I have a few questions, but they mostly come down to: What is the data file format when using a file as a signal source?
==================================================================== >From http://www.nd.edu/~jnl/sdr/docs/tutorials/9.html#tth_sEc3.3 2.5 File sources Block: gr.file_source Usage: gr.file_source ( size_t itemsize, const char * filename, bool repeat ) Notes: gr.file_source reads the data stream from a file. The name of the file is specified by filename. The first argument itemsize determines the data type of the stream, such as gr_complex, float, unsigned char. The argument repeat decides whether the data in the file is sent repeatedly. As an example, we can use the block in this way in Python: src = gr.file_source (gr.sizeof_char, "/home/dshen/payload.dat", TRUE) ==================================================================== Question #1: What is the syntax for the itemsize argument? Since the example doesn't use one of the data types mentioned, it is hard to tell what the syntax is supposed to be. For instance, if I want to use gr_complex, do I specify gr.sizeof_gr_complex? If I want to use unsigned char, is it "gr_sizeof_unsigned_char" so as to eliminate the space? Question #2: What are all of the options for the itemsize argument? It lists "gr_complex", "float", and "unsigned char" yet the example uses one that is not in the list. Are there others? Question #3: Does the data file format for transmitting match the data file format when receiving? Can I take a file that is recorded, say using receive_file_c.py (may not have the file name exactly correct) and use that as a source without modification? If so, what does it mean to use IQ pairs as input data? What does the USRP do with them? If I use a data size of "gr_sizeof_float" does that mean that my data file should consist of a list of floating point values stored as IEEE single precision values where each value represents a time-sampled baseband data point? Thanks. _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
