Effects of carrier frequency offset on the average effective SNR and the average BER for asynchronous MC-CDMA uplink systems with a guard period

摘要

This paper presents an analysis of asynchronous multicarrier-code division multiple access (MC-CDMA) systems over frequency-selective multipath fading channels when the carrier frequency offsets (CFOs) of all users are random variables and the frequency offset for the desired user is compensated. The effect of residual CFO on the average bit error rate (BER) is evaluated by the semi-analytical method, then the approximated BER performance is obtained as a closed-form expression. Moreover, the signal-to-noise ratio (SNR) loss caused by residual CFO is evaluated. Derived results show that the performance degradation due to residual frequency offset is negligible if the estimation error of CFO for the desired user is less than the normalized value of 10~(-1).