Wireless N Adapters:
One of the most overlooked parts of your wireless network is what type of wireless adapter you have in your desktop or laptop computer. Most people focus on what type of wireless router or wireless access point they will install as there gateway. The problem with this is that your Wireless N router is only the road and the wireless adapter is the car that drives on the road. If your adapter is slow than your network will be slow.
First you will not want to allow 802.11b wireless adapters on your network. If you allow a wireless 802.11b client on your net work your network must adjust for the slower speed by allowing extra management frames to allow the 802.11b to keep up with the Wireless G ad Wireless N clients.
Second If you just purchased a wireless N router and bring it home and have the same speeds as before more that likely you have a wireless g network adapter installed in your laptop. You will never get the advertised 300 mbps throughput that is advertised but you do need a wireless N adapter on your laptop to have a benefit. Even better would be to have a adapter that is made by the manufacture as your wireless router or gateway. Wireless vendors have interpreted the draft wireless n in many ways and often have their own engineering twist with their drivers to achieve faster speeds.
Sensitivity of the wireless adapter means how good your wireless n adapters “hearing” are. The farther you move from your wireless router the slower you speeds will be. If you have a wireless adapter with a poor sensitivity rating your speeds will drop off very quickly.
Finally you need to make sure that your wireless adapters driver is the most up to date driver available from the vendor. These updates are very important and may fix any connectivity problems you have experienced.
Wireless N adapters are the best adapters to buy at this point even if you have a wireless G network. They are newer and have the best sensitivity ratings.