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

Abstract

PO BOX 5400, FIN-02015 HUT, FINLAND. AbstractConvergence speed and distributiveness are important properties of a power control algorithm to determine its potentialforpractical usage in cellular radio systems. Most of the power control algorithms in 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 ordel: The algorithm is obtained by discretization of the direrential equation form of the algorithm shown to be stable in the case of feasible system. We cam'ed 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 Miuanic CIS a reference algorithm.

Power Allocation in Multirate DS/CDMA Systems Based on Verhulst Equilibrium

“…In all of the simulations the entries values for the QoS targets were fixed in δ * = 4 dB, the adopted receiver noise power for all users is P n = −63 dBm, and the gain matrix G have intermediate values between those used in [10] and [8].…”

“…1, for power allocation solution (inferior plots). Plateaux indicate convergence to the optimum power vector, p * ; hence dot lines (P opt in legend) indicates analytical solution given by (10). Note the fast convergence for all users when α = 0.9, i.e., N ≈ 25 iterations, against ≈ 150 for α = 0.1.…”

“…This property makes that the algorithm sensitivity to estimation errors is independent of the real value of SINR. It is known that a function like ϕ = κδ −1 (SINR in the denominator is inherent to all known DPCAs proposed in the literature, as the classical [3] and sigmoidal [10]) has a differential increment dϕ = −κδ −2 dδ i.e., the amount of ϕ variation for small δ deviations depends on the real value of the SNIR, δ. For a function like ϕ = κδ as in (12), we have dϕ = κdδ, which is in fact independent of the real value of δ.…”

Distributed nonlinear power control in cellular mobile networks with each user communicating with several base stations

“…This problem has attracted a lot of attention; see e.g. [1], [2], [3] and references therein. Several efficient distributed power control algorithms converging to a fixed point were proposed.…”

Power-Rate Allocation in DS/CDMA Systems Based on Discretized Verhulst Equilibrium

“…canal possui valores intermediários entre aqueles utilizados em[8] e[6]. Os valores adotados para perda de percurso, sombreamento, desvanecimento Rice e máxima frequência Doppler estão indicados na seção Ganhos de Canal da Tabela I.…”