Cooperative Group Localization for 4G Wireless Networks

In traditional TOA or TDOA-based cellular localization, if mobile terminal (MT) can not connect well with 3 or more than 3 BSs, the localization will fail, or positioning accuracy is very poor. To solve this problem in 4G wireless networks, the cooperative group localization (CGL) scheme is proposed in this paper, where it is assumed that different MTs can directly communicate with each other in a peer-to-peer manner and perform the distance measurement, forming a terminal group (TG). When each MT in a TG connects with less than 3 BSs, CGL makes it possible to locate all the MTs in the TG by other MTs´ cooperation. The proposed scheme can effectively enhance the robustness and precision of localization. Based on rigid graph theory, the unique solvability of CGL scheme is analyzed in theory. A searching and positioning algorithm for CGL is introduced, and numerical simulations indicate that the proposed algorithm has significantly advantages, compared with traditional localization methods.