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Recently, many MAC protocols have been proposed for making effective communications under the single transceiver and multi-channel environment. In those MAC protocols, however, occurrence of multi-channel hidden terminals problem degrades throughput performance of communication systems. Then, in order to mitigate bad effects of the multi-channel hidden terminals, both MAC protocols that are CAM-MAC and VT-MAC are proposed for informing the bad channel selection to sender by its neighboring terminals, and for reducing redundant channel usage information on the basis of considering network topology, respectively. But, these MAC protocols are mainly focused for avoiding bad channel selections by sender, not the increasing good channel selections (concurrent transmissions). Therefore, in this paper, for further improving throughput performance by concurrent transmissions, we propose new multi-channel MAC protocols in which neighbor terminals of sender recommend better transmission channel, prior to the DATA transmission. The performance evaluations clarify that the proposed MAC protocol effective improves the throughput performance than the existing MAC protocols. |
