Transparent antenna seeks to solve 5G mmWave FWA challenges

German smart antenna startup Alcan Systems has invented a transparent antenna that you stick on a window to allow high frequency spectrum to get through.

The embrace of millimetre wave by the 5G era was celebrated as opening up vast new swathes of spectrum real estate that would enable hitherto unimaginable wireless data rates. There was just one problem, however – the propagation characteristics. While traditional low-frequency radio waves penetrate walls and windows as if they weren’t there, the higher you go, the less effective spectrum is at this.

That’s one of the reasons the main use-case for mmWave so far has been fixed wireless access, because you can just create a point to point, line of sight, fixed setup, much like the microwave communications between cellular base stations. But in this scenario the customer premises equipment (CPE) still needs to be on the outside of the building, for the aforementioned propagation reasons.

Glass, as you would expect, is easier for electromagnetic radiation to penetrate than brick, but how much easier depends on the glass, it seems. In these eco-conscious times the trend is towards low-emissivity (low-E) glass, which has superior insulating properties. The problem is that works both ways and double-glazing unit with low-E coating only allows 0.1% of the signal to get through, which is obviously not ideal.

Enter German startup Alcan Systems, which has developed a cunning piece of CPE that you stick to a window in order to make it much more welcoming to mmWave transmissions. Furthermore it uses liquid crystal technology, which makes it transparent and thus less intrusive. The complete solution combines with a glass treatment called Wavethru, developed by Japanese company AGC, to solve all your low-E glass mmWave penetration problems.

“We are very excited about the partnership with AGC and seeing the unique benefits of using liquid crystal technology, in this case, its transparent nature, allow a form factor that solves a real problem when it comes to mmWave 5G,” said Alcan Systems CEO Onur Hamza Karabey.

“The low-E glass is essential from an energy efficiency perspective and the collaboration with ALCAN ensures we can add value for our customers by meeting the requirements for high throughput anywhere in the building without affecting its appearance,” said ACG GM of biz dev Satoshi Takada.

This technology is still at an early stage and it remains to be seen whether people are willing to glue a piece of kit such as this, however transparent, to their windows. But for mmWave FWA to really take off it needs to be as cheap and effective as possible, and maybe this will be considered preferable to drilling holes in walls. You can find out a bit more about it in the vid below.