Achievable Rates for Four-Dimensional Coded Modulation with a Bit-Wise Receiver
arXiv:1310.4149 · doi:10.1364/OFC.2014.M2C.1
Abstract
We study achievable rates for four-dimensional (4D) constellations for spectrally efficient optical systems based on a (suboptimal) bit-wise receiver. We show that PM-QPSK outperforms the best 4D constellation designed for uncoded transmission by approximately 1 dB. Numerical results using LDPC codes validate the analysis.