Abstract: IEEE802.11 multi-rate mechanism OAR can better utilize wireless channel conditions, but it does not work well in the congestion network environment. This paper improves the OAR algorithm, whch increases the probability to obtain the channel of the congestion node by adjusting the initial competition window size. So they can transmit the congestion pakets as soon as possible, thus congestion is relieved. Simulation results indicate the ratio of packet delivering of OAR is improved.

Key words: IEEE802.11 multi-rate mechanism, OAR algorithm, congestion

摘要： IEEE802.11的速率选择算法OAR能有效利用信道条件，但不适合拥塞的网络环境。该文改进OAR算法，通过调整拥塞节点的初始竞争窗口值来增加其获得信道的概率，使其在拥塞时能尽快将分组转发出去，从而缓解了拥塞。仿真结果表明，改进后的OAR在网络负荷大时能有效地提高分组投递率。

关键词: IEEE802.11多速率机制, OAR算法, 拥塞

CLC Number: 

• TP393