Visible Light Uplink Communication Using D-Shaped Side-Emitting Plastic Optical Fibers

A distributed visible light communication (VLC) uplink system employing a D-shaped side-emitting plastic optical fiber (POF) receiver is proposed. The D-shaped fiber is fabricated by truncating one side of a conventional circular POF, enabling enhanced lateral light coupling and increased received irradiance. To mitigate inter-symbol interference, a least mean squares (LMS) adaptive equalizer is implemented at the receiver. Experimental results obtained at symbol rates of 50 kbps, 500 kbps, 1 Mbps, and 5 Mbps show that the achievable transmission distance decreases with increasing symbol rate, and a maximum distance of 13 m is achieved at 50 kbps under 7% FEC limit. These results demonstrate the effectiveness of the proposed D-shaped side-emitting POF receiver combined with LMS equalization for enhancing distributed VLC uplinks.