals of GPS. In RTK positioning of medium-long baseline, the ambiguity of the new signal B1 C+B2 a combination of BDS-3 is better than B1 I+B3 I combination of BDS-3 for the first time, and the positioning accuracy of new signal combination is slightly better than B1 I+B3 I combination of BDS-3 and L1+L2 combination of GPS. This can provide users with centimeter-level positioning accuracy.