I'm studying the example packet_tx
in /usr/local/share/gnuradio/examples/digital/packet. I have some questions regarding the process of packet transmission and the flow graph.
Why burst shaper block is needed? How do its parameters affect tx/rx?
Why polyphase arbitrary resampler block is needed? How do its parameters affect tx/rx?
are generated at the host at fixed intervals with variable length in a
range. What parameters are passed to the USRP to control the actual rate
of transmission? Or this is not controlled explicitly by the flowgraph,
so the USRP just transmits at whatever rate it sees suitable. Is it the sample rate of USRP sink?
the flow graph, the process to generate baseband symbols is clear. How
the modulating pulse is generated and how it is multiplied with the baseband symbols are not clear to me. Is it achieved by
the polyphase arbitrary resampler block? In digital communication
textbooks, the baseband modulating pulse is a continuous waveform. If
generated in digital system, like using GNU Radio in a computer, how to
do it then?