Title:
変調器及びその補正方法
Document Type and Number:
Japanese Patent JP4282998
Kind Code:
B2
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.
Inventors:
Shunsuke Hirano
Miyahara Yasunori
Miyahara Yasunori
Application Number:
JP2003002501A
Publication Date:
June 24, 2009
Filing Date:
January 08, 2003
Export Citation:
Assignee:
Panasonic Corporation
International Classes:
H03C1/00; H03C3/09; H03L7/093; H03L7/183; H03L7/197
Foreign References:
| WO2001093415A1 | ||||
| WO1999065146A1 |
Other References:
PERROTT M H ET AL,A 27-MW CMOS FRACTIONAL-N SYNTHESIZER USING DIGITAL COMPENSATION FOR 2.5-MB/S GFSK MODULATION,IEEE JOURNAL OF SOLID-STATE CIRCUITS,1997年12月,Vol.32,NO.12,p.2048-2060
Attorney, Agent or Firm:
Shohei Oguri
Kimihide Hashimoto
Toshimitsu Ichikawa
Kimihide Hashimoto
Toshimitsu Ichikawa