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Performance of VoIP Over IEEE 802.11g DSSS-OFDM Mode With IEEE 802.11e QoS Support

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24 out of 46 users found this white paper useful


Publisher University College Dublin
Publisher Registration N/A
Topics Wireless LAN, Mobile - Wireless Communications, Wi-Fi (802.11) Date added 18 Mar 2005
Downloads 86 Format 104.5KB PDF

This paper examines, via simulation, the performance of an 802.11e MAC over an 802.11g PHY operating in DSSS-OFDM mode. The DSSS-OFDM scheme provides data rates of up to 54Mb/s as well as interoperability with 802.11b nodes. Due to the widespread use of 802.11b nodes, such interoperability is an important consideration. This paper involves a study of the number of simultaneous bidirectional G.711 VoIP calls that can be supported by such a WLAN. The results show that this mode of operation introduces a very significant overhead. The actual number of calls that can be carried is limited to 12 when using the 24Mb/s data rate and 13 when using either the 36Mb/s or 54Mb/s rates.

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24 out of 46 users found this white paper useful


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