摘要
負載不平衡的問題，在家庭基站的網路環境中是隨時都存在著的，因為使用者不是均勻分散在各地，並且是會移動的，當使用者在家庭基站之間做連接的選擇時，可能因為交通位置的關係，使得某些基地台較容易被選擇，而其他則否。這將會導致家庭基站網路中的資源分配不均勻。同時，在人潮流動的環境中，這問題是有可能會更加的嚴重的，對現有的使用者與未來可能連接的使用者來說，都是不公平的。為了解決這問題，本文提出了一個以馬可夫決策過程為基礎的負載平衡改善機制，在考慮負載平衡改善的同時也考慮了使用者對傳輸頻寬的需求，找出每次負載平衡改善的最大期望值，要求符合條件的使用者換手來達成負載平衡改善的目的。而根據模擬結果，本文提出的改善機制能較大幅度的改善負載不平衡的問題。

Abstract
The problem of load imbalance always exists in the femtocell environment. Because users would not evenly distributed and move around. In addition, when users choose the link between the femtocell, probably because the traffic or the location, making it easier for some femtocell is selected, while others did not. This situation will result in uneven distribution of resources in the femtocell network. Meanwhile, in the environment of the crowd flow, this problem may be more serious. This is not fair for existing users and possible link users.
In this thesis a Markov Decision Process based Load balancing scheme is proposed. We consider about the load balance improvement, and also consider about the user bandwidth demand. By finding the maximum expected value of load balancing improvement, Eligible users will be chosen to request handover. Finally, we can see the simulation results demonstrate that the proposed algorithm has a relatively large improvement.

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