北斗低成本接收机单频PPP海上定位性能分析

Analysis of single-frequency PPP seaborne positioning performance for BDS low-cost receivers

为评估北斗低成本接收机在海洋动态环境中的定位性能,首先从原始观测方程出发,推导出融合BDS-2和BDS-3的单频精密单点定位模型;其次采用PPK解动态约束位置参数和双向滤波的方法,估计得到观测值无偏后验残差,并基于后验残差分析了低成本接收机和测量型接收机在海上的观测数据质量,最后基于实时和事后精密产品,分析了低成本接收机SF-PPP的定位性能。实验表明:低成本接收机的观测噪声较大,相位和伪距观测噪声为测量型接收机的11.9倍和5.6倍。低成本接收机实时水平和垂直定位精度优于0.3 m和0.5 m,收敛时间优于40 min。置信度为95%时,后处理水平和垂直定位精度为0.219 m和0.430 m。结果表明:低成本接收机在海洋动态环境下定位精度为亚米级,可满足部分高精度海洋应用定位需求。

To evaluate the performance of the low-cost BDS receiver on positioning within the marine environment,this paper first derives a single-frequency precise point positioning(SF-PPP)model combining BDS-2 and BDS-3 from the raw observation equations.Then,through the comparison of the posterior residuals,analyzing the data quality of the dynamic GNSS observations above the sea level for low-cost and geodetic receivers,respectively.Finally,the real-time and post-processing precision products are applied to evaluate the positioning accuracy of the SF-PPP model using a low-cost receiver.The experimental results show that the noise of the carrier-phase and pseudorange observations for a low-cost receiver is more than 11 and 5 times that of the geodetic receiver,whose data quality is significantly poor.The real-time SF-PPP method for the low-cost receiver is less than 0.3 m for the horizontal positioning,0.5 m for the vertical positioning,and 40 min for the convergence time.The accuracy of the post-processing horizontal and vertical positioning up to 0.219 and 0.430 m within 95% confidence intervals,respectively.Therefore,the SF-PPP method using the low-cost receiver can be used to measure the submeter-level positioning,which is available for accurate positioning applications on sea level.