发明名称 |
Decision feedback demodulator with phase and frequency estimation |
摘要 |
A data communication receiver (10) uses a decision feedback demodulator (32) to remove data from a received signal. Quadrature components of the received signal define a received phase. The received phase is rotated (46) by an amount predicted to compensate for phase and frequency errors. After this rotation, a decision circuit (52) determines the modulation phase for a current symbol. A phase rotator (64) compares the modulation phase with the received phase to generate a measured phase error for the symbol. This measured phase error and measured phase errors from past symbols are averaged in a combination circuit (80) to produce a phase estimate. The past measured phase errors are also processed to determine the amount of change in measured phase error that has occurred over a number of symbols. This processing yields a frequency estimate. A phase rotator (94) merges the frequency and phase estimates for use in compensating a current received phase.
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申请公布号 |
US5497400(A) |
申请公布日期 |
1996.03.05 |
申请号 |
US19930161845 |
申请日期 |
1993.12.06 |
申请人 |
MOTOROLA, INC. |
发明人 |
CARSON, LANSING M.;BURDGE, ROBERT J. |
分类号 |
H04L27/227;(IPC1-7):H04L27/14;H04L27/16;H04L27/22 |
主分类号 |
H04L27/227 |
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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