Research And Implementation Of Handoff Control In Heterogeneous Network

Nowadays, heterogeneous network is gradually becoming a main form of telecommunicationnetwork, and the heterogeneous converging of3G-WLAN is the most representative modus in thiscircumstances. While3G-Network can provide global coverage with low data-rate, WLAN canprovide high data-rate service only within hot spots, therefore the convergence of3G network andWLAN network can complement each other perfectly. Performance optimization of theheterogeneous network has become a hot topic in the telecommunication field. This thesis focuseson the study and implementation of the handoff control system in3G-WLAN heterogeneousnetwork.First of all, this thesis analysis the switching requirements and characteristics in heterogeneousnetwork, and specifically studies on the handoff control technology in IMS-based3G-WLANheterogeneous network. Based on the previous study, the thesis proposes a handoff control schemewhich integrates forced handoff and optimized handoff, and a handoff implementation schemebased on security requirements. Then, a handoff control system is designed and developed. Adetailed description of the system is given in this thesis, including access control functioncomponents modules and function supporting modules such as initial threads scheduling, messagessending and receiving, encoding and decoding, and so on. Finally, this thesis gives the testingresults of the system, which show that the designed handoff control system is able to switch theaccess technology between3G and WLAN.