VLCR: Detecting Battery-free Users with Visible Lights
Youling Zhou, Yongqin Yang
Available Online July 2015.
- https://doi.org/10.2991/icismme-15.2015.25How to use a DOI?
- Cognitive Radio; visible light communication; RFID.
- This paper presents the design and implementation of VLCR (visible light cognitive radio), a cognitive radio system where the base station can detect and communicate with users in a battery-free manner on the visible light band. Contrary to previous systems, VLCR works at visible light frequencies, which makes detecting users much harder because of the broad bandwidth and the low power constraint it incurs. We solve the power constraint problem by using a retro-reflector that can effectively focus optical energy, returning all the energy back to the base station passively, and an liquid-crystal display (LCD) that can modulate visible light signals efficiently. We have prototyped VLCR and showed that VLCR saves 2-3 orders of magnitude more power than previous cognitive radio systems, and supports concurrent operations among multiple users in the office environment.
- Open Access
- This is an open access article distributed under the CC BY-NC license.
Cite this article
TY - CONF AU - Youling Zhou AU - Yongqin Yang PY - 2015/07 DA - 2015/07 TI - VLCR: Detecting Battery-free Users with Visible Lights BT - First International Conference on Information Sciences, Machinery, Materials and Energy PB - Atlantis Press SP - 122 EP - 126 SN - 1951-6851 UR - https://doi.org/10.2991/icismme-15.2015.25 DO - https://doi.org/10.2991/icismme-15.2015.25 ID - Zhou2015/07 ER -