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Hamidreza Jamalabadi1,2,3, Tahmineh A Koosha1, Elina Stocker1

  • 1Department of Psychiatry and Psychotherapy, https://ror.org/01rdrb571Marburg University, Marburg, Germany.

Psychological medicine
|November 25, 2025
PubMed
概括

生态瞬间评估 (EMA) 需要最佳的采样率. 每周或每两周一次的症状测量足以进行定期监测,根据尼奎斯特-香农定理.

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Determination of Expected Frequency

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Classification of Signals

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Reconstruction of Signal using Interpolation

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Aliasing01:18

Aliasing

Accurate signal sampling and reconstruction are crucial in various signal-processing applications. A time-domain signal's spectrum can be revealed using its Fourier transform. When this signal is sampled at a specific frequency, it results in multiple scaled replicas of the original spectrum in the frequency domain. The spacing of these replicas is determined by the sampling frequency.
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Upsampling01:22

Upsampling

Managing signal sampling rates is essential in digital signal processing to maintain signal integrity. A decimated signal, characterized by a reduced frequency range due to its lower sampling rate, can be upsampled by inserting zeros between each sample. This upsampling process expands the original spectrum and introduces repeated spectral replicas at intervals dictated by the new Nyquist frequency. To refine this zero-inserted sequence, it is passed through a lowpass filter with a cutoff...
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Frequency-Domain Interpretation of PD Control01:24

Frequency-Domain Interpretation of PD Control

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