Abstract—As the signals of GPS satellites are susceptible to obstructions in an urban environment with many tall buildings around, the number of visible satellites is usually less than four. In the circumstances, the normal positioning method can not be used for positioning calculation. In order to obtain continuous positioning results under three satellites, the series of receiver clock bias (RCB) is considered as one visible satellite in this paper. A combined model for predicting the RCB series based on the theory of time series analysis is presented firstly. And then the model is used to aid the normal positioning method for positioning calculation under the conditions of three satellites. From both static and dynamic experiments, it is shown that the prediction model is fit for predicting the RCB series, and the clock-aided positioning method aiding of the prediction model can implement the function of three-dimensional positioning calculation even if there are only three visible satellites.

Index Terms—Urban environment, Positioning calculation, Receiver clock bias (RCB), Combined prediction model

Yunlong Teng is with the School of Automation Engineering, and Research Institute of Electronic Science and Technology, University of Electronic Science and Technology of China, Chengdu 611731, Sichuan,China (corresponding author, e-mail: tyluestc@ 163.com).
Yibing Shi is with the School of Automation Engineering, University of Electronic Science and Technology of China, Chengdu 61173, Sichuan,China (e-mail: ybshi@uestc.edu.cn).
Zhi Zheng is with the Research Institute of Electronic Science and Technology, University of Electronic Science and Technology of China,Chengdu 611731, Sichuan, China (e-mail: zhengzhi-uestc@sohu.com).

Cite: Yunlong Teng, Yibing Shi, and Zhi Zheng, "The Clock-Aided Method for GPS Receiver Positioning in an Urban Environment," International Journal of Computer and Electrical Engineering vol. 3, no. 3, pp. 389-393, 2011.