A different view on Maximum Radio Tx Power

We often heard people say which radio has the highest Tx power, since QPSK always give the highest power, so what people really say is what is the maximum Tx power of a radio working at QPSK mode.

But how many links really works on QPSK mode? In most of the link deployed today, radio works on 256QAM or even higher, so it is more critical to undertsand what is the Tx power on higher modulation mode. 

Here is an example between PTP820 and PTP800.

  Maximum Tx Power
@11 GHz PTP820 PTP800
2048 QAM 21 n/a
1024 QAM Strong 23 n/a
1024 QAM Light 23 n/a
512 QAM 24 n/a
256 QAM 25 19
128 QAM 25 21
64 QAM 25 21
32 QAM 25 26
16 QAM 26 26
8 PSK 27 n/a
QPSK 27 28

You can see PTP800 has higher power on QPSK, 1 dB better than PTP820. But @256 QAM, the PTP820 is 6 dB better than PTP800.

So which radio you think has higher power for you?



i would also to say that the important figure it is the system gain (in each modulations), it reppresent even better than PTx the quality of the product prefromances

this is my opinion

Dear ,

Can you share us maximum transmition Power for radio 820S on  7 & 23 Ghz ?

You recomend to set TX power manualy or Enable adaptive TX power mode ?

  Maximum Tx Power
  PTP820S - 23 Ghz PTP820S - 7 Ghz
2048 QAM    
1024 QAM Strong    
1024 QAM Light    
512 QAM    
256 QAM    
128 QAM    
64 QAM    
32 QAM    
16 QAM    
8 PSK    


Please see the User Guide, Technical Description, and Installation Guide documents here: https://support.cambiumnetworks.com/files/ptp820/

These are free for you to download and use!

The information you've asked for is on page 7-12 of the PTP 820S Technical Description document.

This document also contains much information about transmit power, power control, and power control during adaptive coding and modulation.

I hope this helps!


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