UWOC performance based on single carrier frequency division multiplexing

Abstract Underwater optical communication (UWOC) systems require power-efficient designs to support battery-powered nodes that are difficult to recharge or maintain. The energy-efficient architecture of UWOC systems is essential for prolonging the lifespan of underwater optical wireless networks. Reducing transmission power and mitigating the peak-to-average power ratio (PAPR) can significantly lower overall energy consumption, thereby improving the operational lifetime and reliability in remote or deep-sea environments. In this work, single-carrier frequency-division multiplexing (SC-FDMA) has been proposed as a power-efficient system for UWOC due to its lower PAPR. The complementary cumulative distribution function (CCDF) shows that SC-FDMA is more power-efficient and has lower PAPR than direct current-biased orthogonal frequency division (DCO-OFDM), achieving approximately 4–5 dB lower PAPR, making UWOC systems more energy-efficient and reducing nonlinearity. The performance of SCF has been tested in various water environments, including pure, clear, coastal, and harbor waters, and SC-FDMA has achieved acceptable coverage distances.