DCR-MAC: a data channel recommending MAC for multi-channel WLANs toward the higher throughput performance

Recently, many MAC protocols have been proposed for effective communication in the single transceiver multi-channel environment. In these MAC protocols, however, the multi-channel hidden terminal problem degrades the throughput of the communication systems. In order to mitigate the effects of the multi-channel hidden terminals, two MAC protocols have been proposed: cooperative asynchronous multi-channel MAC (CAM-MAC), where neighbouring terminals inform a sender of its bad channel selection and virtual topology MAC (VT-MAC), where redundant channel usage information is reduced by considering the network topology. However, these MAC protocols mainly focus on avoiding bad channel selections by the sender, and not on increasing good channel selections (concurrent transmissions). Therefore, in this paper, to further improve throughput performance by concurrent transmissions, we propose new multi-channel MAC protocols in which neighbour terminals of a sender recommend a better transmission channel prior to the data transmission. The performance evaluations verify that the proposed MAC protocol effectively improves the throughput performance when compared to existing MAC protocols, especially when the channel negotiation process induces the larger overhead at the short data transmission.