发明名称 |
Quadrature modulation compensation |
摘要 |
The present invention is related to methods and apparatus that compensate for quadrature impairments of an analog quadrature modulator and/or demodulator over a relatively wide signal bandwidth. One embodiment pre-distorts baseband signals in a quadrature modulator compensation signal processor (QMCSP) to negate the quadrature impairment of an analog quadrature modulator and corrects a received baseband signal in a quadrature demodulator compensation signal processor (QDCSP) to cancel the quadrature impairment of an analog quadrature demodulator. The QMCSP and the QDCSP contain adaptive digital filter correction structures that pre-compensate and post-compensate, respectively, for the quadrature impairments introduced by the analog quadrature modulator and the analog quadrature demodulator over a relatively wide bandwidth. A phase shifter advantageously shifts the phase of a local oscillator signal to the analog quadrature demodulator to distinguish quadrature impairments introduced by the modulation path from quadrature impairments introduced by the demodulation path.
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申请公布号 |
US7515650(B1) |
申请公布日期 |
2009.04.07 |
申请号 |
US20050099098 |
申请日期 |
2005.04.05 |
申请人 |
PMC-SIERRA, INC. |
发明人 |
WARNER WILLIAM DEAN;SHIN SOON SUN;WRIGHT ANDREW S. |
分类号 |
H03C3/00;H03C3/40;H03D3/00;H03K7/06;H04L5/12;H04L23/02;H04L27/00;H04L27/12 |
主分类号 |
H03C3/00 |
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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