That is the port/connecter type, not your DATA rate.

Router and wireless network adapters are all 802.11 protocal.
But there are different levels or variations of the protocol
802.11 a
802.11 b
802.11 c
802.11 g
802.11 n
802.11 n+
The oldest and slowest is a, the newest and fastest is n+.
You have a fast router.  If you match it to a fast wireless adapter, you can get it's full wireless data rate. 
But a router with 802.11 a is just as fast as a router with 802.11 n when you are connecting your computer to it with a network cable.