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Resource Allocation

Motivation:

Over the last decade, small portion of unlicensed spectrum has encouraged innovations in wireless networking including wireless LAN, Mesh, blue tooth, and so on. These wireless device has become popular in recent years and has received wide deployments. The small unlicensed portion of spectrum is already overcrowded and tempered the further innovations in wireless technologies. One aparant solution is to allocate more spectrum to encourage such innovations however when we look at the frequency allocation chart in USA, almost all spectrum are already allocated and needs license to operate. There is no more spectrum left to be allocated for future wireless technologies. Sharing of frequency spectrum enables the efficient utilization of frequency in unlicensed bands and such sharing helps incorporate more customers of service providers in licensed bands. However, sharing the spectrum by many users creates the mutual interference to others and hurt overall performance. Next important resource in wireless systems is power, which is related to connectivity to others, energy of the battery and interference to others.

My interests in such multi-user wireless systems is to develop adaptive algorithms
  • to mitigate the interference
  • to optimize the transmitter with QoS constraints
  • to enhance the overall performance
  • to analyze the effect of limited feedback in the implementation of transmitter optimization in distributed manner
Publications:
  • D. C. Popescu, D. B. Rawat, O. Popescu, and M. Saquib. Game Theoretic Approach To Joint Transmitter Adaptation And Power Control in Wireless Systems. IEEE Transactions on Systems, Man, and Cybernetics - Part B, vol. 40, no. 3, pp. 675-682, June 2010.
  • D. B. Rawat and D. C. Popescu. Joint Precoder and Power Adaptation for Cognitive Radios in Interference Systems. In proceedings of the 28th IEEE International Performance Computing and Communications Conference Workshop--IPCCC 2009, presented at The 2nd IEEE International Workshop on Dynamic Spectrum Access and Cognitive Radio Networks, Dec. 14 – 16, 2009, Phoenix, AZ.
  • S. Maharjan, Danda B. Rawat, and Dimitrie C. Popescu. A Simulation Study of Convergence Speed for Distributed Codeword Adaptation Algorithms in CDMA Wireless Systems. Proceedings 2009 IEEE Radio and Wireless Symposium - RWS'09, pp. 425-428, January 2009, San Diego, CA.
  • D. B. Rawat and D. C. Popescu. Joint Codeword and Power Adaptation for CDMA Systems with Multipath and QoS Requirements. Proceedings 2008 IEEE Global Telecommunications Conference - GLOBECOM'08, pp. 4050-4054, December 2008, New Orleans, LA.
  • D. C. Popescu, O. Popescu and D. B. Rawat. Gradient Descent Interference Avoidance with Target SIR Matching. In Proceedings 2006 IEEE Consumer Communications and Networking Conference - CCNC, pp. 200-204, January 2008, Las Vegas, NV.
  • D. C. Popescu, D. B. Rawat, and O. Popescu. Gradient Descent Interference Avoidance for Uplink CDMA Systems with Multipath. Proceedings 41st Annual Asilomar Conference on Signals, Systems, and Computers, pp. 1060 - 1064, November 2007, Pacific Grove, CA.
  • D. C. Popescu, Sirisha Koduri, and D. B. Rawat. Interference Avoidance With Limited Feedback. Proceedings 41st Annual Asilomar Conference on Signals, Systems, and Computers, pp. 1046-1049, November 2007, Pacific Grove, CA.