Clutter-Resilient ISAC for Low-Altitude Wireless Networks: A 5G Base Station-Compatible Protocol, Waveform, and Prototype

TL;DR

This paper presents a novel ISAC protocol, waveform, and prototype for low-altitude wireless networks that enhances UAV detection and tracking using 5G base stations, achieving high accuracy with minimal impact on existing services.

Contribution

It introduces a clutter-resilient ISAC framework compatible with 5G base stations, including waveform design and prototype implementation for improved UAV sensing.

Findings

Effective tracking of weak, slow UAVs over 1 km

Minimal 1.2% downlink rate loss

Outperforms existing methods in clutter environments

Abstract

Integrated sensing and communications (ISAC) has been envisioned as a promising solution to support emerging services in low-altitude wireless networks (LAWNs), where upgrading 5G ground base stations (GBS) toward new active sensing systems with wide coverage, low cost, high accuracy, and favorable spectrum compatibility, is strongly desired. However, such an evolution faces several critical challenges, particularly in the detection and tracking of weak and slow unmanned aerial vehicles (UAVs). These challenges include ISAC waveform design, clutter cancellation resilient to high clutter-to-noise ratios (CNRs), and efficient Doppler separation between UAVs and clutter. To that end, we summarize potential solutions and raise a comprehensive framework on implementing the 5Gadvanced (5G-A) GBS. Outfield experiments demonstrate that the developed 5G-A GBS can effectively track weak and slow targets at distances exceeding 1 kilometer, while incurring only a 1.2% downlink rate loss relative to commercial 5G-A GBS.