Performance of block spreading MIMO-CDMA systems for heavy multi-path environment

In CDMA systems using block spreading techniques, where a data-block modulates a spreading sequence to produce a transmitting symbol, a user inherent orthogonal carrier-frequency modulating system is proposed. This method contributes to accommodating as many users as the processing gain L and to reducing the guard sequence overhead. Applying a MIMO configuration without using coding and multiple constellation on PSK modulation to this system, especially using N pieces of receive antennas is considered. This block spreading system is capable of accommodating as many users per orthogonal carrier as N, by using a method of concatenating the N symbols received at N antennas. This means that the aggregate data rate per chip increases N in the maximum. Further it is shown that a fairly good error rate performance is achieved by selecting the practical aggregate data rate to be about 80% of the maximum rate.