发明授权
EP0962046B1 SYSTEM AND METHOD FOR HARMONIC INTERFERENCE AVOIDANCE IN CARRIER RECOVERY FOR DIGITAL DEMODULATION
失效
系统和方法,便于向承运人RUCK集合数字解调慢干扰
- 专利标题: SYSTEM AND METHOD FOR HARMONIC INTERFERENCE AVOIDANCE IN CARRIER RECOVERY FOR DIGITAL DEMODULATION
- 专利标题(中): 系统和方法,便于向承运人RUCK集合数字解调慢干扰
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申请号: EP98903523.3申请日: 1998-01-15
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公开(公告)号: EP0962046B1公开(公告)日: 2003-04-02
- 发明人: COMAN, Ion , HANNA, Kenneth, M.
- 申请人: Scientific-Atlanta, Inc.
- 申请人地址: 5030 Sugarloaf Parkway Lawrenceville, GA 30044 US
- 专利权人: Scientific-Atlanta, Inc.
- 当前专利权人: Scientific-Atlanta, Inc.
- 当前专利权人地址: 5030 Sugarloaf Parkway Lawrenceville, GA 30044 US
- 代理机构: Kügele, Bernhard
- 优先权: US36769P 19970131
- 国际公布: WO98035544 19980820
- 主分类号: H03D7/16
- IPC分类号: H03D7/16 ; H03J7/02
摘要:
The present invention relates to an improved demodulator for locking onto and tracking a carrier. Harmonic frequencies are occasionally generated by demodulation circuitry. When this occurs, the harmonic frequencies can interfere with the demodulator's locking and tracking functions, especially if the harmonic frequencies are near a down converted carrier's frequency. A system and method are disclosed which provides an offset to a frequency synthesizer (107) whose output frequency (F1, F2) is used to down convert (104) the carrier. The offset alters the frequency of the down converted carrier so as to shift it away from the interfering harmonics. In this regard, the demodulator is enabled to lock onto and track a carrier when previously not possible.
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