Recent Trends in Electromagnetics and Optics
Organized by the Electronics and Telecommunication Engineering Department | IIEST, Shibpur
DST-SERB sponsored Workshop
Prof. Abhirup Das Barman
University of Calcutta
Topic of Lecture:
INDOOR OPTICAL WIRELESS COMMUNICATION USING WHITE LEDs AND ITS CHALLENGES
Abstract of Lecture:
New High-Data-Rate Multimedia Services & Aplications are evolving Day-by-day to meet the Exponentially Increasing Demand for Wireless Capacity of Fifth-Generation (5G) & beyond. The Existing Radio Frequency (RF) Communication Spectrum is Insufficient to meet the Demands of Future High-Data-Rate 5G Services. Optical Wireless Communication (OWC), which uses an Ultra-wide Range of Unregulated Spectrum, has emerged as a Promising Solution to overcome the RF Spectrum Crisis.
Improving Bit-rate by means of White LEDs for Wireless Indoor Data Communication is a Challenging Problem. White LED can provide Energy Efficient Illumination in the Rooms as well as can be used for Data Modulations. IEEE 802.15.7 New Standard has been set up to achieve this Goal which speaks in favour of Colour Shift Keying (CSK) Modulation. Conventional On-off Keying (OOK), CSK & OFDM Modulation of Light using White LEDs are the Topics of Interest. An Advantage of CSK is that the Power Envelope of the Transmitted Signal is held Constant by combining the Light Intensities of the Red (R), Green (G) & Blue (B) Monochromatic Lights of a White LED.
Decoding Techniques for CSK Modulation is a Challenging Task. Optical OFDM based Technique on the otherhand, finds Promising Solutions which are currently being investigated. But maintaining High-Data-Rate under Dimming Control of Light is a Challenge to be solved. We have designed Multi-level CSK for High Bit Rate Transmission & analysed its Performance in the Laboratory. In this work, Voroni Segmentation Technique is employed for Coding & Decoding of CSK Constellation & System Performance is analyzed. Simple Linear Equalization Method can be used to mitigate Non-linearities in LEDs which is found Suitable to reduce Inter Symbol Interference (ISI), and provide Improved Symbol Error Rate & SNR Performances of the Received Signal.
A Bit About Prof. Das Barman
Abhirup Das Barman received the Bachelors’ Degree (B.Tech) in Electronics & Communication Engineering (ECE) from the Institute of Radio Physics & Electronics (IRPE), Calcutta Univ. in 1991 and thereafter Master Degree (M.Tech.) in Electrical Engineering (EE) from IIT Kanpur and Ph.D. from IRPE, Calcutta University. In between, he worked Few Years in Indian Broadcasting Engineering Service (IBES), Government of India in the Areas of Digital Terrestrial Transmitter (DTT), Commissioning & Maintenance of Satellite Earth Stations, Digital Studio etc. Later, he joined as a Faculty in the Dept. of Radio Physics & Electronics, Univ. of Calcutta. Since 2014, he is a Professor in this Department. In 2007 & 2009, he worked as a Visiting Researcher at the CNIT Photonic Networks National Laboratory, Pisa, Italy. In 2010-11, he worked as a Researcher in Aalborg University, Denmark in the Dept. of Electronic Systems. In 2015, he worked as a Visiting Researcher at Limerick University, Ireland, Dept. of Computer Science and Engineering under Erasmus Mundus European Union Scholarship. He has more than 80 Publications in International Repute Journal & Conference. He was a Principal Investigator of Joint Indo Italy Bilateral Project of DST. He completed High-valued Projects of DeiTY in the Area of Cognitive Radio Communication. Currently he is acting as a Co-PI of S. T. Phased Array Radar Project funded by SERB. His Present Active Area of Research is Microwave Photonics & Signal Processing in Communications.