Underground joint localization method based on electromagnetic wave and ultrasonic

For low localization precision of existing underground personnel localization technologies, an underground joint localization method based on electromagnetic wave and ultrasonic was proposed by analyzing ranging principle of electromagnetic wave and ultrasonic wave as well as application characteristics in underground tunnels. In the method, a ratio of distance between a mobile node and two anchor nodes is obtained by approximate calculation according to logarithmic normal distribution model. Vertical coordinate of the mobile node is obtained by electromagnetic wave ranging method, and horizontal coordinate is gotten by ultrasonic wave ranging method. The Matlab simulation result verifies feasibility and localization precision of the method.