As the amount of mobile traffic grows dramatically, the high-density Wi-Fi networking that proposed in the next generation WLAN (NGW) has attracted an increasing attention. However, some new challenges on the medium access control (MAC) layer design are emerging, for example, the multichannel hidden terminal (MHT) and the vicious circle problems. To overcome the challenges, a distributed multichannel MAC protocol based on multiple step reliable channel reservation is proposed, called m-RCR. Under the proposed m-RCR protocol, each node pair can reserve multiple transmission opportunities on data channels using only a single half-duplex transceiver, meanwhile, the control channel (CCH) is reserved to rebroadcast the channel reservation information (CRI). An analytical model is developed by extending the two-dimensional Markov process to describe the node behaviors on the CCH, and the usage of data channels is characterized as the M/M/K queueing model, where we consider the packet arrivals as a Poisson process. Furthermore, the throughput of m-RCR protocol is derived, and the performance optimization is also presented. Without loss of generality, some practical implementation methods are discussed. By conducting extensive simulations on NS-2 simulator, our analytical model is validated and the significant improvement of our proposed m-RCR protocol is demonstrated.
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