08-14-2015 12:14 PM
I am new to LabVIEW and I wanted to test my USRP's and knowledge. Saddly, I am stuck even with the help of the RX and TX examples.
What I tried to do is create a dial tone, apply amplidtude modulation, and transmit on the TX side. For the RX side, I wanted to playback the demodulated dial tone. I beleive my TX side is correct, but I know I'm having issues with the RX.
Can anyone help me correct my errors?
08-17-2015 08:23 AM
I am using two NIusrp 2920's if that helps
08-17-2015 08:45 AM
Can anyone at least help me check to see if my AM RX/TX is correct? I can worry about the playback some other time.
08-17-2015 04:43 PM
Hi Kyosake,
It looks like you may not have the settings configured correctly to match one another. Make sure you're transmitting at the same Carrier Frequency that you're receiving. That will hopefully result in better data.
08-17-2015 06:50 PM
08-18-2015 02:52 PM
Kyosake,
Sorry, do you mean you set the carrier frequencies to be the same? I also have some other recommendations--
1) The IQ Sampling rate for the Tx VI should be equal to, if not higher than that of the Rx VI.
2) The Active Antenna should be TX1 and RX2 (they must be different antennas). This may be why the Coerced Carrier frequency looks so low, and is in fact much lower than the usable transmit range of the USRP
3) Move the Generate Sinewave VIs outside of the while loop.
4) Remove the Play Waveform VI from the while loop.
08-19-2015 08:48 AM
I am using two different USRP's on two computers. I dont know why the settings are not saving, but I set everything to match before TX/RX. Here are screen shots of updated VI's.
I moved the generators and play out of the loop like you said, but I am still not getting the proper demodulated signal on the reciving side.
TX
RX
08-19-2015 08:58 AM
I also tried moving a AM demodulate block outside of the loop, but that didnt make difference.
08-20-2015 09:13 AM
Hi Kyosake,
Thanks for the feedback. Have you created a service request for this by chance? My colleague is seemingly working on the same issue, so I'm guessing you did 🙂 We'll continue moving forward on the SR for the time being.
08-20-2015 10:49 AM
Yes, I did create a service request but I havent heard back from anyone in three days.