TDD-CDMA capacity loss due to adjacent channel interference in the macro environment employing smart antenna techniques

The smart antenna scheme, as one of key techniques of TDD-CDMA, increases the capacity of a system, enlarges the coverage range of a cell, and improves the quality of the signal. In this paper, the capacity increase by adopting a smart antenna is investigated. The capacity loss due to adjacent channel interference in macro environments is presented when an omni-directional or smart antenna is adopted. Simulations were carried out to investigate the relations between the capacity and ACIR, the different frame synchronization offset, the distance offset and cell radius of the node Bs in two TDD-CDMA operators. The difference in impacting capacity loss between omni-directional and smart antennas is analyzed and compared. Results and conclusions are shown, which are useful for future cellular planning.