Researchers at Aalto University in Finland have developed affordable 3D-printed devices that passively guide radio waves around physical barriers.
Higher-frequency channels of 6G communications aim to provide vastly more data bandwidth than the current 5G, but those channels are more easily blocked by walls, people and other obstacles.
This breakthough involves metacrystals, which are passive, 3D-printed smart panels that can shape wireless signals without electronics, a power supply or active tuning.
"When a room is too dark, you can bring in more lamps—or use simple mirrors to guide the already available light. This is what these metacrystals do, but with radio waves," said Mahdi Asgari, doctoral researcher. "Unlike previously proposed single-layer intelligent surfaces, these volumetric metacrystals can be designed to control multiple incoming signals or frequency bands independently, a key requirement for realistic wireless communication."
The panels could be installed on walls, ceilings, furniture, or other surfaces to redirect signals around corners, into shadowed areas or toward specific users or devices. Unlike many existing intelligent surfaces, which often perform only one task for one signal direction, the panels can handle several incoming waves at the same time, operate over different frequency bands simultaneously, work in reflection or transmission mode, and even fully absorb unwanted signals.
‘For industry, the most attractive use cases are static or slowly changing environments like factories, indoor 5G/6G networks, warehouses, and long corridors,’ says Asgari. ‘In such places, a passive panel designed for a known layout could be much cheaper and simpler than an actively controlled surface that requires continuous maintenance.’
The paper, 'Metacrystals: Inversely-designed 3D-printed intelligent panels for 6G communications' was published in Nature Communications on June 8.
IMAGE CREDIT: Aalto University / Mahdi Asgari