III-nitride LEDs offer a solution for ultraviolet (UV) high-speed communication as a transmitter with high performance. This paper focuses on a transmitter with AlGaN/InGaN multi-quantum wells (MQWs) for UV communication. The transmitter is realized on a GaN-on-silicon platform by a double etching process. The emission region of the transmitter with a small area is beneficial for improving the data rate of UV communication. The emission peak keeps stable at 376.48 nm in the UVA band. The transmission with 300 Mbps is obtained in a UV communication system setup with on-off keying (OOK) modulation. We realize a digital signal transmission up to 760 Mbps by bit-loading discrete multi-audio (DMT) modulation.