Localization as a key enabler of 6G wireless systems: A comprehensive survey and an outlook

Abstract

<p>When fully implemented, sixth generation (6G) wireless systems will constitute intelligent wireless networks that enable not only ubiquitous communication but also high-accuracy localization services. They will be the driving force behind this transformation by introducing a new set of characteristics and service capabilities in which location will coexist with communication while sharing available resources. To that purpose, this survey investigates the envisioned applications and use cases of localization in future 6G wireless systems, while analyzing the impact of the major technology enablers. Afterwards, system models for millimeter wave, terahertz and visible light positioning that take into account both line-of-sight (LOS) and non-LOS channels are presented, while localization key performance indicators are revisited alongside mathematical definitions. Moreover, a detailed review of the state of the art conventional and learningbased localization techniques is conducted. Furthermore, the localization problem is formulated, the wireless system design is considered and the optimization of both is investigated. Finally, insights that arise from the presented analysis are summarized and used to highlight the most important future directions for localization in 6G wireless systems.</p>

Performance Analysis of Multi-Reconfigurable Intelligent Surface-Empowered THz Wireless Systems

“…With the aid of [40, Eq. (8.352/2)], (108) can be written as Finally, with the aid of ( 103) and ( 113), (92) can be written as in (38). This concludes the proof.…”

“…Theorem 3: For the case Alice has no knowledge of the instantaneous characteristics of the Alice-Eve channel, the average secrecy rate can be obtained as in (38), given at the top of the next page.…”

Optical Wireless Communications: Illuminating the Path for Cooper's Law

“…Indoor localization techniques have been receiving increasing interest, with applications that span a broad range of use cases such as indoor navigation, evacuation management, and location-based marketing [340], [341]. However, within indoor settings, the actions of individuals and the positions of objects can have varying levels of impact on the wireless signal.…”

Toward Natively Intelligent Semantic Communications and Networking

“…Among the core requirements is energy efficiency in order to extend the battery of mobile nodes and reduce the drastically increasing energy footprint. Moreover, the various services that are envisioned to be implemented in 6G networks, like extended reality (XR) applications, airborne networks, remote driving and more, are entangled with use-case-specific requirements that must be accounted for [7]. Thus, the requirement to move away from the classic Shannon's theory is ever more demanding [8].…”