US Patent 8656249 Multi-level LDPC layer decoder

Various embodiments of the present invention provide methods and apparatuses for multi-level layer decoding of non-binary LDPC codes. For example, an apparatus is disclosed for layer decoding of multi-level low density parity check encoded data. The apparatus includes a low density parity check decoder operable to perform layered decoding of a plurality of circulant submatrices from an H matrix. The apparatus also includes a parity check calculator connected to the low density parity check decoder, operable to detect whether a stopping criterion has been met in the low density parity check decoder. The low density parity check decoder is also operable to end a decoding operation at less than a maximum number of iterations when the stopping criterion is met.