Ma Liantao, Zhang Chaohe, Wang Yasha, Peng Guangju, Chen Chao, Zhao Junfeng, Wang Jiangtao
Key Laboratory of High Confidence Software Technologies, Ministry of Education, Beijing 100871, China.
School of Electronics Engineering and Computer Science, Peking University, Beijing 100871, China.
Sensors (Basel). 2020 Mar 12;20(6):1580. doi: 10.3390/s20061580.
GPS is taken as the most prevalent positioning system in practice. However, in urban areas, as the GPS satellite signal could be blocked by buildings, the GPS positioning is not accurate due to multi-path errors. Estimating the negative impact of urban environments on GPS accuracy, that is the GPS environment friendliness (GEF) in this paper, will help to predict the GPS errors in different road segments. It enhances user experiences of location-based services and helps to determine where to deploy auxiliary assistant positioning devices. In this paper, we propose a method of processing and analysing massive historical bus GPS trajectory data to estimate the urban road GEF integrated with the contextual information of roads. First, our approach takes full advantage of the particular feature that bus routes are fixed to improve the performance of map matching. In order to estimate the GEF of all roads fairly and reasonably, the method estimates the GPS positioning error of each bus on the roads that are not covered by its route, by taking POIinformation, tag information of roads, and building layout information into account. Finally, we utilize a weighted estimation strategy to calculate the GEF of each road based on the GPS positioning performance of all buses. Based on one month of GPS trajectory data of 4835 buses within the second ring road in Chengdu, China, we estimate the GEF of 8831 different road segments and verify the rationality of the results by satellite maps, street views, and field tests.
全球定位系统（GPS）在实际应用中被视为最普遍的定位系统。然而，在城市地区，由于GPS卫星信号可能被建筑物遮挡，GPS定位会因多径误差而不准确。评估城市环境对GPS精度的负面影响，即本文中的GPS环境友好性（GEF），将有助于预测不同路段的GPS误差。这能提升基于位置服务的用户体验，并有助于确定辅助定位设备的部署位置。在本文中，我们提出一种处理和分析大量历史公交GPS轨迹数据的方法，以结合道路上下文信息来估计城市道路的GEF。首先，我们的方法充分利用公交线路固定这一特点来提高地图匹配性能。为了公平合理地估计所有道路的GEF，该方法通过考虑兴趣点（POI）信息、道路标签信息和建筑物布局信息，来估计每辆公交车在其线路未覆盖道路上的GPS定位误差。最后，我们利用加权估计策略，根据所有公交车的GPS定位性能来计算每条道路的GEF。基于中国成都二环路内4835辆公交车一个月的GPS轨迹数据，我们估计了8831个不同路段的GEF，并通过卫星地图、街景视图和实地测试验证了结果的合理性。
