More than 148,000 kilometers traveled in one month: that is the result of the study conducted by researchers at Fraunhofer IML and their partners. They investigated the network coverage of various technologies along the routes traveled. Comprehensive availability is important for IoT devices (IoT: Internet of Things), for example, which communicate regularly updated sensor data. In the study, the participants each attached five trackers with five different communication technologies to a total of 50 EPAL Euro pallets. They then shipped these to 24 EU countries via the Dachser logistics center in Dortmund.

The trackers each use different communication networks. These include radio technologies such as LPWAN (Low Power Wide Area Network), of which the technologies NB-IoT, LTE-M and Sigfox were considered. NB-IoT and LTE-M transmit on a 5G-compatible, licensed mobile radio frequency, while Sigfox transmits in the license-free frequency spectrum. The researchers also examined the classic second and third generation mobile networks (2G/3G). The individual technologies differ in terms of data rate, frequency range, energy consumption and range, among other things.

After a month, the pallets returned to the Fraunhofer IML and the researchers were able to evaluate the technologies used on the basis of over two million data transmissions. "The study shows that the classic 2G and 3G mobile networks still have the highest availability across Europe. However, the disadvantages of these networks are that they are sometimes switched off, allow fewer accesses per radio cell and have a higher energy consumption, which means that the trackers last less time," says Patrick Becker, research associate at Fraunhofer IML. LPWAN networks are therefore more suitable for modern logistics applications with lots of sensor data in small transmission packets. These are still constantly being expanded, but already offer nationwide network availability in some cases.

For logistical IoT applications that require continuous reception throughout Europe, the researchers at Fraunhofer IML therefore recommend a combination of LPWAN technologies (NB-IoT, LTE-M, Sigfox) and traditional mobile communications (2G-4G). This is the only way to guarantee Europe-wide data transmission at the present time. Nevertheless, the future of connectivity for IoT devices clearly lies with LPWAN technologies.