Hi List, I'm transmitting a pure sinusoid of 50kHz using the tx_waveforms UHD example and receiving the same using rx_samples_to_file example. I'm using N210/WBXs for Tx and Rx at 250MHz, at 500 ksps, --ampl=1.0, buffer size of 200 at Tx, and 0 dB for Rx,Tx gain.
I plot the received file (the I stream, after de-interleaving the complex shorts) using gnuplot and here's what I see. The peak to peak amplitude is 40. The wave's dancing nicely about 0 and its a spectacular sine wave at almost precisely 50 kHz. But here's the catch: I can see this happening only after about sample # 8000 thereabouts in the graph. Before this, the wave starts out (at sample # 10 ) at 1400-1440 peak to peak and gradually makes its way down(maintaining its sinusoidal shape during the descent) to settle at -20 to +20 peak to peak. It takes 8000 samples for this to happen, or 8000*2us = 16ms. Why is this happening? Arya P.S. At Tx/Rx gains of 15 dB, same thing happens but the signal starts at around 1000-2000 p2p and settles at -500 to 500 at around sample #6000. _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
