不同参考框架对区域连续GPS数据解算的影响

INFLUENCE ON RESULTS CALCULATED FOR REGIONAL GPS CONTINUOUS DATA WITH DIFFERENT REFERENCE FRAMES

基于陕西区域GPS连续观测资料及地壳运动观测网络、全球IGS站观测数据,应用不同参考框架进行数据处理,从速度和坐标序列重复率两方面比较不同方案的解算结果。分析表明,在研究区域网站点运动变化时,如选取全球分布站点作为参考框架,所得到的测站坐标和速率比较接近绝对地心基准,但各站准周期的变化被作为误差处理,所以结果的重复性相对较差;选择距研究区域较近的参考站作为平差基准,各点准周期变化部分被相似变换的平移参数吸收,同时抵消了部分区域共模误差,从而提高了结果的自洽性。获取稳定可靠区域形变信息的解算方案为:分级建立稳定参考框架,把区域站逐级纳入到全球框架中。

Regional GPS continuous observation data combined CMONOCGPS data and IGS data were processed with different satellite ephemeris and reference frames,and coordinate series repetition rate and velocity are compared. The results show that,if global distribution sites are selected as a reference frame,the station coordinates and velocity calculated are more close to absolute geocentric datum,however the periodic variation of each station is treated as error in the processing,the coordinate repetition is relatively poor; if the sites near the research region are selected as a reference adjustment datum,the periodic variation is weaken by the similar transform parameters,part of the regional common mode error is eliminated,and the self-consistent of results are improved. A reasonable calculation scheme to get regional deformation information is to build a stable reference frame by adding the regional results into global solutions step by step.