Adaptive coded modulation over slow frequency-selective fading channels

We consider adaptive coded modulation for systems using QPSK/8PSK/16QAM constellations with a decision-feedback equalizer for slow frequency-selective fading channels. We investigate several potential channel-quality metrics that could be used to choose the correct coding and modulation scheme. We then present a threshold-adaptive algorithm that is especially useful for channels with a wide range of multipath profiles.