Forum

Greetings all!

Quick question regarding 802.11a upgrades. A healthcare customer has 5 hospitals, all sites use Cisco's 1231 AP with 2.2dBi ceiling omni antennas - 2 are at 30mW b/g, 3 are at 50mW b/g. They want to add 802.11a modules to the APs. I have surveyed some smaller pilot areas that have the b/g radios set to 30mW and the "a" radio set to 12mW (1231 max) using Cisco's 3.5dBi dipoles. For these areas, it appears the "a" coverage is a seamless overlay.

My question is how well will "a" overlap the b/g coverage in the other hospitals where the b/g was surveyed at 50mW if I use Cisco's 4.5dBi ceiling antenna for the "a" radio? Has anyone had experience such as this?

Thanks,
- Paul

802.11a should work with no problem for you. However, to get the same coverage that the b/g radios are giving you may need to increase the power on the a radios, use higher gain antenna or co-locate more 802.11a radio AP's, due to the smaller wave and higher frequency used. A seperate survey of a coverage and throughput is also desired. There are too many variables to give a yes or no answer here.

PS Welcome to the Forums!!!!

Hi paulzinda,

Your question is really a complex design issue.

In order to get a good perspective on where to take this scenario, I highly suggest you visit http://www.arubanetworks.com/technology/whitepapers/
and then read the whitepapers from The Farpoint Group called:

1) Rethinking the Access Point: Dense Deployments for Wireless LANs

and

2) Beyond the Site Survey

thanks,

Devinator