When we think of antennas, it may sound like something from the past, but we have yet to surpass them. Modern devices contain built-in antennas that are crucial for functions like cellular data, GPS, and Bluetooth, and each is adjusted to separate frequencies. Recently, researchers at Queen Mary University of London have made a breakthrough with their new method that allows antenna tuning where it was impractical before, potentially changing connectivity as we know it.
Current innovation
Researchers at Queen Mary University of London have recently demonstrated that replacing a small number of atoms with calcium in a ceramic material reproduced electrical activity in the otherwise electrically inactive area. Professor Yang Hao, lead author, compared this change to a shift from an on/off switch into a dimmer switch with more settings. This method is seemingly surpassing the performance/tunability tradeoff without any downside. Plus, it is lead-free, making it potentially environmentally friendly.
Prototype antennas and microwave devices built using the method demonstrated this capability by reproducing voltage- and temperature-driven shifts without performance drops. This also solves an engineering difficulty wherein easy-to-tune materials are simply insufficient, especially at high frequencies. By making this atomically small adjustment, the improvement in the response to electrical signals was significant.
History
To understand the importance of the finding, we have to understand that in the 80s, brick-shaped telephones had long external antennas for connectivity. Customer demand for pocket-sized phones led these antennas to first become smaller, and then completely hidden. However, antennas were not designed to be shrunk; they are made to radiate into open space, not from within a shell, surrounded by other radiating components and even our hands. On top of this, we started implementing dozens of connections into every phone with their own frequencies and tunings, driving traditional antennas to their limit.
Work towards this has been extensive, and to keep performance stable as technology changes, we’ve seen various adaptations to this principle, such as moving antennas to the outer shell of the phone. This initially caused increased connectivity issues due to phone cases or people gripping their phones, as per Steve Jobs in 2010. Though significant improvements were made, connectivity as we know it today still has problems in frequency tuning. Ferroelectric materials, which allow for tuning, have the drawback of decreasing performance, and this bottleneck has become more relevant as we broaden connectivity.
Conclusion
If antennas made in this new way take hold, they could change far more than just mobile phones or classical antenna devices. Antennas are present in nearly all devices nowadays through the Internet of Things. And, in turn, their usefulness doesn’t stop at just performance and coverage. If used commercially, this could decrease the number of antennas being used to catch the same frequencies, decrease costs, and save battery life.
Photo credit: The feature image is symbolic and has been taken by Nastya Dulhiier.
Source: Queen Mary University of London / MG Siegler (TechCrunch)
