A Synthetic Aperture Scheme for Integrated Localization and Navigation in Passive IoT

In passive Internet of Things, existing synthetic aperture-based 3D localization methods face many challenges, such as high computational load, a large aperture of a virtual antenna array, and sensitivity to noise. To address these challenges, this paper develops a synthetic aperture scheme for integrated localization and navigation, which implements the localization algorithm with a trajectory generated by the navigation algorithm. The localization problem is formulated by multidimensional scaling, which exploits phase differences involving the spatial information between target tags and a virtual antenna array. The new formulation allows the system to provide an accurate location estimate with a large moving step and sparse virtual antenna array of narrow apertures. The navigation problem is formulated to decrease errors of distance differences. Moreover, a navigation criterion is established to determine the feasibility of a virtual antenna position based on phase measurements, and an efficient navigation algorithm is proposed to find such a feasible point. Extensive numerical results validate our theoretical analysis and the performance of the proposed scheme.