Somes a bug can be a feature. Consider atmospheric attenuation of radio frequency signals at 60 GHz, At that frequency, oxygen in the atmosphere attenuates about 98 percent of the emitted energy. That limits coverage.
So it might be paradoxical that Terragraph is working to commercialize use of 60-GHz frequencies for internet access. At the same time, many internet access providers say they are going to use fixed wireless for internet access.
One advantage of 60-GHz spectrum, in the U.S. market and in most countries is that the spectrum is available for unlicensed use. That has huge business case implications for service providers compared to the alternative of building fiber-to-location networks.
In the U.S. market, where consumer internet access is dominated by cable TV companies, fixed wireless might be the main way telcos can compete with cable offers. When the cable operator has about 70 percent of the installed base, the fiber to home cost per passing or cost per customer is a tough business case.
In addition to no requirement to pay for a license to use the spectrum, the bandwidth is huge, about 14 GHz of capacity in the 57 GHz to 71 GHZ band available for U.S. unlicensed use.
Another advantage is security. Because signal attenuation is so high, stray signals are confined. In an indoor Wi-Fi deployment, the signals will not often “leak” out of the building. In an outdoor access deployment, the signals can be highly linear, reducing the chances of accidental or purposeful unauthorized signal reception.
There are interference protection advantages as well, In an indoors Wi-Fi deployment (local area network), adjacent 60-GHz transmitters are less likely to interfere with each other, which causes a reduction in experienced speeds and capacity.
The same goes for line-of-sight, or near line-of-sight 60-GHz access transmitters: signals from one radio are less likely to interfere with signals from other transmitters.
Frequency reuse opportunities also are quite high, again a function of the “bug” of extremely-high signal attenuation. In the same way that small cells boost the intensity of usage for any specific block of spectrum, so 60-GHz signal attenuation allows a high degree “cellular” frequency reuse.
Though high signal attenuation would seem to be a major bug, it might also be a key feature for 60-GHz frequency internet access.
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