Semidefinite Programming Algorithms for 3-D AOA-Based Hybrid Localization

By taking different kinds of measurements at the same time, it may be possible to improve the accuracy of target localization or reduce the number of sensors needed. Time-of-arrival (TOA), time-difference-of-arrival (TDOA), time delay (TD), received signal strength (RSS), and angle-of-arrival (AOA) are the commonly used measurements in wireless localization systems. This article first presents a new weighted least squares (WLS) algorithm for the AOA-only localization problem. Then, a unified solution based on semidefinite programming (SDP) is developed for hybrid AOA/TOA, hybrid AOA/TDOA, hybrid AOA/TD, and hybrid AOA/RSS localization problems. Additionally, thorough simulation results show that the proposed SDP algorithms perform better than state-of-the-art techniques.