Rake combining effect on link capacity and peak transmit power of power-controlled reverse link of DS-CDMA cellular mobile radio

For the power controlled DS-CDMA reverse link, two important issues must be addressed when using a Rake combiner with a limited path diversity order (defined as the number of resolved paths used for combining): the decrease in link capacity and the increase in peak transmit power. The peak transmit power is an important design parameter of transmit power amplifiers. In this paper, expressions for the achievable capacity and required peak transmit power under a multi-cell environment are developed. Based on the developed expressions, the relative capacity and required peak transmit power are evaluated theoretically and by Monte Carlo simulations under multipath Rayleigh fading environments with uniform and exponential power delay profiles. The effects of Rake based on maximal ratio combining (MRC) and selection combining (SC) are compared. The influence of the power delay profile shapes is also discussed.