DNN-Based Demodulator/Post-equalizer and APSK Constellation Gain in Underwater Visible Light Communication System

This research combines APSK and DNN to solve the power limitation and nonlinearity problem in underwater visible light communication (UVLC) systems. DNN performs both the demodulation and equalization tasks. Compared with QAM plus conventional post-equalization method, APSK with DNN demodulator increases the usable Vpp range by at most 75% and reduces the minimum BER by more than 30%. It shows that DNN, especially complex-valued DNN, would be promising in UVLC as an integrated demodulator/post-equalizer.