This paper presents the implementation of an IEEE standard-based Visible Light Communication (VLC) system using software defined radio (SDR) approach. Based on widely used SDR platform Universal Software Radio Peripheral (USRP) and visual programming language LabVIEW, we present a fully standard compliant implementation of all PHY I modes of the IEEE 802.15.7 standard. Rest of the equipments used in the experimental set-up are low cost and commercial off-the-shelf devices. We successfully demonstrate audio streaming through our software defined VLC system, which can transmit and receive data successfully up to 2 meters. We also present bit error rate results of all PHY I modes of IEEE 802.15.7 running on our VLC system, which operates at a distance of 1 meter.