Back to results
US 5,631,933 AGranted
Phase-locked digital synthesizers
AssigneeHewlett-Packard Company
InventorsDavid C. Chu, Jeremy S. Sommer
Life of this patent
Estimating the term…
Abstract
A master and a slave digital frequency synthesizer are phase-locked such that the master synthesizer is always selected to minimize the phase hits which occur when switching the master to be a slave and vice versa. The switching rearrangement is done automatically and rapidly in the event of failure of the master frequency synthesizer.
Claims4
A system for synchronizing digital frequency synthesizers comprising:
- a first and a second synthesizer system, each system comprising:
- a local oscillator,
- a digital frequency synthesizer having an output, connecting to the local oscillator,
- a synthesizer modifier, connecting to the digital frequency synthesizer,
- a phase detector, connecting to the synthesizer modifier and the output of the digital frequency synthesizer, and
- the synthesizer modifier being operative to provide a tuning stimulus consistent with both a master and also a slave tracking a master;
- wherein the phase detector of the first synthesizer system is connected to the output of the digital frequency synthesizer of the second synthesizer system and the phase detector of the second synthesizer system is connected to the output of the digital frequency synthesizer of the first synthesizer system;
- a master/slave controller, connecting to the synthesizer modifiers of the first and the second synthesizer system;
- and
- a switch, connecting to the output of the digital frequency synthesizer of the first and the second synthesizer system.
7 more elements
Dependencies are inferred from the claim text.