Abstract—Light fidelity (LiFi) is a means of high speed wireless data transmission along with room illumination. As a data encoder for LiFi, different variants of orthogonal frequency division multiplexing (OFDM) such as asymmetrically clipped optical OFDM (ACO-OFDM), asymmetrically clipped DC biased optical OFDM (ADO-OFDM) and asymmetrically and symmetrically clipped optical OFDM (ASCO-OFDM) have been considered. This paper provides a framework using pulse-width modulation (PWM) for dimming control of ASCO-OFDM based LiFi. In this framework, the generated ASCO-OFDM signal in the electrical domain is multiplied with the PWM signal, and the resultant signal is converted to the optical signal by optical modulators. The pulse width of the PWM based ASCO-OFDM signal is varied accordance with the dimming or brightness level. Next, the bit error rate (BER) performance is evaluated for PWM based ASCO-OFDM. Finally, results show that with PWM dimming, ASCO-OFDM is more electrical power efficient than others for a given data rate. Results indicate that for low data rates, both ASCO-OFDM and ACO-OFDM, and for higher data rates, ASCO-OFDM and ADO-OFDM are good choices in terms of optical power efficiency. Moreover, 4-QAM ASCO-OFDM system ensures low BER even for large dimming or lower signal power level.
Index Terms—Bandwidth, bit error rate, LiFi, PWM, ASCO-1OFDM, data encoder, dimming.
The authors are with the Institute of Information and Communication Technology (IICT), Bangladesh University of Engineering and Technology (BUET), Dhaka-1000, Bangladesh (e-mail: rubaiyat97@yahoo.com)
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Cite: Shahfida Amjad Munni, Rashed Islam, and M. Rubaiyat Hossain Mondal, "Performance Evaluation of ASCO-OFDM Based LiFi," International Journal of Future Computer and Communication vol. 9, no. 2, pp. 33-39, 2020.
Copyright © 2020 by the authors. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
(CC BY 4.0).
