Analysis on Cognitive Wireless Network Mac Protocol Access Mode Based on Ns2

Aiming at the same frequency interference, in the channel increased frequency recognition function before the consultation and put forward based on the frequency of perception multiple channel CC-MMAC agreement, simulation verification protocol can effectively reduce the co-channel interference. Channel quality changes with time by the effects of the decline and dispersion, thus cause a certain impact to the network performance, therefore the Gauss channel and the fading channel MAC protocol model are established; In study of rate based on adaptive control, performance analysis take to the rate adaptation leave C protocol, put forward based on the chance rate adaptive OAR DCA channel protocol can improve the network throughput effectively. In the study of multipath routing protocol based on AODV introduce next hop routing layer thought to the MAC layer and proposed the establishment of a plurality of next hop MNH a MMAC protocol; On improving AODV routing protocol establish non-connection limit NDL AODV routing protocol and then make simulation analysis and comparison to the NDL AODV+MNHMMAC agreement with the original AODV+MMAC protocol, it can be in the frequency resource more nervous conditions improve the performance of the network.