Rapid single point positioning enhancement service and application based on urban CORS

doi:10.11947/j.AGCS.2024.20240077

Abstract

Abstract:

In the realm of smart city development, the scalability, privacy, and heightened reliability of CORS (continuously operating reference station) location services have emerged as pivotal focal points. This paper presents an innovative urban CORS augmented positioning service leveraging PPP-RTK (precise point positioning-real-time kinematic) technology. It delineates the formulaic methodology for achieving enhanced precision single-point positioning within urban environments, elucidating the estimable parameters essential for urban CORS augmented positioning and their practical implementation on client platforms. Through integration with real-time data sourced from the Guangzhou CORS network, the efficacy of the PPP-RTK service is rigorously evaluated. Test results demonstrate that the initial epoch of the PPP-RTK client plane rapidly converges to centimeter-level accuracy, with vertical elevation convergence achieved within approximately seven epochs. Furthermore, the performance of the enhanced positioning parameter SSR2OSR (state space representation to observation space representation) in PPP-RTK is found to be comparable to that of short baseline RTK solutions, thus substantiating its capacity to cater to the monitoring requirements of a substantial user base. On-board experiments exhibit superior 3D accuracy, surpassing lane-level precision by a margin of less than 0.5 meters, underscoring the capability of PPP-RTK positioning to fulfill the stringent reliability criteria essential for various positioning applications.

Key words: CORS, BDS, precise single point positioning, ground enhancement system

CLC Number:

P258

Yang LIU, Guang YANG, Xiaohui CHENG, Xiao ZHANG. Rapid single point positioning enhancement service and application based on urban CORS[J]. Acta Geodaetica et Cartographica Sinica, 2024, 53(9): 1706-1714.

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参数	数学表达式	备注
接收机位置	x_u
接收机钟差
接收机相位偏差
接收机码偏差		j≥1；s≥1
模糊度		j≥1；s≥2
基准(非可估参数)	d_u，1，d_u，2，	j≥1；s≥1

参数	数学表达式	备注
天顶对流层延迟增量	Δτ_v=τ_v－τ₁	r≥1
卫星钟差		s≥1
电离层延迟		r≥1；s≥1
卫星相位偏差		j≥1；s≥1
卫星码偏差		j>2

项目	服务端与用户端
频率	GPS L1&L2、BDS B1I &B3I
观测值	双频码、相位观测值
观测数据采样率/s	15
参数估计策略	Kalman滤波
观测值加权策略	高度角加权
先验观测值精度/m	伪距为0.3，相位为0.003
对流层延迟	UNB3M模型经验改正干、湿分量模型随机游走估计残余对流层湿延迟随机游走过程噪声设置为10^－8 m²/30 s
周跳探测	DIA (detection，identification and adaptation)
相位模糊度	先弧段常数估计，再部分模糊度固定
其他改正	接收机PCO/PCV改正、卫星PCO/PCV改正、相位缠绕、固体潮、海潮、极潮
电离层延迟	服务端白噪声估计、用户端采用产品改正
卫星截止高度角/(°)	10
坐标	服务端先验值改正、用户端白噪声估计

站点	GPS DSTEC			BDS－3 DSTEC
站点	04－22	04－23	04－24	04－22	04－23	04－24
YOHE	0.020	0.016	0.013	0.028	0.011	0.011
XJIE	0.031	0.070	0.028	0.032	0.020	0.020
GDFG	0.025	0.078	0.019	0.030	0.018	0.017
LVTI	0.019	0.033	0.013	0.021	0.015	0.011
YHGT	0.023	0.079	0.018	0.026	0.016	0.013
SPGT	0.014	0.035	0.007	0.017	0.008	0.008
DLSH	0.020	0.058	0.017	0.022	0.012	0.012
ZHGT	0.026	0.077	0.025	0.022	0.013	0.016
ZSGT	0.025	0.042	0.015	0.021	0.012	0.012
HELI	0.025	0.058	0.023	0.024	0.014	0.016
SDGT	0.017	0.026	0.014	0.021	0.012	0.011
SHAT	0.014	0.014	0.010	0.015	0.009	0.008
SHJU	0.018	0.037	0.011	0.019	0.009	0.009
SSGT	0.021	0.022	0.010	0.026	0.011	0.011
HUAD	0.020	0.067	0.020	0.025	0.013	0.014
QYGT	0.021	0.020	0.014	0.025	0.012	0.013
平均	0.021	0.046	0.016	0.023	0.013	0.013

日期	定位误差/cm			TTFF/历元
日期	E	N	U	TTFF/历元
2023－04－21	1.4	1.2	4.1	7
2023－04－22	1.5	1.4	3.6	8
2023－04－23	1.0	0.7	2.6	7
2023－04－24	1.2	0.9	3.8	7
2023－04－26	0.6	0.7	2.9	8
2023－04－28	0.9	0.7	2.5	7
2023－04－29	1.2	1.1	3.4	7
2023－04－30	1.2	1.2	3.0	7