Multi-user space-time diversity system design for uplink multi-carrier CDMA

In this paper, we propose a multi-user detector for space-time uplink transmission in multi-carrier CDMA systems. We propose a new combination using STBC, OFDM and CDMA spreading. The OFDM codewords are built from chips issued from different symbols. The STBC encoding is done at the last stage of the transmitter and we place STBC decoder after multi-user mitigation. We show that our system is particularly easy to implement while obtaining similar performance compared to a single user STBC system.