90 mbps with PTP radio 650, a distance of 30 km

Hello how are you friend cambium all forums.

Here I will share cambium PTP 650 radio installation with air distance of 30 km, from the installation of a total of up to 90 mbps tx rx with signal -63, please friends in this forum admin if this result is good or Keith beg enlightenment.

Here are the results of the PTP 650 setup in this blog

Setup Wireless Cambium PTP 650,30 KM Point To Point Wireless Backhaul

I wait for a reply from your friends and admin this forum

 i think this very normal because you running the 125 mbits lite version. if you upgrade to full 450 mbits licence version, you will have at least 225mbits and maybe more.

Thanks for the link to your blog.

It's normally useful to see the LINKPlanner file for a PTP link, and in this case we don't know if the links has any obstructions. The PTP 650 units are reporting a Link Loss of about 145.3 dB. If we work in dB, the measured Link Loss is the difference between the transmit power and the receive power, plus the antenna gain at each end, like this:

24 - (-62.3) + 30 + 29 = 145.3 dB.

We can find the expected basic loss of a line of sight link from this formula:


For 5.8 GHz and 30.7 km, the expected line-of-sight loss is 137.5 dB. This is about 8 dB lower than the measured Link Loss. This 8 dB discrepancy could be due to:

  • Obstructions within the Fresnel zone of the link
  • Actual antenna gain lower than 30 dBi or 29 dBi
  • RF feeder loss in the installation but not entered into the PTP 650
  • Alignment error in the antennas

Are any of these likely explanations? Can you share the LINKPLanner predictions with us?

As the previous contributor pointed out, this link has the Lite capacity license. The aggregate capacity at present is 102 Mbit/s. If you upgrade to the Full capacity license, the link capacity will increase to about 360 Mbit/s.