The MIMO war rages on!
When I posted the last blog on the fight for the MIMO 802.11n standard, I didn't realize that I was walking in to the middle of a raging war. An anonymous reader going by the name "Basketball Jones" using a hotmail account sent an enraged email blasting me for "buying the Airgo FUD". Among many other nasty things, Basketball Jones (if that is his name) tells me that I am obviously a fool for buying in to the whole spectrum efficiency myth and that it was all Airgo's fault for slowing the 802.11n standard. As strange as the letter was, I must admit that I got a pretty good laugh out of the whole thing. As it turns out, the arguments go right to the heart of the fight for the 802.11n standard.
I asked Basketball Jones to identify himself and so that I can give him proper attribution and let him have a chance to rebut my blog on MIMO, but he has declined to reply to my message. From what I can gather, Jones sounds like he is firmly in the TGn Sync camp and had it out for the WWiSE camp. Airgo belongs to the WWiSE alliance who's philosophy is to increase throughput and range without using more radio spectrum. The TGn Sync favors doubling the amount of radio spectrum used to increase throughput. Airgo (the company that Basketball Jones slams) currently dominates the market place against two other smaller MIMO players Video54 and Atheros.
According to Jones, I am a fool because I didn't realize that "spectrum is free". While it's obvious that radio spectrum in the narrow 2.4 GHz band really is "free", Jones fails to mention that spectrum is also very finite since the FCC has only given us three 20 MHz wide channels in the 2.4 GHz band to work with. The fact that it is free and extremely scarce means that everything must be done by the standards bodies to ensure efficient use of it. Anyone who doubts how bad the spectrum crowding situation is should read this article.
The Airgo based products have been on the shelf the longest, and continue to have the best throughput and range against its newer competition. Even more surprisingly, Airgo's True MIMO product beats the competition while using only 20 MHz of spectrum compared to a wasteful 40 MHz for the other two products. At 40 MHz, you're essentially hogging 2/3 of the usable spectrum. While some people may not care about invading their neighbor's radio air space, those same people would be the first to scream when their neighbors invade them. Basketball Jones argued that the Video54 product uses only one radio along with 7 antennas which makes it a cheaper design compared with Airgo True MIMO's triple radio design. Despite the fact that the Video54 product wastes twice the radio spectrum and still can't beat Airgo's performance numbers, I decided to see if there was any merit to the cost argument. It turns out that we're essentially talking about saving $20 off a $120 wireless router which hardly sounds like a compelling argument to hog twice as much radio frequency and still have a little less range and throughput. Then with the recent news that Airgo has released a second generation of products with tighter integration and reduced prices at a time when most other MIMO players are just starting to come to the market, we're likely to see most of that $20 gap disappear within the next month.
The 802.11n standards will most likely be forced in to a compromise to permit 40 MHz operation but mandate 20 MHz operation the minute any other access point comes within range. For most city and urban deployments of Wi-Fi, this will almost guarantee that MIMO will never operate beyond 20 MHz which means that all of the spectrum hogging gear will see no performance boost over conventional 802.11g. Airgo's technology will be the only one to achieve nearly double the speed in 20 MHz operation.