Amplifier circuit having impedance matching circuit
AssigneeNEC Corporation
InventorKazuhiko Honjo
Life of this patent
Estimating the term…
Abstract
An amplifier circuit having an impedance matching circuit coupled between a transistor having an element impedance of Z.sub.Tr and a first transmission line having a characteristic impedance of Z.sub.0, the impedance matching circuit including a second transmission line having a characteristic impedance Z.sub.T0 .apprxeq.(Z.sub.Tr .times.Z.sub.0).sup.1/2 and a length of a quarter wavelength, and a high-harmonic processing circuit disposed at the connection of the second transmission line to the first transmission line. The high-harmonic component processing circuit has two parallel stubs each having a certain characteristic impedance and a released tip end, the two parallel stubs having length of one-eighth wavelength and one-twelfth wavelength, respectively.
Claims4
An amplifier circuit having an impedance matching circuit coupled between a transistor having an element impedance of Z.sub.Tr and a first transmission line having a characteristic impedance of Z.sub.0, said impedance matching circuit comprising:
- a second transmission line disposed between a terminal of said transistor and said first transmission line, said second transmission line having a characteristic impedance of Z.sub.T0 .apprxeq.(Z.sub.Tr .times.Z.sub.0).sup.1/2 and a length of a quarter wavelength;
- and
- a higher harmonic processing circuit disposed at the connection of said second transmission line to said first transmission line, said higher harmonic processing circuit having two parallel stubs each having a certain characteristic impedance and an open tip end, said two parallel stubs having length of a one-eighth wavelength and a one-twelfth wavelength, respectively.
An amplifier circuit having an impedance matching circuit coupled between a transistor having an element impedance of Z.sub.Tr and a first transmission line having a characteristic impedance of Z.sub.0, said impedance matching circuit comprising:
- a second transmission line disposed between a terminal of said transistor and said first transmission line, said second transmission line having a characteristic impedance of Z.sub.T0 .apprxeq.(Z.sub.Tr .times.Z.sub.0).sup.1/2 and a length of a quarter wavelength;
- and
- a higher harmonic processing circuit disposed at the connection of said second transmission line to said first transmission line, said higher harmonic processing circuit having N parallel stubs each having an open tip end, each of said parallel stubs having a length L defined by a following equation:
- L=.lambda./4(1+m)
- wherein .lambda. represents a wavelength, and m represents an integer ranging from one (1) to N.
Dependencies are inferred from the claim text.