Wake-up radios: circuits, systems, and applications
Abstract
In most of deployed IoT networks, radio communications are one of the most, if not the most, energy consuming tasks of a wireless sensor node. Besides research works on medium access to reduce radio activity, designing Ultra Low Power (ULP) radio technologies represents an efficient mean to reduce this energy expenditure. Among ULP radios, Wake-up Receivers (WuRx) form an emerging mixed (analog/digital) technology which allows continuous channel monitoring while consuming orders of magnitude less power than traditional transceivers. These devices wake up the node microcontroller or other sleeping subsystems using interrupts only when a specific signal, called Wake-up Beacon is detected. Recent ULP WuRx provide computational capabilities that make it possible to perform address matching directly on the ULP WuRx, but also to activate a node sub-system or to change the sensor sampling rate, with a significant amount of energy saved and a reduced latency.
However, many technical barriers are still to be lifted as the robustness of wake-up radios, which are by nature very sensitive and therefore subject to noise perturbations. Energy is also a crucial point since the more nodes will be deployed the less batteries should be. This means efficient power management policies have to be designed at both node and network levels to ensure the longest possible lifetime for the nodes. New mechanisms have to be proposed to ensure the traffic fluidity and multi-homing management.
This special session is intended to give a good overview of current works in the area of ULP radio and wake-up receivers. Problems and solutions in specific industry use cases are welcome.
In most of deployed IoT networks, radio communications are one of the most, if not the most, energy consuming tasks of a wireless sensor node. Besides research works on medium access to reduce radio activity, designing Ultra Low Power (ULP) radio technologies represents an efficient mean to reduce this energy expenditure. Among ULP radios, Wake-up Receivers (WuRx) form an emerging mixed (analog/digital) technology which allows continuous channel monitoring while consuming orders of magnitude less power than traditional transceivers. These devices wake up the node microcontroller or other sleeping subsystems using interrupts only when a specific signal, called Wake-up Beacon is detected. Recent ULP WuRx provide computational capabilities that make it possible to perform address matching directly on the ULP WuRx, but also to activate a node sub-system or to change the sensor sampling rate, with a significant amount of energy saved and a reduced latency.
However, many technical barriers are still to be lifted as the robustness of wake-up radios, which are by nature very sensitive and therefore subject to noise perturbations. Energy is also a crucial point since the more nodes will be deployed the less batteries should be. This means efficient power management policies have to be designed at both node and network levels to ensure the longest possible lifetime for the nodes. New mechanisms have to be proposed to ensure the traffic fluidity and multi-homing management.
This special session is intended to give a good overview of current works in the area of ULP radio and wake-up receivers. Problems and solutions in specific industry use cases are welcome.