Description of 802.11a standard that works on 5 GHz.

802.11a products work on the frequency of 5 GHz, which is an unlicensed band. Standard hit the market in late 2001. There were three main chipset vendors: Intersil, Cisco (you have guessed this one for sure) and Atheros Communications.

Higher frequencies have higher path losses. This means also that 11a Access Points have the lower range. Much greater density is needed. Higher frequency requires a greater power – more power consumption.

Good side of a standard is the bandwidth. Maximum bandwidth is 54Mbps, which is almost 5 times greater comparing to 802.11b.

11a uses OFDM – Orthogonal Frequency Division Multiplexing.

It is not so popular, because less expensive 802.11b was already widely adapted. Vendors of the equipment have improved initial product implementations by increasing the range almost to 802.11b.