在多基地台的環境下考量有限的回程網路容量之基地台叢集化研究

Abstract

在這篇論文中，為了處理細胞之間的干擾，我們在有限的回程網路容量及多細胞的環境下，研究基地台間的合作式傳輸及分群方法。為了提高系統的效能，我們採用信號對漏電噪聲比標準來當作我們線性編碼的設計。在本篇中，我們提出了一種分散式的合併演算法，使得基台間可以形成合作聯盟，同時也考慮了限的回程網路容量，並保持在細胞中的每個用戶的效能。此外，我們還提出了讓基地台的服務區域可以與鄰近的服務區域重疊，也就是表示了，每個基地台都可以屬於一個以上的聯盟，以利於進一步增強系統的效能。因為這種區域性重疊的方法，在細胞邊緣的用戶可以在這樣的環境中獲得更好的效能。模擬結果顯示，在與最佳的結果相比，我們提出的合併演算法仍就可以有不錯的效能。此外，當我們採用基地台群與群間可以重疊服務的方法時，系統的效能也會隨之得到提升。

In this thesis, aiming at manage the inter-cell interference (ICI), we study the problem of base station (BS) coordination and clustering in multicell environments with limited backhaul capacity. To improve the sum rate performance of the system, the signal-to-leakage-plus-noise ratio (SLNR) criterion is applied for linear precoder design. We propose a distributed merge algorithm to form BS coalitions (i.e. clusters) with limited backhaul constraint, with consideration of limited backhaul data transmission while maintaining the user sum rate in each cell. In addition, an overlapped clustering scheme, in which each BS may belong to more than one cluster, is proposed to further enhance the sum rate performance of the system. It is expected that the cell edge users can experience better signal-to-interference-plus noise ratio in the overlapped clustering environment. Simulation results demonstrate a good sum rate performance of the proposed BS clustering algorithm when compared to the optimal clustering, and show the performance improvement when applying the overlapped clustering.