Did MIMO run over Eileen McCluskey's bike as a kid? I'm slightly baffled by the treatment of MIMO technology in this otherwise reasonable set of consumer advice about Wi-Fi in the Boston Globe yesterday. It's possible the single source cited in the article poisoned her information well.
"These Multi Input, Multi Output gadgets achieve excellent signal quality and range by hogging the wireless spectrum up to 219 yards away. If you live in the city or suburbs, your MIMO router will knock out your wireless-enabled neighbors' connections." Huh?
Here's my letter to the editor just sent off to the Globe:
"Less Is More" (Apr. 9, 2005) contains a glaring error regarding multiple antenna wireless networking. The reporter says that MIMO (multiple not "multi" input/output) gateways hog spectrum and knock out neighbors' reception. This is entirely untrue. MIMO gateways for Wi-Fi, unlike previous range-extending Wi-Fi, are more sensitive receivers not more powerful transmitters.
It used to be that to extend range, you pumped up the volume (increased signal power output), which could interfere with neighboring networks. MIMO uses several antennas to better reconcile radio signals as they reflect off walls and metal objects. This allows the technology to more discretely receive fainter or less clear signals from further away.
There is the danger that a newer form of Wi-Fi, called 802.11n, that will be on the market soon may interfere with older networks in some cases, but Wi-Fi product makers haven't finalized the standard, and it's one of their key concerns.
The other also states that MIMO won't work with free Wi-Fi hotspots. This is entirely untrue. Current MIMO gateways and future gatweays that use MIMO as one piece in a faster Wi-Fi standard are entirely compatible with Wi-Fi equipment sold as long as ago as the first devices in 1999. MIMO devices won't communicate at their highest possible speeds except with compatible devices from the same maker (today) or with the newer standard with any maker (in about 3 to 6 months).