A Power-Efficient Optical Modem for Reliable, Long-Distance Communication Using GFDM Technology in Underwater and Terrestrial Wireless Systems

This paper presents the design of a GFDM-based optical communication modem using MATLAB SIMULINK to improve the power efficiency, reliability and long distance communication in underwater wireless communication (UWC) systems. Conventional techniques such as orthogonal frequency division multiplexing (OFDM) and single-carrier frequency division multiple access (SC-FDMA) are commonly utilized to enhance data rates, reduce BER, and mitigate the impact of multipath fading. However, these methods come with certain limitations. OFDM, for instance, suffers from a high peak-to-average power ratio (PAPR) and significant out-of-band emissions, whereas SC-FDMA is highly susceptible to inter-symbol interference (ISI) in multipath environments. Generalized frequency division multiplexing (GFDM) provides a better flexibility for reducing the PAPR and improve the robustness against Doppler effects of a critical factor in UWC by using non-orthogonal subcarriers. By using MATLAB SIMULINK, the optical communication modem was developed for long distance signal transmission and reception. This approach enhances channel bandwidth utilization and spatial diversity, making it a more effective solution for underwater wireless communication. As a result, GFDM emerges as a promising alternative to conventional techniques, offering improved modem performance by reducing bit error rate (BER), increasing spectral efficiency, and demonstrating greater resilience to variations in underwater channel conditions.