用於異質性網路中加強版細胞間干擾協調之動態干擾抑制與負載平衡技術

Abstract

加強版細胞間干擾協調 (enhanced Inter-cell Interference Coordination, eICIC) 為異質性網路中抑制干擾問題最常用的技術之一。於本論文中，吾人研究在無線系統中有服務品質 (quality of service, QoS) 需求之動態加強版細胞間干擾協調機制。由於用戶移動性和流量動態的存在，動態加強版細胞間干擾協調機制在現代無線網路中成為不可或缺。具備了服務品質需求，用戶可以在動態加強版細胞間干擾協調機制下有效地利用系統的資源。為了在不同情況下評估系統性能，吞吐量和公平性被選為評量的指標。吾人首先使用一改良過的總吞吐量效用 (utility) 作為吞吐量指標，並針對系統總吞吐量最大化提出一動態加強版細胞間干擾協調策略。接著吾人選擇一比例公平效用作為公平性指標，並針對比例公平的最大化提出一動態加強版細胞間干擾協調策略。最後，電腦模擬結果顯示，服務品質需求下之動態加強版細胞間干擾協調機制在不同情景中的表現，比靜態加強版細胞間干擾協調機制和傳統動態加強版細胞間干擾協調機制較佳。

Enhanced Inter-cell Interference Coordination (eICIC) is one of the most popular techniques used to mitigate the interference problem in heterogeneous networks. This thesis investigates the dynamic eICIC mechanism with quality of service (QoS) requirements in wireless communication systems. Because of the user mobility and traffic dynamics, the dynamic eICIC mechanism is necessary in modern wireless networks. With QoS requirements, users could utilize the system resources efficiently under the dynamic eICIC mechanism. In order to evaluate the system performance in different aspects, the throughput and fairness are selected as the metrics. We firstly use a modified sum-rate utility as the throughput metric, and propose a dynamic eICIC strategy for the system sum throughput maximization. Then we choose a proportional fairness utility as the fairness metric, and propose a dynamic eICIC strategy for proportional fairness maximization. Finally, computer simulations show that the performance of the dynamic eICIC mechanism with QoS requirements is better than the static eICIC mechanism and conventional dynamic eICIC mechanism in different scenarios.