DECODING OF LDPC CODES WITH SELECTIVE BIT-FLIPPING

摘要

The invention relates to a decoding method of low density parity check (LDPC) code,Gdbf (gradient descent bit reversal) type. In each decoding iteration, as long as the estimated word syndrome indicates an error (220230),Determine (270) a set of (f ̃ n) the most unreliable bits of the word, such as bits whose value of the local energy function (E ̃ n) is less than the threshold. The local energy value of the bit includes a first component proportional to the correlation between the bit and the corresponding sample of the observed signal,The second component represents the number of unverified stresses involved in the bit, and the third component is called the inertia component, which decreases with the reduction of the number of iterations (ℓ n) performed since the last inversion of the bit. The bits of the estimation words belonging to the set are inverted (280),Where appropriate, a new estimation word is provided in the next iteration with a predetermined probability.