The maximum cable distance from antenna and Cisco 1200 series.

[networker.br]

Hello all!

I?m using the Cisco 1200 Access Points Series with two 2.2dBi dipole antennas. I have read the installation guide for that Access Points and that can be installed with the antennas in separated places. But this guide didn't mention the maximum distance for the antenna cable...

Somebody here can say me this maximum distance?

Had somebody here made this kind of antenna installation with cable?

Thanks.

[scottmac]

You can go ~150-200feet, maybe longer with the right kind of cable, as long as you compensate with the right antennas & power levels.

Remember though, that the AP, cables, and antennas are a system. Even very low-loss cabling, perfectly terminated will diminish the signal considerably at long distances.

Also remember that using two antennas is for the purpose of "diversity" within the same area ... not as a split system where one antenna covers one side of a building and the other antenna covers the other side of the building .... both antennas must "see" the same area.

Good Luck

Scott

[Matthew Bryant]

My rule of thumb is use as little antenna cable as possible. The longer the cable, the less signal strength you will get. It is better to run your network cable longer and place the access point where you need it. Use the PoE and that way you only have to run 1 cable.

Also, if you are running diversity, you need to keep the antennas spaced about the same distance as the connectors on the access point itself.

[sentekincan]

As mentioned by ScottMac, do not think you can cover two large areas with two antennas. The purpose of two antennas is, as Scottsaid, to provide diversity, meaning when the same signal reaches to both antennas at different times due to one signal bouncing around and reflecting from other surfaces access point makes a selection between two antennas on the basis of signal strength. Reflected signal has more loses therefore is weaker. In short AP accepts the signal only from one antenna at a time. I wouldn't use cables longer than 10 feet, just move access point closer to area you want to cover.

[scottmac]

Oh Yeah!, I absolutely agree on "shorter is way better"

...

Given any chance / choice at all, I'd try to keep the cable length under 25 feet. If the option is available for a NEMA cabinet to get the cable shorter, I'd probably do that too.

Since it's good practice to use a chunk of fiber optic cabling between the external stuff and the inside network, you may as well put the AP as close to the antennas as possible and convert the copper to fiber for the long haul.

You get some lightning protection (at least you won't smoke all of the systems sitting on your LAN) and better signal strength (and probably signal quality too).

For something like a 200' run, if forced to do it (we're talking "gun to the head" forced here), I'd probably be looking for something like Andrew LDF4-50 1/2" Heliax with probably a weeeeee bit O' amp tossed in for good measure.

That would also imply that the system would also have to be re-certified, because of the non-standard components ...and a pretty good budget to boot.

Sometimes you gotta do what you gotta do.

FWIW

Scott