摘要
全球导航卫星系统(GNSS)的地面反射信号已成为人们关注的遥感方法。对浮冰,大穿透能力和大规模表面覆盖的L波段信号能打开类似累积速率的积雪特征的新局面。文章在理论上研究了来自浮冰的全球定位系统(GPS)信号的反射,导出反射信号模型。结果表明,信号尽管复杂,但对雪面(和交界面)粗糙度和类似累积速率的永久积雪参数有意义。对来自复杂信号的极具价值的信息,导出卫星持续接收期间聚焦在地面区域的过程。从测量原则上应该能分别推导表面和积雪参数。
Earth-reflected Global Navigation Satellite System signals have become an attractive tool for remote sensing. For ice sheets, the large penetration capability and the large-scale surface averaging of the L-band signals could open a new look on firnpack characteristics like accumulation rates. In this paper we investigate theoretically reflections of Global Positioning System signals from ice sheets. We derive a model of the reflection signal. The results show that the signal, though complex, is sensitive to the roughness of the snow surface (and internal interfaces) and to firn parameters like accumulation rates. To extract valuable and concise information from the complex signal, we also derive an example procedure that focuses on particular ground zones during a satellite receiver pass. The results indicate that it should be possible in principle to separately infer surface and firnpack parameters from the measurements.
出处
《全球定位系统》
2005年第4期36-41,47,共7页
Gnss World of China
基金
国家863计划(2002AA639270
2002AA639401)资助
关键词
卫星导航
浮冰
积雪
微波遥感
粗糙度
Navigation satellite
ice sheet
firn
microwave remote sensing
roughness