No 5 GHz-Capable 802.11n USB Dongle In Sight

Although mobile WiMax is as new a technology as any other wireless standard, there are at least two different vendors that have WiMax-capable USB dongles available on the market (Wavesat being one of them). Unfortunately, that doesn't seem to be the case with 5-GHz 802.11n, even though SOHO manufacturers have been pumping out 802.11n-like product for over a year. Vendors, analysts, and trade press have all been presenting a pretty consistent message regarding the deployment of 802.11n: deploy primarily at 5 GHz, support 2.4 GHz as feasible or capable. Using 5 GHz for your 802.11n deployment avoids competing with legacy 802.11b/g clients operating at 2.4 GHz, allows for the greatest possible speeds, facilitates the channel planning process as 5 GHz has a large number of nonoverlapping channels, and it tends to be more interference free than 2.4 GHz. Even if you can't deploy 5 GHz 802.11n in Greenfield mode because you need to serve 802.11a clients, at least you're not dragging your aggregate throughput down because of slower 802.11b clients.

Although most major laptop manufacturers have been offering embedded dual-band 802.11n products for several months now, there are those who may have acquired a laptop before that time, or those who didn't take it into consideration when making their purchase and now want to have access to the faster speeds and more reliable connections provided via MIMO. The easiest solution (and most palatable for end-users) is a USB dongle. Unfortunately, a dual-radio version of such a dongle doesn't exist.

There are more than a handful of 2.4-GHz 802.11n-capable USB dongles, but to date, I'm not aware of a 5 GHz one. Morrisville State College, the earliest significantly sized (publicly announced) 802.11n deployment, has been on the search for several months, but hasn't turned one up. It's not that there's no silicon for them. Atheros has its AR9001U-2NX, but there???s no product using it, at least on the shelf. In the meantime, Morrisville will be using the 2.4 GHz range for its USB clients. This is not a significant issue because Meru's architecture supports a single-channel deployment model and Morrisville didn't have a legacy base of production 802.11b/g clients, having previously used an FHSS-based 802.11 system.

This lack of 5 GHz-capable USB dongle availability shouldn't be a show-stopper for any pilot or deployment, but another data point that 802.11n is still in its earliest stages.