This paper proposes the orthogonal and nonorthogonal schemes in the interference environments for visible light communication( VLC) systems. The proposed schemes pay attention to the case when different bit streams ...This paper proposes the orthogonal and nonorthogonal schemes in the interference environments for visible light communication( VLC) systems. The proposed schemes pay attention to the case when different bit streams from multiple cells are simultaneously transmitted, which consequently causes inter-cell interference( ICI) and greatly deteriorates the bit error rate( BER) and channel capacity performance of the system. The performance of the newdeveloped multi-cell system in indoor VLC systems is evaluated. The bipolar phase shift keying( BPSK) modulation scheme with orthogonal pulses( OPs) for multiple cells environments is employed to mitigate the ICI problem and improve the BER and channel capacity performances. Since the use of different OPs in each cell requires more number of OPs, which requires high bandwidth, OPs are reused at certain distances. Three different schemes, which are OPs,orthogonal and non-orthogonal pulses( NOP) reuse, are compared. This paper investigates the impact of using these schemes and compared their performances in the ICI environments. The BER and channel capacity using the proposed schemes are comprehensively examined. Simulation and theoretical results showthat the OPs schemes are more effective in the interference areas of the room and significantly outperform NOP.展开更多
基金The National High Technology Research and Development Program of China(863 Program)(No.2013AA013601)the National Natural Science Foundation of China(No.61223001)+6 种基金the Natural Science Foundation of Jiangsu Province(No.BK20140646)the Research Fund of National Mobile Communication Research Laboratory(No.2014A032014B032014B04)the Research Fund of Zhongxing Telecommunication Equipment Corporationthe Fundamental Research Funds of the Central Universities(No.2242014K40033)the United Creative Foundation of Jiangsu Province(No.BY2013095-1-18)
文摘This paper proposes the orthogonal and nonorthogonal schemes in the interference environments for visible light communication( VLC) systems. The proposed schemes pay attention to the case when different bit streams from multiple cells are simultaneously transmitted, which consequently causes inter-cell interference( ICI) and greatly deteriorates the bit error rate( BER) and channel capacity performance of the system. The performance of the newdeveloped multi-cell system in indoor VLC systems is evaluated. The bipolar phase shift keying( BPSK) modulation scheme with orthogonal pulses( OPs) for multiple cells environments is employed to mitigate the ICI problem and improve the BER and channel capacity performances. Since the use of different OPs in each cell requires more number of OPs, which requires high bandwidth, OPs are reused at certain distances. Three different schemes, which are OPs,orthogonal and non-orthogonal pulses( NOP) reuse, are compared. This paper investigates the impact of using these schemes and compared their performances in the ICI environments. The BER and channel capacity using the proposed schemes are comprehensively examined. Simulation and theoretical results showthat the OPs schemes are more effective in the interference areas of the room and significantly outperform NOP.