This article presents the most thorough study to date of vehicular carrier-phase differential Global Navigation Satellite System (CDGNSS) positioning performance in a deep urban setting unaided by complementary sensors. Using data captured during approximately 2 h of driving in and around the dense urban center of Austin, Texas, a CDGNSS system is demonstrated to achieve 17-cm-accurate 3D urban positioning (95% probability) with a solution availability greater than 87%. The results are achieved without the aid of inertial, electro-optical, or odometry sensors. The development and evaluation of the unaided, GNSS-based precise positioning system is a key milestone toward the overall goal of combining precise GNSS, vision, radar, and inertial sensing for all-weather, high-integrity, high-absolute-accuracy positioning for automated and connected vehicles. The system described and evaluated herein is composed of a densely spaced reference network, a software-defined GNSS receiver, and a real-time kinematic (RTK) positioning engine. A performance- sensitivity analysis reveals that navigation data wipeoff for fully modulated GNSS signals and a dense reference network are key to high-performance urban RTK positioning. A comparison with existing unaided systems for urban GNSS processing indicates that the proposed system has significantly greater availability or accuracy.

中文翻译：

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深城区无人精确全球导航卫星系统车辆定位

本文介绍了迄今为止在没有互补传感器的情况下，在城市深处的车载载波相位差分全球导航卫星系统 (CDGNSS) 定位性能的最彻底研究。使用在德克萨斯州奥斯汀密集的城市中心及其周围行驶大约 2 小时期间捕获的数据，CDGNSS 系统被证明可以实现 17 厘米精确的 3D 城市定位（概率为 95%），解决方案可用性大于 87%。无需借助惯性、光电或里程计传感器即可获得结果。基于 GNSS 的独立精确定位系统的开发和评估是朝着将精确 GNSS、视觉、雷达和惯性传感相结合以实现全天候、高完整性、自动和联网车辆的高精度定位。此处描述和评估的系统由密集间隔参考网络、软件定义的 GNSS 接收器和实时动态 (RTK) 定位引擎组成。性能敏感性分析表明，完全调制的 GNSS 信号和密集参考网络的导航数据擦除是高性能城市 RTK 定位的关键。与用于城市 GNSS 处理的现有独立系统的比较表明，提议的系统具有更高的可用性或准确性。性能敏感性分析表明，完全调制的 GNSS 信号和密集参考网络的导航数据擦除是高性能城市 RTK 定位的关键。与用于城市 GNSS 处理的现有独立系统的比较表明，所提议的系统具有明显更高的可用性或准确性。性能敏感性分析表明，完全调制的 GNSS 信号和密集参考网络的导航数据擦除是高性能城市 RTK 定位的关键。与用于城市 GNSS 处理的现有独立系统的比较表明，所提议的系统具有明显更高的可用性或准确性。