Telefonaktiebolaget LM Ericsson (publ)
INFORMATION DECODER FOR POLAR CODES

Abstract:

There is provided mechanisms for decoding an encoded sequence into a decoded sequence. A method is performed by an information decoder. The method comprises obtaining a channel output. The channel output represents the encoded sequence as passed through a communications channel. The encoded sequence has been encoded using a polar code. The polar code is representable by a code diagram. The method comprises successively decoding the channel output into the decoded sequence by traversing the code diagram. The method comprises, whilst traversing the code diagram, determining a bit score term for each potential decoding decision on one or more bits being decoded. The method comprises, whilst traversing the code diagram, adding an adjustment term to each bit score term to form a candidate score for said each potential decoding decision. The successive decoding is repeated until all bits of the channel output have been decoded, resulting in at least two candidate decoded sequences. The method comprises discarding all but one of the at least two candidate decoded sequences, resulting in one single decoded sequence.