Hybrid Underwater Intelligent Communication System

Presently employed underwater communication systems suffer from issues such as low data rates and short communication ranges. In this paper, a novel hybrid underwater intelligent communication system is proposed and modeled to address both issues. The proposed system provides higher data rate, longer communication range and secure data transmission by employing optical fiber, underwater free space optics (UFSO) and free space optics (FSO). An intelligent routing mechanism governed by Tabu search (TS) algorithm is used for optical path selection based on data traffic, data rate and communication length to maintain a desired quality of service (QoS) while ensuring security of data transmission. For, modeling, optical fiber channel, priority aware (PA) scheduling algorithm for packet-switched optical network (PSON) for data transmission is used whereas for the FSO channel modeling, orthogonal frequency division multiplexing (OFDM) and On–Off Keying (OOK) are used.To simulate underwater turbulent conditions for UFSO channel, scintillation model with gamma-gamma distribution (GGD) is applied. A data rate of 10 Gbps with BER of 10 –9 has been achieved for communication ranges of 140 and 200 m for the cases of turbulent and non-turbulent water conditions. In each of the cases, QoS meeting IEEE standards is ensured.