Autonomous Agricultural Monitoring with Aerial Drones and RF Energy-Harvesting Sensor Tags

TL;DR

This paper investigates battery-free wireless tags powered by energy harvested from an aerial drone to enable low-cost, maintenance-light environmental sensing in precision agriculture. It implements a UAV-mounted payload with a BLE-transmitting, AES-encrypted tag system and a cloud-based decryption/gateway pipeline, using the AERPAW platform for experimentation. The results show feasibility in ground tests but airborne trials are hindered by drone-induced electromagnetic interference, highlighting EMI as a key challenge and suggesting design refinements such as hardware unification and EMI mitigation. The work advances the concept of drone-powered, battery-less sensing for scalable agricultural monitoring, and outlines concrete steps toward more robust, autonomous UAV-based data collection.

Abstract

In precision agriculture and plant science, there is an increasing demand for wireless sensors that are easy to deploy, maintain, and monitor. This paper investigates a novel approach that leverages recent advances in extremely low-power wireless communication and sensing, as well as the rapidly increasing availability of unmanned aerial vehicle (UAV) platforms. By mounting a specialized wireless payload on a UAV, battery-less sensor tags can harvest wireless beacon signals emitted from the drone, dramatically reducing the cost per sensor. These tags can measure environmental information such as temperature and humidity, then encrypt and transmit the data in the range of several meters. An experimental implementation was constructed at AERPAW, an NSF-funded wireless aerial drone research platform. While ground-based tests confirmed reliable sensor operation and data collection, airborne trials encountered wireless interference that impeded successfully detecting tag data. Despite these challenges, our results suggest further refinements could improve reliability and advance precision agriculture and agrarian research.

Figures (6)

• Figure 1: A manual drone flight hovering above the target box with tags attached. On the left, a laptop was used to monitor data collection.
• Figure 2: Gives a lab setup demonstrating how the tags (left) are energized and transmit data to the bridge (right top). The bridge then relays the data to a gateway (cellphone, bottom right) with internet connectivity to decrypt the data via an online service.
• Figure 3: Shows the state machine flight diagram for the programmed autonomous data collection.
• Figure 4: Shows the block diagram of the small drone. Platform 1 is provided by AERPAW. Platform 2 is the custom payload node. The custom node allows the drone to energize and collect encrypted data packets from the tags, and relay them in real-time to a decryption service. The decrypted data is then stored within a remote database.
• Figure 5: Shows the experimental wireless platform assembly. The white circular object to the left is the tag bridge with an attached mounting plate and buck converter for power. To the right is the cell phone that slides between the bridge and mounting plate and is held in place with a retaining clip.