In this chapter, the DCR protocol adopts an approach that reservation slot of RCH and data packet transmission slot of TCH are the same. Each node utilizes reservation slot and contention micro-slot random backoff mechanism to make a RTS/CTS channel reservation with a half-duplex transceiver and carries out conflict-free data packet sending and confirmation on TCH, thus realizing the parallel channel reservation and data packet transmission of the best traffic balance and avoiding the channel resources waste. At the same time, this protocol allows the exposed terminal sender and the receiver and sender of hidden terminal to carry on simultaneous transmission and reception, which improves the opportunities for parallel data packet sent and minimizes the reservation packet collision interval, thus greatly improving the channel access success rate and efficiency. This protocol does not require channel state table, does not need to change the RTS, CTS packet format, does not need to set and update the NAV for the transceiver backoff, and does not need extra channel and hardware devices, which greatly reduces the overhead, cost and complexity, and provides a good compatibility. Besides, the multiple-access performance can reach a maximum by optimizing the data rate allocation of RCH and TCH. The simulation results show that the DCR protocol in terms of network throughput and average packet delay under the condition of the same total data rate are much better than IEEE 802.11 DCF protocol.
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