METHOD FOR SOFT-DECISION DECODING SYSTEMATIC BLOCK CODES Russian patent published in 2012 - IPC H03M13/05 H03M13/45 H04L1/20 

FIELD: information technology.

SUBSTANCE: for all resolved code combinations of a systematic (n,k)-code, based on f most significant bits thereof, the cluster number is determined, the value of f lying in the range 1<f≤k/2. Vector V is obtained and the accuracy of receiving the cluster number is estimated based on reliability gradations and the parity bit. In case of a positive solution, the (n-f,k-f)-code is then processed using ordered statistics by first creating a recourse vector W_yk by multiplying f bits by the first f rows of the code generating matrix G and temporary removal therefrom of cluster bits, after which vector W_yk is subtracted from vector V, for which cluster bits are also neglected, while assigning the least significant bit of the newly formed vector V_yr the lowest reliability gradation estimate. The remaining symbols arranged in descending order of their estimates. The error vector E for the shortened code is found using an equivalent code and after subtraction thereof, the decoder performs bitwise summation of vectors W_yk, V_yk and E, forming the transferred vector by repositioning the most significant bits of the cluster number, where is parity check of the cluster number is not performed, the decoder inverts the most unreliable bit from the checked bits.

EFFECT: high decoding speed and reliability of received information.

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