Ahead-of-time stopping method of low complexity LDPC code weighting bit flipping decoding algorithm

Abstract

The invention discloses an ahead-of-time stopping method of a low complexity LDPC code weighting bit flipping decoding algorithm. The method includes the steps that S1, initializing is conducted; S2, the syndrome s is calculated through z, wherein the s={s1, ...sm, ...sM}= zH<T>, sm=mod(sigma n<A (m) zn, 2), the expression of the sm is shown in the specification; S3, when the s is equal to zero, iteration is stopped, and decoding output is z; when the s is not equal to zero, if k>=Kmax, decoding fails, and decoding is over; if k<Kmax and k=k+1, the flipping function {En, 1<=n<=N} of each information node is calculated; the maximum value (please see the specification for the formula) of the flipping function is solved, and if MAX<0, decoding is over; otherwise, the z is updated, and iteration continues. According to the ahead-of-time stopping method of the low complexity LDPC code weighting bit flipping decoding algorithm, after the flipping function {En, 1<=n<=N} of each information node is obtained through calculation, the maximum value of the flipping function is solved, if MAX<0, the iterative process is stopped directly, wherein the expression of the MAX is shown in the specification, and otherwise iteration still continues according to the original steps; the non-error correction frame decoding process can be discovered and stopped in time, waste of hardware resources is avoided, and decoding time delay is lowered. Simulation results show that under the condition that the bit error rate and the frame error rate basically remain unchanged, the average iterations of the weighting bit flipping decoding algorithm can be greatly decreased, and therefore the system time delay and the implementation complexity are lowered.

Description

technical field [0001] The invention relates to a low-complexity low-density parity check (Low density parity check, LDPC) code weighted bit-flip decoding algorithm method for stopping iterations in advance. Background technique [0002] Low density parity check (Low density parity check, LDPC) codes have important application prospects in the fields of mobile and deep space communication. As a class of linear block codes, LDPC codes are defined by their parity check matrix. There are many methods for constructing the check matrix, and two of the more common ones are: design based on Progressive Edge-Growth (PEG) algorithm, and point and line design based on Projective Geometry (PG). The two can be recorded as PEG-LDPC code and PG-LDPC code respectively. [0003] The sum-product algorithm based on belief propagation theory is a decoding algorithm with excellent performance for LDPC codes, but because of the large number of exponential and logarithmic operations involved in...

AI Technical Summary

Problems solved by technology

Since the decoding process of the sum-product algorithm is different from that of many existing WBF algorithms, the early iteration stopping method proposed for the sum-product algorithm is no longer applicable to the WBF algorithm.

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