WITHDRAWN: Investigations on PON VLC OCDMA communications

Abstract

Green and smart buildings (SBs) are promising solutions to the fast-growing and ongoing urbanization around the globe and are the composition of huge services. The SB can acquire a tremendous amount of information and perform proper handling of many broadcasting residents accordingly. With the abrupt increase in the high-quality data transmission demands over long reach for the large number of connected residents in SBs, conventional data transmission techniques are inadequate to provide adequate services. Thus, in this paper, to improve the intelligence and reliability of SBs with high overall efficiency, cost-effectiveness, and security, a hybrid passive optical network (PON) and visible light communication (VLC) indoor broadcasting system is proposed. The bidirectional hybrid PON-VLC consists of integrated time and wavelength division multiplexing (TWDM) and wavelength division multiplexing (WDM) with optical code division multiplexing (OCDMA) PON with red green blue employed light emitting diodes (RGB LEDs) based VLC system. Seven OCDMA codes are utilized in the proposed work at a 10/2.5Gbps per channel transmission rate over hybrid fiber-VLC channels to strengthen the system performance. The simulation results show that the modified new zero cross-correlation (MNZCC) code outperforms other codes and provides a faithful 100km fiber length and 5m VLC range for 200 active residents. Moreover, VLC distance can be incremented up to 10m wireless range by increasing the received aperture diameter of 25cm. Also, the numerical analysis, as well as comparative performance, depicts the superiority of PON-VLC under the impact of impairments and noise in fiber-VLC link-based SBs.