682 Mbit/s phosphorescent white LED visible light communications utilizing analog equalized 16QAM-OFDM modulation without blue filter

In this paper, a 682 Mbit/s phosphorescent white LED visible light communication (VLC) system utilizing 16-quadrature-amplitude-modulation orthogonal frequency division multiplexing (16QAM-OFDM) modulation based on analog equalizers without blue Biter is firstly experimentally demonstrated. The 3-dB bandwidth of white channel VLC link is enhanced from 3 to 143 MHz by using proposed optimal analog equalizers. On the basis of equalized modulation bandwidth, the maxim transmission data rate of 682 Mbit/s based on 16QAM-OFDM modulation could be achieved at the distance of 1 m and the resultant bit-error-ratio (BER) is 2.5 x 10(-3). The VLC link also could be operated at illumination level of similar to 1000 lx with data rate of 520 Mbit/s and the BER is 3.76 x 10(-3). All the BERs are below the forward-error-correction (EEC) limit 3.8 x 10(-3). The results show that analog equalizers could be used in 16QAM-OFDM VLC system. In addition, our transmitter and receiver modules are with compact size. The proposed VLC link without blue filter provides a solution for high-speed low-complexity VLC application based on OFDM modulation. (C) 2015 Elsevier B.V. All rights reserved.