On the deformation monitoring based on integrating InSAR with GPS for expressway/goaf

Integrating InSAR with GPS data, how to monitor and evaluate the influence of goaf on expressway was investigated. To unwrap the sparse phases in the deformation information on expressway as extracted from D-InSAR bands, LAMBDA phase unwrapping algorithm commonly used in GPS is proposed with an appropriate resolving model developed to acquire the deformation time-series for the expressway with goaf from D-InSAR bands so as to keep abreast of new development of the influence of goaf on expressway. While the radar satellite is in transit, the 3rd class leveling is used to measure the deformation to verify the monitoring feasibility of expressway deformation. The experimental results showed that the expressway/goaf deformation monitoring via integrating InSAR with GPS is feasible and reliable and has broad prospects in applications.