부산대학교 도서관

In this paper, a multi-channel preamble sampling MAC protocol, MCPS, especially designed for wireless sensor networks, is proposed and thoroughly evaluated. MCPS is a low power MAC protocol operating on multichannel using carrier sensing for collision avoidance. Specifically, MCPS exploits all the non-overlapping channels provided by IEEE 802.15.4 physical layer. Basically, MCPS uses one dedicated common control channel to wakeup an intended receiver using a preamble sampling technique. However, data transmission takes place in a dedicated data channel. In fact, MCPS allows each sensor node to dynamically adjust its transmission power when sending strobed preamble or periodically generated data. Indeed, for each possible distance separating a pair of communicating nodes, MCPS adapts the appropriate transmission power and selects the appropriate data channel. By using multiple channels, MCPS allows multiple simultaneous communications reducing hence the end-to-end delay and improving the throughput. MCPS has been implemented using OMNET++ simulator under INET framework, on top of the IEEE 802.15.4 physical layer, which it was improved to support the multi channel communication. Simulation results show that MCPS can greatly improve the network performance especially in terms of throughput and end-to-end delay.