Multifunctional difluoroboron β-diketonate-based luminescent receiver for a high-speed underwater wireless optical communication system

The last decade has witnessed considerable progress in underwater wireless optical communication in complex environments, particularly in exploring the deep sea. However, it is difficult to maintain a precise point-to-point reception at all times due to severe turbulence in actual situations. To facilitate efficient data transmission, the color-conversion technique offers a paradigm shift in large-area and omnidirectional light detection, which can effectively alleviate the etendue limit by decoupling the field of view and optical gain. In this work, we investigated a series of difluoroboron beta-diketonate fluorophores by measuring their photophysical properties and optical wireless communication performances. The emission colors were tuned from blue to green, and >0.5 Gb/s data transmission was achieved with individual color channel in free space by implementing an orthogonal frequency-division multiplexing (OFDM) modulation scheme. In the underwater experiment, the fluorophore with the highest transmission speed was fabricated into a 4x4 cm(2) luminescent concentrator, with the concentrated emission from the edges coupled with an optical fiber array, for large-area photodetection and optical beam tracking. The net data rates of 130 Mb/s and 217 Mb/s were achieved based on nonreturn-to-zero on-off keying and OFDM modulation schemes, respectively. Further, the same device was used to demonstrate the linear light beam tracking function with high accuracy, which is beneficial for sustaining a reliable and stable connection in a dynamic, turbulent underwater environment. (c) 2023 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Automated summary

Considerable progress has been made in underwater wireless optical communication in complex environments, especially in exploring the deep sea. The color-conversion technique offers a paradigm shift in large-area and omnidirectional light detection, improving data transmission efficiency. This study investigates difluoroboron beta-diketonate fluorophores for their photophysical properties and optical wireless communication performances.