OFDM based Wireless Systems

• Bring High mobility in OFDM based wireless communication system
• Optimization of equlization techniques for receivers with high mobility
• Analytical analysis for the prediction of equalization performance

Lightfields

• Calibration of multi-dimensional camera arrays to capture lightfields
• Spatio-Temporal sampling of 5-D lightfields.
• 5-D lightfield Analysis as part of a DFG project, ‘FiDALiS’
• Developing means to produce novel visual content with lighfields

Mobile OFDM: Orthogonal Frequency-Division Multiplexing (OFDM) has become a widely used ‘last-mile’ technology in the scope of wireless communication systems. Despite the various benefits of OFDM  (like complexity, spectral shaping and so on); OFDM is sensitive to Doppler shift caused by the relative motion of the transmitter and/or the receiver. The goal of this project is to develop novel schemes that would estimate the channel distortions and equalize the same at the complexity that is relevant for consumer hardware.

5D Lighfields: Analyizing 5D lightfields to develop an optimal sptio-temporal sampling pattern as part of a DFG Project FiDALiS.

• Nominee for the European Google Fellowship 2017
• VDE Absolventenpreis 2016: VDE Saar, the local chapter of VDE, the German Association for Electrical, Electronic & Information Technologies, honors the best Master´s students of Saarland´s universities each year with the VDE Saar award
• Best Paper Award: For the publication, “Bilingual Speech Recognition”  at the International Conference on VLSI and Signal Processing, Bangalore, India, 2012

• WS 2018/2019
  • Telecommunications I (TA)
• SS18
  • Hands-On Wireless (Instructor)
• WS 2017/2018
  • Telecommunications I (TA)
• WS 2016/2017
  • Telecommunications I (TA)
• SS 2016
  • Telecommunications II (TA)
• SS 2015
  • Telecommunications II (TA)
• WS 2014/2015
  • Telecommunications I (Tutor)

• Post-Doc Researcher (Oct’21 – )
• PhD student (May ’15 – Sep’21)
• Scientific Researcher at the Telecommuncations Lab, Uni Saarland (May. ’15 – today)
• Master Student at University of Saarland (October. ’12 – Feb. ’15)
• Research assistant at Max Planck Instistute for Information Technology. Area: Video Segmentation. (Nov. ’12 – Jan. ’15)
• Research assistant at Telecommuncations Lab. Area: Video Rendering (Jul. ’13 –  Sep. 14)
• Student Assistant at the Telecommunications Lab (Oct 2014 – Mar 2015)
• Bachelor Student at Siddaganga Institut of Technology, Tumkur, India.

Running Theses

Finished Theses

Open Theses:

Various topics in the field of Lightfields are open. Feel free to contact me for more information.

• Chelli, Kelvin; Tamboli, Roopak; Herfet, Thorsten: “Deep Learning-based Semantic Analysis of Sparse Light Field Ray Sets”, Accepted at the IEEE 23rd International Workshop on Multimedia Signal Processing (IEEE MMSP), Tampere, Finland 2021
• Herfet, Thorsten; Chelli, Kelvin; Lange, Tobias; Kremer, Robin: “Fristograms: Revealing and Exploiting Light Field Internals“, ArXiv, Juli 2021
• Chelli, Kelvin; Lange, Tobias; Herfet, Thorsten: A Flexible 5D Light Field Capturing Array, in the NEM summit 2020. 
• Trottnow, J.; Spielmann, S.; Herfet, Th.; Aenchbacher, W.; Grogan, M.; Alain, M.; Smolic, A.; Solony, M.; Smrz, P.; Zemcik, P.; Canham, T.; Lange, T.; Chelli, K.: “The Potential of Light Fields in Media Productions”, Accepted to SIGGRAPH Asia, Brisbane, Australia, November 2019.
• Chelli, Kelvin; Theodory, Ramzi, Herfet, Thorsten: “Compressed Sensing Channel Estimation for LTE-V”, in the 2nd International Conference on 5G for Uniquitous Connectivity (5Gu), Nanjing, China, 2018.
• Chelli, Kelvin; Herfet, Thorsten: “Estimating Doubly-Selective Channels in DVB-T2”, in the 13th IEEE International Symposium on Broadband Multimedia Systems and Broadcasting 2018, Valencia, Spain, 2018.
• Sirsi, Praharsha; Chelli, Kelvin;  Herfet, Thorsten: “Tap Coefficient Based Cognitive Framework for Estimating a Dynamic Channel”, accepted to the 2nd International Conference on Circuits, Controls and Communications, Bangalore, December 2017
• Chelli, Kelvin; Sirsi, Praharsha;  Herfet, Thorsten: “Cognitive Framework for the Estimation of Doubly Selective Channels” in the 86th IEEE Vehicular Technology Conference, Toronto, Canada, September 2017
• Chelli, Kelvin; Sirsi, Praharsha;  Herfet, Thorsten: “Complexity Reduction for Consumer Device Compressed Sensing Channel Estimation” in the 7th IEEE International Conference of Consumer Electronics, Berlin, Germany, September 2017
• Chelli, Kelvin; Sirsi, Praharsha;  Herfet, Thorsten: “Sparse Doubly-Selective Channels: Estimating Path Parameters Unambiguously” in the 26th European Conference on Networks and Communications, Oulu, Finland, June 2017
• Chelli, Kelvin; Herfet, Thorsten: “Time-Domain Pilots in DVB-T2”, in the 12th IEEE International Symposium on Broadband Multimedia Systems and Broadcasting 2017, Cagliari, Italy, June 2017.
• Chelli, Kelvin; Herfet, Thorsten: “Doppler Shift Compensation in Vehicular Communication Systems”, IEEE International Conference on Computer and Communications (ICCC), Chengdu, October 2016
• “Doppler Shift Compensation in Vehicular Communication Systems”, Master Thesis at Saarland University, Saarbrücken Germany, 2015
• Santoshkumar; C.Kelvin; C.Chavhan; “Development of Wireless Sensor Node to monitor poultry farm”, Communications in Computer and Information Science, Bangalore, India., 2012.
• Pranesh; Chelli et.al, “Bilingual Speech Recognition System” International Conference on VLSI and Signal Processing, Bangalore, India, 2012