EDCA Network under CFB Mode

In this paper, we first study the characteristic of the IEEE 802.11 DCF, the IEEE 802.11e EDCA and the CFB mechanism. And presents Markov chain model for the EDCA and CFB mechanism, analyse the system delay, throughput, packet loss rate. Seconed, in the NS-2 network simulation platform, we simulate the three mechanisms under the complex network topology. Moreover we simulate the system delay, throughput, packet loss rate to verify the correctness of the theory, and prove that the QoS characteristic of EDCA compared to the traditional DCF and CFB can improve the channel utilization. Third, we use NS-2 simulate the impact of the different system parameters on network performance, especially the TXOPlimit (Transmission Opportunity). Form the simulate relust we point out the effect of TXOP. Finally, we present a network topology to achieve the real network which has a large number of nodes and each station can send frame randomly. Then study the new network topology performance and the effect of the CFB mechanism.