Application research on Offset Tracking technology in monitoring oflarge surface deformation in coal mine subsidence area

In view of problems of long monitoring cycle, low accuracy of extracted deformation quantity of surface shape existed in traditional coal mining subsidence monitoring methods, Offset Tracking technology was applied to monitoring of large deformation of coal mine subsidence area. Taking Zhangshuanglou Coal Mine as research object, the Offset Tracking technology was used to deal with SAR images of the coal mine subsidence area, two-dimensional deformation figure and the mining deformation information in distance and azimuth direction were obtained by adopting method of cross-correlation factor and over sampling to establish terrain fluctuation and noise offset model, and using the least square method to simulate track offset component. The monitoring results of using the Offset Tracking technology was evaluated with measured data. The results show that the maximum subsidence location and deformation direction of the mining area which monitored by the Offset Tracking technology are consistent with the measured data, and the error is only 1 cm. The results show that the Offset Tracking technology can accurately and effectively monitor the large deformation of coal mine subsidence area, and can provide basis for rational control of coal mine subsidence area.