Multiple antenna options for high data rate CDMA systems

1xEV-DO (1xEVolution-Data Only) is a method for transmission of wireless packet data at high rates which is based on code division multiple access (CDMA) technology. Adaptive modulation and coding is used together with proportional fairness scheduling to take full advantage of the channels between the base stations and mobile stations when they are at their best. Methods such as receive antenna diversity and multiple input multiple output (MIMO) have the potential to improve the performance of such a system. A model which simulates an 1xEV-DO network with multiple transmit and receive antennas has been developed to investigate this. Results are given showing how the throughput varies with the number of users per cell for different numbers of transmit and receive antennas. The performance of MMSE (minimum mean square error) and MRC (maximal ratio combining) algorithms are also investigated. The effects of introducing multiple paths and Rayleigh and Rician fading are compared. Simulation results for multiple transmit and receive antennas are compared with the channel capacity predicted by the Shannon capacity equation.