Hello,
I'm attempting to use GNU Radio to parse data packets and not having much luck. I'm a beginner at both GNU Radio and Python, so I apologize if the solution to my issue seems obvious to everyone else.
Currently, I have a block of standalone Python code which uses the numpy.fromfile() command to read in data contained in a .bin file. My code basically grabs 10,000 samples from the file at a time and stores them in an array, does some processing on that array to find the data packets, and then moves on to another 10,000 samples until the entire file has been read. It works great; no problems whatsoever.
The goal is to be able to use the code with a USRP to receive data in real-time, which is where GNU Radio comes in and I'm getting stuck. My first task is to get the code working with GNU Radio using a file source to read in the same .bin file I mentioned earlier. When that works, I'll move on to using the USRP.
I've done all the GNU Radio Python tutorials and read absolutely
everything relevant I can find, but I'm having trouble understanding how
to receive 10,000 samples at a time from the file source. At this point I've been successful creating OOT Python blocks that work; I'm just not sure how to make them operate on chunks of data instead of one sample at a time.
I know GNU Radio has some support for packets, but I haven't been
successful using those modules. I think maybe the packets I'm trying to read aren't in the right format for them because they don't have a header? (My data packets have the form [Preamble with value 0xF1D90][60 data
bits][16 bit CRC].)
I'm not really sure where to go from here. I've tried to do as much research as I can, but as a newbie the GNU Radio documentation is pretty overwhelming and there's a lot of it that I don't understand. If anyone has any hints or advice, I'd really appreciate it. I'd love to learn from someone who has more experience with this than me.