Wireless 802.11n Standard: 150Mb/s

[Roadrunner]

Visitied a friend last night who was busy installing this wireless adapter into his machine:

http://www.intellinet-network.com/en-US/products/9024-wireless-150n-usb-mini-adapter

I was curious to see that it was specified as maxing out at 150Mb/s, but also has the 8021.11n wireless networking specification printed on the box.

Doesn't the 802.11n standard define a maximum speed of 300Mb/s?

My guess is this model only use one antenna and not the MIMO setup,so only attains half of the speed? If so, then why is it also included in this specification?

 

[Rudimental]

802.11n is 600Mb/s max, in the form of 150Mb/s x 4 (MIMO), one for each aerial/stream, iirc. It's a quarter of the maximum speed, but still amost 3 times faster than 802.11g. I have heard of some rumblings about poor performance on draft n networks running with compatibility for b/g devices. So maybe that is another reason.