|Subject:||Re: [Discuss-gnuradio] Editing usrp_spectrum_sense.py|
|Date:||Tue, 22 Mar 2016 21:10:38 +0100|
|User-agent:||Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0|
the physical power depends on your waveform. Generally, the power is always , which, thanks to Ohm's law () is . As you might know from the basics of electrical engineering, one can represent harmonic functions such as a voltage sine generated by a function generator as complex number with magnitude and phase , i.e. as ; notice that for the power consideration, you can omit the , it always having the magnitude 1. Use your math basics to find the average power by integrating over a period. For harmonic signals you'll find that if you set .
2. Moreover, am I supposed to connect the signal generator directly to the TX/RX port?If you can make sure your signal generator doesn't push more than -15dBm into the USRP, then sure. Otherwise, use a calibrated attenuator and adjust your measurement.
I don't know which signal generator you use, but most RF signal generators I know accept both, either voltage/amplitude or power as setting.
Also make sure your signal generator is set to 50Ohm impedance, if that is adjustable.
3. Finally, if that was the case, how do I observe the digital power on the USRP n210?Well, the magnitude of the imaginary and real part of the digital samples are proportional to the voltage on the I and Q input of the ADC... Soooo: Digital power is just I²+Q² = |s|², the magnitude squared.
All in all, these are pretty basic questions; we're constantly working on making GNU Radio more beginner-friendly, but to do that, we might at times need to refer people to adequate literature.
So: May I ask what background you come from?
PS: could you also try to keep the address@hidden mailing list at least in CC:? It's always better to ask the whole list instead of individual people. I might not always have the time...
On 22.03.2016 17:48, Fikrat Al-Kazimi wrote:
|[Prev in Thread]||Current Thread||[Next in Thread]|