Dual-Hop Underwater Optical Wireless Communication System With Simultaneous Lightwave Information and Power Transfer

Abstract

The most significant challenge of underwater optical wireless communication (UOWC) system is to overcome its limited coverage. To expand the achievable communication range, we investigate the performance of the dual-hop UOWC system with simultaneous lightwave information and power transfer (SLIPT). The time splitting (TS) method is adopted for wireless power transfer in the proposed system, where the information and energy are transmitted in different phases. A suitable transmission strategy is designed for the model without additional power supply, which contains three phases, i.e. information transmission, energy transmission, and forwarding process. The expressions of the average bit error rate (BER) at the target node and the energy harvested by the relay node are derived over underwater attenuation channel. Then, the effects of the TS factor and the distances on the system performance are investigated in two sub-problems, which minimize the average BER while satisfying the energy harvesting and transmitting rate constraints. Numerical results indicate the performance improvement by adopting the relay node with SLIPT.

Reliability of Spectrum-Efficient Mixed Satellite-Underwater Systems

“…where γ n = 2 Rn − 1 is the threshold SNR relating to the target data rate R n at the D n to detect x n , τ = max(τ 1 , τ 2 ), τ 2 = γn an−ηa f γn with a n > ηa f γ n , ν = max(ν 1 , ν 2 ), and ν 2 = γn bn−ηb f γn with b n > ηb f γ n . By substituting (1) and ( 3) in ( 6), the closed-form expression of OP n can be written as in (7) at the top of the next page.…”

“…Further, the UOWC can be linked to the terrestrial communication system via RF links with dual-hop cooperative protocols, which enables the underwater real-time monitoring systems. It has been indicated in [7] that the relaying node is necessary for extending the communication range for UOWC systems. In [5], [8], authors have studied the effectiveness of the amplify-and-forward (AF) relaying protocol with a dual-hop UWOC system.…”

Energy‐efficient UOWC‐RF systems with SLIPT

“…In References 10‐12, multi‐hop UOWC and mixed RF‐UOWC setup was investigated; however harvesting at the relay was not considered. In Reference 13 a dual‐hop SLIPT UOWC system was investigated and BER was minimized by choosing the optimal TS parameter; however fading is not considered. In Reference 15, authors investigate a dual hop full‐duplex (FD) and half‐duplex (HD) setup where they optimize the instantaneous time‐splitting parameter such that the uplink information rate is maximized.…”

“…Furthermore, multi-hop UOWC and mixed RF-UOWC setups are also studied in the literature as they extend the communication coverage and improves overall system performance. [10][11][12][13][14][15] In Reference 10, authors considered a dual-hop UOWC system and determine optimal relay placement to minimize the bit error rate (BER) and extend the results to multihop. However, they consider only path loss and ignore the effect of turbulence and they do not consider SLIPT at the relay.…”

Energy Harvesting in Underwater Acoustic Wireless Sensor Networks: Design, Taxonomy, Applications, Challenges and Future Directions

“…Sensor nodes in UAWSNs have limited battery life and it is infeasible and expensive to replace nodes' batteries [13]. Therefore, harvesting energy for sensor nodes provides a number of advantages [14] [15] [16] [17]. Firstly, it prolongs the network life time by making sensor nodes capable of operating for a long time.…”