Studies Of The Voice Quality Based On IEEE802.11E Wlen

With the development of modern socio-economic and technological, the quality of people’slives is getting better. The wired network can no longer satisfy people’s demand gradually, so thewireless network will be more widely used. At present, the WLAN has rapidly integrated intoour lives as a strong expansion of the wired network. People are eager to enhance the voicequality of the WLAN, in order to provide the quality as stable and efficient as wired LAN.IEEE802.11is the most widely used protocol in the WLAN. In many aspects,802.11e is superiorthan802.11. Firstly,802.11e protocol provides support for QoS, Secondly,802.11e candistinguish different service priorities, and finally802.11e can provide higher-quality real-timedata transmission services.802.11e represents the direction of development of the network. Inthe wireless multimedia transmission, the correct assessment of voice quality based onIEEE802.11e WLAN is particularly important.There are many methods to assess voice performance, including the subjective voiceassessment method and the objective voice assessment method. The expense and complexity ofthe subjective assessment method makes it limited to application. The objective assessmentmethod is mainly used in the traditional telephone network. In this paper we study theIEEE802.11e protocol and the voice quality assessment method, and propose a new model. Themain contributions of the work are summarized as follows:1. Introducing the knowledge of IEEE802.11e WLAN, including networking, exponentialbackoff, service differentiation mechanism, virtual slot and advantages, the prospects for thedevelopment, application areas.2. Comparing these subjective voice quality assessment methods with those objective voicequality assessment methods, and we see that unlike other objective assessment methods to beused for traditional phone network, the E-Model method can also assess the voice quality on thedata network.3. A new model which introduces the E-Model method for assessment of voice qualitybased on IEEE802.11e WLAN is proposed. These different models are compared through simulation analysis. The results show that the voice quality based on the proposed model is theclosest one to the true value of voice quality, and its assessment is accurate.4. A new expression of the collision probability is presented. The different collisionprobability is also compared with each other through simulation analysis. The results show thatthe proposed collision probability is more accurate.Finally, a simple summary is made and some future works are presented.