坐标基准的维持不仅要求有高精度的连续大地测量观测或定期复测,还要求采用合理的数据处理原则与方法。分析了不同平差方法对基准的影响,其中包括经典整体平差、序贯平差和自适应序贯平差。利用GPS监测网数据进行了计算与分析,结果表明,当个别点位发生异常移动或变形时,序贯平差会使坐标基准产生实际的扭曲,而自适应序贯平差则能有效控制异常点位对平差基准的影响,保证了坐标基准的可靠性和现势性。
Renew and maintain of the geodetic coordinate system need not only the continuous monitoring or repeated measuring, but also the reasonable data processing principle and method. The influences of different adiustment methods, including classical adjustment, sequential adjustment and adaptive sequential adjustment, on the datum or the coordinate system are analyzed, a GPS monitoring network is employed to analyze the datum changes due to applying the different adjustment principles. It is shown that sequential adjustment will distort the datum when some of the prior positions have significant deformation. The adaptive sequential adjustment, however, controls the influences of the outliers existing the prior coordinates, thus keeps the datum reliable and reflecting the present position.