Speaker: Prof. Xi Zhang
Networking and Information Systems Laboratory,
Department of Electrical and Computer Engineering,
Title: Cognitive Radio Based Multi-Channel MAC Protocols for Wireless Ad Hoc Networks
Abstract: We propose cognitive-radio-based multi-channel medium access control (MAC) protocols, which integrate the spectrum sensing and packet scheduling, for the wireless ad hoc networks. Specifically, our MAC protocols allow the secondary users to identify and use the available frequency spectrum while constraining the level of interference to the primary users. In our scheme, each secondary user is equipped with two transceivers -- one tuned to a dedicated control channel and the other used as a cognitive radio dynamically sensing and using the identified available channels. To obtain the channel status accurately, we propose two collaboratively channel-sensing policies -- the random sensing policy and negotiation-based sensing policy, to help the MAC protocols detect the available channels. We develop the Markov chain model and the M/G^Y/1-based queuing model to validate and evaluate the performance of our proposed multi-channel MAC protocols under the two proposed channel sensing policies in terms of the network aggregate throughput and packets transmission delays.