Yagi antenna questions.

joeldc · ‎01-10-2008

Hi all,

We are deploying Cisco 1242 wireless in our campus. In a couple of our buildings we have long hallways (>200ft) with glass exterior walls. We are thinking of using Yagi AIR-ANT2410Y-R antennas to cover the long hallways.

Questions:

1. Is there a way to ceiling-mount the yagi? Can I use the AIR-ACC2662 mount to hang from the ceiling so the yagi is oriented horizontally?

2. If the yagi is mounted about 12 foot above the floor, about how much area in front of the yagi won't be covered due to the angle of the signal.

3. Would there be a problem if 2 yagis are facing each other? We have a very long hallway that we're thinking of covering using yagis in the middle. If we put the yagis back to back (about 15 ft from each other) then we won't cover the middle area. So we're thinking of having them oriented facing each other to provide some coverage in the middle. (hope this makes sense).

Appreciate any information as we've never used Yagis before.

scottmac · ‎01-11-2008

Two hundred feet is not really that far; you could easily cover that well with some patch or sector antennas.

Are you looking for mobile / roam coverage (moving devices) or just trying to get signal from one end of the hall to the other end (area-to-area bridging)?

The beamwidth of a yagi at two hundred (or less) is not really practical for mobile / roam.

Depending on where you are located, you may find that the EIRP (radiated power level) off the front of the yagi is above recommended / desired human exposure levels for anyone within the middle half of the hallway.

IMO, you'd do better with a diversity patch at each end with the power level adjusted for a reasonable signal overlap in the middle.

As always, only a survey can tell you exactly what layout, antenna, and power levels would be "best" for that specific environment.

Good Luck

Scott

joeldc · ‎01-17-2008

Thanks Scott. Following your advice, we will be using patch antennas at both ends of the hallway. Did a survey and the patch will work out fine for what we need.

Thanks again for the advice.