Enhancing Mobility Management for WiMAX

• Main Authors: Lin, Yung-Chun, 林湧鈞
• Other Authors: Lin, Yi-Bing
• Format: Others
• Language: en_US
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/16229671529251136679

博士 === 國立交通大學 === 資訊科學與工程研究所 === 98 === As mobile subscriber population rapidly grows, mobile access for broadband services becomes an important part of human life. IEEE 802.16e mobile Worldwide Interoperability for Microwave Access (WiMAX) provides broadband wireless services with wide service coverage, high data throughput, and high mobility. In WiMAX, mobility management (i.e., location management and handoff management) is one of the most important issues to support mobile services. Location management function tracks the roaming Mobile Stations (MSs) for service delivery, and handoff management function maintains service continuity during MS mobility. Such functions are important for mobile telephony services, including conference/video call and Push to Talk over Cellular (PoC). In this dissertation, we investigate the mobility management issues for WiMAX networks. For location management, we first propose an analytic model to study the Location Update (LU) performance with overlapping Location Area (LA) configuration. Our study indicates how to determine the appropriate overlap among LAs. Then we investigate the performance for WiMAX LU procedure with Anchor Paging Controller (APC) relocation. In WiMAX, an APC is assigned to an MS to handle its location tracking and can be dynamically relocated during the LU procedure. By the analytic results, we provide guidelines to utilize the APC relocation for MSs with various moving behaviors. For handoff management, to support service continuity for high mobility MSs, we proposed the Repacking on Demand (RoD) for the Hierarchical WiMAX Network (HWN) by considering the MS moving speeds. Our study quantitatively indicates that RoD is less sensitive to MS speeds and outperforms the other previous proposed schemes significantly. The research results presented in this dissertation provide some useful mechanisms and guidelines for WiMAX operators to achieve high system performance in their networks.