基于北斗CORS的铁路快速静态测量方法研究

Research on Fast Static Measurement Method of Railway Based on BDS-CORS

复杂环境下由于卫星信号质量差等原因,常规地区的测量技术标准不具有适用性。为研究复杂环境下快速静态测量的技术方案,利用某铁路带状稀疏卫星导航定位基准站(Continuously Operating Reference Stations,CORS)综合服务系统,开展一系列快速静态测量实验,通过箱形图等方式,分析不同星座、不同观测时长下的测量精度。与铁路控制网的成果比较后发现,观测时长为5~25min且解算成功的前提下,基于CORS的GPS+BDS、单GPS与单BDS的快速静态测量成果计算的外符合精度差异较小,平面和高程中误差整体优于16 mm和45 mm,均可满足像控点测量精度要求;存在解算失败的情况,解算失败的像控点与其距CORS站的距离无显著联系,随着观测时长的增加,解算失败的时段数明显减少。此外,在相同观测时长下,基于CORS的GPS+BDS与单BDS模式测量精度较高,单GPS相对较差。对于复杂环境,北斗CORS系统在铁路快速静态测量方面替代GPS是可行的,建议快速静态测量时长在25 min以上为宜。

Due to the poor quality of satellite signals in complex areas,the measurement technical standards in conventional areas are not applicable.In order to study the technical scheme of fast static measurement technology in complex environment,a series of measurement experiments were carried out by using the railway banded sparse Continuously Operating Reference Stations,and the measurement accuracy under different satellite systems and different observation duration was analyzed by using box plots and other methods.Compared with the results of railway control network,it is found that when the observation during 5 to 25 min and the solution is successful,there is little difference in the outer coincidence accuracy calculated by the fast static measurement results of GPS+BDS,GPS and BDS based CORS.The overall error in horizontal and vertical is better than 16 and 45 mm,which can meet the accuracy requirements of image control measurement.There is a case of solution failure,while the image control point which fails to solve has no significant relationship with its distance from the CORS station.With the increase of the observation time,the number of failure periods of solution decreases obviously.In addition,at the same observation time,GPS+BDS and BDS based on CORS have higher measurement accuracy,while GPS is relatively poor.For complex areas,it is feasible for the BDS-CORS system to replace GPS in the fast static measurement of railways.It is recommended that the duration of fast static measurement should bemore than 25 minutes.