[Tinyos-help] Output Power levels CC2420
Rodolfo de Paz Alberola
rodolfo.depaz at cit.ie
Thu Feb 28 05:23:14 PST 2008
I calculated all values using cubic spline interpolation and obtained
the vectors of the txt file attached
Maybe It will be useful for your experiments with cc2420 radiochip ;-)
2008/2/27, bender.13 at wright.edu <bender.13 at wright.edu>:
This would certainly be helpful for my current work as well.
Now, I have a related question, Does anyone know what the
level on the CC2420 is?
i.e. If I just turn on the mote and start sending data, what is
power set to?
Rodolfo de Paz Alberola wrote:
>I am extending a micaz software emulator to support CC2420 and testing
>it with tinyos-2.x.
>When dealing with the Output Power Levels that cc2420 support in the
>TXCTRL.PA_LEVEL register, I found the problem that in data sheet they
>don't indicate all dBm values for the different 32 values, the only
>indicate the following:
>PA_LEVEL Pow (dBm)
>However using the cc2420 driver of tinyos-2.x I can set 32 different
>values, so I would like to know what happend if somebody set a for
>example PA_LEVEL = 21, which Pow(dBm) value should give the cc2420
>radiochip? anybody has the completely correspondence between levels and
>dBm? or even much better a equation to calculate them?
I once set PA_LEVEL = 5 accidentally in a radio measurement. Reception
quality was between setting 7 and 3, so it was apparently sending at
-20 dBm or so.
If you plot the above values, you get what looks like a square root
curve. Maybe it's OK to interpolate the other settings from a fitted
equation like P = a*sqrt(b*PA_LEVEL)+c.
-------------- next part --------------
PA_LEVEL 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Power (dBm) 0 -9.14E+02 -3.01E+03 -6.10E+03 -1.00E+04 -1.45E+04 -1.95E+04 -2.47E+04 -3.00E+04 -3.52E+04 -4.03E+04 -4.52E+04 -5.00E+04 -5.47E+04 -5.94E+04 -6.44E+04 -7.00E+04 -7.63E+04 -8.33E+04 -9.12E+04 -1.00E+05 -1.10E+05 -1.21E+05 -1.34E+05 -1.50E+05 -1.69E+05 -1.92E+05 -2.18E+05 -2.50E+05 -2.87E+05 -3.30E+05 -3.79E+05
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