Error Rate Analysis of Uplink MC-CDMA Systems using Complementary Codes in Rayleigh Fading Channels

Complementary coded multicarrier code-division multiple access (CC MC-CDMA) has a strong potential to offer frequency diversity gain in frequency selective fading channels due to its ideal correlation characteristics. However, in uplink transmissions the use of single-user detection techniques will reduce the diversity gain achievable with complementary codes (CCs). Multiuser detection schemes such as successive interference cancellation (SIC) has a strong potential to overcome multiple access interference (MAI) in near-far environments. In this paper, SIC is analyzed in the context of improving the error rate performance of CC MC-CDMA operating under asynchronous uplink environments. The probability of error (POE) analysis for M-branch diversity system using alternate form of Q-function is derived and its performance is verified using SIC with maximal ratio combining (MRC) and minimum mean square error (MMSE) combining. The analysis of CC MC-CDMA systems under equal and unequal power variations is performed in asynchronous channel conditions and it was shown that considerable improvement in system capacity is achieved through multiuser detection.