Pulse or digital communications – Receivers – Interference or noise reduction
Reexamination Certificate
2007-12-18
2007-12-18
Fan, Chieh M. (Department: 2611)
Pulse or digital communications
Receivers
Interference or noise reduction
C375S354000
Reexamination Certificate
active
10833586
ABSTRACT:
A method and apparatus for the signal synchronization of an orthogonal frequency division multiplexing system includes a delay conjugate multiplication module, a phase processor and an edge detector. It provides estimates for the boundaries of inter-symbol interference free region by utilizing the characteristics of a guard interval in combination with the techniques of the delay conjugate multiplication module, phase differential operation, symbol-by-symbol average operation, and edge detection. The method determines a fixed optimal threshold for directly separating the inter-symbol interference region in a mobile environment to obtain an inter-symbol interference free version of symbol information.
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Chang Meng-Chun
Chang Yu-jung
Huang Chia-Chi
Sheu Chorng-Ren
Fan Chieh M.
Industrial Technology Research Institute
Joseph Jaison
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