在正交分頻多工系統上透過組合法降低峰值對均值功率比與帶外功率散逸之研究

A STUDY OF REDUCING OUT-OF-BAND EMISSION AND PAPR BY HYBRID USAGE OF PRE-CODING WITH TAIL-TRACKING OR ZERO-FORCING IN OFDM SYSTEM

朱原平(Yuan-Ping Chu)

指導教授 ： 許超雲

大同大學/電機資訊學院/電機工程學系所/碩士(2011年)

摘要

正交分頻多工技術(簡稱OFDM)，是高效率的多載波調變技術的一種，能夠提供高速資料傳輸速率，當資料在子頻帶上被平行傳輸，其優點是能有效對抗多重路徑下的符元間干擾和頻率選擇性衰減問題，但這項技術也有其缺點為會產生較高的峰均值功率比(簡稱PAPR)與高帶外功率的問題，許多研究提出方法來降低較高的峰均值功率比(簡稱PAPR)與高帶外功率，例如降低PAPR的方法:預先編碼法(簡稱Precoding)與降低高帶外功率的方法:尾隨法、強迫為零。
本篇論文在探討藉由預先編碼法矩陣並結合尾隨法、強迫為零法,來達到降低較高的峰均值功率比的同時也可以降低高帶外功率的問題。
由模擬結果顯示，將預先編碼法結合尾隨法、強迫為零法，同時在降低較高的峰均值功率比與高帶外功率，有顯著的差異。

關鍵字

正交分頻多工技術 ； 帶外功率 ； 峰均值功率比

並列摘要

Orthogonal Frequency Division Multiplexing (OFDM) system is one kind of multi-carriers modulation technique for high data rate transmission. The data are transmitted in many parallel sub-carriers. It is robustly to multipath interference by means of symbol guard interval, but it is suffered from the problems of high Peak-to-Average Power Ratio (PAPR) and Out-of-Band power emission. There are many approaches to reduce Peak-to-Average Power Ratio (PAPR), such as Pre-Coding method, and there are also many approaches to reduce Out-of-Band power emission, such as Zero-Forcing and Tail-Tracking methods.
This thesis will discuss the variant methods by preceding Pre-Coding matrix with Zero-Forcing and Tail-Tracking methods to reduce the PAPR and Out-of-Band power emission.
The results of simulation show that the hybrid methods can reduce the PAPR and Out-of-Band power emission simultaneously.

並列關鍵字

PAPR ； Out-of-Band ； OFDM

參考文獻

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