Improvement of DS-CDMA mobile communications systems by symbol splitting

A new technique to improve the bit error rate performance of CDMA (code-division multiple-access) mobile communications systems is proposed. The symbol duration for one information bit is divided into a few parts. These are transmitted with appropriate time spacing. The arrangement of the information stream is performed by an interleaver in the transmitter and a deinterleaver in the receiver. The achieved time diversity yields an improvement either of the bit error rate performance or the system capacity. Systems without channel coding and with convolutional encoding are considered. Simulation results demonstrate the improved performance of the new time diversity technique compared with conventional systems. This gain is achieved without affecting power, bandwidth, and data rate of the signal