ECE seminar series: Camera Based Communication Using Visual MIMO

Wednesday, November 6, 2013 ( 3:00 pm to 4:00 pm )

Location: Babbio Center, Room 319

Prof. Yingying Chen (

Camera Based Communication Using Visual MIMO



The recent years have seen a surge in interest in optical wireless systems through a concept called Visible Light Communication (VLC), where light emitting diodes (LED) are used to transmit information to photoreceptors. Arrays of light emitting elements in the form of high resolution displays equipped with LEDs or LCDs, and light-sensing elements in the form of photodetectors or pixels in camera are pervasive in today's computing devices. The ubiquitous use of LEDs, LCDs and cameras motivates to build novel VLC applications using a concept we call 'visual MIMO'. In visual MIMO, light emitting arrays (LEA) are used to transmit information which are sensed and decoded by the photoreceptor arrays (pixels) in a camera receiver. Examples of LEAs include LED arrays, LCD pixels, and even micromirror arrays (combined with a light source) in projection devices. The paradigm shift in this design is the use of array structure to facilitate the use of image analysis and computer vision techniques to aid in the demodulation of information, contrary to the direct processing of electrical signals at the receiver as in RF MIMO. In visual MIMO, array receivers together with LEAs allow multiple parallel channels as in RF MIMO to achieve throughput gains, but these gains depend on the perspective - orientation and distance - between the transmitter and receiver, and not multipath fading as in RF-MIMO. In this talk, i will discuss how perspective of the camera governs the data-rates in a camera channel and also the prototypes we have built for visual MIMO applications.



Ashwin Ashok is working towards his doctoral degree at WINLAB in the Dept. of ECE at Rutgers University, under the guidance of Profs. Marco Gruteser and Narayan Mandayam, and collaborates with Prof. Kristin Dana on the visual MIMO project. His research interest lies in building novel light based communication systems, applied to vehicular communication, pervasive mobile communication and wearable systems. During his internship at QualComm, NJ in summer 2013 he worked on a novel indoor positioning system using ceiling lamps and a smartphone camera. In his free time he likes tinkering with Arduino and plays badminton and cricket. He is currently on the academic job market.