"Take Me Home, Wi-Fi Drone": A Drone-based Wireless System for Wilderness Search and Rescue

2026-04-10

AI Summary

This work addresses the challenge of locating missing persons in remote, infrastructure-free environments characterized by severe occlusion and limited communication. To this end, the authors propose a drone-based active Wi-Fi probing system that emulates previously connected Wi-Fi networks to trigger automatic reconnection attempts from the victim’s device. The system integrates a fast, low-power device discovery mechanism, a long-range received signal strength (RSS)-based direction-finding algorithm enhanced by a 3D-printed Luneburg lens, and an adaptive drone navigation strategy to efficiently localize and approach the target. Extensive experiments conducted across diverse real-world outdoor scenarios demonstrate the system’s effectiveness, significantly extending detection range and enabling precise drone guidance to the victim’s location.

Technology Category

• Intelligent Robots: Localization, Mapping, and Navigation
• Search and Optimization: Local Search
• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Location- and context-aware Web and WoT applications and services
• Graph Algorithms and Modeling for the Web: Representation, reconstruction, and subgraph or motif discovery in Web-related graphs
• Responsible Web: Human-perceived consequences of algorithmic deployment on the web

Abstract

Wilderness Search and Rescue (WiSAR) represents a longstanding and critical societal challenge, demanding innovative and automatic technological solutions. In this paper, we introduce Wi2SAR, a novel autonomous drone-based wireless system for long-range, through-occlusion WiSAR operations, without relying on existing infrastructure. Our basic insight is to leverage the automatic reconnection behavior of modern Wi-Fi devices to known networks. By mimicking these networks via on-drone Wi-Fi, Wi2SAR uniquely facilitates the discovery and localization of victims through their accompanying mobile devices. Translating this simple idea into a practical system poses substantial technical challenges. Wi2SAR overcomes these challenges via three distinct innovations: (1) a rapid and energy-efficient device discovery mechanism to discover and identify the target victim, (2) a novel RSS-only, long-range direction finding approach using a 3D-printed Luneburg Lens, amplifying the directional signal strength differences and significantly extending the operational range, and (3) an adaptive drone navigation scheme that guides the drone toward the target efficiently. We implement an end-to-end prototype and evaluate Wi2SAR across various mobile devices and real-world wilderness scenarios. Experimental results demonstrate Wi2SAR's high performance, efficiency, and practicality, highlighting its potential to advance autonomous WiSAR solutions. Wi2SAR is open-sourced at https://aiot-lab.github.io/Wi2SAR to facilitate further research and real-world deployment.

Problem

• Wilderness Search and Rescue
• Wi-Fi-based localization
• Drone-based system
• Through-occlusion detection
• Autonomous search

Innovation

• Wi-Fi-based localization
• Luneburg Lens
• wilderness search and rescue
• drone navigation
• infrastructure-free sensing