This article explains the requirements for an 802.11n connection to operate at maximum speed.
How to install an 802.11n wifi receiver
An 802.11n Wi-Fi network connection supports up to 300 Mbps of theoretical bandwidth under best conditions. However, an 802.11n connection sometimes operates at lower speeds, such as 150 Mbps and below.
For an 802.11n connection to work at maximum speed, Wireless-N broadband routers and network adapters must be connected to each other and operate in what is called channel bonding mode.
In 802.11n, bonding uses two adjacent Wi-Fi channels simultaneously to double the wireless link bandwidth compared to 802.11b/g. The 802.11n standard specifies that there is 300 Mbps of theoretical bandwidth available when using channel bonding.
