1. 1 後卓越計畫 進度報告 楊舜仁老師實驗室 2008.01.07

2. 2 Objective Investigate the bandwidth management mechanisms for IEEE 802.16j networks. The goal of bandwidth management increase system capacity increase bandwidth utilization increase system throughput reduce new connection blocking probability reduce handoff connection force-termination probability reduce the number of handoffs

3. 3 IEEE 802.16j Multihop Relay Network The main concept of multihop relay network is to establish relay stations (RS) as relay media between BSs and MSs. RS: lower power, smaller coverage (relay station cell, RS-cell) BS: higher power, larger coverage (base station cell, BS-cell)

4. 4 IEEE 802.16j Frame Structure for Data Transmission In IEEE 802.16 networks, each frame has a fixd duration. Each frame contains one downlink and one uplink subframe, and the frame is diveided into an integer number of physical time slots, which help to partition the bandwidth easily. In IEEE 802.16j, the downlink path includes BS to MS, BS to RS and RS to MS, while the uplink path includes MS to BS, RS to BS and MS to RS. The radio resource in IEEE 802.16j may be allotted to RSs in a pre-determined and fixed way. 100202510520

5. 5 Bandwidth Repacking x-y

6. 6 Problem Statement of Bandwidth Repacking Assume that there are idle time slots in RS-cell m, but no repacking candidates in RS-cell m due to no MS directly served by BS. no available time slots idle time slots

7. 7 Bandwidth Carrying (1) (2) under-loadedover-loaded