Proposes one of the multiuser detection schemes, a new technique that has the potential to reduce interference or suppress multiple-access interference and, therefore, increase the capacity of optical code-division multiple access (CDMA) systems. It is a successive interference cancellation (SIC) scheme known as a low-complexity multiuser detection method for direct sequence CDMA systems. A SIC scheme is analyzed using an optical orthogonal code, with a different power for each user, that takes into account the impact of imperfect interference cancellation.