发明名称 |
FM Modulator using an oscillating feedback circuit |
摘要 |
A frequency modulating circuit for modulating a carrier signal by a modulating signal is disclosed which includes a band-pass filter of biquad type having a first integrating circuit and a second integrating circuit, an output of the first integrating circuit being supplied to an input terminal of the second integrating circuit and an output of the second integrating circuit being supplied to an input terminal of the first integrating circuit and a second input terminal of the second integrating circuit, and a limiting amplifier circuit supplied with the output signal of the band-pass filter and the output thereof being positively fed back to the band-pass filter. In this case, the modulating signal is supplied to the first and second integrating circuits such that the center frequency of the band-pass filter is linearly controlled by the modulating signal whereby a frequency modulated signal modulated by the modulating signal is led out of the output terminal of the second integrating circuit.
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申请公布号 |
US4568892(A) |
申请公布日期 |
1986.02.04 |
申请号 |
US19840591979 |
申请日期 |
1984.03.21 |
申请人 |
SONY CORPORATION |
发明人 |
EMORI, TAKAHISA;KIKUCHI, MASAFUMI |
分类号 |
H04N5/922;G11B20/06;H03C3/00;H04N5/92;(IPC1-7):H03C3/02 |
主分类号 |
H04N5/922 |
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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