Satellite altimetry data has become essential for studying the dynamics of water bodies, especially in regions with limited or inaccessible data. Traditional low-resolution mode (LRM) satellites' accuracy cannot be guaranteed when it comes to assessing water levels in small- (< 200 m in width) and medium-sized (200–800 m in width) rivers. Synthetic aperture radar (SAR) altimeters, exemplified by Sentinel-3 A, have shown great potential for inland water altimetry. Nevertheless, developing algorithms to retrack the raw data remains an essential requirement in this context. This is attributed to the width of small-sized rivers, which is often narrower than the along-track resolution of both LRM and SAR altimeters. In addition, new altimeters may have long revisit cycles and different spatial coverage and cannot yield historical data necessary in some situations.

中文翻译：

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改善中小型河流的水位监测：基于增强足迹过滤器的条件阈值重新跟踪器方法


卫星测高数据对于研究水体动态至关重要，特别是在数据有限或无法获取的地区。传统的低分辨率模式（LRM）卫星在评估小型（<宽200 m）和中型（宽200-800 m）河流水位时，精度无法保证。以 Sentinel-3 A 为代表的合成孔径雷达 (SAR) 高度计在内陆水域测高方面显示出巨大的潜力。尽管如此，开发算法来重新跟踪原始数据仍然是这种情况下的基本要求。这是由于小型河流的宽度通常比 LRM 和 SAR 高度计的沿程分辨率更窄。此外，新的高度计可能具有较长的重访周期和不同的空间覆盖范围，并且在某些情况下无法产生必要的历史数据。