A Time-compensation TDOA-based Wireless Positioning Method for Multi-level IoT Positioning

Since traditional satellite positioning technology usually has low positioning accuracy in complex environments, such as indoor environments and dense buildings, wireless positioning technology can be used as a complement to satellite positioning technology to meet the positioning accuracy on special scenes. UWB (Ultra Wideband) can be used as a kind of high-precision wireless positioning technology. However, the construction cost of high-precision system represented by UWB positioning system is very expensive. In order to meet the positioning accuracy requirements and reduce the system construction cost, we propose an architecture of multi-level IoT (Internet of Things) positioning system in this paper. The architecture uses different wireless positioning technologies according to different positioning scenarios, which not only meet the accuracy requirements of the positioning scenes, but also effectively reduce the system construction cost. At the same time, to improve the precision of the wireless positioning technology in multi-level IoT positioning system, we also propose an improved time compensation TDOA-based method. The proposed method can effectively resolve the problem that the positioning accuracy will be affected by the device clock offset when the TDOA method is adopted at the high-level in the multi-level positioning system, and can simultaneously improve the positioning accuracy and reduce the power consumption of the positioning tag. Experiment results validate the effectiveness of the proposed method and system.