Hitachi, Ltd.

Space Communications Research Corporation

Haruhiko Funaki

Kenji Sekine

Masami Ohnishi

Yoichi Kaneko

Nobuo Masuda

Akio Iso

A high-frequency power amplifier comprises a pair of FETs, a divider which supplies opposite-phase versions of a signal to be amplified to the FETs, distributed-parameter transmission lines connected respectively at one ends thereof to output electrodes of the FETs, and a combiner which combines signals appearing at another ends of the transmission lines into a signal of a common phase. Stubs which short-circuit for even harmonics included in output signals of the FETs are connected respectively to the transmission lines at positions distant from the output electrodes of the FETs by a multiple of a quarter wavelength of the fundamental wave included in the output signals of the FETs. A first capacitor is connected between the transmission lines at positions distant from the output electrodes of the FETs by the 1/12 wavelength of the fundamental wave included in the output signals of the FETs so that the output electrodes of the FETs are open for the third harmonic, and a second capacitor is connected between the transmission lines at positions between the connecting positions of the first capacitor and the connecting positions of the stubs so as to perform impedance matching for the fundamental wave included in the output signals of the FETs.

High-frequency power amplifier

Disclosed is a microwave solid-state amplifier arranged such that a plurality of amplifier units are used in combination of a radial cavity resonator so as to perform power dividing/combining, and that in order to make the microwave solid-state amplifier capable of performing a wide band operation and have less circuit loss, a coupling portion between the radial cavity resonator and each of the amplifier units is formed such that a loop-like conductor constituted by a stripline forming an input/output portion of the amplifier unit is removably inserted through a slot formed in a side wall surface of the cavity resonator.

Microwave solid-state amplifier

Growing community of inventors

Tanashi, Japan

Haruhiko Funaki