Power efficiency and the ability to high-speed modulation LEDs make them a suitable option as a transmitter in optical wireless communications. A special type of VLC system is OCC systems whose receiver is an imaging sensor. Some challenges of such systems are the low data transmission rate and the light flickering. Due to the presence of color filters in these sensors, the data transmission rate in OCC systems can be increased by using RGB LED and WDM. In this article, we were able to modulate the RGB LED with a frequency many times higher than the frame rate of the camera and prevent light flickering prospect from human eye using one of the under-sampled modulation methods called UPSOOK. On the other hand, using RGB LED, we send three strings of data in parallel to increase the data transmission rate.