[Discuss-gnuradio] transmission from usrp1 vs. usrp2

[Jordan J Riggs]

Hi,

I have code that modulates and transmits a DBPSK signal, and code that receives and processes the signal. Both sides work fine on the USRP1. Once I got my hands on some USRP2's, I modified my code such that it works on the new hardware. However, the spectral output of the USRP2 is decidedly different than the output of the USRP1. More specifically, the power distribution of various frequencies is different, and there is significantly more out-of-band power than with the USRP1. I am using RFX dboards. Given that I am transmitting the same, synthesized waveform stored on the hard disk, I would expect (nearly) identical spectral output, but broadened in response to the increase in sample rate. Is is possible that the filtering on the U2's DAC is less aggressive than that of the U1's? Is there some other obvious explanation?

Thanks,
Jordan