Optimal scheduling and power allocation in cooperate-to-join cognitive radio networks

Karaca M., Khalil K., Ekici E., Ercetin O.

IEEE/ACM Transactions on Networking, vol.21, no.6, pp.1708-1721, 2013 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 21 Issue: 6
  • Publication Date: 2013
  • Doi Number: 10.1109/tnet.2012.2230187
  • Journal Name: IEEE/ACM Transactions on Networking
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1708-1721
  • Keywords: Cognitive radios, Lyapunov optimization, opportunistic scheduling, resource allocation, spectrum leasing
  • TED University Affiliated: No


In this paper, optimal resource allocation policies are characterized for wireless cognitive networks under the spectrum leasing model. We propose cooperative schemes in which secondary users share the time-slot with primary users in return for cooperation. Cooperation is feasible only if the primary system's performance is improved over the non-cooperative case. First, we investigate a scheduling problem where secondary users are interested in immediate rewards. Here, we consider both infinite and finite backlog cases. Then, we formulate another problem where the secondary users are guaranteed a portion of the primary utility, on a long-term basis, in return for cooperation. Finally, we present a power allocation problem where the goal is to maximize the expected net benefit defined as utility minus cost of energy. Our proposed scheduling policies are shown to outperform non-cooperative scheduling policies, in terms of expected utility and net benefit, for a given set of feasible constraints. Based on Lyapunov optimization techniques, we show that our schemes are arbitrarily close to the optimal performance at the price of reduced convergence rate. © 2012 IEEE.