Hello,
I have some problems with spurs in ubx-160 daughterboard with USRP X310. Interesting thing.
I transmit in Gnuradio simple signal source of cosine wave in frequency 1003MHz with Gain=15dB and connect the USRP to spectrum analyzer.
I can see the signal in 1003MHz in +8dBm as expected, but why do I see spur in 1003.006MHz (6KHz offset) at amplitude of (-40dBc) relative to the transmitted signal?
It can be seen when with small enough RBW and span values in the spectrum analyzer.
As far I understand from ubx 160 daughterboard RF information spec, the phase noise should be (-90dBc/Hz) -(-100dBc/Hz) and not that high as I get.
I don't know if my spur source is phase noise or some other spectral issue.
I'm well below the values of Tx max power and TX OIP3 of ubx-160.
Thanks a lot for any advice.