Conventional line-of-sight underwater wireless optical communication(UWOC)links suffer from huge signal fading in the presence of oceanic turbulence due to misalignment,which is caused by variations in the refractive ...Conventional line-of-sight underwater wireless optical communication(UWOC)links suffer from huge signal fading in the presence of oceanic turbulence due to misalignment,which is caused by variations in the refractive index in the water.Non-line-of-sight(NLOS)communication,a novel underwater communication configuration,which has eased the requirements on the alignment,is supposed to enhance the robustness of the UWOC links in the presence of such turbulence.This Letter experimentally and statistically studies the impact of turbulence that arises from temperature gradient variations and the presence of different air bubble populations on NLOS optical channels.The results suggest that temperature gradient-induced turbulence causes negligible signal fading to the NLOS link.Furthermore,the presence of air bubbles with different populations and sizes can enhance the received signal power by seizing the scattering phenomena from an ultraviolet 377 nm laser diode.展开更多
This tutorial focuses on devices and technologies that are part of laser-based visible light communication(VLC)systems. Laser-based VLC systems have advantages over their light-emitting-diode-based counterparts, inclu...This tutorial focuses on devices and technologies that are part of laser-based visible light communication(VLC)systems. Laser-based VLC systems have advantages over their light-emitting-diode-based counterparts, including having high transmission speed and long transmission distance. We summarize terminologies related to laser-based solid-state lighting and VLC, and further review the advances in device design and performance.The high-speed modulation characteristics of laser diodes and superluminescent diodes and the on-chip integration of optoelectronic components in the visible color regime, such as the high-speed integrated photodetector,are introduced. The modulation technology for laser-based white light communication systems and the challenges for future development are then discussed.展开更多
基金supported by the King Abdullah University of Science and Technology(KAUST)(baseline funding,BAS/1/1614-01-01,KAUST funding KCR/1/2081-01-01,and GEN/1/6607-01-01)T.K.N.and B.S.O.gratefully acknowledge funding from King Abdulaziz City for Science and Technology(KACST)Grant KACST TIC R2-FP-008
文摘Conventional line-of-sight underwater wireless optical communication(UWOC)links suffer from huge signal fading in the presence of oceanic turbulence due to misalignment,which is caused by variations in the refractive index in the water.Non-line-of-sight(NLOS)communication,a novel underwater communication configuration,which has eased the requirements on the alignment,is supposed to enhance the robustness of the UWOC links in the presence of such turbulence.This Letter experimentally and statistically studies the impact of turbulence that arises from temperature gradient variations and the presence of different air bubble populations on NLOS optical channels.The results suggest that temperature gradient-induced turbulence causes negligible signal fading to the NLOS link.Furthermore,the presence of air bubbles with different populations and sizes can enhance the received signal power by seizing the scattering phenomena from an ultraviolet 377 nm laser diode.
文摘This tutorial focuses on devices and technologies that are part of laser-based visible light communication(VLC)systems. Laser-based VLC systems have advantages over their light-emitting-diode-based counterparts, including having high transmission speed and long transmission distance. We summarize terminologies related to laser-based solid-state lighting and VLC, and further review the advances in device design and performance.The high-speed modulation characteristics of laser diodes and superluminescent diodes and the on-chip integration of optoelectronic components in the visible color regime, such as the high-speed integrated photodetector,are introduced. The modulation technology for laser-based white light communication systems and the challenges for future development are then discussed.