发明名称 |
Bit clock signal generator for use in a digital signal demodulator |
摘要 |
This invention relates to a digital audio tape recorder using a rotary magnetic head. On the tape which has been recorded using R-DAT, signals forming to the industry standards are recorded at a standard tape speed. The tape is caused to run at a speed faster than the standard tape speed and the recording signal is subjected to high speed reproducing while maintaining the rotational frequency of the head at a rotational speed at the time of recording. For realizing this, a bit clock signal generator for use in a digital signal demodulator is provided, which comprises means for generating a detection window pulse having a predetermined pulse width shorter than a period of a bit clock signal from either of time points of rise and fall of the waveform of a signal to be demodulated, or from both the time points thereof, said signal to be demodulated being a digital signal modulated in accordance with a modulation system such as a system constituted with a periodical signal intermittently including a phase information of the bit clock signal to deliver the detection window pulse to a phase locked loop including a phase comparison circuit and a voltage controlled oscillator as a comparison wave, thus allowing the voltage controlled oscillator in the phase locked loop to generate a bit clock signal, characterized by the provision of means for changing the pulse width of the detection window pulse in correspondence with changes in a bit rate of the demodulated signal.
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申请公布号 |
US4777452(A) |
申请公布日期 |
1988.10.11 |
申请号 |
US19870102997 |
申请日期 |
1987.09.30 |
申请人 |
VICTOR COMPANY OF JAPAN LTD. |
发明人 |
HAYAMI, ATSUSHI;ONO, TSUYOSHI;HIKAWA, KAZUO;SHIMIZU, TAKESHI |
分类号 |
H03K5/00;G11B20/10;G11B20/14;H04L7/027;H04L25/40;(IPC1-7):H04B1/16 |
主分类号 |
H03K5/00 |
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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