Research Projects

• Efficient Spectrum Allocation and Sharing - developed game theoretic and stochastic modeling based spectrum sharing schemes to enhance spectrum efficiency when users strategically compete for spectrum resources in a dynamic environment, including
  - introducing evolutionary game modeling to study cooperation evolution in spectrum sensing and developing a learning algorithm based on replicator dynamics to approach the optimal collaboration with local throughput observation.                                                                                                                                                 - designing spectrum access coordination for interference management using Markov chain modeling and developing a self-learning algorithm to obtain the optimal access probability.
  - introducing a punishment-based repeated spectrum sharing game to enhance user cooperation with truth-telling mechanisms to motivate users to reveal true private information.
  - designing a multi-winner cognitive spectrum auction scheme with collusion-resistant mechanisms and low-complexity implementations.

• Secure Dynamic Spectrum Access - investigated various malicious attacks, quantified their damage, and designed effective defense strategies, including
  - developing effective channel hopping scheme based on stochastic game modeling for anti-jamming defense with a minimax-Q learning algorithm to maximize the long-term accumulated throughput.
  - deriving optimal power allocation strategies against jamming attacks using Colonel Blotto game modeling.

• Relay Selection and Power Allocation for Cooperative Communications - introduced a Stackelberg (buyer/seller) game over cooperative networks to jointly optimize source and relay nodes’ utilities and developed a distributed implementation based on standard function.

• Resource Allocation for Multimedia Communications - proposed game theoretic approaches to efficiently allocate rate/spectrum resources for multimedia communications, including
  - introducing a noncooperative game for efficient and fair rate allocation and developing a distributed cheat-proof implementation using alternative ascending clock auction.
  - designing a cheat-proof spectrum auction scheme to maximize social welfare for multimedia streaming over cognitive radio networks.