| Summary: | 碩士 === 國立雲林科技大學 === 通訊工程研究所碩士班 === 99 === In recent years, many Medium Access Control (MAC) protocols were proposed to save power, such as Berkeley-MAC (B-MAC), Sift and Zebra MAC (Z-MAC), etc. B-MAC performs low power consumption communication by means of preamble sequence and low-power listening. Sift-MAC arranges the order of delivery for all nodes using random back-off mechanism, when they sense the same event. The node which has the shortest back-off time will deliver the data first. Thus the node reduces collision probability and energy consumption. Z-MAC is a kind of hybrid MAC protocol, which combines Carrier Sense Multiple Access (CSMA) and Time Division Multiple Access (TDMA). Z-MAC uses TDMA in the case of high contention level to avoid collision and interference, and uses CSMA in the case of low contention level to improve utilization and reduce delay. In this thesis, we present four new MAC protocols, such as N-MAC, BZ-MAC, BN-MAC and BT-MAC. These four MAC are all hybrid MAC protocol because they combine B-MAC, Sift-MAC, and Z-MAC. The first one, N-MAC, is the modification of Z-MAC. An owner of the node can transmit data in TDMA-MAC, on the other hand a nonowner of a node transmits in Sift-MAC. The second one is BZ-MAC. If nodes are less than six, nodes can be transmitted in B-MAC. When nodes are more than seven, they can be transmitted in Z-MAC. The third one is BN-MAC protocol. When nodes are less than six, we use B-MAC to transmit. When nodes are more than seven, then we use N-MAC to transmit. The last one is BT-MAC protocol. When nodes are less than six, we use B-MAC protocol to transmit. When nodes are more than seven, then we use TDMA-MAC to transmit. According to the analysis revealing, the average throughput and the average utilization of the four hybrid MAC protocols are higher than B-MAC, Sift and Z-MAC. Analysis result shows that the performance of BT-MAC in terms of throughput, collision probability and utilization is the best.
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