基于多尺度球面小波解算GPS应变场的方法及应用

提出了利用多尺度球面小波解算GPS应变场的方法,该方法通过建立不规则分布的小波基函数以凸显测站非均匀分布的特征,获取不同空间尺度的应变场.通过对模拟数据进行对比分析验证该方法的有效性,模拟结果显示,多尺度球面小波应变计算方法稳健性较好.在位移场中加入高斯随机误差(均值为0.0mm,标准差为0.5mm)对应变计算结果的影响可忽略不计.从原有位移场随机抽取的60%的数据解算应变场时,仍然能够获取比较可靠的结果,但如果出现大范围的数据空缺,则会对应变结果产生明显影响.基于华北地区GPS测站原始观测数据,通过高精度数据处理方法解算了该区域GPS速度场,根据多尺度球面小波方法,解算了该区域的应变率场及其误差,并分析了其空间分布特征.

Methodology and application of GPS strain field estimation based on multi-scale spherical wavelet

A methodology was proposed to estimate spherical GPS strain based on multi-scale spherical wavelet. By constructing an irregular distribution of wavelet basis functions to highlight non-uniform distribution of stations, this methodology can be used to calculate the strain fields at different spatial scales. The methodology is verified and evaluated using synthetic displacements. The simulated results show that the proposed methodology is robust. If Gaussian errors, with a mean value of 0.0 mm and a standard deviation of 0.5 mm are introduced into displacements, its effect to derived strain field is negligible. If 60% data are extracted from the original displacement field to calculate its strains, the obtained strain field is still reliable. Nonetheless, if large scale of data is missed, it will bring noticeable effect to the derived strain field. Based on the GPS raw data in North China, we obtain a displacement field utilizing a precise data processing strategy. Subsequently, we calculate strain rate field and its associated uncertainty, which spatial characteristics are finally analyzed.