Light Fidelity (Li-Fi) is an advanced visible light communication (VLC) technic in which light emitting diodes (LEDs) are used for data transfer. In this article, a Li-Fi system using LED arrays is examined for indoor visible light communication. Lighting and data transmission simulations are made for return to zero on off keying (OOK-RZ) and 4-ary pulse position modulation (4-PPM) techniques with taking into account the optical path differences. Signal to noise ratios (SNRs) for both modulation techniques are calculated and used for comparison. Results of the simulations showed that data transmission rate up to 500 Mbps at FOV angle of 60° can be achieved for both modulation techniques.