隨著科技的進步，人類對於傳輸速率與傳輸品質有著更高的需求，為了解決這個問題，有許多處理流量的有效方法被提出，例如: 提升基地台的硬體裝置、增加基地台的佈建、放置小型基地台…，增加基地台佈建與放置小型基地台都會產生內佈基地台間的互相干擾，enhanced Inter Cell Interference Coordination (eICIC)就被提出來解決異質網路間的干擾問題，本篇異質網路的定義為不同層級基地台混合而成的網路，由大型基地台(Macro)與小型基地台(Pico)所構成，然而，大型基地的功率較大，會對小型基地台的傳輸造成干擾，所以需使用eICIC來協調干擾，在eICIC中有兩項增加傳輸量的機制，其一是Cell Range Extension (CRE)，由於User Equipment(UE)是根據最大的接收參考功率( Reference signal receive power,RSRP)來決定連接哪個基地台，然而CRE在UE計算接收功率時加上一定的數值在接收小基地台的功率上，讓小基地台能服務更多的UE，另一個機制是Almost Blank Subframe (ABS)，由於小基地台傳輸時，UE會受到大基地台的干擾，就讓大基地台特定時間停止傳輸資料以減少對Pico UE干擾。
本篇論文主要探討包括CRE、ABS、及大型基地台降低傳輸功率(ReducePower)這三種機制在eICIC之應用及其互動之影響，並提出在UE移動環境下，上述三種機制之動態調整方法，並透過模擬以驗證所提出方法之效果，從模擬結果可看出，與其他方法相比，所提出方法更能因應UE通道品質變化，調節不同機制之參數設定，因而有較佳之效能。

As technology advances, the demands of transmission rate and transmission quality get higher. In order to solve this problem, many studies were proposed, such as proper base station placements, pico cells deployments, etc.. However, deployment of multiple macro and pico cells always causes interference with each other. Enhanced Inter Cell Interference Coordination (eICIC) was proposed as one of the possible solutions to deal with the interference in the macro/pico co-existence heterogeneous network. Generally, Macro cell will cause interference to the User Equipments (UEs) served by pico base station due to the high transmission power from macro base station. eICIC involves two mechanisms to improve total throughput, first is Cell Range Extension (CRE), UEs connect to the cell due to its reference signal receive power (RSRP). However, CRE add some specific value to calculating small cells power for more UEs serving by small cells. Another mechanism is Almost Blank Subframe (ABS), when small cells serving for UE would suffer interference form Macro cell, and ABS decrease the interference by stopping transfer traffic in specific times in macro cell.
This thesis studies the effects among the CRE, ABS, and the transmission power transmitted by the macro base station in eICIC and proposes the dynamic parameters adjustment algorithm of the above three mechanism for the moveable UE environment.Simulations were performed to investigate the performance of the proposed algorithm. The simulation results show that the proposed algorithm can effectively adjust the parameters of the above three mechanism and, therefore, has better throughput when comparing to the other schemes.

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