Cognitive Radio Oriented Wireless Networks. 12th International Conference, CROWNCOM 2017, Lisbon, Portugal, September 20-21, 2017, Proceedings

Research Article

Impact of Uncertainty About a User to be Active on OFDM Transmission Strategies

  • @INPROCEEDINGS{10.1007/978-3-319-76207-4_18,
        author={Andrey Garnaev and Wade Trappe and Ratnesh Kumbhkar and Narayan Mandayam},
        title={Impact of Uncertainty About a User to be Active on OFDM Transmission Strategies},
        proceedings={Cognitive Radio Oriented Wireless Networks. 12th International Conference, CROWNCOM 2017, Lisbon, Portugal, September 20-21, 2017, Proceedings},
        proceedings_a={CROWNCOM},
        year={2018},
        month={3},
        keywords={OFDM Nash equilibrium NC-OFDM Multicarrier modulation},
        doi={10.1007/978-3-319-76207-4_18}
    }
    
  • Andrey Garnaev
    Wade Trappe
    Ratnesh Kumbhkar
    Narayan Mandayam
    Year: 2018
    Impact of Uncertainty About a User to be Active on OFDM Transmission Strategies
    CROWNCOM
    Springer
    DOI: 10.1007/978-3-319-76207-4_18
Andrey Garnaev1,*, Wade Trappe1,*, Ratnesh Kumbhkar1,*, Narayan Mandayam1,*
  • 1: Rutgers University
*Contact email: garnaev@yahoo.com, trappe@winlab.rutgers.edu, ratnesh@winlab.rutgers.edu, narayan@winlab.rutgers.edu

Abstract

In this paper we investigate the impact that incomplete knowledge regarding user activity can have on the equilibrium transmission strategy for an OFDM-based communication system. The problem is formulated as a two user non-zero sum game for independent fading channel gains, where the equilibrium strategies are derived in closed form. This allows one to show that a decrease in uncertainty about the user activity could reduce the number of subcarriers jointly used by the users. For the boundary case (with complete information, which reflects a classical water-filling game) the equilibrium strategies are given explicitly. The necessary and sufficient conditions, when channels sharing strategies are optimal, is established as well as the set of shared subcarriers is identified. The stability of the upper bound of the size of this set with respect to power budgets is derived.