An impedance-matching method for matching impedances of first and second circuits at two or more frequencies by using an impedance-matching circuit including reactance elements is provided, which makes it possible to set the impedance of two circuits to be connected at an optimum value or values at the...http://www.google.se/patents/US6329886?utm_source=gb-gplus-sharePatent US6329886 - Impedance-matching method and circuit at different frequences
