Symbol-Synchronous Communication for Ultra-Low-Power Multi-Hop Ambient IoT Networks

2026-03-24

AI Summary

This work addresses the challenge of supporting traditional multi-hop protocols in batteryless ambient Internet of Things (A-IoT) networks, where energy scarcity and dynamics hinder synchronization, channel access, and routing coordination. The authors propose a novel coordination-free networking protocol based on symbol-synchronous transmission, enabling batteryless relay nodes to asynchronously and adaptively participate in data forwarding for the first time in multi-hop A-IoT settings. By integrating symbol-level synchronization, energy-adaptive duty cycling, and a coordination-free relaying strategy, the protocol substantially reduces synchronization and signaling overhead. Experimental results demonstrate that in a 625 m² deployment with 400 nodes, the system achieves an average wake-up duty cycle of only 6%, a packet error rate below 1%, and 88% energy savings compared to baseline approaches, significantly enhancing both energy efficiency and deployment flexibility.

Technology Category

• Application Domains: Internet of Things, Sensor Networks & Smart Cities
• Multiagent Systems: Coordination and Collaboration
• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Energy management for devices in mobile Web and WoT environments
• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs
• Economics, Online Markets and Human Computation: Incentives in network design for Web infrastructures and ecosystems

Abstract

Ambient Internet of Things (A-IoT) devices, as a critical enabler of future green IoT networks, have attracted broad interest from both industry and academia due to their ability to operate without batteries and with low maintenance costs. To accommodate their dynamic and constrained energy budget, an ultra-low-power connectivity protocol is required. Due to the severely limited transmit power of A-IoT devices, multi-hop connectivity is an interesting paradigm to extend their range. However, commonly used protocols for multi-hop communication may not be suitable for A-IoT due to excessive overhead related to channel access procedures, coordinated routing, and tight time synchronization requirements. This paper presents a novel network connectivity protocol based on symbol-synchronous transmissions, which allows battery-less relay nodes to participate in the forwarding process in an ad-hoc manner, without the need for synchronization or coordination. This allows them to adapt their duty cycle to the available harvested energy. Simulation results show that the proposed protocol can ensure high reliability in data packet delivery while significantly reducing the energy consumption of each relay node. We also investigate the relationship between wake-up probability and network density. For example, a 400-node network in a 625 m2 area can achieve a packet error rate below 1 % with an average awake time of 6 % per node, achieving an energy consumption reduction of 88 % compared to the baseline approach.

Problem

• Ambient IoT
• multi-hop communication
• ultra-low-power
• energy-constrained networks
• symbol-synchronous

Innovation

• symbol-synchronous communication
• ambient IoT
• ultra-low-power networking
• battery-less relay
• multi-hop communication