Power control and rate allocation in multirate wideband CDMA systems

Abstract

As a multiple access technology, DS-CDMA operates in an interference limited environment so the system capacity is dominated by multiple access interference (MAI). Since MAI is proportional to the transmit power strengths of other users, the level of transmit power by all participating users requires careful planning and control in order to attain maximum system capacity. The power distribution under a multirate wideband CDMA environment is investigated. It is shown that power control is a function of the spread bandwidth, user data rates, and the user QoS requirements. A power control algorithm, based on a convergence criterion, is proposed. Numerical results which demonstrate the viability of the power control algorithm are presented.