Pulse or digital communications – Receivers – Automatic frequency control
Patent
1996-10-02
1998-06-16
Chin, Stephen
Pulse or digital communications
Receivers
Automatic frequency control
4551922, 375329, 375368, 375362, 370513, H04L 2706, H04L 2718, H04L 704
Patent
active
057683212
ABSTRACT:
An automatic frequency controller synchronizes a received carrier signal with a simulated carrier signal to automatically control a center frequency of the simulated carrier signal. The received carrier signal has a first synchronous code pattern inserted into a plurality of frame periods and a second synchronous code pattern inserted into a plurality of multiframe periods. The phase of the received carrier signal is determined by sweeping the center frequency of the simulated carrier signal and mixing the simulated carrier signal with the received carrier signal. The sweep of the center frequency of the simulated carrier signal is reduced when frame synchronization is detected and the sweep of the center frequency is fixed when multiframe synchronization is detected.
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Ono Mitsuhiro
Ueno Tomoyuki
Watanabe Hiroaki
Yamaguchi Seiichi
Chin Stephen
Deppe Betsy L.
Fujitsu Limited
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