Performance Evaluation and Improvement of the CE-OFDM-PM System

• Main Authors: Ji-Wei Lin, 林季緯
• Other Authors: 呂振森
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/99tqtf

碩士 === 國立臺北科技大學 === 電機工程系研究所 === 96 === This thesis focuses on the performance evaluation and improvement of the Constant Envelope-Orthogonal Frequency Division Multiplexing-Phase Modulation (CE-OFDM-PM) system. The conventional OFDM systems suffer the problems of high peak-to-average power ratio (PAPR). The probability of the OFDM system with high PAPR increases as the number of subcarriers increases. However, this phenomenon of OFDM systems results in the nonlinear distortion of output signal of high power amplifier. Thus the CE-OFDM-PM system which combines both PM and OFDM techniques was proposed. The CE-OFDM-PM system transmits the OFDM signal by phase modulation. Since the PM system has a constant envelope, it can avoid the problem of high PAPR in the OFDM system. In this thesis, we analyze the performance of CE-OFDM-PM system and propose an improved one. By combining the peak cancellation technique in OFDM, our proposed system has lower bit error rate than that of original one under the same transmission bandwidth.