(Originally posted at http://www.von.com/blogs/guest/2009/02/white-space-wi-fi-on-drugs.aspx )
Firstly, I’d like to say that I applaud the FCC for opening up additional unlicensed spectrum for Internet use, but “white space” has set a new record for going from zero to the Peak of Inflated Expectations!
When Larry Page speaks of Google’s vision of “Wi-Fi on steroids,” it has a nice ring to it, but where have we heard that before? Hold on. Maybe it was three years ago, when Intel touted that WiMAX “was like Wi-Fi on steroids” and demonstrated a point-to-point link streaming video over 12 miles. In the same article, Clearwire had “introduced a precursor to WiMAX in four cities in Florida, Texas, and Minnesota, and hopes to use Intel's technology to add 16 more cities by year end.” Fast-forward three years, and Clearwire WiMAX service is available in Baltimore and Portland, and promises download speeds of “up to 6mbps,” hardly steroid like performance.
What does it mean to be “on steroids” anyways? Does it mean higher data rates? Increased range? Greater capacity?
In wireless, things are seldom cut and dry.
Many have commented on the increased range of a radio operating in the 50-700MHz bands as opposed to the 2.4GHz or 5GHz unlicensed bands. Technically, this is true, and these propagation characteristics are of value if there is a wide area to cover, and a relatively few devices. To achieve this, the base stations will look more like cell towers than wireless LAN APs, due to the very long (6m at 50MHz!) wavelength at these low frequencies. However, propagation is a double-edged sword. In environments where capacity is more of a consideration, frequency re-use is an imperative, and white space propagation will work against you.
Many have commented on the ability of 50-700MHz to penetrate walls. The answer here is, “Yes, the free space loss in these bands will be anything from 11 to 32dB better than Wi-Fi, so outdoor range in open areas will be much improved. And yes, the attenuation through materials such as concrete will be improved (maybe up to 10dB) but the long wavelength will make aperture effects -- like going through windows -- worse than at 2.4GHz.” Bottom line -- the jury is still out!
With respect to data rates, it is important to appreciate that the channel widths in white space are 6MHz as opposed to the 20MHz channels found with Wi-Fi in the unlicensed bands today. For this reason alone, it will be impossible for user performance to approach that which is currently available today. Then when macro-cell architectures are factored in, it won’t even be close. So much for Wi-Fi on amphetamines, Mr. Commissioner!
Stephen Rayment, BelAir’s CTO, recently drilled down into many of the specifics around white space in an online webinar. Sitting on IEEE committees, Stephen has first-hand visibility into many of the issues related to standards adoption, chipset availability and so on. It’s definitely worth a listen.
The industry does itself a disservice when it uses sound bites to articulate a position. Had Larry Page or Kevin Martin said, “Television white space will allow the Open Internet to bridge the Digital Divide, by bringing the web to rural areas across America,” it would have been equally compelling and more accurate.
As it stands, the Gartner Hype Cycle lives on with “white space,” but we’d all be better off if more of an effort was made to temper expectations with realistic dialogue. The eventual disillusionment would be less acute.
Drugs make for bad similes. We tell our kids that steroids are bad. They’re bad for athletes and they’re equally bad for technology.
That’s my .02!
Martin Suter
Martin Suter is vice president of business development at BelAir Networks, a provider of broadband mesh solutions for Wi-Fi, WiMAX, 4.9 GHz Public Safety and 5.9 GHz ITS networks. Previously, Martin was the CEO at Cohda Wireless, where he raised the company’s profile and negotiated a licensing deal with a Fortune 100 vendor in its core franchise. Prior to Cohda, he was vice president of business development at MeshNetworks Inc., a classic tech transfer/disruptive technology success story that achieved a major liquidity event for its investors in Q4/2004 with its acquisition by Motorola. Martin also was responsible for building several high profile alliances with and for leading technology companies, including Fujitsu, Microsoft, Netscape, Sun Microsystems, and Teradata. Additionally, Martin has successfully negotiated technology transfer, distribution and/or licensing deals with companies like 3Com, BioChem Pharma, Dow Chemical, Exodus, Fujitsu, IBM, Microsoft, Motorola, Netscape and Sun.
