Multicode CDMA transmission over time-varying multipath channels

To adapt to the adverse radio environment efficiently, we address the use of a pilot aided multicode code division multiple access (CDMA) system. This system is implemented by transmitting all the information symbols together with the pilot symbols of a user simultaneously over the wireless channel. We analyze the trade-off between the diversity order and the channel estimation error in the performance of the proposed system. Our numerical results indicate that depending on the transmitter power and the channel condition, the proposed system is capable of outperforming the conventional CDMA system with known channel state information at the receiver.