BER analysis of a modified space-time spreading code for CDMA systems in MIMO Ricean channels

In this paper, we derive an analytical bit-error-rate (BER) formula for evaluating the system performance of MSTS (modified space-time spreading) code with space-time diversity for cellular CDMA systems. The BER analysis for the MSTS is carried out for a multiple transmit and receive antenna system (also known as a MIMO system) in Ricean channels. For MIMO Ricean channels, the analytical BER is derived as function of angle spread, Doppler spread, and the Ricean K-factor. The BER results show that MSTS exploits spatial diversity and temporal diversity in time-varying MIMO channels and is compared to existing STS (space-time spreading) scheme. The results also show that the MSTS outperforms STS in a high mobility cellular environment.