Electricity: measuring and testing – Particle precession resonance – Using a nuclear resonance spectrometer system
Patent
1993-08-11
1995-07-11
Arana, Louis
Electricity: measuring and testing
Particle precession resonance
Using a nuclear resonance spectrometer system
324307, G01V 300
Patent
active
054324475
ABSTRACT:
Disclosed is a phase unwrapping technique based on the solution of the Poisson equation. The problem of phase unwrapping in the continuous domain is formulated using an optimization approach where a cost functional is minimized. The minimizer is shown to be a solution of the Poisson equation with an appropriate boundary condition; the choice of the boundary condition depends on the particular application. The solution to the Poisson equation, i.e., the phase that minimizes the cost functional is referred to as the least squares phase. The least squares phase has thereby been unwrapped but, in general, will differ from the absolute phase due to noise. Using the least squares phase, the absolute phase is finally determined with an operator that maps the least squares phase to the absolute phase so that the computed absolute phase and the measured phase differ by multiples of 2.pi..
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Arana Louis
Board of Trustees of the Leland Stanford Junior University
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