隨著行動通訊的發展及普及，現在人們對於資訊的速度及品質要求日益增加。無線網路技術演進之今，LTE（Long Term Evolution）及LTE-Advanced已被公認為4G的移動通訊標準，高傳輸率、低延遲為此世代通訊的主要目標。
　　本論文建立在LTE-Advanced的異質網路環境，異質網路為在傳統的基地台覆蓋範圍內，加入一些低功率的小型基地台，如何有效地提升整體使用者的傳輸量為主要考量。3GPP為異質網路提出了eICIC（enhanced Inter-Cell Interference Coordination），其中包含CRE（Cell Range Expansion）及ABS（Almost Blank Subframe）兩種機制來解決跨層干擾問題，本文建立在此基礎上，提出二維的跨層干擾解決方案。其主要精神為利用大小基地台間對於不同頻段的喜好程度，在Macro-Cell部分保留傳輸效能較好的頻段，空出Pico-Cell傳輸效能較差的頻段已達到更好的傳輸品質與效能。

　　With the development of mobile communications, our requirement of speed and quality for information is increasing more and more. LTE(Long Term Evolution) and LTE-Advanced are recognized as the standard of ITU 4G. High performance and low latency are still the main target we want to achieve this years.
　　This paper is based on the environment of LTE-Advanced heterogeneous network. Heterogeneous network means that: In addition to the original BS (Base Station), we also put some LPNs (Low Power Nodes) to the environment. The purpose is improving the performance of UE (User Equipment) in cell edge or hot spot. Because of the novel setting of the environment, we get some new problem of the interference between the original BS called Macro-Cell and the LPNs called Pico-Cell or Femto-Cell. 3GPP propose eICIC (enhanced Inter-Cell Interference Coordination) technology to solve the cross-tier interference problem. There are two mechanism of eICIC: CRE (Cell Range Extension) and ABS (Almost Blank Subframe). In consideration of the premises, we propose Two-dimensional cross-tier interference avoidance mechanism. We consider the performance of different RB (Resource Block), Macro-Cell may reserve the RB which is Macro-Cell’s favorite and release the RB which is inefficient to the small cells’ transmission to get the more efficient transmission.

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