#!/bin/sh # Example of decoding a (7,4) Hamming code using exhaustive enumeration and # probability propagation, with an Additive White Gaussian Noise channel with # noise standard deviation of 0.5, for which Eb/N0 = 5.44 dB. # # Testing is done by transmitting zero blocks, which is sufficient because # both the channel and the decoding procedure are symmetrical. Decoding is # done three, once minimizing block error probability, once minimizing # bit error probability, and once by up to 200 iterations of probability # propagation. set -x -e # Echo commands as they are executed; stop if an error occurs make-pchk ham7a.pchk 3 7 0:0 0:3 0:4 0:5 1:1 1:3 1:4 1:6 2:2 2:4 2:5 2:6 make-gen ham7a.pchk ham7a.gen dense transmit 7x100000 ham7a.rec 1 awgn 0.5 decode ham7a.pchk ham7a.rec ham7a.dec-blk awgn 0.5 enum-block ham7a.gen verify ham7a.pchk ham7a.dec-blk ham7a.gen decode ham7a.pchk ham7a.rec ham7a.dec-bit awgn 0.5 enum-bit ham7a.gen verify ham7a.pchk ham7a.dec-bit ham7a.gen decode ham7a.pchk ham7a.rec ham7a.dec-prp awgn 0.5 prprp 200 verify ham7a.pchk ham7a.dec-prp ham7a.gen