US 8,046,657 B2 · Decoding method and apparatus

Abstract

According to a method and apparatus taught herein, a decoding circuit and method decode linear block codes based on determining joint probabilities for one or more related subsets of bits in received data blocks. The use of joint probabilities enables faster and more reliable determination of received bits, meaning that, for example, joint probability decoding requires fewer decoding iterations than a comparable decoding process based on single-bit probabilities. As a non-limiting example, the decoding circuit and method taught herein provide advantageous operation with Low Density Parity Check (LDPC) codes, and can be incorporated in a variety of communication systems and devices, such as those associated with wireless communication networks.

Claims20

Dependent claims

A method of decoding a received data block encoded via a linear block code represented by a parity check matrix, the method comprising:

initializing joint probabilities of bit subsets in the received data block based on using the parity check matrix to identify the bit subsets as coupled bits in the received data block and calculating joint probability values for possible combinations of bit values in each bit subset according to corresponding soft values obtained from demodulating the received data block;
updating the joint probabilities based on the parity check matrix, by:
updating the joint probabilities as a function of all related combinations of the joint probabilities as indicated by the parity check matrix;
and
for one or more iterations, recalculating the joint probabilities and using the recalculated joint probabilities as initial values for a next iteration, and calculating final joint probabilities in a last iteration, wherein, in each intermediate iteration, recalculating the joint probabilities comprises, for each joint probability, excluding a corresponding one of the parity check equations from the recalculation to avoid a recalculation bias;
and
recovering encoded data from the received data block using the updated joint probabilities.

4 more elements

A decoding circuit configured to decode a received data block that is encoded via a linear block code represented by a parity check matrix, the decoding circuit comprising one or more processing circuits configured to:

initialize joint probabilities of bit subsets in the received data block by using the parity check matrix to identify the bit subsets as coupled bits in the received data block and calculating joint probability values for possible combinations of bit values in each bit subset according to corresponding soft values obtained from demodulating the received data block;
update the joint probabilities based on the parity check matrix, by:
updating the joint probabilities as a function of all related combinations of the joint probabilities as indicated by the parity check matrix;
and
for one or more iterations, recalculating the joint probabilities and using the recalculated joint probabilities as initial values for a next iteration, and calculating final joint probabilities in a last iteration, wherein the decoding circuit is configured to recalculate the joint probabilities in each of one or more intermediate iterations by, for each joint probability, excluding a corresponding one of the parity check equations from the recalculation to avoid a recalculation bias;
and
recover encoded data from the received data block using the updated joint probabilities.

4 more elements

Dependencies are inferred from the claim text.

Decoding method and apparatus

Life of this patent

Decoding method and apparatus

Life of this patent

Abstract

Claims20