Whether networked vehicles that warn of traffic jams in real time, household appliances that can be operated remotely, wearables that monitor physical activity or industrial plants that detect any production errors in good time and notify technical support: The number of smart products that communicate wirelessly with other devices in the age of the Internet of Things has increased rapidly in recent years. However, not all of these devices are compatible with each other, as they use different wireless technologies such as Wi-Fi, Bluetooth or ZigBee, depending on the requirements and application. What's more, many devices often have the same radio frequencies and interfere with each other. This delays data transmission, data can be lost, energy consumption increases and battery life decreases.

New building block for direct communication

Researchers at the Institute of Computer Engineering at Graz University of Technology have now developed a system that enables the direct exchange of information between commercially available devices that use different radio technologies but the same radio frequencies. This is a generic framework called X-Burst, which companies will be able to integrate into the operating systems of their IoT products in the future. The researchers make use of time-controlled energy pulses - energy bursts - in the radio channel, which are generated by every smart device and can be detected by most of them: "We send standard-compliant data packets of different lengths. These packets are encoded in their length, which means that the information is stored in the duration of the packets. The receiving devices monitor the energy level in the radio channel and can therefore detect the packets, determine their duration and ultimately extract the information they contain," explain Rainer Hofmann and Hannah Brunner, who were in charge of the project together with their colleague Carlo Alberto Boano.

System supports common technologies

In their work, the researchers focused primarily on data exchange in the license-free 2.4 GHz band. This frequency range is used by many radio standards - including the most common technologies Wi-Fi, Bluetooth (Low Energy) and ZigBee - which were the focus of the investigations. Using a prototype, the team was able to demonstrate that X-Burst enables successful communication between different wireless technologies without the need for expensive and inflexible gateways, as is currently necessary for devices with different wireless technologies.

Promising benefits

The invention also makes it possible to synchronize the system clocks of the various devices, allowing them to perform certain actions at the same time, for example. X-Burst also lays the foundation for the intelligent use of radio frequencies by allowing all devices to communicate with each other and adjust their frequencies accordingly. This minimizes cross-technology interference and improves the reliability and energy consumption of the devices. The group is currently working on a new prototype that will demonstrate and illustrate the advantages of X-Burst in an actual smart home scenario.