US 5,968,198 A · Decoder utilizing soft information output to minimize error rates

Abstract

A coding system is disclosed wherein the receive side includes a decoder capable of producing, in addition to the hard information decoded output, either or both symbol and/or bit soft information values. For a certain information bit position, a value proportional to the joint probability that a received symbol and the set of all hypothesized transmitted codewords that led to the estimated or detected hard information output is calculated. The calculated probabilities with respect to plural codewords having a zero in that certain information bit position are compared to the calculated probabilities with respect to the plural codewords having a one in that certain information bit position. The result of the comparison provides an indication of whether the hard information output in that same information bit position is more likely a one or a zero. The output soft information values are further processed in comparison to a preset threshold, with instances exceeding the threshold triggering block rejections and/or retransmissions.

Claims31

Dependent claims

A decoding method, comprising the steps of:

comparing a received vector r with each one of a plurality of codewords y, each codeword having an associated hard information vector x;
selecting the codeword y closest to the received vector r;
outputting the hard information vector x corresponding to the selected codeword y;
and
determining a reliability vector s for the output hard information vector x, the reliability vector s determined for each symbol location of the hard information vector x, as a function of each of the plurality of codewords y and the received vector r.

2 more elements

A decoder, comprising:

means for comparing a received vector r with each one of a plurality of codewords y, each codeword having an associated hard information vector x, selecting the codeword y closest to the received vector r, and outputting the hard information vector x corresponding to the selected codeword y;
and
means for determining a reliability vector s for the output hard information vector x, the reliability vector s determined for each symbol location of the hard information vector x as a function of each of the plurality of codewords y and the received vector r.

Dependencies are inferred from the claim text.

Decoder utilizing soft information output to minimize error rates

Life of this patent

Decoder utilizing soft information output to minimize error rates

Life of this patent

Abstract

Claims31