On-Demand TDMA for Energy Efficient Data Collection with LoRa and Wake-up Receiver

TL;DR

This paper introduces an energy-efficient on-demand TDMA scheme combined with wake-up receivers for LoRa networks, significantly reducing latency and power consumption while maintaining high data reliability in IoT deployments.

Contribution

It proposes a novel heterogeneous network architecture and communication scheme that enhances LoRa performance with ultra-low power wake-up receivers and on-demand scheduling.

Findings

100% data reliability achieved

Milliseconds round-trip latency demonstrated

Devices last up to 3 years on a single battery

Abstract

Low-power and long-range communication tech- nologies such as LoRa are becoming popular in IoT applications due to their ability to cover kilometers range with milliwatt of power consumption. One of the major drawbacks of LoRa is the data latency and the traffic congestion when the number of devices in the network increases. Especially, the latency arises due to the extreme duty cycling of LoRa end-nodes for reducing the overall energy consumption. To overcome this drawback, we propose a heterogeneous network architecture and an energy-efficient On-demand TDMA communication scheme improving both the device lifetime and the data latency of standard LoRa networks. We combine the capabilities of micro- watt wake-up receivers to achieve ultra-low power states and pure asynchronous communication together with the long-range connectivity of LoRa. Experimental results show a data reliability of 100% and a round-trip latency on the order of milliseconds with end devices dissipating less than 46 mJ when active and 1.83 {\mu}W during periods of inactivity, lasting up to 3 years on a 1200 mAh Lithium battery.