利用GAMIT软件处理了2005年9月、2006年1月和2月每天17个IGS国际GNSS服务(International GNSS Service,IGS)站的GPS观测数据,获得了地球自转参数(Earth rotation parameter,ERP)和日长变化(ΔLOD),并与IGS综合解进行了对比。利用OCCAM 6.2软件处理了相同时间内的甚长基线干涉测量(very long baseline interferometry,VLBI)观测数据,将解算结果与国际VLBI服务(International VLBI Service,IVS)结果进行了对比。分别采用基于内符合精度和IERS 08C04序列的定权方法对VLBI解算结果与GPS解算结果进行了加权平均,获得了VLBI和GPS技术对ERP和ΔLOD的协议结果。研究结果表明,VLBI解算结果与采用的插值方法有较大的关系,基于IERS 08C04序列的加权平均方法达到了利用VLBI解算结果对GPS解算结果进行修正的目的。VLBI和GPS技术的联合弥补了VLBI观测数据密度不够和GPS解算结果不稳定的缺陷,使解算结果的稳定性和可靠性有所提高。
The Earth rotation parameters(ERP)and the variation of length of day(ΔLOD)are estimated by processing the seventeen IGS stations' data collected in September 2005,January and February 2006 with GAMIT,the estimated results of which are compared with the IGS solutions.Secondly,the ERP and theΔLOD are estimated by processing VLBI data during the same period with OCCAM 6.2,the results of which are compared with the IVS solutions.Thirdly,the results of GPS and VLBI are combined in a weighted way,based on their internal accord accuracy and IERS 08C04 respectively.Finally,the conclusion not only shows that the interpolation methods have a significant impact on the VLBI results,but also shows that the combining of VLBI and GPS in the second way can improve the stability and reliability of ERP andΔLOD,which can make up for the shortcoming of the single technique as VLBI or GPS.