A Frame Aggregation Scheme With Service Differentiation For Next Generation Ultra High Speed WLAN Technology

Wireless LAN technology, has been integrated into all aspects of our daily life, byvirtue of its irreplaceable advantages. February24,2012, China’s Ministry of Industryand Information Technology announced approval of the high spectrum efficiency andengage in data throughput of wireless LAN technology requirements-Part1:ultra-high-speed wireless LAN Medium Access Control (MAC) layer and physicallayer(PHY)"two communication industry standards, that this research mainly technicalbackground: The next generation of ultra-high-speed wireless LAN technology. Thenext generation of ultra-high-speed wireless LAN has a very significant increase in thespectral efficiency of the transmission rate of the physical layer and MAC layerthroughput performance. It developed with independent intellectual property rights andefficient in the short-distance communication system as the main research goals, thesystem would be expected to support a large number of high-speed connections in shortdistance. The standard by improving the physical layer and MAC layer accesstechnology, after the use of cognitive radio and band aggregation technology, thehighest throughput can achieve1.2Gbps.The next generation of ultra-high-speed WLAN access mechanism is a centralizedscheduling-based, competitive access supplemented by such a system throughput boththe BE business agility access mechanism. In view of this situation, only consider themodel of centralized scheduling access, the article proposes a distinction betweenbusiness as frame aggregation strategy of business QoS levels, the average arrival rateof the business, the queue delay the degree of urgency and statistical average arrival rateof the current business main parameters, combined with the mathematical model ofqueuing theory, the use of non-symmetry, the queue limited capacity bulk service modelas well as fixed services processing business queue, and eventually come to each queueaggregate weight values, Aggregation module that is in accordance with the weight ofthe polymerization of the queue on the business queue polymerization, polymerizationweights queue packets of each business in a polymerization percentage of frame. Thisscheduling and aggregation model can guarantee the need of QoS priority business, while reducing some redundant overhead of the header, interframe interval. Ultimately,simulations show that the differentiated service the frame aggregation model can givepriority to ensuring the high priority traffic, and have obvious advantages than notdistinguish classic round-robin scheduling on queue overflow rate, average queue lengthindicators. However, the model performance in the low arrival rate environment wasrelatively poor, in view of this situation, the paper proposes an improved triggermechanism, and finally shows the effectiveness of the measures through the simulation.Ultimately, we build a simple model for the next generation of ultra-high-speedwireless LAN MAC layer in OPNET simulation platform. Simulate the main function,such as MAC layer service streams create, modify, delete, bandwidth application(slightly separate request in two ways) function, service queuemaintenance,aggregation, immediately ACK (block ACK and single frame ACK), andautomatic retransmission, fragmentation and reassembly, and verified the effectivenessof the distinguish business queue frame aggregation strategy on this platform.