Co-authors: R. Jäntti and H. N. Koivo
Along with "distributiveness" convergence speed of power control is one of
the most important criteria by which we can determine the practical applicability of a
given power control algorithm. A good power control algorithm should quickly and
distributively converge to the state where the system supports as many users as possible.
This paper proposes a fast and distributed power control algorithm based on the well-known
PI-controller. As in the paper by Foschini and Miljanic, we start with differential
equation form of the controller and analyze its convergence properties in the case of
feasible systems. The actual power control algorithm is then derived by discretization of
the continuous time version. Using the distributed constrained power control (DCPC) as a
reference algorithm, we carried out computational experiments on a CDMA system. The
results indicate that our algorithm significantly enhances the convergence speed of power
control.
Co-author: H. N. Koivo
Most of the power control algorithms in literature have roots in numerical linear algebra or linear control theory, and consequently are in linear form. This paper proposes a first order, fully distributed and sigmoid-basis nonlinear power control algorithm. The advantage of using nonlinearity is in fast convergence and robustness against Rayleigh fading. In comparison with linear distributed power control algorithm of Foschini and Miljanic as a reference algorithm, convergence speed is improved. Simple computer simulations have verified the effectiveness of the proposed algorithm.
[1] Z. Uykan, C. Guzelis, E. Celebi and H. N. Koivo, "Analysis of Input-Output Clustering for Determining Centers of RBFNs", IEEE Trans. on Neural Networks, in press. (Related non-RAVE publication.)
[2] Z. Uykan and H. N. Koivo, "Upperbounds on RBFN designed by Input Clustering", IEEE-ACC (American Control Conference) 2000, Chicago, USA, June, 2000, in press. (Related non-RAVE publication.)
[3] Z. Uykan and H. N. Koivo, "Unsupervised learning of sigmoid perceptron", IEEE-ICASSP2000 (International Conference on Acoustics, Speech, and Signal Processing), Istanbul, Turkey, June 5-9, 2000, in press. (Related non-RAVE publication.)
[4] Z. Uykan, K. Zenger and H.N. Koivo, "Sliding Mode Control for DC/DC Buck Converter in Voltage Mode", IPEC (International Power Electronics Conference)-2000, Tokyo, Japan, April 3-7, 2000, in press. (Related non-RAVE publication.)
[6] Z. Uykan and H. N. Koivo, "A Sigmoid-Basis Nonlinear Power Control Algorithm for Mobile Radio Systems", submitted to IEEE-VTC2000 (Vehicular Technology Conference), Boston, USA, 2000.