SIR-based power control in a CDMA system

Power control in the use of direct-sequence code-division multiple-access (CDMA) techniques is addressed. Previous performance analyses of CDMA wireless mobile and personal communications have assumed the ability of power control to equalize the absolute signal powers of users received at each base station. A more practical, although analytically more complicated, uplink power controls technique that uses measurements of the received signal-to-interference ratio. (SIR) instead is studied. A combination of discrete-event link simulation and analysis of the obtained SIR statistics is used to explore the behavior of a CDMA system using SIR-based power control and to obtain performance estimates for such a system under various operating assumptions. The overall results indicate that power control based on SIR has the potential for somewhat higher system performance than power control based on absolute signal strength