Omnidirectional on AP's

Has anyone put an omni on a 900 Mhz AP? Are there any range issues. We are considering a 10 dbi omni.

there is a company that has converted 900Mhz AP called Cyclone.
company is last mile gear.

The answer is yes, you will have limited range with an omni.

With the Maxrad 7dBi Panel on a 900MHz connectorized AP and either an integrated 900MHz or connectorized 900MHz with the 7dBi antenna we see 15miles+ when inside the 60dB coverage of the AP and clear LOS.

If you put a 10dBi omni on a 900Mz AP I am guessing that might expect to see 3-5 miles with perfect line of sight as long as the AP has good elevation and there is no foliage.

Jerry Richardson wrote:
The answer is yes, you will have limited range with an omni.

With the Maxrad 7dBi Panel on a 900MHz connectorized AP and either an integrated 900MHz or connectorized 900MHz with the 7dBi antenna we see 15miles+ when inside the 60dB coverage of the AP and clear LOS.

If you put a 10dBi omni on a 900Mz AP I am guessing that might expect to see 3-5 miles with perfect line of sight as long as the AP has good elevation and there is no foliage.


Actually you can calculate the maximum range with an omni under perfect conditions.

Perfect conditions:
Noise floor < -90 dBm
Perfect LOS

Transmitter 33 dBm = 9 dBi horizontally polarized omni on AP
Receiver -90 dBm receive sensitivity
Receiver 14 dBi Yagi antenna - 1 dB line losses
---------------------------------------------------------------------
Link budget = 33+90+13 = 136 dBm Total

Required fade margin 16 dB ~= 99.999% uptime with no interference.

133-16 = 117 dB available for path loss.

Go here:
http://www.firstmilewireless.com/calc_pathloss.html
Plug in 12 miles and 915 MHz.

The big variable you can change in this equation is the receive antenna. With a 14 dBi receive antenna you can do about 12 miles. With a 10 dBi integrated panel the best you are going to do is about 8 miles and with a 17.5 dBi Yagi the best you are going to do is about 15 miles.

-m-

I think the integrated antenna on 900 MHz is 12dBi.