Cooperative Localization in Mobile Wireless Networks With Asynchronous Measurements and Communications

This paper studies the cooperative localization problem for mobile nodes. Different from the previous work which highly relies on the synchronized time-slotted systems, the cooperative localization framework we establish does not need any synchronization for the communication links and measurement processes in the entire wireless network. More specifically, the mobility of nodes is modeled by the stochastic differential equation, which allows the modeling of each node utilizing the asynchronously received messages and measurements in the continuous-time domain. To solve the cooperative localization problem, first we propose the centralized localization algorithm based on the global information. Then, we rigorously prove under what condition a localization estimation with partial information has a small performance gap from the one with global information. Finally, by applying this result at each node, the distributed prior-cut algorithm is designed to solve this asynchronous localization problem. Two cooperative localization examples are presented to corroborate the effectiveness of the distributed prior-cut algorithm in dealing with asynchronous communications and measurements.