Cryosat-2数据的大地水准面分辨能力研究  

Estimation of the Resolution Capability of the Cryosat-2 Altimeter

作　　者：张胜军[1] 金涛勇[1] 褚永海[1] 孔祥雪[1] 

机构地区：[1]武汉大学测绘学院,湖北武汉430079

出　　处：《武汉大学学报（信息科学版）》2016年第6期759-764,共6页Geomatics and Information Science of Wuhan University

基　　金：国家重点基础研究发展计划(2013CB733301);国家自然科学基金(41210006;41304003);国家高技术研究发展计划(2013AA122502);武汉大学地球空间环境与大地测量教育部重点实验室开放基金(15-02-09)~~

摘　　要：Cryosat-2卫星首次提供了369d重复周期的密集漂移轨道测高数据,可用于改进海洋重力场反演精度和分辨率。从信号和噪声两个角度对其沿轨数据进行自回归建模,给出了一种以重复轨道观测序列差分加和确定信号谱和噪声谱,并比较分析测高数据大地水准面分辨能力的方法(称为信噪比分析法)。对全球5个试验区域采用谱关联性法和信噪比法来分析Cryosat-2沿轨数据的大地水准面,其分辨能力约为23~33km,均值约为27km,优于单周期Geosat/ERM、ERS-1/ERM和T/P数据的38km、43km和37km。研究表明,Cryosat-2数据具有更低噪声水平和更高大地水准面信号辨识度,可以为构建海洋重力场模型提供更高分辨率的短波信息。The cryosat-2satellite recently published its first altimeter dataincluding periodically drifting orbit and dense ground tracks.These data can be used to improve the accuracy and resolution of the marine gravity field.In this paper,we constructs auto-regressive models of the altimeter data series by considering two aspects of signal and noise,and propose a new method called the signal-tonoise ratio analytical method for estimating the resolution capability of Cryosat-2data.in five test cases,this new method offers a consistent alternative to the traditional spectral correlation method.The resolution capability of Cryostat-2altimeter data from single cycle is in the range of 23km^33km,with an average value of 27 km,and better than 38 km,43km and 37 km of the Geosat/ERM,ERS-1/ERM and T/P data.This result shows that the Cryosat-2altimeter data has a lower noise level and a higher geoid signal recognition.Therefore,it is reasonable to believe that the Cryostat-2could provide shorter wavelength information for the construction of marine gravity field with higher resolution.

关 键 词：卫星测高 大地水准面 分辨能力 谱关联性 信噪比 

分 类 号：P228[天文地球—大地测量学与测量工程]