Visible Light Communication With Input-Dependent Noise: Channel Estimation, Optimal Receiver Design and Performance Analysis

Abstract

This work investigates single-input single-output (SISO) visible light communication (VLC) when subject to signal-dependent shot noise (SDSN). The topics of discussion include channel estimation and data transmission, where in the former, we introduce both least square (LS) and maximum likelihood (ML) estimators. The Cramer-Rao lower bound (CRLB) of the channel estimation error is also derived. In terms of data transmission, we propose optimal and sub-optimal receiver designs and present their bit error rate (BER) performances. In specific, we derive a closed-form expression of the BER for the sub-optimal receiver and an approximated version for the optimal one. Our analysis indicates that the performance of the CRLB demonstrates no linear relationship with the SDSN, thermal noise, or the fading channel. On the other hand, SDSN has quite a severe effect on the channel estimation error bound, and as such, it can dramatically degrade the BER performance. Heightened performance degradation can also be explained by the joint effects of the channel estimation error and SDSN.