正交頻分頻(OFDM)多工是具吸引力的無線通信技術，它屬於多載波調變的一種技術，提供相當高的頻譜效率和多路徑延遲擴散的耐受性並且不受頻率選擇性衰落通道和功率效率影響。因此，正交頻分頻(OFDM)被認定是高資料傳輸率的通信，並被廣泛部署在多種無線通信標準，如DVB和基於移動式的WiMAX之基礎上。
正交頻分頻(OFDM)是無線通訊常用的傳輸系統，有許多的優點，不過它也存在著PAPR過高的缺點，此問題會使功率放大器與量化器造成嚴重的問題，因此有許多學者提出降低PAPR的方法，其中有個方法PTS，由於它擁有不會破壞訊號以及很好的降低PAPR效能，所以在這篇論文主要是改善PTS來降低PAPR，此想法是將訊號分成實部與虛部來分別執行PTS，以求得到更佳的相位因子組合，因此得到更好的PAPR降低效果。

AS an attractive technology for wireless communications, Orthogonal Frequency Division Multiplexing (OFDM), which is one of multi-carrier modulation (MCM) techniques, offers a considerable high spectral efficiency, multipath delay
spread tolerance, immunity to the frequency selective fading channels and power efficiency. As a result, OFDM has been chosen for high data rate communications and has been widely deployed in many wireless communication standards such as Digital Video Broadcasting (DVB) and based mobile worldwide interoperability for microwave access (mobile WiMAX) based on OFDM access technology.
Orthogonal frequency division multiplexing(OFDM) is desirable technique of wireless communication. The high peak-to-average power ratio (PAPR) is a major disadvantage of OFDM signals. The methods of PAPR reduction, partial transmit sequence (PTS) is effective and uncomplicated. This is proposed to exhaustive search the all combination of phase factors to obtain optimal signal. The simulation results show that it achieves better performance of PAPR reduction than the conventional PTS.

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