Comprehensive Study On The Influence Of LED Low-Level Modulation Toward Its Nonlinearity Within VLC System

Wong, Yong Xiang (2018) Comprehensive Study On The Influence Of LED Low-Level Modulation Toward Its Nonlinearity Within VLC System. Project Report. UTeM, Melaka, Malaysia. (Submitted)

Text (24 Pages) Comprehensive Study On The Influence Of LED Low-Level Modulation Toward Its Nonlinearity Within VLC System.pdf - Submitted Version Download (339kB)

Abstract

The degree project involved with implementation of the low-level modulation techniques toward the Visible Light Communication System (VLC) in order to investigate the effect of it toward the LED non-linearity effect. Two types of low-level modulation implemented in this work, the analogue low-level modulation and the digital low-level modulation. For analogue, amplitude modulation is used while for digital the amplitude shift key are used. Both techniques will be implement in the VLC system and comparison will be done between both modulation system and the normal VLC system. Three systems are designed and build. There are several experiments carried on these systems including the bright and dark test (environment test), distance test, angle test, current test and the power test. The environment test referring to the surrounding where the aim is to test the suitable environment for transmission. The distance test and angle test are used to test the coverage area of the system. The current and power test are used to test the non-linearity characteristics of the LED and result will be recorded and graph are plotted. For the bright and dark test, three systems are less disrupted by noise when it tested in dark surrounding. This is because during bright surrounding the surrounding light are creating noises that are affecting the system output. The range of the distance of the three systems are between 1 to 3 meters where the modulated systems are having longer distance. For transmission angle all three systems achieved 180 degrees. Lastly for the nonlinearity effect graph, digital and analogue modulation system are having a more linear graph than the normal VLC system. Generally, both digital and analogue modulation system are enhancing the transmission process but overall digital modulation are better because amplitude modulation are having more noise due to its characteristics.

Actions (login required)

View Item