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:
Oct. 03, 2006
Filed:
Feb. 12, 2002
Satoshi Tanaka, Kokubunji, JP;
Masamichi Tanabe, Tokyo, JP;
Yasuyuki Okuma, Kokubunji, JP;
Taizo Yamawaki, Tokyo, JP;
Koichi Yahagi, Takasaki, JP;
Hiroaki Matsui, Takasaki, JP;
Robert Astle Henshaw, Cambridge, GB;
Satoshi Tanaka, Kokubunji, JP;
Masamichi Tanabe, Tokyo, JP;
Yasuyuki Okuma, Kokubunji, JP;
Taizo Yamawaki, Tokyo, JP;
Koichi Yahagi, Takasaki, JP;
Hiroaki Matsui, Takasaki, JP;
Robert Astle Henshaw, Cambridge, GB;
Renesas Technology Corp., Tokyo, JP;
Hitachi Device Engineering Co., Ltd., Nobara, JP;
TTPCom Limited, Royston Hertfordshire, GB;
Abstract
A transmitter is provided which includes a transmitting circuit that does not require a high-performance low noise VCO restricting cost reduction thereof and that can reduce the number of parts without requiring an RF filter. A direct conversion that does not require a transmission VCO is applied to the transmitting circuit. In order to achieve noise reduction in a receiving band, low-pass filters are provided a IQ input sections of a modulator that converts IQ signals into RF signals. In comparison with a conventional transmitter using offset PLL, an external VCO required in addition to an RF integrated circuit, a power amplifier, and a front end circuit is reduced. Even in current transistor performance, by using a filter having rapid waveform characteristics such as a SAW more inexpensive than the VCO, or the like, it is possible to provide a GSM/GSM 1800/GSM1900 triple band transmitter.