Capacity estimation for an SIR-based power-controlled CDMA system supporting ON-OFF traffic

Capacity estimation in code division multiple access (CDMA) systems is an important issue which is closely related to power control. Many previous studies assumed strength-based power control, which maintains received power at a desired level regardless of changes in the number of active users and in the amount of total other cell interference. However, in signal-to-interference ratio (SIR)-based power control systems, which maintain the received SIR at a desired level, the power level is a function of the above two variables. This study derives the reverse link capacity of an SIR-based power control system supporting ON-OFF traffic in a multiple cell environment. Two different power control systems are compared in terms of capacity in both CBR and ON-OFF traffic environments. The effects of activity factor, the required E_b/I_o, the maximum received power, and propagation parameters are also investigated.