Patent ID: 7570131

Claim:
A dual-frequency matching circuit comprising: first and second input terminals that receive a first RF signal with a frequency of 0.85 GHz and a second RF signal with a frequency of 1.86 GHz, respectively, from an RF circuit with an impedance of 50 Ω; first and second output terminals that are connected to an antenna; and a group of circuit elements that are connected between the input terminals and the output terminals, wherein the group of circuit elements includes first and second, third and fourth elements, and wherein the first and fourth elements are connected in series between the first and second input terminals and the second and third elements are connected in series between the first and second input terminals, wherein the first output terminal is connected to a connection node between the first and fourth elements, and wherein the second output terminal is connected to a connection node between the second and third elements, and wherein the group of circuit elements is one of the two sets consisting of first and second ones, where the first set includes an inductor with an inductance of 12.084 nH, an inductor with an inductance of 5.452 nH, an inductor with an inductance of 14.508 nH, and a capacitor with a capacitance of 1.934 pF as the first, second, third and fourth elements, respectively, and the second set includes a capacitor with a capacitance of 1.023 pF, an inductor with an inductance of 5.772 nH, a capacitor with a capacitance of 0.904 pF, and an inductor with an inductance of 14.927 nH as the first, second, third and fourth elements, respectively.