Design of an automatic impedance-matching device

An automatic impedance-matching device using a sectioned transmission line attached with many switching reactive elements is described. The device can give a good impedance matching for a load with an arbitrary impedance Afte r the load impedance is determined by measuring the voltage amplitudes at t he junction points of the matching line, the switching states of the reacti ve elements (switch off; or switch to a capacitance or an inductance) are d etermined by either a noniterative method or a genetic algorithm. (C) 1999 John Wiley & Sons, Inc.