在長期演進技術升級版(Long Term Evolution-Advanced, LTE-A) 環境下，載波聚合為提升系統可供應最大速率的關鍵技術，可讓使用者以聚合多個單元載波來大幅提升傳輸速率。本論文專注於載波聚合技術部分，提出的方法為找尋最小分配的載波數使用量，藉由反覆聚合多個在此時最少可聚合的載波數的載波集合以提升系統的頻寬使用，同時可讓更多的使用者需求被服務到。我們證明了此問題為NP-Hard 問題，並推導了貪婪演算法以實作方法。藉由模擬結果可觀察出，本論文的方法在頻寬的使用與單元載波的使用量上比相近的文獻有更好的效果。

In the Long Term Evolution-Advanced (LTE-A) network, Carrier Aggregation (CA) is a key technique to enhance the total transmission rate by means of aggregating multiple component carriers (CCs). Focusing on CA, a scheme is proposed in this thesis to find the minimum number of allocated carriers through aggregating local minimum allocated carriers repeatedly to improve the usage of system bandwidth so that more service requests can be granted accordingly. We prove that the problem we considered is NP-hard. Therefore, a greedy algorithm is then utilized to find the solution. Via simulations, we show that our scheme works better than a closely related scheme in the literature in terms of bandwidth consumed and number of CCs used.

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