An adaptive impedance matching system for mobile communication antennas

Abstract

An adaptive impedance matching system is proposed. This system employs only a simple algorithm for convergence, therefore does not need any complicated mathematical formulation for modeling the system itself and its nonlinear control elements. Also, the proposed system utilizes only simple digital circuits, for timing generation, and basic analog circuits. Even with a small range of capacitance for the control element in the matching circuit, there is an improvement in the mismatch by 2-3 dB over an impedance matching circuit with fixed capacitances.