Space-time block coding applied to turbo coded multicarrier CDMA

In this article, we combine a Space-Time Block Code (STBC) with a Multi-Carrier Code Division Multiplex Access (MC-CDMA) system and a Turbo Code (TC) as channel code. MC-CDMA is likely to be one of the most promising access technique for future wireless communication systems [1][2]. In fact, MC-CDMA exploits the advantages of both the Orthogonal Frequency Division Multiplex (OFDM) multi-carrier modulation and of the Code Division Multiple Access (CDMA) technique. Moreover, the use of a Multiple Input Multiple Output (MIMO) OFDM system associated with a STBC code allows the achievement of both space and frequency diversities [6]. In this paper, we compare several STBC codes such as the Alamouti code [3] and the generalized codes for 3 or 4 antennas proposed by Tarokh [4] applied to a MC-CDMA system leading to different spectral efficiencies. Then, since Turbo Coded MC-CDMA was demonstrated to be very efficient for a Single Input Single Output (SISO) system, allowing the use of a simple Single User (SU) detector [2], we extend this system to Multiple Input Multiple Output (MIMO) systems for different STBC. Simulation results are provided for full load systems.