Advertisement
Not a member of Pastebin yet?
Sign Up,
it unlocks many cool features!
- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
- Align LOs in the front-end (SBX/WBX + N-Series)
- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
- Using timed commands, multiple frontends can be tuned at a specific time.
- This timed-tuning ensures that the phase offsets between VCO/PLL chains
- will remain constant after each re-tune. See notes below:
- * There is a random phase offset between any two frontends
- * This phase offset is different for different LO frequencies
- * This phase offset remains constant after retuning
- * Due to divider, WBX phase offset will be randomly +/- 180 deg after re-tune
- * This phase offset will drift over time due to thermal and other characteristics
- * Periodic calibration will be necessary for phase-coherent applications
- Code snippet example, tuning with timed commands:
- ::
- //we will tune the frontends in 100ms from now
- uhd::time_spec_t cmd_time = usrp->get_time_now() + uhd::time_spec_t(0.1);
- //sets command time on all devices
- //the next commands are all timed
- usrp->set_command_time(cmd_time);
- //tune channel 0 and channel 1
- usrp->set_rx_freq(1.03e9, 0/*ch0*/);
- usrp->set_rx_freq(1.03e9, 1/*ch1*/);
- //end timed commands
- usrp->set_clear_time();
Advertisement
Add Comment
Please, Sign In to add comment
Advertisement