在城市地面沉降监测方面,为获取mm级垂向形变,仍存在诸如垂向误差削弱、基准选取、系统参数对高程形变影响等多项提高精度和可靠性的技术难题。分析了不同基准模型用于形变监测的作用和特征,推导了系统参数对平差结果的影响公式。通过对西安地区布设的GPS地面沉降和地裂缝监测网进行附加系统参数和附有约束条件的网平差进行计算,比较了不同平差方案的结果,得出了有参考价值的结果。
GPS has been widely used in geodetic measuring, retains coordinate system, and monitor global plates movement or regional crust deformation. We analyze and compare the effects of different reference models and systematic parameters on adjustment result. Compared with some schemas of adjusting the Xi'an land subsidence monitor network with systematic parameters and constrains, a lot of valuable findings are concluded.