An Overview of Cellular ISAC for Low-Altitude UAV: New Opportunities and Challenges

TL;DR

This paper reviews the emerging role of low-altitude UAVs in cellular networks, highlighting their potential for integrated sensing and communication in 3D air-ground networks, along with associated opportunities and challenges.

Contribution

It provides a comprehensive overview of cellular-connected UAV ISAC, focusing on their dual roles and addressing unique 3D network coverage challenges.

Findings

UAVs enable 3D air-ground ISAC networks.

UAVs serve as both sensing targets and network anchors.

New opportunities arise in UAV-assisted 6G networks.

Abstract

Low-altitude unmanned aerial vehicles (UAVs) are expected to play an important role in future wireless networks, either as aerial base stations (BSs) or aerial users connected to the cellular network. In addition, integrated sensing and communication (ISAC) has been identified as one of the six usage scenarios for the forthcoming sixth-generation (6G) mobile networks, aimed at improving network functionalities and realizing situational awareness of the physical world. While most existing research efforts focus on terrestrial two-dimensional (2D) communication and sensing, UAV as an aerial platform offers a new degree of freedom for designing three-dimensional (3D) air-ground (AG) ISAC networks. In this article, we provide an overview of cellular-connected UAV ISAC, by elaborating the UAV's roles as a target to be sensed and as an aerial anchor to provide sensing functionality, respectively. In particular, we pay attention to the network coverage issue and topics specific to UAV networking, emphasizing the new opportunities as well as unique challenges to be addressed.