title: Motion adaptive vertical handoff in cellular/WLAN heterogeneous wireless network.
abstract: In heterogeneous wireless network, vertical handoff plays an important role for guaranteeing quality of service and overall performance of network. Conventional vertical handoff trigger schemes are mostly developed from horizontal handoff in homogeneous cellular network. Basically, they can be summarized as hysteresis-based and dwelling-timer-based algorithms, which are reliable on avoiding unnecessary handoff caused by the terminals dwelling at the edge of WLAN coverage. However, the coverage of WLAN is much smaller compared with cellular network, while the motion types of terminals can be various in a typical outdoor scenario. As a result, traditional algorithms are less effective in avoiding unnecessary handoff triggered by vehicle-borne terminals with various speeds. Besides that, hysteresis and dwelling-timer thresholds usually need to be modified to satisfy different channel environments. For solving this problem, a vertical handoff algorithm based on Q-learning is proposed in this paper. Q-learning can provide the decider with self-adaptive ability for handling the terminals' handoff requests with different motion types and channel conditions. Meanwhile, Neural Fuzzy Inference System (NFIS) is embedded to retain a continuous perception of the state space. Simulation results verify that the proposed algorithm can achieve lower unnecessary handoff probability compared with the other two conventional algorithms.
authors.affiliation: CRC, School of Electronics and Information Engineering, Harbin Institute of Technology, Nan Gang District, Harbin 150001, China.
authors.forename: Limin
authors.identifier: 0000-0002-9198-6973
authors.initials: L
authors.lastname: Li
authors.affiliation: CRC, School of Electronics and Information Engineering, Harbin Institute of Technology, Nan Gang District, Harbin 150001, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Ma
authors.affiliation: CRC, School of Electronics and Information Engineering, Harbin Institute of Technology, Nan Gang District, Harbin 150001, China.
authors.forename: Yubin
authors.initials: Y
authors.lastname: Xu
authors.affiliation: CRC, School of Electronics and Information Engineering, Harbin Institute of Technology, Nan Gang District, Harbin 150001, China.
authors.forename: Yunhai
authors.initials: Y
authors.lastname: Fu
mesh_terms: D000465:Algorithms; D040421:Cell Phone; D003195:Computer Communication Networks; D017143:Fuzzy Logic; D016247:Information Storage and Retrieval / Q000379:methods*; D016571:Neural Networks, Computer; D012815:Signal Processing, Computer-Assisted; D059015:Wireless Technology