ON A PARAMETRIC CONSTRAINED - TRANSMITTER POWER CONTROL SCHEME FOR CELLULAR RADIO SYSTEMS

Abstract

The capacity of cellular mobile radio systems can be increased by controlling the transmitter powers so as to control the carrier-to-interference ratios at the receivers. Since; power control is a real-time problem, to find the fastest carrier-to-interference ratio (CIR) balancing algorithm, which forces the CIR of each cell to converge to a value, has been the essential issue. Power control methods and their effectiveness in controlling carrier-to-interference ratio have been proposed by various authors. In this dissertation a novel parametric constrained power control algorithm is proposed. This power control scheme maintains the minimum necessary transmitted power for reliable communication and maintain a constraint on the maximum power. In this dissertation, a cellular structure of hexagonal shaped 20 cells and three channels are considered for both uplink and downlink simulation. Number of iterations required to reach 1-dB-range convergence and target CIR has been used as a measure for evaluating the performance of proposed power control algorithm and other power balancing strategies proposed by various authors. Distributed power control schemes are performed at each cell by using its current CIR measurements and the current transmitter power. Constrained power control schemes maximizes the minimum carrier-to-interference ratio, with a constraint on the maximum power. Parametric power control is performed at each base with some parameters provided by the central collector incorporating maximum power limit factor. The computation results show that the convergence of proposed CIR balancing algorithm is smooth and quick.