2 Gbps/3 m air–underwater optical wireless communication based on a single-layer quantum dot blue micro-LED
Zixian Wei, Li Zhang, Lei Wang, Chien-Ju Chen, Alberto Pepe, Xin Liu, Kai-Chia Chen, Meng‐Chyi Wu, Yuhan Dong, Lai Wang, Yi Luo, H. Y. Fu
Abstract
Blue/green light-emitting diodes (LEDs) show great potential in medium/short distance underwater optical wireless communication (UOWC) while suffering limited bandwidth caused by a long radiative recombination carrier lifetime and large resistance–capacitance (RC) constant. We designed, fabricated, and packaged a 75-µm single-layer quantum dot (QD) blue micro-LED with a record high modulation bandwidth up to 1.03 GHz. The single-layer structure of QD reduces the carrier lifetime and RC delay. A data rate of 2 Gbps over a 3-m air–underwater channel using a non-return-to-zero on–off-keying modulation format with a low bit-error rate of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mn>2</mml:mn> <mml:mo>.</mml:mo> <mml:mn>03</mml:mn> <mml:mo>×</mml:mo> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:msup> <mml:mn>10</mml:mn> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mo>−</mml:mo> <mml:mn>3</mml:mn> </mml:mrow> </mml:msup> </mml:mrow> </mml:math> was achieved below the forward error correction limit, which is the highest data rate of micro-LED-based UOWC systems, to the best of our knowledge.