Multiplex communications – Duplex – Communication over free space
Reexamination Certificate
2008-07-25
2010-12-07
Qureshi, Afsar M. (Department: 2472)
Multiplex communications
Duplex
Communication over free space
C455S076000, C455S260000, C716S030000, C327S105000
Reexamination Certificate
active
07848266
ABSTRACT:
Synthesizers are configured with first and second phase-locked loops (PLL's). The first PLL is arranged to include a digitally-controlled oscillator (DCO) and to respond to an input signal to provide a reference signal with a plurality of selectable reference frequencies. The second PLL is arranged to include a voltage-controlled oscillator (VCO) to thereby provide output signals in response to the reference signal. This synthesizer structure is particularly effective when responding to a noisy input signal as may be the case, for example, in wireless communication systems that provide a network clock to transceivers through lengthy optical links.
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Man Guanghua
Wang Yi
Analog Devices Inc.
Koppel, Patrick, Heybl & Dawson
Qureshi Afsar M.
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