below is an email I had written to Josh B., but I just saw his
and realized he might not get time to reply at the earliest, so I am
forwarding at this list as well, so I can get all the help that I can.
I am a BSc electrical engineering student, in my final year. As part of
senior year project, I am working on co-operative communication using
boards. I have downloaded GnuRadio+Drivers, and read many tutorials,
your webpages, and other related information.
My supervisor insists that I use discrete blocks, instead of already
combined blocks (for certain modulation schemes, like qpsk etc). I am
working on that, however I have particularly no idea as to what a block
needs (like input), what it does to the output, and what each parameter
does. I have tired visiting the C code (its all too messy for me to
understand). I have visited examples as well, but no luck.
Here is what I am planning. I am thinking of writing my own Fortran
(we are a team of 4 so yes that is possible) and integrating that with
python; NumPy and then use that to connect with other basic blocks.
tell me if that will work (as in how much efficient would that be), and
whether there is a way round understanding the blocks.
Let me give you an example:
Our supervisor says, that given a data source of bits
1,1,1,1,1,0,1,0,1,0,0,1,0,1,0 for QPSK we first get the data to 2bits
symbol and then calculate its phase (map encoder) and then for
decoding we get differential decoder (which is basically just adding the
previous phase to the current phase) and then have it in I and Q form,
followed by pulseshaping.
Now I have read the API doxygen, the Simple GNU Radio User Manual, and I
cannot relate clearly as to what for example gr.map_bb() block does, or
is the differential encoder using y[k]=y[k-1]+x[k]%M (like why is there
mod in it ? ). Moreover, for a me a discrete pulseshaping filter would
kronecker delta pulses at its inputs and then have the pulse made around
the delta pulses as its output, but even that i donot understand.
Furthermore, how will use the demodulation block to determine the signal
using 'nearest distance metri
We are okay in making our own Fortran blocks and working, but we need to
sure. And would really like if we can find some book/manual to
on what convention was the blocks already existing made, etc, so we use
most of the existing work done.
I know you are busy person, and I am not sure, if you will even get time
read or reply to our email at the earliest (as we need to get to our
supervisor, at the earliest with our weekly progress) but please do help
us, or refere to someone else.
Thank you for your time,