以迭代的平滑化截波與最佳化濾波 降低載波聚合中的峰均功率比

Iterative Smoothed Clipping and Optimized Filtering for PAPR Reduction of Carrier Aggregation

林淑萍(Shu-ping Lin)

指導教授 ： 陳永芳

國立中央大學/資訊電機學院/通訊工程學系/碩士(2015年)

摘要

近年來無線網路系統的快速發展，行動裝置的使用者也大幅增加，對於頻譜資源的需求極為迫切，由於缺乏大範圍的連續頻寬資源，第三代合作夥伴計劃（Third Generation Partnership Project, 3GPP）在LTE-Advanced系統中提出載波聚合（Carrier Aggregation, CA）這項技術，它用來聚合許多連續獲不連續的零碎頻譜，以提供大頻寬、達到更高峰值速率，但是聚合了更多的子載波，使得的訊號產生過高的峰均功率比（Peak-to-average Ratio, PAPR），過高的PAPR會使得整體系統的效能降低。
在眾多降低PAPR的方法中，迭代下的截波與濾波（Iterative Clipping and Filtering, ICF）是最容易實行的，但是會造成訊號的失真以致於系統無法完整的解回原始訊號，在本篇論文中根據ICF提出新的方法，它可以減少在截波的過程中所會造成的失真及使用CVX的軟體來最佳化濾波器的參數以達到最小的誤差向量幅度（Error Vector Magnitude），能夠更有效率的降低訊號的PAPR值。

關鍵字

長期演進技術 ； 載波聚合 ； 峰均功率比 ； 截波 ； 濾波

並列摘要

Due to the fast-growing wireless network system in recent years, the number of mobile users has increased significantly and the demand for spectrum resources is also urgent. Because of the lack of a wide range of continuous bandwidth, the Third Generation Partnership Project (3GPP) proposed carrier aggregation (CA) technology in LTE-Advanced system. CA can aggregate many contiguous or non-contiguous fragment spectrums for supporting widely bandwidth and higher peak data rate. However, aggregate a lot of subcarriers will generate high peak-to-average power ratio (PAPR) which makes the overall system performance degradation.
Among the existing PAPR reduction methods, Iterative Clipping and Filtering (ICF) is the easiest to implement, but ICF may cause signal distortion so that the system can not completely recover the processed signal to original signal. In this thesis, we proposed a new method based on ICF which can reduce the distortion caused by clipping, and using public convex software (CVX) to compute the optimized filter to achieve the minimum error vector magnitude and efficiently reduce PAPR for CA.

並列關鍵字

Long Term Evolution-Advanced (LTE-A) ； carrier aggregation (CA) ； peak-to-average power ratio (PAPR) ； Iterative Clipping and Filtering (ICF)

參考文獻

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