发明名称 |
Phase tracked loop frequency demodulator |
摘要 |
A phase tracked loop frequency demodulator having a phase comparator receptive of a frequency modulated signal and a peak-shifting filter for imparting a constant phase shift of 90 DEG over the full range of its instantaneous frequencies in response to a feedback control signal to permit the phase comparator to compare the non-phase shifted and phase shifted signals. The carrier frequency components of the output from the comparator are eliminated by means of a second filter to derive a demodulated signal which is used as the control signal. In order to eliminate high frequency limitations of the peak-shifting filter, this filter is comprised of a variable reactance element and a complementary reactance element so connected thereto to form a resonant circuit which possesses a quadratic frequency response characteristic with a resonant peak at the upper or lower frequency end of the passband.
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申请公布号 |
US4198609(A) |
申请公布日期 |
1980.04.15 |
申请号 |
US19780924554 |
申请日期 |
1978.07.14 |
申请人 |
VICTOR CO OF JAPAN LTD |
发明人 |
HAGIHARA, MASAKI;ISHIGAKI, YUKINOBU;KATO, KUNIHIRO;MURAOKA, TERUO;NASU, TAKEO |
分类号 |
H03D3/22;(IPC1-7):H03D3/22 |
主分类号 |
H03D3/22 |
代理机构 |
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主权项 |
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地址 |
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