Underwater wireless optical communication using a blue-light leaky feeder

A novel concept of using a leaky plastic optical fiber (POF) as the leaky feeder for underwater wireless optical communication (UWOC) is proposed and experimentally demonstrated. The leaky POF can potentially improve the UWOC coverage. Orthogonal frequency division multiplexing (OFDM) is employed in the demonstration to increase spectral efficiency and robustness to modal dispersion of the leaky POF with a large core. A bit rate of 224.61 Mb/s (net bit rate: 183.69 Mb/s) at the two discrete radiation points along a 10-m leaky POF feeder is achieved using 16-quadrature amplitude modulation (QAM)-OFDM modulation. Over a 30-cm underwater channel, the mean bit errors (BERs) measured at the two points are 3.37×10−5 and 3.35×10−3, respectively, which are below the FEC threshold of 3.8×10−3.