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

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7 views

Finding peak width (FWHM) using Python on a multi-peak dataset

Here's my denoised data: I've calculated my peaks, but if I define the peak width as full width at half maximum (FWHM) (while assuming zero is defined as the smallest point in data between ~25 to ...
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2answers
13 views

DFT vs FFT: does odd number works for DFT only?

I am always confused between FFT and DFT. In both algorithm, it has been assumed that the signal is periodic (so my understanding is that, if you have a 20 sample point signal, and you do DFT or FFT, ...
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1answer
36 views

I saw this question on one of the sites related to DFT

The analog signal x(t) is band-limited to 40 Hz. Suppose the signal is sampled at the rate of 100 samples per second and that at this rate 200 samples are collected. Then 200 zeros are appended to the ...
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3answers
96 views

when is a kalman filter different from a moving average?

this thread asks when a discrete-time Kalman filter is better/different from a simple moving average of the observations: ...
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1answer
29 views

kalman filter with time-varying noise?

in regular discrete-time (1 dimensional) kalman filter, it is assumed that we have white gaussian noise affecting the transitions and the observations: $x(t+1) = Ax + w$ $y(t) = Cx(t) + v$ ...
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15 views

How can I generate an NxN DHT matrix? without any predefined function [closed]

How can i generate the DHT matrix without using any predefined any function
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61 views

Time frequency domain analyis of signals

In the time frequency domain I have used the following denoising methods Thresholding or schwirnking - Soft,Hard,Median and with methods (minimax, adaptative and sure). However if recomposing the ...
2
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4answers
106 views

What is the sampling rate in this case?

A signal $x=\sin(\pi t/4)$ sampled at every $t=1$ sec. so $T=1$ sec Sampled signal is then $x=\sin(\pi n/4)$, What is the sampling rate in this case?, And according to Nyquist sampling rate what ...
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2answers
97 views

What is meant by *sampling* in terms of the *sampling theorem*?

Let $y:\left(-\frac T2,\frac T2\right)\to\mathbb{C}$ be a square integrable function. The Fourier coefficients of $y$ are $$\underline{Y}(k):=\frac ...
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2answers
55 views

Negative values of the FFT

I try to describe a simple signal in the frequency domain with the use of FFT function: ...
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3answers
60 views

Sampling theorem and signals explained to a mathematician

Let $f:\left(-\frac T2,\frac T2\right)\to\mathbb{R}$ for some $T>0$. The Fourier coefficients of $f$ are $$\left\{\begin{matrix}a_0&=&\displaystyle\frac ...
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1answer
95 views

Is multirate signal processing involved in ADSL?

Telecom companies offer different data rates for home/office purposes depending on the money they pay. How are the telecom people able to control the flow of data of different cables. Say supposing a ...
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1answer
36 views

Super trivial question: What is a good symbol for DTFT

For a lot of applications the DTFT of a discrete time serie is just written as $DTFT(x[n])$ Just to be consistent with almost all the other integral in existence, is there a good symbol used ...
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0answers
29 views

What is the best book on Digital Signal processing for math majors? [duplicate]

I am a math major and have knowledge of Calculus, Real and Complex Analysis,PDEs and probability theory. I would like to get started with DSP and need a book suitable for math majors. Please give your ...
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0answers
28 views

What is the capacity of MIMO channels with deterministic interference plus random noise

It should be obvious that if there is no interference but only zero-mean random noise, as it is discussed in many textbooks. When there is known deterministic interference, what is the capacity now? ...
0
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1answer
37 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
25 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
6 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 ...
4
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0answers
50 views

Can someone please help in simplifying the Fisher information: Help in understanding the steps in paper

I am unable to calculate the Fisher Information matrix and the CRLB of an autoregressive model from the observations $x$ in the format of the CRLB calculated in the paper "Efficient estimation of ...
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1answer
55 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
43 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, ...
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1answer
46 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
301 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
44 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
36 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
14 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 ...
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0answers
26 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
34 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 ...
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4answers
57 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
108 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
185 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
47 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 ...
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1answer
34 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: ...
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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
38 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 ...
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2answers
70 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
15 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
33 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
71 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
33 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
41 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
94 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 ...
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1answer
69 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 ...
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0answers
20 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 ...
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1answer
53 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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32 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
35 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 ...