GNURadio + Dream


#1

OK- I’ve finagled the Dream code into giving me a file output from
transmitting and can even go into a FIFO and back into Dream receive-
the only problem is the dream decoder doesn’t seem to lock on to a
signal.

I have the code to receive off of the USRP into a FIFO (complements of
Mateo Campanella) which Dream can then supposedly use as an input…

There doesn’t seem to be any code to write out WAV file headers (on the
transmit side- the rx code does have the ability to decode to a wav
file) or anything, but I think the data may be raw data that you’d
presumably pipe to /dev/audio or something.

If say it is indeed a wav file, minus the header, theoretically how
would I take this output file and transmit it over the USRP (LF TX or
Basic TX) through a short rf patch cable into the basic RX or LF-RX and
back into Dream…

Similarly, if I took one of the Dream sample encoded files- which are in
fact wav audio- how would I transmit that?

I anxiously await the gnuradio originated code to do this sort of thing
more directly- but would appreciate any input anyone might have!

Thanks in advance!

-Brett


#2

Replying to myself here… I imported the data as raw using Audacity
under windows Signed 16 bit little endian and that seemed to result in
appropriate sounding (encoded) stereo audio. Using that as a source file
under windows does not yield results however. Still looking for more
information.


#3

Similarly, if I took one of the Dream sample encoded files- which are in
fact wav audio- how would I transmit that?

I anxiously await the gnuradio originated code to do this sort of thing
more directly- but would appreciate any input anyone might have!

We typically output raw data files. Sometimes float, sometimes short
(16-bits). Sox can be used to convert these to any other file you’re
likely to want. You could also rig up a variant of the file sink to do
wav files.

Matt