Analysis of an up/down power control algorithm for the CDMA reverselink under fading

摘要

We analyze the performance of a code division multiple accessn(CDMA) reverse link a with an up/down power control algorithm in thenpresence of fading. We derive a stochastic nonlinear feedback controlnsystem model for the power controlled reverse link, and study the powerncontrol performance based on the nonlinear model using the technique ofnstatistical linearization. We provide a general analysis framework thatnallows us to study the effect of mobile speed, power control step size,nand fading channel parameters such as correlation coefficient and ratenof fading on power control errors. Numerical results show excellentnaccuracy of our analysis, which can be used to design and optimize thensystem parameters without going through lengthy simulations. Fornexample, in the presence of shadow fading, it is seen that a powerncontrol step size in the range of 0.5-1.3 dB is sufficient to keep powerncontrol errors near a minimum. In the case of Rayleigh fading, thenstandard deviation of power control errors grows quickly even atnmoderate mobile speeds