Emil Björnson

Title of the project
Recycling Wireless Signal Energy in the Digitalized Society

Background and summary of fellowship:
Wireless connectivity is a key enabler for the digital transformation of society, and we start to take its availability for granted. Although the wireless data speeds have grown tremendously, we still experience unreliable wireless coverage; for example, video streaming might work flawlessly until it suddenly stalls when you walk around a corner. The Digital Futures fellowship will enable my research group at KTH to tackle this challenge. We need to explore new ways of building wireless network infrastructure to make coverage holes an issue of the past. 

Two particular solutions will be explored. The first is to spread out base stations over the city, instead of collecting them in towers, to increase the chance that every location is covered by some of them. The second solution is to make use of reconfigurable “mirrors”, which are thin plates that can be placed on buildings to reflect signals in controllable ways to remove coverage holes. These mirrors are not moved mechanically but change their electrical properties to achieve the same effect. The project will also explore how the “spill energy” from wireless signals can be utilized to power the batteries of devices, particularly internet-of-things equipment that is not operated by humans.