Nonlinear Compensation Based on K-Means Clustering Algorithm for Nyquist PAM-4 VLC System

In visible light communication (VLC) systems, the nonlinear effects induced by many devices, such as the electrical amplifiers and optoelectronic devices, can significantly degrade the overall system performance. In this letter, to mitigate the nonlinear distortion effects, a clustering algorithm based on k-means is proposed and experimentally demonstrated in the VLC systems. The experimental results show that with the help of clustering algorithm to compensate the nonlinear effects, the bit error rate (BER) can be reduced from 2.4×10
^-1
to 3.6×10
^-3
. Moreover, the 400-Mbit/s Nyquist PAM-4 signal over 80-cm free space transmission can be successfully achieved.