Decoding low-density parity-check codes with error-floor free over the AWGN channel

We propose a new soft decision decoding arrangement for LDPC codes over the AWGN channel with error-floor free. The iterative belief propagation decoder is used as the initial decoder with the iterative output conditioned prior to OSD decoding. Improved results are obtained to break the corresponding error floors caused by the stopping sets. The basis of the conditioning of the iterative output is explained with supporting analysis. Some practical examples of performance are presented for some well known LDPC codes and it is shown that the proposed decoder with OSD-i does not only produce better results than a stand-alone OSD-(i + 1) decoder with considerable reduction in decoder complexity, but also guarantees the error-floor free.