diff options
Diffstat (limited to 'octave/fdmdv_mod.m')
| -rw-r--r-- | octave/fdmdv_mod.m | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/octave/fdmdv_mod.m b/octave/fdmdv_mod.m new file mode 100644 index 0000000..3530cfe --- /dev/null +++ b/octave/fdmdv_mod.m @@ -0,0 +1,34 @@ +% fdmdv_mod.m +% +% Modulator function for FDMDV modem, uses test frames as input and +% outputs a raw file of 16 bit shorts at a sample rate of 8 kHz. +% +% Copyright David Rowe 2012 +% This program is distributed under the terms of the GNU General Public License +% Version 2 +% + +function tx_fdm = fdmdv_mod(rawfilename, nbits) + + fdmdv; % include modem code + f = fdmdv_init; + Nc = f.Nc; Nb = f.Nb; + + frames = floor(nbits/(Nc*Nb)) + tx_fdm = []; + gain = 1000; % Scale up to 16 bit shorts + prev_tx_symbols = ones(Nc+1,1); prev_tx_symbols(Nc+1) = 2; + + for i=1:frames + [tx_bits f] = get_test_bits(f,Nc*Nb); + [tx_symbols f] = bits_to_psk(f,prev_tx_symbols, tx_bits); + prev_tx_symbols = tx_symbols; + [tx_baseband f] = tx_filter(f, tx_symbols); + tx_fdm = [tx_fdm real(fdm_upconvert(f, tx_baseband))]; + end + + tx_fdm *= gain; + fout = fopen(rawfilename,"wb"); + fwrite(fout, tx_fdm, "short"); + fclose(fout); +endfunction |