Effect Of Hidden Nodes On Performance Of IEEE 802.11 WLAN

In the recent years, with the rapid progress of wireless communication technology and local network technology grow rapidly. With the IEEE 802.11 standards continuous improvement and development, the Wireless Local Networks (WLANs) have achieved increasingly wide applications. Wireless Local Area Network technology is widely used in all areas of society and becomes more and more popular because of its convenience, high transmission rate, mobility and extendibility. At the same time, people have focused more attention on the performance of the Wireless Local Networks under any different environments.IEEE 802.11 wireless local area networks use the shared radio channel for information transmission, so there are some different problems with the wired networks, its physical layer and MAC layer is considered to be unreliable. Such as: near-far effect, hidden terminal problem, capture effect and so on. These issues affect the wireless LAN can not be ignored.In order to improve the accuracy of analysis, we consider the effect of the presence of hidden nodes on Wireless LANs, with the current widespread use of two-dimensional Markov model to analyze the performance of the access mechanism of IEEE 802.11 WLAN.On the base of the present analysis which has been based on literature, we propose a new and effective algorithm to calculate the effect of the presence of hidden nodes on Wireless LANs。With the actual situation of network, using this algorithm and considering the effect of non-ideal channel, we analyze the basic access mechanism of IEEE 802.11 WLAN and derive the expressions of the saturation throughput and the conditional collision probability.The results from the model are verified by Network Simulation. In this paper,the impact of hidden nodes analysis algorithm proposed for improving the accuracy of network analysis has a certain theoretical value and practical significance.