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

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21 views

What is bispectrum?

I am working on a project that uses EEG signals of the brain to identify emotional states. While surveying the literature, I came across several references where "derived features of bispectrum" are ...
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0answers
11 views

multidimensional signal means more than 2 independent variables and amplitude being dependent variable?

Does multidimensional signal mean more than 2 independent variables and amplitude being dependent variable? Can we conclude mathematically that the number of independent variables increases if ...
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0answers
5 views

How do we find the SNRseg if I have a block with 2D in time domain

I always get the answer -.0017 and it suppose to have some negative number around 30. I get the average for the plane voice then the average for the difference between plain and the encrypted voice ...
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0answers
23 views

Unable to calculate the CRLB for Gaussian mixture model

I am unable to follow the steps needed to derive the Fisher Information matrix and the CRLB of an autoregressive model from the observations $x$. The AR process is excited by non-Gaussain sequence, ...
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1answer
35 views

System Properties; Linear, Causal, Time-Invariant, Stable?

I know the answers of the below question but I dont know why, except linear, could you explain the rest? Small tick: correct, small tick with dash incorrect answer.
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2answers
38 views

Is DCT basicly a filter?

I am reading about audio processing for my university project and I found out that DCT basicly filters out some frequencies. I wanted to use for example high-pass filter and then DCT for compression, ...
0
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1answer
42 views

Discrete Time Fourier Transform to Frequency Domain

I failed to do this question on the exam and finding it very difficult, I would be glad if you can help me solve it. How shall I start?
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4answers
254 views

Difference between Digital signal and Discrete signal

I have just started studying Digital Signal Processing. Can someone explain what is the difference between a Discrete Signal and a Digital Signal in simple words? Thanks in advance !
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0answers
33 views

A problem about L0 norm Compressed Sensing

I want to reconstruct signal $\boldsymbol{x}_i $ from $\mathcal{F}(\boldsymbol{x}_i) = \boldsymbol{y}_i$, where $ \boldsymbol{y}_i $ is undersampled and $i \in \{1,2\}$. I know $\| \boldsymbol{x}_i ...
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1answer
35 views

All pass systems- Poles and Zeros

If an All Pass system has poles at $0.8\exp\left(-j \dfrac{\pi}{4}\right)$ and $0.8\exp\left(j \dfrac{\pi}{4}\right)$, There would be $2\pi$ jumps in the phase (principal value) at angular frequency ...
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0answers
12 views

EZW parent-child relation

I’m trying to learn the EZW principle. I’m having trouble understanding the parent-child relationship. In my case, I want to use it on a 1 dimensional signal. So, let’s say for example a signal of 4 ...
-2
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0answers
22 views

Hamming Code problem

Let 1 0 1 0 0 1 1 0 1 0 0 1 0 0 1 be the parity check control matrix of a linear block code. Determine n and k Find all the codewords. Find the correcting and detecting capability. Determine ...
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0answers
24 views

Help in blind deconvolution by MLE of 1 D signal

[Paper - A computationally fast approach to maximum-likelihood deconvolution by Chong-Yung Chi, Jerry M. Mendel and Dan Hampson link presents an ...
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1answer
26 views

How to narrow the frequency band of a wavelet

I have a ricker wavelet with a dominant frequency of 15 Hz. The fourier transform shows its frequency band is almost to 50 Hz. How can I narrow the frequency band of this 15 Hz ricker wavelet? I ...
0
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2answers
24 views

Trying to recreate sawtooth and square wave in Matlab

I've been asked to recreate the square and sawtooth wave shown below: And I've managed to recreate the square wave form but I can't seem to get my sawtooth wave to match. ...
2
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1answer
104 views

Shouldn't the Sampling Theorem imply that there should be no information loss at all after a signal is processed?

I am very, very new to signal processing (only started a few days ago) so please bear with me because I may be missing the big picture. Consider an arbitrary signal $x(t)$ with varying frequency to ...
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2answers
171 views

Understanding circular convolution

Let $a$ and $b$ $\in \mathbb C^N$ and $a[k] = a[k \mod N]$ (same with b). Then the circular convolution of $a$ and $b$ is defined by $$ (a * b)[n] = \sum_{p=0}^{N-1} a[p] b[n-p].$$ I have a problem ...
0
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1answer
45 views

Analog signal can be discrete time?

I am new to this site and field too.I always thought analog is continouos and digital signal is discete. I read this today and got confused about analog signal Analog can be >continuous time(CT)or ...
1
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1answer
32 views

snr calculation when noiseless signal is not known

I have a noisy signal.Then using filtering techniques i got the estimated noiseless signal.I dont have the original noiseless signal.I have calculated snr the following way: ...
0
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1answer
71 views

contrast curves problems

I am doing some tests about local/global contrast algorithms and need a simple equation to define an arbitrary S-shaped contrast curve. It's simple if the turning point is assumed to be (0.5, 0.5), ...
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1answer
33 views

Critically sampled Laplacian Pyramid from 2nd generation Wavelet

I'd like to know if a technique I have in mind is already used and has a name I can look up, and whether it is likely to work and be useful! My aim is to produce a discrete wavelet transform that is ...
1
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3answers
58 views

Normalization purpose in signal processing

What is the purpose of normalizing the signal? If we have two signals on hand, how is it used when comparing these two signals?
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0answers
13 views

Barrier load cell digitial filtering with known pre-collision noise

I have a signal processing (filtering) problem that I would love to bounce off the community and receive some feedback. First, the context: Longitudinal barrier load cell force-time data for high ...
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0answers
31 views

Detecting the durations of randomly occuring sinusoidal pulses

I’m very new to signal processing and eager to learn, but please be gentle… System: I have a single input channel receiving a 44.1kHz 16bit PCM signal. For the majority of the time the channel will ...
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0answers
30 views

Adaptive Line noise removal using IIR notch filters

I'm trying to filter out line noise(60Hz and 120Hz) from a EEG signals received over a bluetooth link. I'm proposing to use a IIR notch filter to filter out the line-noise which varies w.r.t to ...
2
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2answers
68 views

Effects of DC offset on a signal

What are some of the reasons why DC offset is considered undesirable for a timeseries signal other than wastage of power during transmission ? Specifically, How does it cause spectral leakage and out ...
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0answers
29 views

How to simulate two OFDM Users with low complexity FFT/IFFT?

have two User one of them sending over freq (0-B] and the other transmit over (B-2B]. Both of them are using OFDM and each one has Nc subcarriers. I wanted to simulate the received signal using ...
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0answers
29 views

Reconstructed signal amplitude issue

I have already posted this in stack overflow . Reconstructed signal amplitude is not matching with true signal. What I'm missing here for perfect reconstruction. sfd is signal in frequency domain, N ...
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2answers
35 views

Understanding Arrangement of second order sections

When splitting higher order recursive filters into more convenient 2nd order sections (biquads), in matlab, we usually use zp2sos to convert. In document, there's a ...
1
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1answer
56 views

Derivative of signal with missing samples

I have software that tracks an object moving (in the x-dimension only) across a video shot from a stationary camera. I need to find the velocity and acceleration of the object as functions of time. ...
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1answer
56 views

Matlab: How do I implement the Expectation operator for time series

I have the output of a time series y(t) which is a vector for t = 1,2,...m denoting the number of data points. Q1: If ...
0
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1answer
68 views

Mixing two signals creates power at dc?

I have a signal with components at 1200 and 1800 Hz. When I mix this signal with a 1500 Hz signal to create components at -300 and +300 Hz (then LPF) a DC offset presents itself when the input signal ...
0
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0answers
18 views

Nth Order Differentiated Parabolic Wave Synthesis

I am working on a sound synthesis software project. At the moment I am working on an implementation of the "Differentiated Parabolic Wave" or DPW algorithm in C++, specifically a sawtooth ...
-1
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1answer
49 views

Confusion when applying Hamming window to signal

I am writing some code which takes a signal of length $n$, and processes it in 20 ms chunks with 5 ms of overlap... So basically I have a buffer of 20 ms worth of sampled data, and I am trying to ...
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0answers
31 views

How to choose sampling rate?

I am working on a FMCW radar and I want to sample the I/Q signals from the 2 receiving antenna (total 4 channels) simultaneoulsy and send the digital data to computer to extract range and velocity ...
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0answers
29 views

Why do we use Hilbert Transform in discrete time domain?

I have few questions regarding hilbert transform, Questions are as follows: 1)What are the benifits of using hilbert transform hardware and software point of view? 2)Cannot we use any other digital ...
0
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0answers
71 views

Problem in Implementing Cyclostationary Feature Detector in Matlab

I have Implemented this detector in AWGN channel in Matlab but I am getting vague result. As it performance doesn't vary with change in SNR. Its very strange result for me. I don't know what mistake I ...
1
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2answers
48 views

Why is my discretized transfer function unstable when my discretized state-space model is stable?

I am working with a 30-state, 14-input linear model that is described by a state-space model: model_state_space = ss(A, B, C, D); The model is extremely slow (it ...
1
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1answer
31 views

What is the use of the Welch lower bound when k > 1?

The Welch lower bound on the maximum cross-correlation (inner product) of $m$ vectors, each of $n$ elements, is given by $c_{max} = f(m, n, k)$ (eg, see Wikipedia Welch bounds). It is always assumed ...
0
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1answer
80 views

How to show that y[n] = x[n] * h[n] turns into the Y(z) = X(z).H(z)?

I'm trying to show that $y[n]=x[n]*h[n]$ turns into $Y(z) = X(z)H(z)$ in Z-domain by first applying convolution then by taking the inverse Z-transform of the $Y(z)$, stating that it's the same ...
0
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1answer
33 views

DFT independent variable as fraction of sampling rate

When the frequency domain's independent variable is labeled as a fraction of the sampling rate, the values along the horizontal axis always run between $0$ and $0.5$, since discrete data can only ...
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0answers
34 views

Different methods of periodicity detection of irregular signal

I'm going to describe the situation and the solutions I've tried and then ask some questions. The data The data I'm working with is sampled once per second and there either was an event (1) or not ...
0
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1answer
63 views

Is it possible that adding noise to a signal can increase detection possibility?

I am simulating a feature detector in noisy environment which consist of AWGN Noise and Impulsive Noise. But I am getting a strange result as Signal with Impulsive+AWGN noise has better detection ...
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1answer
25 views

How to apply “Substitution Method” in Difference Equations?

How to get the value of $y_p(n)$ using substitution method? What exactly do we need to substitute to get the value?
1
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1answer
149 views

Image super resolution algorithm in Matlab

I'm trying to implement a simple Image super resolution algorithm (DWT-Based Resolution Enhancement ) in the following paper http://www.ripublication.com/aeee/52_pp%20%20%20405-412.pdf I tried to ...
0
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1answer
30 views

Deriving time-scaling property for Fourier Series

thanks for taking the time to help with this problem! I have to prove the time-scaling property: $$ x_{(m)}[n] = \begin{cases} x[n/m], & n=0,\pm m, \pm 2m,...\\ 0, & otherwise \end{cases} $$ ...
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0answers
46 views

For discrete signals, why does phase change not correspond to time shift?

I'm going through a Signal Processing lecture where the professor mentions this fact and the argument given is: Suppose you have a sinusoidal signal: $Acos(\omega t)$ Now if you change the phase of ...
0
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1answer
62 views

Extending a waveform

Apologies if this makes no sense or seems rather simple, I'm a Matlab newbie. Basically, I've got a .wav audio waveform which I am resampling to various different frequencies and then trimming the ...
0
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1answer
34 views

Estimating signal strength from PCM-encoded signal

I am processing rtl_fm output (in time domain), extracting Manchester encoded bits. I can detect preamble and, therefore, decode the message which follows the preamble. This is how my signal looks ...
1
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1answer
70 views

Removing frequency using FFT

So if I were to have an $n$ length sample of a given sample rate and were to run it through an FFT, resulting in $n$ complex elements. How would I obtain the frequency bins, such that if I know the ...