发明名称 |
Digital FM demodulator using delayed signal product with arctangent |
摘要 |
FM signals are demodulated with lower distortion and expenditure of less computing time by digitizing the signals using an A/D converter of predetermined sample frequency and down-converting the signals to their base band quadrature components. The quadrature components are delayed by one sample period, and the complex cross-product of current quadrature components and the delayed quadrature components from the immediately preceding A/D sample period is taken. The arctangent of the resulting cross-product is taken by calculating the ratio of the imaginary and real components thereof to produce a value which is representative of the original modulating signal.
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申请公布号 |
US4750214(A) |
申请公布日期 |
1988.06.07 |
申请号 |
US19860873242 |
申请日期 |
1986.06.11 |
申请人 |
ROCKWELL INTERNATIONAL CORPORATION |
发明人 |
HART, BILLY D.;PETERSON, JR., MAURICE W. |
分类号 |
H03D3/00;H03D3/22;H03D7/16;(IPC1-7):H04B1/16 |
主分类号 |
H03D3/00 |
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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