Given its commercial Google Fiber service, as well as Wi-Fi networks at other venues, plus Project Loon tests, and its ownership of an unmanned aerial vehicle company, all of which deal with ways of providing Internet access, it might not be totally surprising, or even unexpected, that Google wants to test millimeter wave radio access systems as well.
Google has asked the U.S. Federal Communications Commission for permission to conduct tests in California across different high-frequency spectrum bands, including millimeter-wave systems operating in the 71 GHz to 76 GHz band and the 81 GHz to 86 GHz range.
Those bands have not been used for communications purposes in the past.
Google also has asked to test systems in the 5.8 GHz band as well, at three sites in the San Francisco Bay Area, including one in San Mateo county and two locations a half-mile apart which appear to be on Google’s Mountain View, California campus, according to Reuters.
Historically, the millimeter bands have not been so useful for communications purposes because of distance limitations and the requirement for line-of-sight paths. That has meant millimeter communications have been practical for point-to-point backhaul connections.
Rain fade and other signal attenuation issues have limited theoretical reach to a kilometer or less.
In the United States, the 38.6 GHz to 40.0 GHz band is used for licensed high-speed microwave data links, and the 60 GHz band can be used for unlicensed short range (1.7 km) data links.
The 71 GHz to 76 GHz, 81 GHz to 86 GHz and 92 GHz to 95 GHz bands are also used for point-to-point communication links.
The upcoming Wi-Fi standard IEEE 802.11ad will run on the 60 GHz (V band) spectrum with data transfer rates of up to 7 Gbps, and might be properly considered a local distribution platform (as a local area network technology), rather than a local access (connection between a place and the wide area network) platform.
The issue is how much can be done, using antenna arrays and spatial division, for example, to create an Internet access capability, beyond point-to-point backhaul.
All of that exploration by Google, and growing efforts by Facebook, does raise the question of vertical integration, to some extent. Google Fiber already creates a vertically-integrated operation that combines access, managed apps and then, in a less direct way, Internet apps.
That somewhat resembles the way telcos or cable TV companies, TV broadcasters and radio broadcasters earlier integrated access and apps.
Apple is another firm with potentially similar interests, though coming at the issue as a supplier of managed apps (iTunes, App Store) and devices. Some have suggested there could come a day when Apple might want to package apps, devices and access.
All that illustrates what might be an obvious point: it arguably is easier for tier one app or device suppliers to add access, than it is for tier one access providers to add devices and apps.
Spectrum Futures 2014
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