[Paper Review] An Overview on Integrated Localization and Communication Towards 6G

Xiao Zhiqiang, Yong Zeng|arXiv (Cornell University)|Jun 2, 2020

Indoor and Outdoor Localization Technologies233 references39 citations

TL;DR

This paper provides a tutorial survey of integrated localization and communication (ILAC) for 6G, detailing how localization and communication inter-play across networks, architectures, and 3D aerial-ground scenarios.

ABSTRACT

While the 5G cellular system is being deployed worldwide, researchers have started the investigation of the 6G mobile communication networks. Although the essential requirements and key usage scenarios of 6G are yet to be defined, it is believed that 6G should be able to provide intelligent and ubiquitous wireless connectivity with Tbps data rate and sub-millisecond latency over 3D network coverage. To achieve such goals, acquiring accurate location information of the mobile terminals is becoming extremely useful, not only for location-based services but also for improving wireless communication performance in various ways such as channel estimation, beam alignment, medium access control, routing, and network optimization. On the other hand, the advancement of communication technologies also brings new opportunities to greatly improve the localization performance, as exemplified by the anticipated centimeter-level localization accuracy in 6G by ultra massive MIMO and mmWave technologies. In this regard, a unified study on integrated localization and communication (ILAC) is necessary to unlock the full potential of wireless networks for the best utilization of network infrastructure and radio resources for dual purposes. While there are extensive literatures on wireless localization or communications separately, the research on ILAC is still in its infancy. Therefore, this article aims to give a tutorial overview on ILAC towards 6G wireless networks. After a holistic survey on wireless localization basics, we present the state-of-the-art results on how wireless localization and communication inter-play with each other in various network layers, together with the main architectures and techniques for localization and communication co-design in current 2D and future 3D networks with aerial-ground integration. Finally, we outline some promising future research directions for ILAC.

Motivation & Objective

• Provide a holistic introduction to wireless localization basics and performance metrics.
• Survey how localization and communication inter-work across network layers for ILAC.
• Discuss enabling technologies and 5G localization recommendations shaping centimeter-level accuracy.
• Present ILAC architectures for 2D and 3D (aerial-ground) networks and outline challenges and future directions.

Proposed method

• Review wireless localization fundamentals including definitions, classifications, and measurement models.
• Summarize 3GPP 5G localization recommendations and enabling technologies toward centimeter-level accuracy.
• Examine location-aided communication and how localization supports channel estimation, beam alignment, routing, and network optimization.
• Propose ILAC architectures and co-design approaches for current 2D and future 3D aerial-ground networks.
• Discuss enabling technologies, challenges, and future research directions for ILAC and SSN (self-sustaining networks).

Experimental results

Research questions

• RQ1 How can localization and communication be co-designed to enhance performance in 6G networks?
• RQ2 What architectures and techniques enable centimeter-level localization in 6G, considering 3D aerial-ground integration?
• RQ3 What are the enabling technologies from 5G that support ILAC and how do they scale to 6G?
• RQ4 What challenges and future directions emerge for ILAC and 3CLS in 3D coverage?
• RQ5 How can ILAC facilitate location-aware network optimization, beam management, and sensing in ultra-dense/millimeter-wave networks?

Key findings

• The paper provides a holistic, tutorial-style overview of ILAC toward 6G, unifying localization and communication perspectives.
• It discusses how wireless localization basics and network architectures interact to enable ILAC across 2D and 3D networks.
• The authors outline enabling technologies (e.g., mmWave, massive MIMO, UDNs) as keys to centimeter-level localization and enhanced ILAC performance.
• Aerial-ground integration and 3D ILAC architectures are proposed as essential directions for ubiquitous wireless coverage.
• The article highlights 3CLS and self-sustaining networks as promising paradigms for joint resource management leveraging localization information.
• Future research directions and challenging aspects for ILAC in 6G are discussed, including privacy, reliability, and integration complexity.