875-Mb/s Asynchronous Bi-directional 64QAM-OFDM SCM-WDM Transmission over RGB-LED-based Visible Light Communication System

A practical indoor visible light communication system

“…Some schemes such as complex modulation, wavelength division multiplexing (WDM) and MIMO have to be used to increase data rates [3][4][5][6][7]. Discrete multitones (DMT) and orthogonal frequency division multiplexing (OFDM) have been found favor for higher data rates of VLC, because of the high Signal-to-noise ratio (SNR), low modulation bandwidth characteristics of typical illumination LED based systems.…”

“…A 1.5Gbit/s indoor VLC system based on RGB white LED with single channel, exploiting an optimized DMT modulation, has been reported [5]. Reference [6] experimentally proposed an asynchronous bi-directional VLC system based on subcarrier multiplexing (SCM) and WDM, reaching the gross data rates of 875Mb/s. In [6], the downlink used red and green color LEDs to transmit useful information and blue color LED was used for illumination, while blue color LED carry useful signals for uplink.…”

On the Role of Power Electronics in Visible Light Communication

“…c) The third possibility is to split the digital information into several sequences of bits (instead of one) and to modulate several carriers with these sequences [7,[12][13][14][15][16][17][18][19][20][21][22]. Also as an example, Fig.…”

“…Most of the existing literature focuses on the signal processing involved, modulations used and their implementations [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22], the modelling of LEDs [20] and some low-power, custom-made hardware for emitters and receivers [9,[23][24][25]. The bit rate provided by VLC systems is continuously increasing [26][27][28][29][30][31][32][33] thanks to the use of complex modulation and/or multiplexing schemes such as QAM [34], Wavelength Division Multiplexing (WDM) [32] and Orthogonal Frequency Division Multiplexing (OFDM) [7,[12][13][14][15][16][17][18][19][20][21][22].…”

“…The bit rate provided by VLC systems is continuously increasing [26][27][28][29][30][31][32][33] thanks to the use of complex modulation and/or multiplexing schemes such as QAM [34], Wavelength Division Multiplexing (WDM) [32] and Orthogonal Frequency Division Multiplexing (OFDM) [7,[12][13][14][15][16][17][18][19][20][21][22]. These schemes increase spectral efficiency (which means that higher bit rates can be achieved) and mitigate other problems, like the multipath issue.…”