Research On The Key Technologies Of Emergency Communication Systems Backbone With 802.11n

Due to the variability of topography, geological disasters strike easily in our country. In the geological disaster rescue site, field information often needs to be transported immediately. Therefore, a quick network is required in the field.First, this paper puts forward a scheme for the emergency communication network based on 802.11n and wireless Mesh network technology, and analyzes the TXD/RXD of 802.11n protocol and MIMO channel model. Based on these analyses, the optimum data sending solution is designed and validated by Maltab. Then, this paper discusses the emergency communication network backbone, studies its bandwidth needing in multi-hops, analyzes the main factors of mutil-hops degradation, and summarizes the fast networking and network monitoring technology in the emergency communication environment. Finally, to validate its performance, a series of experiences are conducted on this test-bed, which is constructed based on embedded system. The experimental results show that 802.11n for the wrieless backbone can provide 140Mbps benchmark bandwidth and still can reach more than 75Mbps transmission bandwidth after 8 hops. In the real-world environments with limited speed, the transmission bandwidth is more than 55Mbps after 8 hops, and average bandwidth degradation is less than 2%. In addition, the experimental study also found that CPU packet processing power and other hardware performance are no longer the the main factor for the degration of network performances, while radio interference factor shows more influence.