Hello everybody,
Many people say the Gnuradio operates in stream mode with the
flowgraph, but I am not clear about the stream mode, for it is too
abstract. Does anyone have a better way to understand it or interpret it
in plain words? And one thesis says,‘Gnu Radio is not designed to work
in packet mode, rather the scheduler is designed to operate on
continuous data stream’, so if I want to get precise-time control of the
data packet, what should I do? (What I recently do is to switch the
TX/RX using one antenna, I just make two top_blocks and switch them, the
problem is there is too much delay. If I want to send 5 seconds, I also
need to wait to 1.5 sec to make sure it successfully sent all the data)
Can I so lucky to reference someone’s information or get a hand
from you?
Thanks very much !
With stream tags you can precisely control timing of TX and RX, which
should allow you to do packet transmission.
Brief intro:
http://gnuradio.org/redmine/projects/gnuradio/wiki/BlocksCodingGuide#Stream-Tags
Also look at these examples (copied from
How to align Tx/Rx timestamps - GNU Radio - Ruby-Forum) :
A description of tags here:
http://gnuradio.org/cgit/gnuradio.git/tree/gr-uhd/include/gr_uhd_usrp_sink.h#n59
http://gnuradio.org/cgit/gnuradio.git/tree/gr-uhd/include/gr_uhd_usrp_source.h#n59
A tags demonstration:
http://gnuradio.org/cgit/gnuradio.git/tree/gr-uhd/examples/tags_demo.cc
Sean