IEEE 802.16j工作小組所制定發展的多躍式中繼(multihop relay)技術主要是根據IEEE 802.16e標準，其目標為使用較低成本的透通性或非透通性中繼站，藉以增加系統的傳輸量(throughput)或擴展基地台的服務範圍(coverage extension)。由於透通性中繼站只轉送基地台的訊號，行動台並無法識別透通性中繼站，因此無法使用IEEE 802.16e所定義的基地台間換手機制。為了解決此問題， IEEE 802.16j規格制定了兩種中繼站量測回報模式，讓基地台可藉由中繼站的回報來協助行動台換手，讓行動台移動時可獲得最佳的信號品質。
本論文將針對使用透通性中繼站的多躍中繼系統，探討行動台在單一基地台涵蓋範圍下的透通性中繼站之間移動的換手效能。吾人依據規格中所定義的兩種中繼站回報模式，考量中繼站的佈建方式、中繼站轉傳增益、行動台的移動速度以及回報模式與換手條件參數之設定，分別考慮路徑衰減與遮蔽效應的影響來評估不同設定條件所造成的傳輸增益以及所需的管理訊息量，相關成果將可提供系統業者於多躍中繼系統佈建時的參考。

Multi-hop relay (MR) is a multi-hop communication technique developed by IEEE 802.16 task group j (TG j), it aims to enhance coverage, throughput and system capacity of 802.16-based wireless broadband access networks via using relay stations (RSs). The newly introduced RSs result in an RS-involved handover problem. Two RS report modes are defined in 802.16j to support the movement of mobile station (MS) among transparent relay stations. However, the selection of the report mode and the setting of the mode-related parameters are out of the scope of 802.16j specification. In this paper, we propose methods to set the related parameters and then investigate performance of the two RS report modes.

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