Error detecting/correcting activity information

matrix Gmatrix H
23 28  0
 2 16  5
17 16 18
17  3 18
22 20  3
17 19 16 10 25
15 11  3 14 15
Encode: msg="cut", corresponding vector $m = \left[ \begin{array}{c} 2\\ 20\\ 19 \end{array} \right]$, encode as $b$, where $b = G\cdot m$.
Decode: receive $b$. If there were no errors in transmission, we need to solve $G\cdot m = b$ for $m$. We know how to solve these kinds of systems!

Detect Errors: receive $b$. Compute $H\cdot b$. If there were no errors, this would give the zero vector. If there are errors, but in no more than two of the five positions, you are guaranteed that $H\cdot b \neq 0$

Modular tools

Ring: integers mod

Modular Gaussian Elimination Tool

Input matrix Operations Output matrix





	    

Convenient modular calculator