考量LTE-A網路多天線及協同式傳輸之資源排程設計

Abstract

3GPP LTE-A (Long Term Evolution-Advanced，長期演進技術) 是目前最受推崇的4G無線通訊標準之一，其支援多進多出的多天線傳輸技術及多細胞的協同傳輸能力，可改善細胞邊緣(cell-edge)訊號衰弱的問題，並提高細胞中心(cell-center)的吞吐量。至目前為止，多數的文獻皆只單獨探討單一細胞下之多天線傳輸技術，亦或探討多細胞下之單一天線協同傳輸技術，至於多細胞下之多天線傳輸管理仍是一項開放性的議題。因此，本篇論文首先定義此多細胞多天線的資源排程問題。接著，我們提出一個低複雜度的群集式資源配置方法，該方法共包含兩階段：第一階段中，我們根據一套傳輸效益法則，將用戶依可使用的傳輸技術作分群，如此可加快 用戶之傳輸機制的決定。第二階段中，我們採用一個Greedy方式，挑選具有較高傳送效益之用戶群，以決定資源分配的順序及大小，如此可加快滿足用戶的需求及並提高資源利用率。模擬結果顯示，我們提出的方法在環境干擾強弱不一的情況下，除了能滿足用戶的需求外，同時具有近似於最佳解的系統吞吐量，而所花費的運算成本卻不到最佳解的二分之一。

3GPP LTE-A (Long Term Evolution-Advanced) is one of most popular 4G communication standard, it possesses multi-antennas transmission technical which supported MIMO (multi-input and multi-output) and capable of CoMP (coordinated multi-point transmission), the whole network throughput is increased substantially. Currently, the majority papers addressed resource scheduler for single cell with multi-antenna or multi-cell with single antenna, as to multi-antenna with multi-cell scheduler co-operation, it is still an open issue. In this paper, we mathematical modeling multi-antenna with multi-cell, After that, we proposed a low complexity of clustering scheduler methodology, which is including two stages. First, we group subscribers base on usable transmission technical. Second stage, we introduce Greedy to pick and scheduler the group which have higher transmission rate for increases resource utilization and satisfaction. According to simulation result, our heuristic not only approach optimal capacity under various noise circumstance but cost reduced substantially.