Pulse or digital communications – Synchronizers – Frequency or phase control using synchronizing signal
Reexamination Certificate
2006-02-28
2006-02-28
Tran, Khanh (Department: 2631)
Pulse or digital communications
Synchronizers
Frequency or phase control using synchronizing signal
C375S363000, C370S509000
Reexamination Certificate
active
07006587
ABSTRACT:
The repetitive structure of a preamble signal is exploited to enhance timing synchronization performance and frame start detection performance under adverse channel conditions. Received values are cross-correlated in time against a known noise-free version of the preamble. The presence of peaks in the cross-correlation output indicates presence of a frame. The peak locations provide symbol timing. Further cross-correlation processing and/or non-linear processing can be used to enhance the signal to noise ratio of the peaks.
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Lewis Michael
Theobold David M.
Cisco Technolgy, Inc.
Inventek
Lang Dan
Rosenfeld Dov
Tran Khanh
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