Updating conflict solution for pipelined layered LDPC decoder

Due to the overlap of nonzero sub-matrices in the successive layers of check matrix, the pipeline process might introduce data updating conflict in pipelined layered LDPC decoder. A solution to solve this problem by adjusting the decoding order of layers in check matrix and nonzero sub-matrices in the same layer is proposed in this paper. Furthermore the corresponding fast algorithm is given. In term of hardware implementation, this method which can be achieved simply by changing the order of the corresponding data in the ROMs will not increase any extra hardware overhead. Experimental results show that due to fewer idle clocks even zero idle clock need to be inserted into decoding pipeline when using this solution, the decoding rate is improved effectively. More importantly, the method will not degrade the decoding performance for LDPC codes.