MC-CDMA系统载波同步性能分析与仿真

将载波同步误差综合到端到端的系统传递函数中,得到一个等效时变滤波器,进而分析载波同步误差对MC—CDMA系统性能的影响,给出了系统接收信噪比和误码率公式,并对载频偏移、载波相位抖动、时钟频率偏差及定时抖动对系统信噪比下降和比特误码率的影响做了全面、细致的分析与仿真。仿真结果验证了理论分析得出的结论,即MC—CDMA系统对载波同步误差非常敏感。在载波频率偏移或时钟频率偏移作用下,系统性能呈迅速下降趋势,并且严重依赖于载波数量。

Carr ier Synchronous Performance Ana lysis and Smi ulat ionofMC-CDMA System

Carrier synchronization errors are incorporated in the end-to-end transfer function and a time-varying equivalent filter is obtained. Then the synchronous performance of MC-CDMA system has been analyzed by means of the time-varying equivalent filter. The expressions of signal-to-noise ratio (SNR) and bit-error-ratio (BER) are presented and the effect of carrier frequency offset, carrier phase jitter, clock frequency offset and timing jitter on degradation of SNR and BER is analyzed and simulated thoroughly and precisely. Finally, academic conclusions are testified by computer simulation whose results show that the performance of MC-CDMA system is very sensitive to synchronization errors. The MC-CDMA performance in the presence of a carrier frequency offset or a clock frequency offset is a rapidly decreasing function of the number of carriers.