IQ Imbalance Tolerant Probabilistically Shaped Signals with Adaptive Constellation Referencing
Sameer Ahmad Mir, Lakshmi Narayanan Venkatasubramani, Liam P. Barry, Deepa Venkitesh · 2023
Probabilistic constellation shaping (PCS) can achieve information capacity scaling, even at a lower symbol rate. However, higher-order PCS is susceptible to nonideal system operations like IQ imbalance. In this abstract, we demonstrate the transmission of transmitter IQ imbalance tolerant probabilistic shaped 64QAM signal by employing a joint equalizer with reference constellation adaptation. The equalizer performs the carrier phase recovery and simultaneously adapts the ideal constellation to tolerate the IQ imbalance. We numerically investigate the algorithm's efficacy for PCS-64QAM signal for a range of imbalance and entropy values.