Multiuser Transmission in Conjunction with Smart Antennas for the Downlink of TDD-CDMA System

The multiuser transmission (MUT) is an effective way to eliminate the multiple-access interference (MAI) and the inter symbol interference (ISI) in the downlink channel of TDD-CDMA. In this paper, a novel MUT model is developed. In the model, the MUT combined with smart antennas (SA) is taken to improve the performance of TDD-CDMA in the spatial-temporal channel. Two different MUT algorithms in conjunction with the beamforming algorithm of SA are researched and the simulation results illustrate that the new MUT model achieves the better performance than the MUT model without SA