Byte Reconfigurable LDPC Codec Design for High Performance Error Correction

-Error correction provides reliable information free from errors. BCH codes are widely used to perform error correction. However, in order to improve the reliability of error correction BCH codes have been replaced by Low Density Parity Check (LDPC) codes. LDPC codes are special class of error correcting codes widely used in communication and memory systems, due to its Shannon limit approaching performance and favorable structure. A sub class of LDPC codes, called Quasi-Cyclic (QC) LDPC codes is used as the error correcting code due to their structured Parity Check Matrices (PCM). These codes are flexible in the sense of supporting wide range of code lengths and rates. This work deals with an efficient byte reconfigurable, high throughput QC-LDPC codec design. The codec is able to support multiple bits with the constraint that size of the sub-parity matrix be multiples of eight. Error detection is done using modified majority logic decoding. Majority logic decoding is preferred as they can correct large number of errors having even as well as odd number of bit flips. This method reduces the decoding time by detecting errors up to four bit-flips in first three iterations of decoding. If no error is detected decoding terminates without completing rest of the iterations, thereby reducing the average decoding time.