In Chapter 5, we propose a RMI estimation scheme to represent the mobility pat-tern of MS. We first provide a system model to simulate a urban environment. In this model, we introduce some new additional path loss models used in IEEE 802.16j networks. Second, we mixed RSSI and RMI into a Time-of-Arrival based target se-lection scheme. At the last, we compare the handoff performance (handoff frequency) between conventional target selection scheme and proposed scheme to proof that the proposed scheme is better than conventional method.
6.3 Suggestion for Future Work
For the future research of the thesis, we provide the following suggestions to extend our work:
• Consider others optional handoff scheme like Fast Base Station Switch (FBSS) and Macro Diversity Handoff (MDHO).
• Study how the proposed approach influences the performance of upper layer pro-tocol, such as ARQ efficiency, packet throughput, QoS, sleep mode power saving, etc. This could be helpful for real system design.
CHAPTER 6. Concluding Remarks 61
• Consider the tree-based structure of IEEE 802.16j multi-hop relay network, we care about the handoff latency on MAC layer.
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Vita
Cheng-Min Chen was born in Taiwan in 1972. He received the B.S. degree in the Department of Nuclear Engineering and Engineering Physics from National Tsing Hua University, HsinChu, Taiwan in 1996. He obtained his M.S. degree in the Wireless Network Lab. of the Department of Communication Engineering at National Chiao Tung University in Auguest of 2008. From July 2000 to present, he has been a researcher in Telecommunication Laboratories (TL) of Chunghwa Telecom Co., Ltd.
(CHT). His research interests are in the fields of wireless communication systems, mobile application, VoIP, IMS, queuing network, etc. You can contact with him via e-mail: [email protected].