在過去的十幾年中，許多的多頻道媒介存取控制協定已被研究以久。隨著硬體成本與設備能力的考量，許多研究者提出了只使用單一無線收發器的媒介存取控制協定，而即使在網路中，使用多個收發器會比使用單一收發器有可能有更高的網路流量。在本論文中，我們提出了一種新的合作式多通道多頻道媒介存取控制協定，此媒介存取控制協定採用了合作式的概念，並將此概念整合進使用單一無線收發器的媒介存取控制協定中，以滿足有多個無線收發器的需求。我們所提出的協定是基於著名的多通道協定，時槽種子頻道跳躍(Slotted Seeded Channel Hopping, SSCH)協定所設計，而在我們所提出的協定中，每個設備也只需要單一無線收發器。因此在IEEE 802.11多頻道多點跳躍的無線網路環境中，我們設計了一個中繼節點選擇方法讓一個中間節點與一個中繼節點成為一個虛擬節點。我們也設計了頻道分配機制，讓此虛擬節點能夠同時發送和接收資料在不同的頻道上，以提高網路效能。模擬結果証明，無論在網路容量與平均封包延遲上，我們的方法明顯優於原本的SSCH協定。

Numerous multi-channel MAC protocols have been studied in the past decade. With the
concerns of hardware cost and device capability, many researchers have proposed protocols
that utilize only single transceiver even though the network with multiple transceivers can
potentially have higher capacity than a network with a single transceiver. In this paper, we
introduce a novel cooperative multi-channel MAC protocol that incorporates the notion
of cooperative communication into the multi-channel MAC protocols which utilize single
transceiver to satisfy multiple transceivers requirement. The proposed protocol is designed
based on the well-known multi-channel protocol SSCH, and requires only one transceiver
per device. Hence, under the IEEE 802.11 multi-channel multi-hop wireless network
environment, we design a relay node selection approach to select a relay node and let an
intermediate node become a virtual node with the relay node. We also design a channel
assignment mechanism to let the virtual node transmit and receive data simultaneously on
different channels for improving the network performance. Simulation results show that
our protocol significantly outperforms the original SSCH in terms of network capacity
and average packet delay.

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