The instantaneous kinematic velocity obtained by using a stand-alone global navigation satellite system (GNSS) receiver has attracted increasing attention, and has significant for numerous applications. Using the time difference carrier phase (TDCP) measurements, or the displacements they produced, we propose two real-time instantaneous velocity determination methods based on the moving-window polynomial model. The two methods are called the observation-domain and the coordinate-domain, correspondingly. In the calculation process, the Cholesky update method is utilized to improve numerical efficiency. The proposed methods are a finite impulse in nature, and hence are robust against modeling uncertainties, such as temporal outlying measurements, inaccurate information of noise statistics. Two vehicle-mounted experiments were performed to verify the performance of the coordinate-domain and observation-domain methods. The reference velocities used to evaluate the accuracy of velocity estimates are chosen as GNSS/INS smoothing solution and high-rate RTK solution in these two experiments, respectively. The results show that the coordinate-domain and observation-domain methods were comparable in performance, both better than that of the Nonlinear Tracking Differentiator (NTD) method. Specifically, the improvement in terms of root mean square of the proposed methods, compared with the NTD, can be 29.3–40.3% and 6.25–16.4% in the two experiments, respectively.

中文翻译：

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基于移动窗口多项式建模的GNSS实时瞬时测速

通过使用独立的全球导航卫星系统（GNSS）接收器获得的瞬时运动速度已引起越来越多的关注，并且对于众多应用具有重要意义。利用时差载波相位（TDCP）测量或它们产生的位移，我们提出了两种基于移动窗口多项式模型的实时瞬时速度确定方法。这两种方法分别称为观察域和坐标域。在计算过程中，利用Cholesky更新方法提高了数值效率。所提出的方法本质上是有限的脉冲，因此对于建模不确定性（如时间外在测量，噪声统计信息不准确）具有鲁棒性。进行了两个车载实验，以验证坐标域和观察域方法的性能。在这两个实验中，分别选择用于评估速度估算精度的参考速度作为GNSS / INS平滑解决方案和高速率RTK解决方案。结果表明，坐标域方法和观察域方法在性能上可比，均优于非线性跟踪微分器（NTD）方法。具体而言，在两次实验中，与NTD相比，所提方法的均方根改善分别为29.3–40.3％和6.25–16.4％。在这两个实验中，分别选择用于评估速度估算精度的参考速度作为GNSS / INS平滑解决方案和高速率RTK解决方案。结果表明，坐标域方法和观察域方法在性能上可比，均优于非线性跟踪微分器（NTD）方法。具体而言，在两次实验中，与NTD相比，所提方法的均方根改善分别为29.3–40.3％和6.25–16.4％。在这两个实验中，分别选择用于评估速度估算精度的参考速度作为GNSS / INS平滑解决方案和高速率RTK解决方案。结果表明，坐标域方法和观察域方法在性能上可比，均优于非线性跟踪微分器（NTD）方法。具体而言，在两次实验中，与NTD相比，所提方法的均方根改善分别为29.3–40.3％和6.25–16.4％。