Pulse or digital communications – Synchronizers
Reexamination Certificate
2007-05-29
2007-05-29
Bocure, Tesfaldet (Department: 2611)
Pulse or digital communications
Synchronizers
C375S247000, C327S277000
Reexamination Certificate
active
10387330
ABSTRACT:
A delta-sigma modulator that provides improved SNR performance in applications such as low-power mobile wireless communications and high frequency radar applications is disclosed. Multiple comparators10, each comprising a sequence of three latches20, 22, 24, connect the modulator's input filter circuit12to the modulator's output interfaces14, providing quantization of the integrated, filtered signal provided by the filter circuit12. A clock signal having a cycle period Tcenables a first latch20connected to the signal input of each comparator10to provide a digital signal to the signal input of a second latch22. The second latch22supplies a digital signal to a third latch24in the sequence, in response to the signal received from the first latch20, by a lagged clock signal derived from the given clock signal Tcby providing a first lag time TLwhere Tc/2≧TL>0. A third latch in the sequence is enabled by a clock signal having a second lag time TS=Tc/2+TE, and the delay TE<<Tc/2. When TL=Tc/2 the inverted clock signal supplied to the second latch is delayed and supplied to the third latch. When TL=TEthe delayed clock signal supplied to the second latch is inverted and supplied to the third latch.
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Bocure Tesfaldet
HRL Laboratories LLC
Ladas & Parry LLP
Panwalkar Vineeta
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