Cooperative communications in wireless networks : novel approaches in the mac layer

In this thesis, different novel approaches for the cooperative communication problem in the medium access control (MAC) layer are proposed. The novelty of this thesis is two-fold. We first investigate the problem of cooperative communication in a special type of wireless networks, namely ultra wide-band (UWB) networks, for the first time in the literature. The importance of cooperation schemes in UWB is the promising potentials of UWB for developing a robust and high performance wireless infrastructure. Secondly, we design a novel Markov decision process (MDP) framework for the cooperative retransmission problem in the wireless networks. This MDP model is proven to be simple, yet very efficient approach for distributed optimization and decision making in the cooperation problem. We show that the proposed MDP-based cooperation schemes and their extensions to reinforcement learning (RL) and partially observable MDP (POMDP) models are all able to significantly improve the throughput and energy consumption in a wireless network.

Author dc:creator

• GHASEM NADDAF ZADEH SHIRAZI

• Cooperative communication; Ultra Wideband (UWB) MAC; Cooperative retransmission; Markov Decision Process (MDP); Reinforcement Learning; Optimization