Performance of Low Density Parity Check Codes as a Function of Actual and Assumed Noise Levels
David Mackay, Christopher P. Hesketh · Electronic Notes in Theoretical Computer Science · 2003
We investigate how sensitive Gallager's codes are, when decoded by the sum-product algorithm, to the assumed noise level. We have found a remarkably simple function that fits the empirical results as a function of the actual noise level at both high and low noise levels.