On-off keying transmitter design for navigation by visible light communication

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

2 Citations (Scopus)


White LEDS revolutionized the field of illumination technology mainly due to the energy saving effects. Besides lighting purposes LEDs can also be used in wireless communication systems when integrated in Visible Light Communication (VLC) systems. Indoor positioning for navigation in large buildings is currently under research to overcome the difficulties associated with the use of GPS in such environments. The motivation for this application is also supported by the possibility of taking advantage of an existing lighting and WiFi infrastructure. In this work it is proposed an indoor navigation system based on the use of VLC technology. The proposed system includes trichromatic white LEDs with the red and blue chips modulated at different frequencies and a pinpin photodetector with selective spectral sensitivity. Optoelectronic features of both optical sources and photodetector device are analyzed. The photodetector device consists two pin structures based on a-SiC:H and a-Si:H with geometrical configuration optimized for the detection of short and large wavelengths in the visible range. Its sensitivity is externally tuned by steady state optical bias. The localization algorithm makes use of the Fourier transform to identify the frequencies present in the photocurrent signal and the wavelength filtering properties of the sensor under front and back optical bias to detect the existing red and blue signals. The viability of the system was demonstrated through the implementation of an automatic algorithm to infer the photodetector cardinal direction. A capacitive optoelectronic model supports the experimental results and explains the device operation.
Original languageEnglish
Title of host publicationOptical Interconnects XVIII
PublisherSpie -- the Int Soc for Optical Engineering
ISBN (Electronic)9781510615618
Publication statusPublished - 2018
EventOptical Interconnects XVIII 2018 - San Francisco, United States
Duration: 29 Jan 201831 Jan 2018


ConferenceOptical Interconnects XVIII 2018
Country/TerritoryUnited States
CitySan Francisco


  • amorphous SiC
  • Indoor positioning
  • On-off modulation.
  • Optoelectronics
  • Spectral sensitivity
  • visible light communication
  • white LEDs


Dive into the research topics of 'On-off keying transmitter design for navigation by visible light communication'. Together they form a unique fingerprint.

Cite this