Misusing MIMO

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Tim Higgins

Ralink this week announced a new 802.11n chipset with a carefully-crafted pitch. 802.11n tends to be thought of as using MIMO technology to achieve its 100Mbps+ speeds. But the chipset doesn’t use MIMO and Ralink doesn’t use the term in its announcement.

Instead, the RT2700 chipset is described as using a “1T2R” (one transmit, two receive) configuration that the company says is “capable of up to 300 Mbps downstream and 150 Mbps upstream PHY rates”. And while Ralink doesn’t say “1T2R” is MIMO, which it isn’t, the enumeration of transmit and receive channels implies MIMO technology, since this is common practice for MIMO products.

The next example pushes the envelope a bit further. Buffalo has changed the name of its WHR-HP-G54 wireless router and WLI-CB-G54HP notebook card from “Turbo G High Power” to “Wireless-G MIMO Performance”. To its credit, Buffalo appends an asterisk to each use of “MIMO Performance” that links to a clear disclaimer. The disclaimer states that the products are not designed to 802.11n, but “outperform[s] two radio/three antenna MIMO technology beyond certain distances”.

Those of us who have been around the wireless LAN block a few times understand what is being said. But do you think the typical wireless buyer trolling the aisles looking to solve his crappy wireless connection does? They are more likely to see the all-caps “MIMO” with the lower price (than other “MIMO” products) and take it home.

The last example is the worst of the three. SMC’s “g MIMO” product line might be using the Ralink chip, since it uses the specific “1T2R” terminology that Ralink uses. But SMC goes right ahead and puts MIMO right into the product name, gives the products three antennas (just like real MIMO products have) and has no disclaimers on the products’ website descriptions or downloaded datasheets.

So even as technology marches on and wireless performance is entering an era of true higher performance, consumers must continue to be on guard. Marketeers are continuing to do their jobs, which is to get you to buy their company’s products. And so you must continue to do your job, which is to arm yourself with knowledge so that you can choose products wisely.

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