異質性網路環境下的基地台選擇與功率控制

Base Station Selection and Power Control in Heterogeneous Network

向賢祥(Hsien-Hsiang Hsiang)

指導教授 ： 林宗男

國立臺灣大學/電機資訊學院/電信工程學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.10011

摘要

異質性網路(heterogeneous network)中，如何選擇基地台(base station selection)和功率控制(power control)扮演著重要的角色，由於基地台使用者收到來自附近的家庭基站的干擾interference)隨著家庭基站的增加而增加所以面臨的挑戰也隨之成長。家庭基站是一種低功率、距離短而且極低成本的無線存取點(access point)。它們可以用來提升室內無限訊號的覆蓋率以及減少基地台的使用人數進而提升基地台使用者的速率。然而這些好處並不容易被實現，原因在於處在異質性網路中使用者可能被多個基地台所覆蓋，在這種情況下基地台的選擇以及功率控制就顯得相當重要。在這篇論文中我們提出了一個在異質性網路中集中式運算的基地台選擇和功率控制方法使整個網路效率最佳化的。

我們用最佳化的模型表示基地台選擇和功率控制的問題並且使用
分解的方法(decomposition method)和粒子群最佳化(particle swarm optimization)來解決所提出的問題，模擬結果顯示經由我們所提出的基地台選擇和功率控制方案可提升整個網路的效能。此外，經由我們利用粒子群最佳化可以在短時間內得到理想的功率控制以及基地台選擇且效能確實獲得顯著提升。

關鍵字

異質性網路 ； 家庭基站 ； 功率控制 ； 基地台選擇 ； 粒子群最佳化

並列摘要

In a heterogeneous network, the role of base station selection and power control become more important, but technical challenges also increase, because the macrocell users, su ering from severe interference from nearby cells, will naturally grow. The femtocells are low power, short-range and extremely low cost access points with third
party backhaul (e.g. DSL or cable modem). They have been considered by wireless industry as a solution not only improve indoor coverage, but also o oad tra c from macrocells. However, these bene ts are not easy to perform, base station selection and power control are required in the overlapping area design in heterogeneous network to maintain system performance. In this paper, we proposed
a centralized base station selection and power control scheme focus on improving the system capacity in heterogeneous network. We model the base station selection issue as an optimization problem for maximum the overall performance and employ decomposition method to solve the problem. Simulation results demonstrate that aggregate
capacity improved through our proposed base station selection and power control scheme. Moreover, our proposed power control scheme can converge very fast with a typical value of only ten iterations and it can achieve around seven percent extra capacity than xed power control scheme.

並列關鍵字

heterogeneous network ； femtocell ； power control ； base station selection ； particle swarm optimization

參考文獻

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