A new look of doping technique in BICM-ID

Doping technique was employed to remove the high error floor in conventional bit-interleaved coded modulation with iterative demapping and decoding (BICM-ID). This paper proposes a new look of the doping technique-BICM-ID with serial concatenated convolutional code (SCCC-BICM-ID). Unlike conventional doping decoding scheme which deems the doping decoder and the demapper as a whole doped demapper, we combine the doping code and the outer convolutional code together to form an SCCC, so that iterative demapping and decoding is performed between the demapper and the SCCC decoder. Extrinsic information transfer (EXIT) chart is used to analyze these two decoding schemes and reveals that they both can achieve near-capacity performance with no penalty of error floor. According to the results of EXIT analysis and BER simulations, SCCC-BICM-ID system can achieve the same or even better performance compared to the doping BICM-ID system with lower decoding complexity.