A sigmoid-basis nonlinear power control algorithm for mobile radio systems

The convergence speed and distributiveness are important properties of a power control algorithm to determine its potential for practical usage in cellular radio systems. Most of the power control algorithms in the literature are derived from numerical linear algebra or linear control theory, and consequently are in linear form. This paper, on the other hand, proposes a (sigmoid-basis) nonlinear power control algorithm, which is fully distributed and first order. The algorithm is obtained by discretization of the differential equation form of the algorithm shown to be stable in the case of a feasible system. We carried out computational experiments on a CDMA system. The results indicate that our algorithm significantly enhances the convergence speed of power control in comparison with linear distributed power control algorithm of Foschini and Miljanic (1993) as a reference algorithm.