Abstract

The demand for high-precision positioning has risen substantially in modern urban settings. In that regard, Global Navigation Satellite Systems (GNSS) offer several advantages such as global coverage, real-time capability, high accuracy, ease of use, and cost-effectiveness. The accuracy of GNSS-based positioning, however, suffers in urban environments due to signal blockage, reflection, and diffraction, which makes it difficult to fix ambiguities correctly within a real-time kinematic (RTK). To address this issue, this paper applies random sample consensus (RANSAC) to develop a novel single-epoch triple-frequency RTK positioning method. In our proposed method, the ambiguities of the extra-wide-lane, wide-lane, and original frequencies are resolved sequentially. RANSAC then detects and excludes incorrectly fixed ambiguities. To validate the effectiveness of the proposed method, two static experiments (cases 1 and 2) and one dynamic experiment (case 3) were conducted in representative urban areas. The findings demonstrate that the proposed method outperforms all comparative methods in positional availability, with comparable positional accuracy in terms of root-mean-square errors (RMSEs). In cases 1, 2, and 3, the proposed method achieves 3D RMSEs of 2.74, 4.29, and 20.35 cm, and the positional availabilities of 100%, 75.0%, and 73.1%, using a 10-degree mask angle (and a carrier-to-noise ratio (C/N₀) threshold 35 dB-Hz). The corresponding RMSEs (positional availabilities) of comparative methods are from 1.51 to 4.04 cm (75.7 to 96.3%) in case 1, 4.19 to 7.78 cm (34.5 to 49.9%) in case 2, and 23.52 to 37.54 cm (15.4 to 33.9%) in case 3, respectively. Compared to these methods, the proposed method shows improvements of positional availabilities between 3.7 and 24.3 percentage points in case 1, between 25.1 and 40.5 percentage points in case 2, and between 39.2 and 57.7 percentage points in case 3.

中文翻译：

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基于RANSAC的城市GNSS三频信号瞬时实时运动定位

摘要

现代城市环境对高精度定位的需求大幅上升。在这方面，全球导航卫星系统（GNSS）具有全球覆盖、实时能力、高精度、易用性和成本效益等优势。然而，由于信号阻塞、反射和衍射，基于 GNSS 的定位精度在城市环境中会受到影响，这使得在实时动态 (RTK) 中正确修正模糊度变得困难。为了解决这个问题，本文应用随机样本一致性（RANSAC）开发了一种新颖的单历元三频RTK定位方法。在我们提出的方法中，超宽通道、宽通道和原始频率的模糊度被顺序解决。然后，RANSAC 检测并排除错误修复的歧义。为了验证所提方法的有效性，在代表性城市地区进行了两项静态实验（案例1和2）和一项动态实验（案例3）。研究结果表明，所提出的方法在位置可用性方面优于所有比较方法，在均方根误差（RMSE）方面具有可比的位置精度。在情况 1、2 和 3 中，所提出的方法使用 10 度掩模角（和载体）实现了 2.74、4.29 和 20.35 cm 的 3D RMSE，以及 100%、75.0% 和 73.1% 的位置可用性-噪声比（C / N ₀）阈值35 dB-Hz）。比较方法相应的 RMSE（位置可用性）在案例 1 中为 1.51 至 4.04 cm（75.7 至 96.3%），在案例 2 中为 4.19 至 7.78 cm（34.5 至 49.9%），以及 23.52 至 37.54 cm（15.4 至 33.9%） ）分别在情况 3 中。与这些方法相比，所提出的方法显示，案例 1 的位置可用性提高了 3.7 到 24.3 个百分点，案例 2 提高了 25.1 到 40.5 个百分点，案例 3 提高了 39.2 到 57.7 个百分点。