A Common Carrier Frequency Offset Compensation Method for Multiple Access Interference Reduction in OFDMA Systems

• Main Authors: Yeh-Tang Chang, 張譽騰
• Other Authors: 張大中
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/92666324274646731463

碩士 === 國立中央大學 === 通訊工程研究所 === 95 === In recent years, the orthogonal frequency division multiple access (OFDMA) system has been viewed as a principal technique for future worldwide wireless networks. But in such a system, carrier frequency offset (CFO) can destroy the orthogonality among all subcarriers and induce inter-carrier interference. While in multiple accessing applications, different CFO misalignments exist in multiusers, which cannot be compensated simultaneously. This result is considered as multiple access interference (MAI). However, MAI can be reduced by using parallel compensation systems for different users at the basestation side and thus, a circular deconvolution solution has been proposed after the fast Fourier transform (FFT) operation. Since the effect of MAI is related to the value of CFO, a common CFO compensation method is studied in this paper to regulate MAI’s for a group of users whose performance may be interested in some TDMA slot. Simulation results show that the proposed method can achieve required results.