Hello,
I’m trying to understand the relationship between the debug.tx_power parameter and the ant1.ch9.ref_frame0.tx_power_index settings in the calibration file of the QM35825 SoC.
From my understanding, debug.tx_power is the value used to ensure UWB regulations compliance when operating in Continuous Wave mode with a BW of 1 MHz.
Is the debug.tx_power value directly equivalent to the value that should be configured in antX.ch9.ref_frame0.tx_power_index (and others)?
Or is there some conversion, scaling, or other relationship between these two parameters?
So that, if I determine a compliant TX power using debug.tx_power, I can use the same numeric value for the tx_power_index fields - or are they mapped differently internally?
Thanks in advance for any clarification.
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The debug.tx_power value is not equivalent to the ant1.ch9.ref_frame0.tx_power_index.
In normal mode, ant1.ch9.ref_frame0.tx_power_index adjusts tx power by 0.25dB per unit with 0 being the maximum.
In debug mode, you have control of debug.tx_power, debug.pa_enabled and debug.pll_bias_trim. In this case there is no linear relationship.
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Thank You @Matthias.
We would like to rely on the DWM3001CDK for the other counterparts: which value should I set on the ant0.ch9.ref_frame0.tx_power_index to target the maximum transmit power that still complies with FCC regulations?
I’ve noticed, by using LISTCAL, slightly different calibration values on two different samples purchased at different times (in one case, the value was 0x1A, in another it was 0x19, both close values), but in general the tx power is reduced by more than 6dB w.r.t. the maximum value.
Thanks in advance.
The modules are factory calibrated for tx power and antenna delay, with the values stored in OTP memory. The value can differ between devices.
If you have changed the settings, the RESTORE command for the CLI FW (or reset_calibration python script for UCI FW) will restore calibrated values form OTP.
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