I’m new to working on gnuradio (experience operating it with a usrp but
not
developing for it) so hopefully someone can help me out a bit here.
I want to write a module to compare different signals, looking for
differences in a few factors by passing some signal features over time
to a
python program. To do this, should I write a sync block in C++ (or
possibly multiple sync blocks) that will keep a long history and output
a
vector of the amalgamated features at some point to a python top block
for
evaluation?
For instance, I want to read the instantaneous phase, frequency, and
amplitude of a signal at the same time and output each of these to a
python
app, where I do some more work and then stop. I have looked through the
gnuradio utilities and don’t see many blocks/utilities that I could use
just to read something like instantaneous phase and pass that along.
Any help is appreciated, thanks.
Hey, just wondering if anyone could point in the right direction on just
how to write a block that will write out a feature like instantaneous
carrier phase to stdout. I’ve read all the tutorials on the website and
can’t seem to find anything that would fit this scenario. I tried going
through the code for some of the modulation blocks, but couldn’t see how
they received the phase data for something like phase modulation.
evaluation?
Hey Charles,
I’m not entirely clear on what your end goal is, but from your second
email
I immediately thought of
gr-digital/lib/digital_constellation_receiver_cb.cc
Check out the area surrounding line 72. It prints some stuff to stdout,
in
fact it prints the phase to stdout. If you change the VERBOSE_COSTAS to
1
so you can see it you will also need to make a couple of tweaks. The
print
statement is broken as is because sample is not known to
phase_error_tracking. (If someone wants me to write up a bug report on
the
tracker I can do that and submit a patch, but since it’s never used I
didn’t think anyone would care). My solution was to just change the
function signature to include sample.
In regard to your first email, if you’re looking to pass information
between a python program you might look into using gnuradio message
queues.
-Nathan