PixNet: Interference-Free Wireless Links Using LCD-Camera Pairs
overview
Given the abundance of cameras and LCDs in today's environ-
ment, there exists an untapped opportunity for using these de-
vices for communication. Specically, cameras can tune to nearby
LCDs and use them for network access. The key feature of these
LCD-camera links is that they are highly directional and hence
enable a form of interference-free wireless communication. This
makes them an attractive technology for dense, high contention
scenarios. The main challenge however, to enable such LCD-
camera links is to maximize coverage, that is to deliver multiple
Mb/s over multi-meter distances, independent of the view angle.
To do so, these links need to address unique types of channel
distortions, such as perspective distortion and blur.
This project explores this novel communication medium and
presents PixNet, a system for transmitting information over LCD-
camera links. PixNet generalizes the popular OFDM transmis-
sion algorithms to address the unique characteristics of the LCD-
camera link which include perspective distortion, blur, and sen-
sitivity to ambient light. We have built a prototype of PixNet
using o-the-shelf LCDs and cameras. An extensive evaluation
shows that a single PixNet link delivers data rates of up to 12
Mb/s at a distance of 10 meters, and works with view angles as
wide as 120 degrees.
papers
PixNet: Interference-Free Wireless Links Using LCD-Camera Pairs,
Samuel Perli, Nabeel Ahmad, and Dina Ktabi,
ACM MOBICOM, 2010.PDF
people
Samuel Perli
Massachusetts Institute of Technology
Nabeel Ahmed
Massachusetts Institute of Technology
Dina Katabi
Massachusetts Institute of Technology