Performance analysis of a mobile system based on combined SDMA/CDMA access technique

The space division multiple access (SDMA) technique allows one to increase the capacity of a mobile cellular system, exploiting the users spatial separation. This technique can be integrated with different multiple access techniques, such as FDMA, TDMA and CDMA: therefore it can be used in all the mobile systems currently operated or to be introduced in the future. The SDMA technique is reviewed and the possibility of its introduction in a CDMA mobile system is analysed. In particular, the capacity increase obtainable with a combined SDMA/CDMA access technique is evaluated by means of computer simulation.