Hello,
anyone knows what happened to antenna-gain in 6.46.8 or how to make it work again? It was working in 6.45.8 and most probably in 6.45.9,
it is not in 6.46.8, the option is missing totally - both in winbox and terminal.
thanks
antenna-gain is now a CLI-only parameter.
Why?
that’s unfortunate :-/ How do I display it? detail does not show it, I didn’t find it anywhere
/interface wireless set antenna-gain=x
one more thing
i’ve been asking multiple times about Spectral scan, i want that features to be implemented on 5 mhz
Seeing current antenna-gain value ?
Use CLI:
/ interface wireless export verbose
/ interface wireless print advanced
Spectral scan is function of wireless radio chip. Mikrotik uses the cheapest versions of the chip that simply can’t do it, no amount of software can fix that.
I assume because 1) most Mikrotik devices have fixed antennas (with corresponding gain) and 2) it is no longer required for “tx power abuse”, as tx power can be set manually.
Devices with fixed (built in) antenna should not allow gain changes. Gain is the property of the antenna, so why would you change it? This parameter is only so that you can specify what kind of external antenna you have connected.
Isn’t it also the only way to reduce TX Power? By specifying a higher antenna gain? Yes, there are situations where you might want to lower TX Power.
No, it is not. In advanced mode on your wireless interface you can specify TX Power. No need (anymore) to use the gain setting.
You can adjust Tx-power by selecting “all rates fixed” in Tx Power Mode and afterwards setting a lower Tx power.
“Antenna gain” It is not the only way, but it was the “better” and “easier” way to do it.
“Better” because it correctly calculates the max TX power for every MCS to comply with the EIRP emission requirements. (Higher MCS’es have broader RF sidelobes and need to transmit at a lower TX power). TX-power setting according to those “card rates” does not work with many devices. “All rates fixed” works but does not moderate for the MCS spectrum differences.
“Easier” because you do not need to do the math with the antenna gain. The current/default value is hidden quite deep even with CLI.
The GUI could at least have shown the antenna gain, and the corresponding max TX power (which is now in the status tab). Or could have added a “TX power DELTA” parameter, or that fuzzy “% power” of other brands (“fuzzy” because this is logarithmic).
And the “DELTA” is not a signed number, so cannot increase the TX power, just as the minimum antenna gain is prohibiting the setting of a higher TX power.
Changing tx-power-mode to all-rates-fixed and altering tx-power does nothing unless we also set frequency-mode to manual-txpower which isn’t allowed for the country selected that I’m currently in.
Atleast that’s what I get on a hAP ac2.
And changing the country to something else you wouldn’t be bounded by the reglementations of that country (max tx power and frequencies allowed), trusting the user to not break that.
So altering antenna gain was/is the only easy and “decent” way to decrease TX Power and still be bounded by reglementations.
Just my thoughts on this.
Your regulation forbids increasing power. If you use this setting to lower the power and you are operating within the legal allowed total EIRP, I don’t see why a certain mode would not be allowed to use
Altering “All rates fixed” power level is the wrong way to do this. That’s why there was “Card rates” option instead, but that stopped working with 802.11ac hardware.
Why is “All rates fixed” bad? Let me explain:
802.11 uses various modulations, from classic BPSK/QPSK to OFDM with QAM. Increasing modulation complexity requires more linearity in power amplifier. So it’s very important to follow hardware specifications on maximum power level for various modulations. If you don’t, signal will be distorted and it will actually worsen the SNR, produce unwanted interference outside of channel mask and it will make device non-compliant.
What antenna gain did it emulated the “Card rates” power option, where the antenna gain was subtracted from power levels at each modulation. So if by default you had 20dBm for 802.11b and 16dBm for 802.11n MCSx, it would decrease both proportionally.
But now, if you try to do the same with “All rates fixed” power, you are limited by maximum power level defined by most complex modulation. You can’t go above that otherwise signal gets distorted as described above. If you are lowering power by say 10dBm, this may not be an issue as you will be below even most complex modulation level. But if you just want to lower power output by a few dBm, you can’t.
Using same example with 20dBm/16dBm power levels, if I wanted to lower it by 2dBm, I can’t. If I set fixed power to 18dBm, higher MCS levels will be distorted and device will not be compliant and power levels at different modulations will be affected differently.
What most people really want is to enter simple value that lowers the gain proportionally for all modulations by a specified number. If I want 5dBm weaker signal, I just enter “5” and I get 5dBm less signal over all modulations and modes. Irregardless of regulation domain settings, MIMO chain settings, different radios and products and all the other mess, keeping things simple and always working.
What most people really want is to enter simple value that lowers the gain proportionally for all modulations by a specified number. If I want 5dBm weaker signal, I just enter “5” and I get 5dBm less signal over all modulations and modes. Irregardless of regulation domain settings, MIMO chain settings, different radios and products and all the other mess, keeping things simple and always working.
THIS! All rates fixed is NOT a good solution.
Yes!
Would it be possible to bring back Antenna Gain or something similar? I need a simple way to lower power.
+1!