Rx/Tx Setting for 350AP and 5.2dBi Omni Antenna's

[bhenning]

I'm installing 350AP's with external 5.2 dBi omni antenna's. Two questions:

1.) How far apart should I mount the right and left anntenna's on the drop ceiling crossmember? (six inches?)

2.) How should I configure the access point Rx and Tx settings? Should I use the "diversity" option? The Cisco doc's say to only use diversity with non-removable antennas, and if you have a high-gain removable antenna on the right side, then select "right" for both Rx and Tx; if the antenna is on the left side, then select "left" obviously. Since I have high-gain omni's on both sides and I want to use both, will "diversity" work okay?

Thanks a lot for any help.

[p.krane]

Our antenna’s look like their about 8-12 inches apart. I would definitely put a call into Cisco on the other question. Come back and let me know what you learn.

[bhenning]

The Cisco TAC support person I spoke with was very resourceful for this issue. Using the diversity option with removeable omnidirectional antenna's is a good design, so long as both antenna's are near each other (such as 8-12 inches) to cover the same area. Apparently many customers try to use diversity and place antenna's at opposite ends of a building or one inside and one outside of a building (for smoke breaks I guess? ) thinking they will get more coverage. Since the access point only uses one antenna for Tx/Rx at a time, only one side of the building in that situation is going to have good reception. Hope that helps.

[6tbahney]

Thanks for the information. That is exactly the answer I was looking for.

[jhelm]

Brock,

at a minimum you would want the antennas approximately 4 to 5 inches apart. These medium range Omni antennas work very well for many environments however in the healthcare environment they may have an intrusive impact to the environment depending on where you place them and for what reason. Although you will likely find very good coverage from these you should know that there are other antenna solutions that may fit well in your healthcare applications.

If you have any questions or concerns please feel free to contact me at jhelm@netcomitl.com, we have provided a great deal of wireless engineering in healthcare for many many years.