摘要
以天津渤海湾围海造田形成的规则人工基础设施为参照物,对长时间序列的FY-3B星250 m空间分辨率数据的几何定位精度误差进行量化,并在此基础上对几何定位精度进行了分析。研究发现,FY-3B星中分辨率卫星数据的几何定位精度存在较大误差,尚未完全达到1个像元或亚像元级的精度水平。纬度方向误差明显大于经度方向误差,纬度方向的几何定位误差整体在-2～-9个像元,经度方向误差基本处于±3个像元的水平。经度方向误差随时间序列的增加,呈偏西向偏东的发展趋势;纬度方向的几何定位整体偏北,且有向北扩大的趋势。在天顶角小于30°的范围内,经度方向误差并不随天顶角的增加而变化,而纬度方向误差随天顶角增加而缩小,且变化幅度在扩大。研究结果有助于改善FY-3B星中分辨率卫星数据的几何定位精度以及研究目前几何定位模型存在的问题。
In this paper, we presented a method for validating and evaluating the geometric accuracy of the FY-3B MERSI based on the time series images. Taking the artificial infrastructures in the Tianjin Bay which were reclaimed land from sea in recent years as the references, we validated the geometric accuracy errors of the time series FY-3B MERSI 250 m images, and then analyzed the geometric accuracy. The results show that there is a large geometric error still existing in the FY-3B MERSI data and the preset goal of the geometric accuracy error at 1 pixel or sub pixel level is not actually achieved. The geometric accuracy error in latitude is much larger than that in longitude. The general geometric accuracy error for latitude is around -2 to -9 pixels, while for longitude it is around ±3 pixels. Along with the time elapsing, the geometric accuracy error for longitude is increasing towards east from west direction, while for the latitude is moving northward and becoming larger. Within the zenith angle range of 30°, no trend shows that the geometric accuracy error for longitude is changing as the increasing of the zenith angle, while the geometric accuracy error for latitude is becoming smaller but with the increasing amplitude as the increasing of the zenith angle. The proposed method is practically useful for investigating the existing problems in the geometric model of FY-3B MERSI.
出处
《地理空间信息》
2019年第5期23-26,I0002,共5页
Geospatial Information
基金
国家重点研发计划资助项目(2016YFA0600301
2016YFA0600302)
国家自然科学基金资助项目(41271429)
欧盟FP7资助项目(SIGMA603719)
关键词
气象卫星
GPS
几何纠正
误差分析
检验和验证
meteorological satellite
GPS
geometric correction
error analysis, calibration and validation
