[Updated: 10/18/2005 1:00 AM] While the struggle for the 802.11n standard continues, the fight for market dominance rages on. Currently, the three big chipset players in the pre-N high-speed wireless LAN market are Atheros, Airgo, and Ruckus (recently changed name from Video54). For a quick technical overview of the competing pre-N technologies, PCWorld did this wonderful illustration on the various MIMO technologies.
Atheros was the early leader in the dual-band 802.11a and 802.11 b/g market, but their efforts in pre-N have been lackluster compared to their competition. The only products that use the Atheros MIMO chipset are from D-Link. D-Link refused to be benchmarked at Tomsnetworking and they haven't benchmarked well anywhere else. The good news for Atheros is that I still recommend their standard 802.11a and 802.11b/g dual-band based products because they offer a lot of bang for the buck and it's like having two access points in one. This means you can put your wireless multimedia extenders on the low 2.4 GHz channel and your laptop on the 5 GHz channel where neither interferes with or degrades the other. All of the high-speed MIMO products so far in the consumer space only operate with one data stream in the crowded 2.4 GHz space which offer high performance for a single data stream, but not higher in independent data streams. While increased speed is nice, what seems to really sell the pre-N products is improved range because people want a single device that can comfortably cover the entire house no matter where the Access Point is placed.
Airgo is leading the charge in the pre-N wars in speed, range, and pre-N market share. They have companies like Belkin, Linksys, and Netgear producing Airgo's "True MIMO" and "True G" products and even have an embedded miniPCI solution for Toshiba notebooks. Airgo's solution requires the most number of radios on both the Access Point and Client side, but they've managed to simplify their chipset and keep the price increase to a minimum. One thing that I really like about the Airgo solution is that it only uses a single 20 MHz wide radio channel to transmit data whereas all the other pre-N solutions use channel binding and eat up two radio channels. When there are only 3 channels available in the 2.4 GHz band, I always prefer the single channel solution. Even though Airgo already leads the speed race, Airgo has widened the lead even further by producing a quad radio solution that uses channel binding to produce sustained data rates of over 100 mbps which is four times faster than standard 802.11g and 802.11a.
Ruckus offers a simple solution where they don't increase the number of radios in either the Access Point or Client, but uses smart-antenna technology and channel binding to achieve their enhanced range and speed. So far, only Netgear sells Ruckus' smart-antenna "BeamFlex" technology. In most benchmark tests, they're a very close second to Airgo's True MIMO technology, but Ruckus argues that their solution is a better value and cheaper because it only uses a single radio while Airgo's True MIMO technology uses two radios on the transmit side and three radios on the receive side. While it's true that there is a price difference, it works out to be about a $30 price difference in the Access Point and almost no difference in the client adapter. This might be caused by higher margins for the Ruckus BeamFlex products so the prices could theoretically come down since there are fewer radios. Since the cost of the chip-integrated radios don't make that much of a difference, most consumers probably don't care too much although all the smart-antenna manufacturers keep telling me this makes a huge difference in their chipset business. Although Ruckus BeamFlex technology uses two radio channels to transmit data, they argue that their channel binding products pollute the airwaves less because they focus the signal in a narrow beam at the client (so long as you're not in the path of someone else's beam). Ruckus also argues that their beam-forming technology is less susceptible to RF (radio frequency) interference from things like microwave ovens and other Access Points but I have not seen any independent product reviews that confirm this. I'm still waiting to get my hands on a sample so that I can verify these claims for myself. [Update: Ruckus not only sells intellectual property to companies like Netgear, but they market their own Wi-Fi gear which they offer on their website]
So far, most of the pre-N products makers are going for the bigger performance numbers and are sticking with Airgo's single radio channel multi-radio solution while Ruckus argues that they have a simpler and cheaper single-radio solution. If we consider a dual-band 2.4/5 GHz pre-N solution that doesn't exist for consumers yet, an Airgo based solution would have to have at least 4 radios on the Access Point and 2 radios on the client side. Airgo's True AG technology does exactly this, but no True AG products exist yet. A similar product that uses Ruckus BeamFlex technology could be built using only two radios on the Access Point and one radio on the client side. As for the spectrum efficiency debate, Airgo will argue that they only use a single channel while Ruckus argues they don't blast their radio signal in all directions. This same debate rages on in the 802.11n standards body.
Ultimately, it may even be possible to have coexistence since it would be possible to incorporate both Ruckus smart-antenna technology and Airgo's MIMO technology in to a single product. If I could have it all, it would be great to see a quad radio dual-band smart-antenna solution that can operate as two access points in the 2.4 GHz and 5 GHz band but also be able to operate in quad-speed mode with all 4 radios working on a single data stream.