The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 18, 2003
Filed:
Feb. 28, 2002
Toru Fujioka, Kokubunji, JP;
Isao Yoshida, Nishitama, JP;
Mineo Katsueda, Hachioji, JP;
Masatoshi Morikawa, Saitama, JP;
Yoshikuni Matsunaga, Hachioji, JP;
Kenji Sekine, Nishitama, JP;
Osamu Kagaya, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A radio frequency power amplifier module for a dual-band type mobile communication apparatus that can transmit and receive a first frequency f and second frequency f (f f ). It includes a drive stage amplifier having the gain peaks at f and f with a matching circuit and a radio frequency power output circuit including a radio frequency power output transistor. The output circuit has a transmission line connected to the drain end of the output transistor, a parallel resonance circuit connected in series to the transmission line to resonate at harmonics of a frequency twice the frequency f , a series resonance circuit provided between one end of the resonance circuit and the ground to resonate at harmonics of a frequency twice the frequency f and an output matching circuit provided in series to the other end of the parallel resonance circuit for matching with f and f