发明名称 |
Demodulator using cordic rotator-based digital phase locked loop for carrier frequency correction |
摘要 |
A digital data demodulator employs a cordic rotator-based, digital phase locked loop for carrier frequency tracking. Digitized I and Q channels downconverted to baseband using a fixed frequency oscillator are coupled to a digital cordic rotator. The cordic rotator iteratively executes pipelined phase-rotational adjustments of its digitized in-phase and quadrature inputs, in association with a pipelined reduction of the accumulated value of a phase angle vector code generated by digital phase error detection logic circuitry to which rotated I and Q outputs of the cordic rotator are applied. The phase error representative code vector is coupled through a digital loop filter as a reference angle input to the cordic rotator. The cordic rotator iteratively rotates the I and Q channel values that reduce the accumulated phase error to zero.
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申请公布号 |
US2004208263(A1) |
申请公布日期 |
2004.10.21 |
申请号 |
US20040839533 |
申请日期 |
2004.05.05 |
申请人 |
ADTRAN, INC. |
发明人 |
RIVES ERIC M.;GANN MATTHEW F.;GOODLOE ANTHONY A. |
分类号 |
H04L27/00;H04L27/233;(IPC1-7):H04L27/06;H03D1/00;H03D3/18 |
主分类号 |
H04L27/00 |
代理机构 |
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主权项 |
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地址 |
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