High Speed Visible Light Communication Using Blue GaN Laser Diodes

Watson, S. et al. (2016) High Speed Visible Light Communication Using Blue GaN Laser Diodes. In: Advanced Free-Space Optical Communication Techniques and Applications II, Edinburgh, UK, 26-29 Sept 2016, 99910A. (doi: 10.1117/12.2245495)

133213.pdf - Published Version



GaN-based laser diodes have been developed over the last 20 years making them desirable for many security and defence applications, in particular, free space laser communications. Unlike their LED counterparts, laser diodes are not limited by their carrier lifetime which makes them attractive for high speed communication, whether in free space, through fiber or underwater. Gigabit data transmission can be achieved in free space by modulating the visible light from the laser with a pseudo-random bit sequence (PRBS), with recent results approaching 5 Gbit/s error free data transmission. By exploiting the low-loss in the blue part of the spectrum through water, data transmission experiments have also been conducted to show rates of 2.5 Gbit/s underwater. Different water types have been tested to monitor the effect of scattering and to see how this affects the overall transmission rate and distance. This is of great interest for communication with unmanned underwater vehicles (UUV) as the current method using acoustics is much slower and vulnerable to interception. These types of laser diodes can typically reach 50-100 mW of power which increases the length at which the data can be transmitted. This distance could be further improved by making use of high power laser arrays. Highly uniform GaN substrates with low defectivity allow individually addressable laser bars to be fabricated. This could ultimately increase optical power levels to 4 W for a 20-emitter array. Overall, the development of GaN laser diodes will play an important part in free space optical communications and will be vital in the advancement of security and defence applications.

Item Type:Conference Proceedings
Glasgow Author(s) Enlighten ID:Watson, Dr Scott and Kelly, Professor Anthony and Giuliano, Mr Giovanni and VIOLA, SHAUN
Authors: Watson, S., Viola, S., Giuliano, G., Najda, S.P., Perlin, P., Suski, T., Marona, L., Leszczyński, M., Wisniewski, P., Czernecki, R., Targowski, G., Watson, M. A., White, H., Rowe, D., Laycock, L., and Kelly, A.E.
College/School:College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
Copyright Holders:Copyright © 2016 SPIE
Publisher Policy:Reproduced in accordance with the copyright policy of the publisher

University Staff: Request a correction | Enlighten Editors: Update this record