摘要
针对4种不同气候条件的地区,分析不同高度角时方位角对斜路径对流层延迟的影响,进而提出一种对流层延迟水平梯度的精化方法。实验表明,该方法可更真实地反映对流层延迟在水平方向的非对称性,有效提高VLBI解算精度,基线可重复度提高约4%,天顶对流层延迟估计精度提高约15%。
Tropospheric delay remains an important source of error. Aiming at four regions with different climatic conditions, this paper analyzes the effects of azimuth on slant tropospheric delay at various elevation angles and then proposes an approach to refine horizontal gradients of this delay. The proposed approach improves solution accuracy of VLBI data efficiently: baseline repeatability is improved by 4%, while improvement is 15% for the accuracy of estimated zenith tropospheric delay.
引文
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