A Decentralized Coordination Packet Reservation Multiple Access (DC-PRMA) Protocol for VoIP Service in Wireless LAN

• Main Authors: Min-Hua Chang, 張敏華
• Other Authors: Jean-Lien Chen Wu
• Format: Others
• Language: en_US
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/43035175662838634315

碩士 === 國立臺灣科技大學 === 電子工程系 === 93 === Voice over Internet Protocol (VoIP) in wireless local area network (WLAN) is an emerging Internet application. VoIP services provide lower cost than Public Swhiched Telephone Network (PSTN). This thesis proposes the Decentralized Coordination Packet Reservation Multiple Access (DC-PRMA) scheme to increase the number of voice calls that can be supported in WLAN. DC-PRMA extends the concept of the Packet Reservation Multiple Access (PRMA) in WLANs. In DC-PRMA, wireless channel is divided into superframes. A superframe is the composite of voice phase and data phase. Voice phase provides reservation resources for voice users. Users in data phase access channel by the Distributed Coordinator Function (DCF) mechanism. Consider the potential hidden terminal problem and multi-rate characteristic in WLAN, an adaptive slot reservation is employed in DC-PRMA. The performance of DC-PRMA is investigated by computer simulations in comparison with legacy IEEE 802.11. The results show that the DC-PRMA scheme can indeed provide more voice calls than legacy IEEE 802.11 while the QoS requirements of voice calls are guaranteed.