# Questions tagged [discrete-signals]

A discrete signal or discrete-time signal is a time series consisting of a sequence of quantities.

358 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
71 views

### How to draw a finite-duration sequence

On page $359$ of the 2nd edition of the book "Signals & Systems", by Oppenheim and Willsky, the authors wrote the following words: "Consider a general sequence $x[n]$ that is of finite duration. ...
29 views

### IID noise assumption at Matched Filter sample time

I read that at the correct sample times of a matched filter output the noise is independent assuming a Nyquist pulse. Can someone provide a proof of this or explain it more? Assuming your matched ...
25 views

### Applying Wavelet on energy disaggregation as denoising technique to remove uncertainties

I would like to apply Wavelet in MATLAB as a denoising technique on Non-Intrusive load Monitoring data. The data was captured by sensors on each appliance and one sensor on the smart meter (Normally ...
39 views

### Deep Learning based NDA Channel Estimation

I was wondering if it is possible to use Deep Learning to estimate the Channel Impulse Response for NDA synchronization? I understand Deep Learning is not normally used for regression problems but I ...
356 views

### How to convert from Laplace Domain to Time Domain?

I want to convert the following equation from Laplace domain to continuous time domain: $F(s) = \frac{-2 m k v R}{2 m R s^{2} + m k s + 2 k R}$ m, k, v, R are all constants. If I can factor or put ...
26 views

### Are discrete time functions expected to be this inaccurate?

I am attempting to test some discrete time functions against their continuous counterparts and I am surprised by how inaccurate the discrete versions are coming out. I am modeling the displacement, ...
107 views

### inverse discrete FFT in python, multiple times?

I was wondering what really happens when taking the inverse discrete FFT on some set of numbers, for 3 times? Because looking at it, it looks like we're getting an output that is identically with the ...
84 views

### Reconstruction of sampled band-pass signal

I am pretty new to signal processing. I am currently trying to reconstruct a sampled band-pass signal created with the filtfilt and ...
22 views

### How to compute the energy of a NON-STATIONARY (transient) random discrete-time signal

When computing the energy of a NON-STATIONARY (transient) random discrete-time signal $x(n)$, does it make more sense to compute the energy as $E=\sum_1^N{x^2(n)}$ over all the $N$ samples or does ...
61 views

### How to sketch this multirate system spectrum?

In the following system: The signal x(n) is upsampled by 2 and then filtered. The signal and the filter have the following spectrum: After upsampling the spectrum of X would look the same except ...
45 views

### How to remove sum and difference terms while computing frequency from fft?

I am currently operating in vhf band AND trying to detect frequencies using Fast Fourier transform thresholding method. While detection of multiple frequencies , i received spurs(May not appropriate ...
88 views

### Ways to differentiate three respiratory signals

I have three 1-min respiratory signals I derived from ECG signals. I am wondering if you guys have any suggestion on differentiating those three? The red line represents the experimental signals and ...
127 views

### DFT truncation of signals

How can I calculate 8 point DFT of signals whose length is less then 8 ( say 2,4) then what will I assume other members in formulae "0" or rotation or keep repeating the same two numbers Consider I ...
22 views

### Detecting changes in signal due to server delay

I'm currently working on an application that can be used to determine when a signal changes due to a server delay. Essentially, I have an API that is used to output data to a UI. However, for reasons ...
67 views

213 views

### Discrete-time, second-order section, direct-form II filter

I found dfilt.df2sos in Matlab and trying to figure it out how do I do that in Python? Is there any function that works similarly with the Matlab function? I also ...
510 views

### Please explain Multiplication property in Z transform?

I am having problem visualizing contour any example will be great help. As far as as where I need it I was trying to find Z transform of a contracted signal by first multiplication by impulse train.
46 views

### Interpreting Auto correlation results

I used xcorr function in Matlab to compute the autocorrelation of my signal. I obtained a graph, which is shown below. How to interpret this? I read that autocorrelation helps in finding the patterns ...
52 views

### How to low pass very few samples

I'm asking myself what is the best way to low pass a signal which only has a few hundred samples? Or is there a proper way at all? It must not be a sound signal but I used Audacity to display the ...
88 views

68 views

### How can I find a relation between the input and output of the overall system?

I have system for filtering a continuous-time signal using a discrete-time filter where sampling is performed by multiplication with the impulse train. The frequency response of the discrete-time ...
37 views

### Sampling Process Question

This is what I know about the basic sampling process I am told that fbar(t) (i.e the sampled signal) is defined for all t. I don't understand that. If n is a finite integer (..,-3, -2, -1, 0, 1...), ...
22 views

### Find which groups of ants are coexisted in the location from their signal profiles using NMF

I try to solve biological problem to tell which groups of ants are co-existed at this location by their sounds in specific time frame. My chosen framework is Non-negative Matrix Factorisation (NMF) ...
136 views

### Amplitude problem by puting 5 FIR in a row

I'm trying to use 5 FIR in a row to improve the S/N ratio on my signal, but I have some difficulties doing it. In fact I have 2 signals, let's call them sig_I and sig_Q. I want to apply my 5 filter ...
19 views

### Join 2 NMF models where dictionaries has hierarchical structure

I have two NMF models $A = W_1A_{dict}$ and $B = W_2B_{dict}$ (where the $W$ represents weight coefficient matrix). What is a good way to join two NMFs if I know each column of $B_{dict}$ is summed up ...