TY - GEN
T1 - Wireless access test-bed through visible light and dimming compatible OFDM
AU - Mirvakili, Ali
AU - Koomson, Valencia J.
AU - Rahaim, Michael
AU - Elgala, Hany
AU - Little, Thomas D.C.
N1 - Publisher Copyright: © 2015 IEEE.
PY - 2015/6/17
Y1 - 2015/6/17
N2 - Visible light communications (VLC) technology has a potential to complement the RF wireless technology for indoor coverage. It promises concurrent illumination control and wireless data transmission capabilities. The potential of advanced multi-carrier modulation techniques, i.e. orthogonal frequency-division multiplexing (OFDM), introduces new challenges in the development of driver circuits. The reverse polarity optical OFDM (RPO-OFDM) is a recent approach to realize compatibility between the analog OFDM signal and the industry well-known pulse-width modulation (PWM) for dimming control. In this paper, we present the implementation of a wireless access test-bed through visible light and dimming compatible RPO-OFDM. A driver topology capable of driving a string of light-emitting diodes (LEDs) using a RPO-OFDM signal is proposed. The driver alleviates the nonlinearity of LEDs by proper biasing and maintaining a quasi-linear range of operation, i.e. minimizes the OFDM signal clipping. Using a software defined radio (SDR) platform for online modulation and demodulation, and a range of un-coded quadrature amplitude modulation (QAM) constellations, the experimentally obtained measurements demonstrate linear wide-range dimming while independently maintaining a bit-error performance below the forward error correction (FEC). Error free bit-error rate (BER) performance without symbol level equalization is obtained for binary phase shift keying (BPSK) and 4-QAM.
AB - Visible light communications (VLC) technology has a potential to complement the RF wireless technology for indoor coverage. It promises concurrent illumination control and wireless data transmission capabilities. The potential of advanced multi-carrier modulation techniques, i.e. orthogonal frequency-division multiplexing (OFDM), introduces new challenges in the development of driver circuits. The reverse polarity optical OFDM (RPO-OFDM) is a recent approach to realize compatibility between the analog OFDM signal and the industry well-known pulse-width modulation (PWM) for dimming control. In this paper, we present the implementation of a wireless access test-bed through visible light and dimming compatible RPO-OFDM. A driver topology capable of driving a string of light-emitting diodes (LEDs) using a RPO-OFDM signal is proposed. The driver alleviates the nonlinearity of LEDs by proper biasing and maintaining a quasi-linear range of operation, i.e. minimizes the OFDM signal clipping. Using a software defined radio (SDR) platform for online modulation and demodulation, and a range of un-coded quadrature amplitude modulation (QAM) constellations, the experimentally obtained measurements demonstrate linear wide-range dimming while independently maintaining a bit-error performance below the forward error correction (FEC). Error free bit-error rate (BER) performance without symbol level equalization is obtained for binary phase shift keying (BPSK) and 4-QAM.
KW - Dimming
KW - Intensity modulation
KW - Li-Fi
KW - PWM
KW - Reverse polarity optical OFDM
KW - VLC
KW - Visible light communications
UR - https://www.scopus.com/pages/publications/84938702862
U2 - 10.1109/WCNC.2015.7127820
DO - 10.1109/WCNC.2015.7127820
M3 - Conference contribution
T3 - 2015 IEEE Wireless Communications and Networking Conference, WCNC 2015
SP - 2268
EP - 2272
BT - 2015 IEEE Wireless Communications and Networking Conference, WCNC 2015
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2015 IEEE Wireless Communications and Networking Conference, WCNC 2015
Y2 - 9 March 2015 through 12 March 2015
ER -