Hi Josh and others,
I have some more questions related to DUC/DDC cordic, USRP tuning
When an eob tag is issued, the DUC phase accumulator on transmit DSP
chain is reset. What about the DDC phase accumulator on receive DSP
chain? Does it reset at well? I am asking because I have seen that the
receive DSP chain and transmit DSP chain apply independent freq
corrections in order to tune to the desired center RX and TX
frequencies. In other words, is there any relation/binding between the
DUC cordic and DDC cordic? I hope two separate/independent phase
accumulators are used for DDC and DUC cordic’s but I want to verify.
What is the tuning granularity of RF front end? I can see from USRP
FAQ on gnuradio.org that it is 4MHz for RFX boards.
Is step size dependent on the daughterboard, mother board or both? I am
asking because when I set my USRP N200 to transmit at say 892MHz, I
observe the below values:
Actual RF freq: 892857142.847963 Hz
Actual DUC DSP freq: - 857142.847963 Hz
What does an RF frequency of 892857142.847963 tell about the step size
of RF front-end (which is RFX900)?
Thanks in anticipation,