天宫二号InIRA数据系统延迟改正估算方法

An estimation method of systemic delay correction for Tiangong-2 InIRA data

高精度和高空间分辨率的宽刈幅3维成像微波高度计(InIRA)在探测海洋和陆地水文变化等方面具有广阔的应用前景。然而,在湖泊水位监测应用中,由于InIRA传感器的系统延迟偏差,导致水位反演出现米级偏差。为此,针对InIRA的数据特性,本文提出了一种以Cryosat-2数据为基准的InIRA系统延迟改正估算方法,该方法在一定区域内可获取较为可靠的系统延迟改正量。利用该方法,在研究区内获取了4.6287 m的系统延迟改正,将该系统延迟改正加入后反演青海湖水位的精度为0.3327 m,表明了系统延迟改正的可靠性,也体现了InIRA数据在湖泊水位反演方面的潜力。

Interferometric image radar altimeter(InIRA)with high-precision,high-resolution and wide-swath has a broad application prospect in detecting marine and terrestrial hydrological changes.However,for lake level estimation,due to the systemic delay of InIRA,the bias of lake level estimation could reach meters level.So in this work,based on the feature of the InIRA data,an estimation method of systemic delay correction for InIRA data using Cryosat-2 data as a reference is proposed.The reliable systemic delay in some areas is obtained through this method,and the systemic delay is corrected to 4.6287 m in the study area.The accuracy of Qinghai Lake level estimation is 0.3327 m when the systemic delay is corrected,indicating the reliability of this systemic delay correction and the potential of estimating lake level using InIRA data.