High speed wireless turbo-coded OFCDM systems
Orthogonal frequency and code division multiplexing (OFCDM) systems have been introduced for high speed data transmission in future wireless mobile communications. In this paper, a hybrid multicode interference cancellation (MCI) and minimum mean square error (MMSE) detection scheme is presented for the turbo-coded OFCDM systems. Channel estimation based on a code-multiplexed pilot channel is employed. The weights of hybrid detection are derived and an effective method is proposed to estimate the weights in practical applications. By means of computer simulation, the system performance is studied to show how it is affected by parameters such as modulation schemes, the number of stages of the hybrid detection, the power ratio of pilot to data channels, spreading factor, and so on.