於上行傳輸多點協調系統中利用混合型干擾校齊之收發器設計

Abstract

在蜂巢式系統下，為了使覆蓋範圍內的使用者皆能享有均勻的資料吞吐量及高傳輸速率，第三代合作夥伴(third generation partnership project; 3GPP)在前瞻長程演進系統(long term evolution-advanced; LTE-A)中提出新穎的多點協調(coordinated multipoint; CoMP)傳輸與接收技術，以提升細胞邊緣(cell-edge)使用者的服務品質(quality of service ; QoS)，進而增進系統效能。在本篇論文中，吾人於上行傳輸協調系統中引入干擾校齊(interference alignment; IA)技術，基地台之間的合作可透過後置網路(backhaul)交換資訊以達到抑制干擾的目的，進而提升系統容量。吾人提出疊代式的最大信號洩漏雜訊比(signal-to-leakage-plus-noise ratio; SLNR)干擾校齊演算法，並進一步將其與最大信號雜訊干擾比(signal-to-interference-plus-noise ratio; SINR)干擾校齊演算法結合，即為混合型干擾校齊機制。經由模擬驗證，在集中式多點協調系統的協作下，相較於傳統的方法，吾人所提出的機制具有快速收斂特性且能大幅改進系統效能。

The demand for high data rate and uniform throughput for cellular user terminals in the cell coverage leads to a new coordinated multipoint (CoMP) transmission and reception technique proposed by the 3GPP LTE-A system. System performance can be enhanced by improving the quality of service (QoS) for cell-edge users. In this thesis, we incorporate the recently proposed interference alignment (IA) techniques in uplink CoMP to improve system capacity by leveraging the full cooperation and information exchange via the backhaul at the base stations. We propose a new iterative relaxed maximum signal-to-leakage-plus-noise ratio (SLNR) IA criterion and further combine it with the maximum signal-to-interference-plus-noise ratio (SINR) IA criterion to form a mixed-criteria IA-aided CoMP scheme. The proposed new criteria exhibit excellent convergence behaviors and provide substantial performance gain over conventional CoMP, thanks to the joint processing advantage in centralized CoMP. The effectiveness of the proposed scheme is confirmed by computer simulations.