Coding and decoding
If m is a message word, then its code word c is given by c = mG (40)
HcT = 0 if and only if c is a code word (42)
Let r be an n-tuple where r = c+e (43)
The syndrome, s, is given by s = HrT
s = H(c+e)T = HcT+HeT = 0+HeT = HeT (44)
Decoding a received word r
- Compute the syndrome of r
- Decode the syndrome to produce e
- Compute c = r + e