Low Density Parity Check (LDPC) codes were first introduced by Gallager [1] in 1962, but they were rarely used since implementing them in HW was impractical in 1960s. The value of LDPC codes was rediscovered by Mackay and Neal in 1996 [2]. Since then, LDPC codes have gained a lot of attention as channel codes for the 4G mobile communication due to their excellent error correction capability [3].