发明名称 |
Modulator and correction method thereof |
摘要 |
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.
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申请公布号 |
US7224237(B2) |
申请公布日期 |
2007.05.29 |
申请号 |
US20050531050 |
申请日期 |
2005.04.12 |
申请人 |
MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD. |
发明人 |
HIRANO SHUNSUKE;MIYAHARA YASUNORI |
分类号 |
H03C1/00;H03C3/00;H03C3/09;H03L7/06;H03L7/093;H03L7/183;H03L7/197 |
主分类号 |
H03C1/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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