Transformed code

This week I run the program and tried to get a table of threshold. At the beginning, I run into a problem with the transformed generating matrix and parity matrix. As they both are generated using algorithms for general matrix, it turns out to be a problem with the binary message.  I would like to solve it by pojecting the matrix into F(2) field, but in mat lab it is problematic. So I just used Gussian elimination to get the generating matrix from parity matrix. From that, I proved that the parity matrix is full rank and there is a single unique translating matrix between the information bits and parity bits. 

Decoder algorithm 20140917

Dual decoder algorithm:
1)Combine two parity matrix together to make a new bigger one. using bit-flipping algorithm to decode new codeword.
2) use two parity matrix separate and combine information bits in each iteration

Dual Decoder results

Update results: 2014-09-10

Ideal density evolution analysis for LDPC(3,6) codes under Binary Erasure Channel. 

Evolution of erasure rate during decoding process for single decoder 1 and 2.

 Evolution of erasure rate of dual decoder.

Next step, performance analysis of dual LDPC decoder.

List of Understanding

List of my understanding:

1. Decoding process:  Message passing algorithm
2. Density evolution