Omni vs. Sector on AP

First off thanks for everyones help so far, we have a backhaul and a AP in place now to do some testing. We used a Cyclone Omni for the 900 AP we put up and was able to connect 8.6 miles away last night with the SM about 6 feet off the ground.

My question really is about the performance diffrences between an Omni and say 120 deg sector antenna. Would we be able to see greater distances if we went to 120 deg antenna and 3 AP’s? How about 60 deg? We have virtually no noise floor up here so interference is not a problem at this time, I know if we put the Omni too hard we will run into self interference problems eventually. We want to serve rural customers very well and whatever we can do to acheive the maximum possible distance is ok even if it means two more AP’s.

Thanks,
Ben

Personally we install the Cyclone 5.7Ghz AP’s in our new questionable deployments.

When the subscriber base gets to a point we can justify the sectorized AP’s we migrate to them.

What I have noticed is yes you can achieve greater distances with the sectorized AP’s, and also the RSSI, and Jitter levels are considerably better also on the SM’s.

–SDH

I think it all depends on the situation. We have over 70 subscribers off of an MTI wireless edge omni antenna and are able to achieve distances of 20+ miles under the right conditions (adequate height, line of sight, etc). I generally try to keep my connections shorter than 15 miles, however.

We have used omni antennas in the past… worked great for a smaller customer base and low noise floor… the higher the cust base the further SMs seemed to fall off (even after adjusting the power levels on the closer SMs)

Then came TXDOT with their FQ hopping nightmares and my omni was almost useless… had to switch out to HPOL 120 degree Sectors and everything is peachy… I have done away with all the omnis except 2 and they are scheduled for next month… If you are just starting omni is fine… keep in mind that you will have to change… ??? better to start out with the sectors??? Only you can make that call.

Good Luck.

May the RF gods look kindly on you!!!

CM

As mentioned, the issue with an omni is that is can pick up noise and interference from every direction, so the overall noise floor as seen by the AP receiver is higher.

Sector antennas offer off-axis rejection, and improve Rx sensitivity. Additionally you can get a little more power into a given sector that you can with an omni.

Obviously the cost is 3X AP’s and 3X $700 antennas vs 1 AP and 1 $700 antenna.

Two factors should be considered - sales and engineering.

From a sales standpoint, if you think you will be able to get enough subscribers to justify the cost of 3X AP’s, you should do it. If you want to grow organically through sales, best to start with the AP and 1 omni.

From the engineering standpoint, if you have issues with noise in your area, the sectors are going to give you more flexibility in dealing with interference, and more performance.