发明名称 |
COHERENT DEMODULATION METHOD FOR A DIGITALLY MODULATED SIGNAL HAVING A CONTINUOUS PHASE AND A CONSTANT ENVELOPE |
摘要 |
The method ensures the coherent demodulation by digitally processing a continuous-phase modulated signal (for instance, of the GMSK type). The received signal is transposed in the baseband, converted into a digital signal and transferred to a signal processor. Each transmitted data packet has a known preamble sequence of N bits which allows for approximate estimation of the frame-synchronization and the bit-synchronization and also the initial phase and the residual frequency offset. The progressive refinement of the estimation is obtained with two interleaved digital loops: a slow loop for detecting the bit-synchronization and a fast loop effecting intermediate decisions over additional blocks of bits for the estimation of the initial phase and the residual frequency offset.
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申请公布号 |
US5151925(A) |
申请公布日期 |
1992.09.29 |
申请号 |
US19890370214 |
申请日期 |
1989.06.22 |
申请人 |
U.S. PHILIPS CORP. |
发明人 |
GELIN, BENOIT;LEBOURG, MICHEL |
分类号 |
H04L27/14;H04L27/00;H04L27/18;H04L27/233 |
主分类号 |
H04L27/14 |
代理机构 |
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代理人 |
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地址 |
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