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:
May. 29, 2007
Filed:
Jan. 08, 2004
Shunsuke Hirano, Yokohama, JP;
Yasunori Miyahara, Ayase, JP;
Shunsuke Hirano, Yokohama, JP;
Yasunori Miyahara, Ayase, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
The invention concerns a wideband modulator using a PLL synthesizer, which can match the frequency characteristic and prevent degradation in modulation accuracy even in the presence of a variation in the manufacture of circuit components. In a wideband modulator which modulates the division ratio of a frequency divider by using a modulating signal generated by a modulating signal generator and outputs a modulated carrier signal from a VCO, calibration data from a calibration data generator are input via a selector. The amplitude value of an ac component of each modulating signal, either appearing on the output of a loop filter or demodulated by a demodulator, is converted to a digital value by way of an A/D converter. The difference between the two is detected and a control signal FCR to eliminate the difference is generated in order to correct the frequency characteristic of a PLL or a pre-distortion filter.