微型基地台網路之佈局分析與效能估計

Abstract

在這篇論文中，我們將討論如何利用微型基地台網路來增進蜂巢式無線通訊系統的效能。微型基地台可以由一般使用者放置在任何地方 ，以增加通訊系統覆蓋率或是提升使用者的網路頻寬。但是微型基地台也為蜂巢式通訊系統帶來了新的問題。在我們的研究當中，我們提出提供使用者完整的系統覆蓋率為目標，調整微型基地台在空間當中的”密度”的想法。我們建立一個三維立體空間的隨機網路模型以及四類干擾情況。在每一類干擾情況下，我們分析微型基地台網路所容許的密度區間。在 4G 無線通訊系統的架構之下，我們也提供了一個可以快速估計微型基地台網路傳輸頻寬的估計方法。因此，我們的研究成果可直接應用於無線通訊系統對微型基地台網路的資源配置以及使用者端的服務品質控制。除了微型基地台網路外，我們的研究成果和數學分析還可以延伸應用在無線通訊的其他問題。在我們的論文當中，我們也提出了1) m 維的隨機網路, 和2) Nakagami fading channel 的 fading figure 估計方法, 兩項延伸應用。

In this dissertation, we will analyze how to improve the cellular wireless communication system through the help of femto base station (femto BS) networks. Femto BS is a base station which provides much smaller coverage area and users can deploy femto BSs on locations where they want to improve the Quallity of Service (QoS). To ensure a proper downlink outage probability, design criterion based on a feasible femto base station (BS) density is analyzed. Considering femto BS deployment, a three-dimensional (3-D) Poisson model of random spatial distribution and stochastic geometry are used. From the study, closed forms of feasible femto BS density will be identified. Based on the frame structure of 4G cellular communication system, we also provide a fast approach to estimate the achievable throughput that user will obtain from femto BS networks. The analysis results not only can be used to predict the performance of various femto BS deployment scenarios but also can be used as a design criterion for resource control mechanism designs. Our research results about femto BS network can also be applied to other research topics of wireless communications. In our study, we further extend our study to the m-dimensional random networks and the fading figure estimation of Nakagami fading channel.