# Questions tagged [nyquist]

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### Nyquist rate determination and oversampling [duplicate]

I'm new to this. I'm using ShannonGui to generate a sine wave with a $1\textrm{ Hz}$ signal frequency. From what I can tell to determine the Nyquist rate I need to double the highest frequency, since ...
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### what is difference between Alias vs. down sampling? [closed]

could someone help me explain downsampling in the context of Nyquist–Shannon sampling theorem and tell the difference between Aliasing and downsampling.Also is downsampling and undersampling the same ?...
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### Does sampling ~> Nyquist frequency capture harmonics?

In a debate on the value of 24b/192KHz consumer audio (using a good brick wall filter, minimal jitter), a friend posed the argument: Nyquist never properly dealt with harmonics, which change sound ...
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### Why do we follow Shannon's Theorem in audio sampling?

My professor told me that in sampling a signal, is not usual to respect the Shannon theorem because the interpolation formula contains sines and fractions which are difficult to calculate with a ...
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### How do I apply the Nyquist criterion on the following spectrum to see if it satisfies the criterion or not?

I am trying to find out if the pulse in the figure satisfies the Nyquist criterion for a modulation interval T. I'm used to the Nyqusit frequency, but I cannot grasp what the Nyquist criterion is ...
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### How to determine sampling frequency for an x(t) signal avoiding aliasing?

The antitransform of the function is given: $\hat{x}(f) = \frac{123 + i246\pi f}{246 - 24600 \pi^2 f^2 + i4920\pi f}$ I'm asked to determine which frequency can I sample using the function x(t) ...
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### One sided frequency spectrum (Matlab vs. Origin)

There are a lot of queries on fft frequency all over the web. I guess the following point not discussed anywhere explicitly. Hope someone can provide an insight here. If we have and even number of ...
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### Amplitude Response at greater than half the sampling frequency

I am hoping to clear up some confusion I have. In a lab I am taking, we analyzed the amplitude response of a simple system. We found that as we increased the input signal frequency to greater than ...
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### Power Line interference with different Sampling frequency

I've been playing around with EEG data from an online database. If the power line interference (PLI) is at 50Hz and sampling frequency is 64Hz, then according to the Nyquist theorem, the 50Hz PLI ...
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### Estimating the Nyquist rate when simulating data

I want to find the power spectrum $\tilde{Q}(\omega)$ of a quantity $Q(t)$. The values of $Q$ are computed at discrete time steps so I have a series $Q(\Delta t)$, $Q(2 \Delta t)$, ... of values, but ...
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### Reconstruct under sampled signal

I have a signal from a PWM inverter that was sampled at 3,84 kHz. The PWM has a switching frequency of 5 kHz. The pwm signal is feeding an induction motor. If I low-pass filter the PWM signal it ...
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### Sampling theory and frequency spacing

If a CT signal $x(t)$ is sampled for one ($1$) second and $4096$ samples are generated: Isn't the highest frequency that can be sampled without aliasing ($4096/2$) $2048\textrm{ Hz}$? If a $4096$ ...
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### Elegant way of calculating minimal sampling frequency without aliasing for annoying signals

Given a symmetric Fourier transform with finite support as below, there's an algorithmic procedure to determine the minimal frequency for sampling without aliasing: Find an integer $L>1$ ...
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### What is the maximum allowed transition band of the low-pass filter used in the reconstruction kernel for a CD with maximum speech frequency of 4 kHz?

My question is if the transition band in the question below would be from 4Khz to the Nyquist frequency of 22.05Khz or from 4Khz until 44.1Khz-4Khz=40.1Khz?
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### Noise Peaks Near Nyquist Frequency

I am working on an audio upsampling/oversampling project where I am testing different interpolating schemes in hardware and comparing measurements to my expected results. In one of my interpolating ...
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### Relation between bandwidth and data rate

I have trouble understanding the following from wikipedia - Bandwidth (Signal Processing) A key characteristic of bandwidth is that any band of a given width can carry the same amount of ...
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### Choosing minimum sampling frequency of a filtered signal

I have a time series of acceleration sampled at 1000Hz to capture random impacts on a structure. The ringing of the structure (not of interest) produces noise which a 50Hz filter seems to eliminate ...
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### ISI Nyquist criterion and spectral efficiency

While reading Bernard Sklar's Digital Communications book I've got confused with ISI Nyquist criterion (not Nyquist rate criterion). There is stated (Sklar, 3.3 section) for symbol rate $R_s$ minimum ...
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### 100 kHz sinewave contaminating a signal sampled at 48 kHz

If sampling at a rate of 48 kHz, with no anti-aliasing filter on the input, and the input signal is contaminated by a 100 kHz sine, at what frequency would the sinewave signal appear in the output ...
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### Sending a Filtered vs Non-Filtered speech over a Communication Link

To send a $10 \, KHz$ bandwidth of speech (Non Filtered speech), Nyquist criteria says that sampling duration should be $50 \, \mu s$. While for a $4 \, KHz$ bandwidth of filtered speech, sampling ...