Deep Learning-Assisted Index Estimator for Generalized LED Index Modulation OFDM in Visible Light Communication

Abstract

In this letter, we present the first attempt of active light-emitting diode (LED) indexes estimating for the generalized LED index modulation optical orthogonal frequency-division multiplexing (GLIM-OFDM) in visible light communication (VLC) system by using deep learning (DL). Instead of directly estimating the transmitted binary bit sequence with DL, the active LEDs at the transmitter are estimated to maintain acceptable complexity and improve the performance gain compared with those of previously proposed receivers. Particularly, a novel DL-based estimator termed index estimator-based deep neural network (IE-DNN) is proposed, which can employ three different DNN structures with fully connected layers (FCL) or convolution layers (CL) to recover the indexes of active LEDs in a GLIM-OFDM system. By using the received signal dataset generated in simulations, the IE-DNN is first trained offline to minimize the index error rate (IER); subsequently, the trained model is deployed for the active LED index estimation and signal demodulation of the GLIM-OFDM system. The simulation results show that the IE-DNN significantly improves the IER and bit error rate (BER) compared with those of conventional detectors with acceptable run time.

Performance Analysis of Dual-Hop Mixed Power Line Communication/Free-Space Optical Cooperative Systems

“…In the literature, various communication systems have considered integrating either PLC or FSO into either outdoor or indoor broadcasting communication. In [6], the performance of a mixed cooperative communication system between PLC and visible light communication [7,8] was evaluated, while a dual hop wireless-PLC mixed cooperative system. Furthermore, a mixed FSO-radio frequency relaying (RF) system was considered in [9] by using decoding and forwarding (DF) technique.…”

Hybrid Adaptive Bias OFDM-Based IM/DD Visible Light Communication System

“…Considerable research has applied OFDM technology to VLC. As we all know, the VLC requires non-negative and real OFDM signals, due to intensity modulated direct detection (IM/DD) is widely used in VLC systems [8][9][10]. In order to meet the requirement, several optical OFDM schemes have been proposed for IM/DD VLC systems.…”