Global Navigation Satellite System raw measurements from Android smart devices make accurate positioning possible with advanced techniques, e.g., precise point positioning (PPP). To achieve the sub-meter-level positioning accuracy with low-cost smart devices, the PPP algorithm developed for geodetic receivers is adapted and an approach named Smart-PPP is proposed in this contribution. In Smart-PPP, the uncombined PPP model is applied for the unified processing of single- and dual-frequency measurements from tracked satellites. The receiver clock terms are parameterized independently for the code and carrier phase measurements of each tracking signal for handling the inconsistency between the code and carrier phases measured by smart devices. The ionospheric pseudo-observations are adopted to provide absolute constraints on the estimation of slant ionospheric delays and to strengthen the uncombined PPP model. A modified stochastic model is employed to weight code and carrier phase measurements by considering the high correlation between the measurement errors and the signal strengths for smart devices. Additionally, an application software based on the Android platform is developed for realizing Smart-PPP in smart devices. The positioning performance of Smart-PPP is validated in both static and kinematic cases. Results show that the positioning errors of Smart-PPP solutions can converge to below 1.0 m within a few minutes in static mode and the converged solutions can achieve an accuracy of about 0.2 m of root mean square (RMS) both for the east, north and up components. For the kinematic test, the RMS values of Smart-PPP positioning errors are 0.65, 0.54 and 1.09 m in the east, north and up components, respectively. Static and kinematic tests both show that the Smart-PPP solutions outperform the internal results provided by the experimental smart devices.

来自Android智能设备的全球导航卫星系统原始测量值可以通过先进技术（例如精确点定位（PPP））进行精确定位。为了使用低成本智能设备实现亚米级定位精度，对为大地测量接收机开发的PPP算法进行了调整，并为此提出了一种名为Smart-PPP的方法。在Smart-PPP中，未组合的PPP模型用于跟踪卫星的单频和双频测量的统一处理。为每个跟踪信号的代码和载波相位测量独立设置参数接收器时钟项，以处理智能设备测量的代码和载波相位之间的不一致。采用电离层伪观测为估计斜向电离层延迟提供了绝对约束，并加强了非组合的PPP模型。通过考虑智能设备的测量误差与信号强度之间的高度相关性，将修改后的随机模型用于权重编码和载波相位测量。此外，还开发了基于Android平台的应用程序软件，以在智能设备中实现Smart-PPP。Smart-PPP的定位性能在静态和运动情况下均得到验证。结果表明，Smart-PPP解决方案的定位误差在静态模式下可在几分钟之内收敛到1.0 m以下，并且该收敛的解决方案对于东，北和北半球的均方根（RMS）都能达到约0.2 m的精度。组件。对于运动学测试，在东部，北部和上部，Smart-PPP定位误差的RMS值分别为0.65、0.54和1.09 m。静态和运动学测试均表明，Smart-PPP解决方案的性能优于实验智能设备提供的内部结果。