Performance of SIR based power control in the presence of non-uniform traffic distribution

This paper investigates a reverse-link transmit power control scheme based on received signal-to-interference power ratio (SIR) measurements in a direct sequence code division multiple access (DS-CDMA) cellular system with non-uniform traffic distribution. The statistics of the received SIR at the cell site and the reverse-link transmitter power are evaluated by computer simulations. A maximal ratio combining (MRC) diversity hand-over (DHO) scheme is considered. As the transmit power of the portable station is adaptively controlled, the quality of each user's reverse-link channel can be maintained with reduced transmit power. It is confirmed that SIR-based power control can significantly reduce the transmit power of portable stations even under non-uniform traffic distributions and a further reduction is achieved by using MRC-DHO.