Turbo decoder, operating method thereof, and electronic device including turbo decoder

A turbo decoder comprising:

• a first soft input soft output (SISO) decoder configured to receive systematic information, first parity information, and a first pre-log likelihood ratio (pre-LLR), and to output a first parity LLR obtained by calculating a log likelihood ratio (LLR) for the first parity information;
• an interleaver configured to interleave the systematic information;
• a second SISO decoder configured to receive an output of the first interleaver, second parity information, and a second pre-LLR, and to output a second parity LLR obtained by calculating an LLR for the second parity information;
• a first interference canceller configured to receive the first parity LLR from the first SISO decoder, receive the second parity LLR from the second SISO decoder, and calculate a first update parity LLR and a second update parity LLR;
• and
• a second interference canceller configured to receive the first parity LLR from the first SISO decoder, receive the second parity LLR from the second SISO decoder, and calculate a third update parity LLR and a fourth update parity LLR,
• wherein the turbo decoder uses the first through fourth update LLRs to derive decoded output data corresponding to the systematic information.

An operating method of a turbo decoder included in a reception device and comprising a first soft input soft output (SISO) decoder, a second SISO decoder, and an interference canceller, the operating method comprising:

• receiving, by the first SISO decoder, first parity information, first systematic information, and a first pre-log likelihood ratio (LLR);
• providing, to the interference canceller by the first SISO decoder, a first parity LLR generated by calculating an LLR for the first parity information;
• providing, to the interference canceller by the second SISO decoder, a second parity LLR generated by calculating an LLR for second parity information on the basis of received second parity information and second systematic information;
• obtaining a first extrinsic LLR by subtracting the first pre-LLR from a first post-LLR which is an output of the first SISO decoder;
• generating, by the interference canceller, a first update parity LLR and a second update parity LLR on the basis of the first parity LLR and the second parity LLR;
• and
• providing, by the interference canceller, the first update parity LLR to the first SISO decoder and providing the second update parity LLR to the second SISO decoder.