On the difficulty of bit-interleaved coded modulation fordifferentially encoded transmission over fading channels

摘要

The application of bit-interleaved coded modulation (BICM) incombination with differential encoding and non-coherent reception overflat fading channels is assessed. Since the labeling plays a centralrole for BICM we propose a suitable definition of Gray labeling fordifferentially encoded transmission. We show that for multiple symboldetection such a Gray labeling does not exist. Finally, we illustratethe consequences on the capacity by comparing BICM and an optimum codedmodulation scheme