A reduced-complexity multilevel coded modulation for APSK signaling

The amplitude and phase shift keying (APSK) signal has been adopted in the recent satellite communication standards such as DVB-S2 due to its peak-to-average power ratio (PAPR) property lower than the quadrature amplitude modulation (QAM). Unlike square QAM constellations that allow separate detection of in-phase and quadrature components (i.e., I-Q decomposition), the detection process for APSK is generally complex. This paper investigates the use of multilevel coding (MLC) together with multistage decoding (MSD) for APSK with particular emphasis on an introduction of a novel labeling that allows I-Q decomposition at the highest level, thereby significantly reducing the decoding complexity at the cost of slight performance degradation.