Performance Evaluation of Quasi-Synchronous MC/CDMA System

• Main Authors: Bo-Xian Lin, 林博賢
• Other Authors: Szu-Lin Su
• Format: Others
• Language: en_US
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/95615218249282110746

碩士 === 國立成功大學 === 電機工程學系 === 87 === The multicarrier (MC) modulation is an effective technique in mobile radio communications in order to achieve high spectral efficiency and to combat the frequency selective fading of the channel. Code division multiple access (CDMA) can offer higher capacity than those achieved by other conventional multiple access techniques. Combining MC and CDMA techniques for mobile radio transmission can provide enhanced anti-multipath and anti-fading capabilities of the multiple access systems. In this thesis, the uplink performance of the MC/CDMA mobile radio systems using quadrature amplitude modulation (QAM) is investigated under both additive white Gaussian noise (AWGN) and frequency selective Rayleigh fading channels. We found that the QAM/MC/CDMA systems are very sensitive to the time and frequency offsets among different users' signals, so at least a mechanism to get quasi-synchronization is required in order to utilize the QAM modulation technique in the MC/CDMA systems to achieve high system capacity.