Running from October 2012 to February 2017, UP-VLC is an ambitious EPSRC-funded £4.6 million Programme Grant which will explore the transformative technology of communications in an imaginative and foresighted way. The vision is built on the unique capabilities of gallium nitride (GaN) optoelectronics to combine optical communications with lighting functions, and especially on the capability to implement new forms of spatial multiplexing, where individual elements in high-density arrays of GaN based light emitting diodes (LEDs) provide independent communications channels, but can combine as displays. We envisage ultra-high data density - potentially Tb/s/mm² - arrays of LEDs driven via CMOS control electronics in novel addressing and encoding schemes and in compact and versatile forms.

  (a)                        (b)                              (c)                                (d)                                (e)

Fig.1 (a) high-fill-factor chequerboard (square grid) GaN LED/CMOS clusters (Strathclyde/Edinburgh), (b) 1Gb/s eye diagram from 84μm-diameter GaN micro-pixel LED (Strathclyde), (c) flexible organic semiconductor grating arrays for hybrid LEDs (Strathclyde/St. Andrews), (d) multiple channel VLC link (Oxford), (e) 124Mb/s real time video VLC transmission demonstration (Edinburgh).

Recently, by integrating CMOS electronics with GaN based micro-LEDs, we have developed CMOS-controlled color-tunable smart displays. The color-tunable LED pixels in these displays have a modulation bandwidth of 100 MHz, thus providing simultaneously a wavelength-agile source for high-speed visible light communications. The programmable dynamic images generated from such a micro-display system are shown below (red ‘Tetris’ and green Firework).

• The next UPVLC project meeting will be hosted by the University of Edinburgh on the 8th and 9th of December.
  
• The UPVLC partnership was "Highly Commended" at The Engineer Magazine's Collaborate to Innovate competition. For further details please see the news section of the website.
• A paper based on collaborative work between the Universities of Cambridge and Strathclyde has been published in the Journal of Lightwave Technology - Wireless Visible Light Communications Employing Feed-Forward Pre-Equalization and PAM-4 Modulation.
• The UPVLC project held an open day event at the Royal Academy of Engineering, London, with Nobel Prize winner Hiroshi Amano as a guest speaker. For more details, see our news section.
• The paper, "μLED-Based Single-Wavelength Bi-directional POF Link With 10 Gb/s Aggregate Data Rate" has recently been published in the IEEE Journal of Lightwave Technology.
• A paper titled "Heterogeneous integration of gallium nitride light-emitting diodes on diamond and silica by transfer printing"was published in the journal Optics Express.
• A MIMO transmission demo, consisting of CMOS-controlled micro-LEDs and a CMOS APD receiver array, was demonstrated at the EPSRC event "Science for a successful nation" at The Royal Society, London on the 2nd of March 2015. For more information see here.
• The UPVLC consortium has been invited to present at The Royal Society meeting on "Communication networks beyond the capacity crunch" to be held on 13th and 14th May at The Royal Society, London.
• The paper "Hybrid GaN LED with capillary-bonded II–VI MQW color-converting membrane for visible light communications" has recently been published in the journal Semiconductor Science and Technology.
• As on the 16th December 2014, 5 of the 12 most downloaded articles from the journal IEEE Photonics Technology Letters were from the UP-VLC consortium.
• Joint work between the Universities of Oxford, St. Andrews, Edinburgh and Strathclyde has been published in a paper titled "Visible Light Communication Using a Blue GaN µLED and Fluorescent Polymer Color Converter" IEEE Photonics Technology Letters.
• The UP-VLC project was featured in an article titled Optical Wireless Communications: The New “Hot Spots”? in the March 2014 edition of Optics and Photonics News, published by OSA.
• Our publication "A 3-Gb/s Single-LED OFDM-based Wireless VLC Link Using a Gallium Nitride μLED" is now published and is available from the IEEE Photonics Technology Letters website.