发明名称 |
Method and apparatus to perform digital demodulation by measuring periods between zero crossings |
摘要 |
A digital demodulator provides efficient demodulation of frequency modulated, pulse-width modulated, and other temporally modulated signals. Without employing an analog-to-digital converter, modulating signal information is extracted from a modulated signal as numerical information. For frequency demodulation, a high gain stage is applied to an incoming FM signal to produce a corresponding sequence of square waves. The period between zero-crossings of the square waves is accurately measured to within one clock pulse using a high-speed clock and at least one counter to produce a demodulated signal.
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申请公布号 |
US5272448(A) |
申请公布日期 |
1993.12.21 |
申请号 |
US19920875848 |
申请日期 |
1992.04.29 |
申请人 |
NUMA TECHNOLOGIES, INC. |
发明人 |
HEDSTROM, MARK D.;PORTER, ROBERT B.;CREGO, CHARLES R. |
分类号 |
H03D3/04;H03K9/06;H03K9/08;(IPC1-7):H03D3/00 |
主分类号 |
H03D3/04 |
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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