Patent
Automated method for determining total harmonic distortion
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TLDR
In this article, the accuracy of an automated THD measurement performed by an FFT signal analyzer is improved by refining the estimate of the signal's fundamental frequency on which the THD analysis is based.Abstract:
The accuracy of an automated THD measurement performed by an FFT signal analyzer is improved by refining the estimate of the signal's fundamental frequency on which the THD analysis is based. This refinement is accomplished by calculating a parameter that represents the relative accuracy of the estimate and then varying the estimate to maximize the parameter. The result is a process which permits refinement of the fundamental frequency to an almost arbitrary accuracy, resulting in a highly improved measurement of THD.read more
Citations
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References
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Patent
Fully digital spectrum analyzer using time compression and discrete fourier transform techniques
Joseph L Lehmann,Frank Lynch +1 more
TL;DR: In this article, a fully digital spectrum analyzer accepting as an input either an analog signal or a series of digital numbers is used to provide the spectral component values of the input signal.
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Real-time digital spectrum analyzer utilizing the fast fourier transform
TL;DR: In this paper, a digital signal processing system for computing the finite discrete Fourier transform coefficients from a number of digitized samples of an input signal in real-time is presented, where the signal being analyzed is sampled a predetermined number of times over a given interval, and this number of samples is expressed as the product of two integers, N r1. r2.
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Digital signal processing method for real-time processing of narrow band signals
Graham P. Bloy,William Ball +1 more
TL;DR: In this paper, a digital signal processing method for real-time processing of narrow band signals was proposed to provide for reconstitution of dynamic amplitude and harmonics beyond the passband.
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TL;DR: In this paper, the use of the State Variable (SV) circuit in both the oscillator and the filter sections confers several benefits and results in performance superior to previously available analyzers.
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Method for measuring a signal's frequency components
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