正交分頻多工系統頻率偏移估計之研究

A Study of OFDM Frequency Offset Estimation

黃健輔(Chien-Fu Haung)

指導教授 ： 鄭立德

中原大學/工學院/電子工程研究所/碩士(2005年)

https://doi.org/10.6840/cycu200500796

摘要

正交分頻多工系統以高傳輸資料量與抵抗衰減通道的優異性能，使
其在近幾年的通訊系統發展中，廣泛地應用在數位電視、數位廣播與無線
網路等領域。但在正交分頻多工系統的通訊過程中，對於頻率偏移有很
高的敏感度，容易造成正交分頻多工系統中各個子載波失去正交性，而
喪失了原有的優異通訊性能。有鑑於頻率偏移問題對正交分頻多工系統
的重要性，本篇論文討論兩種不同的盲目型正交分頻多工系統之頻率偏
移估計方法，針對這些方法所使用的資源、通道情況、估計方法計算量與
通訊效能來做比較。最後，提出對於正交分頻多工系統所使用之頻率偏
移估計方法的建議。期望能對於將來想研究此一領域的同好有所助益。

關鍵字

估計 ； 正交分頻多工系統 ； 頻率偏移 ； 衰減通道 ； 離散傅利葉轉換

並列摘要

In virtue of the outstanding performance of high data rate and fading
channel resistance, OFDM is broadly applied to DVB, DAB, and Wireless
LAN recently during the development of communication system. However,
OFDM is highly sensitive to carrier frequency offset, which may easily cause
each subcarrier in the system to lose orthogonality and therefore lose its original
outstanding performance. Owing to the importance of carrier frequency
offset to OFDM, this paper will discuss different blind estimation methods
of OFDM with carrier frequency offset. Various resources such as channel
type, complexity of estimation method and performance will be compared.
This paper will be ended in the suggestion of frequency offset estimation of
OFDM. This research is done under the expectation to be beneficial to future
studies for the researchers who have the same interests in this field.

並列關鍵字

frequency offset ； OFDM ； fading channel ； DFT ； estimation

參考文獻

[2] B. chen, H. Wang,“ Blind estimation of OFDM carrier frequency o®set

via oversampling,”IEEE Trans. Signal Processing, vol. 52, pp. 2047-

for OFDM signals transmitted over multipath fading channels,” IEEE

[4] H. Liu, U.Tureli, “ A high-e±ciency carrier estimator for OFDM

likelihood blind carrier o®set estimator for OFDM systems,” IEEE