FUJITSU Laboratories has developed a thin, light-weight and flexible IoT beacon that requires no battery replacement.
The beacon weighs in at 3g, with a thickness of 2.5mm. With no maintenance required, and flexibility that allows for installation on round objects, corners and curves, the beacon will slash the time needed to install and operate the equipment.
Previously, beacons that did not require battery replacement needed power-supply components, such as power-management ICs and secondary batteries, as control circuits to ensure adequate power on activation. These components resulted in the beacons themselves becoming rigid and large, limiting their application.
The beacon has newly developed power-control technology that temporarily deactivates the power monitor, making it possible to activate the beacon with the power from a solar cell. This then eliminates the need for conventional power supply components, allowing the beacons to be made smaller and slimmer. By using thin, elastic silicone sheets as the substrate, the beacon becomes thin, flexible and conformable to objects.
There is growing interest in low-power beacons that use the Bluetooth Low Energy(2) communications standard as a technology supporting Internet-of-Things (IoT) systems, which connect a wide variety of different devices and sensors in networks.
Compact beacons, often running on coin-cell batteries, can easily communicate with smartphones so they are starting to be installed in underground areas or indoors for field trials of IoT systems.
However, battery replacement is labour-intensive, and traditionally beacons have been less compact, making them unsightly and difficult to install in some environments.
Wireless-communications modules typically consume a relatively high amount of power. When using solar cells with low power-generation capacity, the conventional approach is to store the energy, and use the power later. This means the modules required power-control systems that monitor whether enough power has been stored for activation, and, when a sufficient amount has been accumulated, and use the energy to transition to communications mode.
This required the use of a power-management IC equipped with power-monitoring circuitry, and relatively large storage elements such as a secondary battery. This meant that it would difficult to change the appearance of the beacons.
Fujitsu has developed power-control technology that handles power monitoring while using little power, obviating the need for power-management ICs, secondary batteries, and other energy-storage elements. When used for a beacon, this technology allows for power control using an assembly of compact, slim components.
When mounted on thin elastic sheets along with a solar cell, this results in beacons that do not need battery replacements, and that remain thin and flexible, allowing them to be bent during installation.
Because the Fujitsu innovation reduces the power consumed for the power-monitoring transition just before starting communications, it becomes possible to supply the power needed to activate the wireless-communications module using a small storage element connected to a solar cell. This storage element is only one-ninth the size of those used with previous technologies, and there is no need for extended storage batteries.
Reducing the power consumed just before starting communications also has the effect of reducing voltage fluctuations when power is being used, obviating the need for a power-management IC.
Fujitsu is currently conducting field testing to establish the beacon's reliability and continuous operation, and is aiming for practical implementation in fiscal 2016. The technology has the potential to expand opportunities for using the IoT to connect information about people and objects.