发明名称 |
FREQUENCY GENERATION IN A WIRELESS COMMUNICATION UNIT |
摘要 |
A wireless communication device comprises a frequency generation circuit employing a crystal oscillator operably coupled to a fractional-based synthesiser and a voltage-controlled oscillator. The fractional-based synthesiser utilises a ratio between an integer value and a fractional value to set a radio frequency signal of the voltage-controlled oscillator. An automatic frequency control scaling sub-system is operably coupled to a fractional-based synthesiser and configured to receive and use an AFC word to frequency scale the fractional value in a multiplicative manner to set a radio frequency supported by the fractional-based synthesiser. Preferably, an automatic frequency generation sub-system utilises Absolute Radio Frequency Channel Number and the cyclical nature of the fractional value. In this manner, a saving on hardware and software overheads associated with frequency channel selection for fractional-N type synthesizers can be made.
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申请公布号 |
US2009117856(A1) |
申请公布日期 |
2009.05.07 |
申请号 |
US20040721656 |
申请日期 |
2004.12.15 |
申请人 |
FREESCALE SEMICONDUCTOR, INC. |
发明人 |
KELLEHER PAUL;O'KEEFFE CONNOR J. |
分类号 |
H04B1/40 |
主分类号 |
H04B1/40 |
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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