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

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Time delay analysis in different binary sequences

I am extracting a property of a signal which I represent with either a 0 for absent or 1 for present. This property is extracted for each data point in a time series and in the end I am left with a ...
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2answers
35 views

Decimate/downsample a signal from 1920.93Hz to 1920Hz. Possible?

I've just learned that the A/D converter I am using is not sampling at my desired sampling rate. I request 20 seconds of data at 1920Hz and I receive 38400 points of data that were actually sampled ...
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1answer
43 views

Intertial navigation on android phone with Kalman filter

Ok, so suppose I've got a phone with gyroscope, compass and 3-d accelerometer. I wanted to track position of the moving phone for about 1 minute with let's say 50 mm accuracy. Actually let's say that ...
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2answers
63 views

Negative dB signal to noise ratio

Is it common to find systems having signal to noise ratio (SNR) less than 1 i.e. noise is more than signal? I am currently working with SNR of -5db to -20db. And how useful is it to work with sensor ...
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2answers
40 views

What is 'energy compaction' in simple terms?

This is my understanding of 'energy compaction' and want to know if it is right. Take a vector. The energy of the vector is the sum of the squares of its elements. If A is the transformation matrix ...
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36 views

DTFT of an infinite sequence

We want to find the DTFT (Discrete Time Fourier Transform) of a infinite sequence of consequtive numbers ones (1) and -ones (-1). The length of ones are 8 as well as the length of -ones (-1). For ...
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2answers
34 views

shifting sequences using Matlab

I'm reading this book and I came across a function to shift sequences. Mathematically, $$ y(n) = \{x(n-k) \} $$ if $m = n-k$, then $$ y(m+k) = \{ x(m) \} $$ ...
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1answer
12 views

How to model the dispersion which introduces a modulation driver of EML?

I need to model the dispersion which introduces a modulation driver of EML, in matlab simulations. The parameters are: Lambda: 1310nm PAM4 power: Pmax = 1.09 mW Pmin = 0.13 mW Bandwidth = 56Gbps
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1answer
39 views

DSP - Understanding Formulas

I am a beginner in DSP but get confused when some formulas like below are referred: ...
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1answer
57 views

Detecting sound inside a sound

I was searching on the Internet hopelessly about some materials regarding detecting a sound in another sound. Say, I've got a recorded short sound (which may be anything, fragment of speech, fragment ...
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1answer
48 views

how to get the phasor(frequency domain) representation of a digitalized signal?

I know that we can get the phasor representation(frequency domain) of a signal through Fourier transform, but the picture above gives a method that can get the phasor representation of a signal in a ...
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23 views

denoising signal using DWT

let us consider following program for denosing signal using DWT ...
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1answer
58 views

Non-uniqueness of continuous time sinusoids?

I have read the DSP literature and I get why: $$e^{j(\omega+2 \pi m)n}=e^{j\omega n}$$ But can't we prove the same in continuous domain also in the following way: $$e^{j\omega t}$$ $$e^{j(\omega+2 ...
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1answer
47 views

Simulate a pulse of specific power

Suppose you produce a pulse x in discrete samples of duration dt each (e.g. in Matlab) according to a function. I was given some ...
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1answer
57 views

Digital Gaussian White noise signal generation in C++

I am trying to generate a band limited noise signal on a Raspberry Pi. I calculate samples at every 1/48000 sec on the Pi. If I generate normally distributed random numbers as data points at every ...
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1answer
34 views

Discrete signals notation underlined value

In a book i have there's an exercise that want to find the output of a system for a given signal system: $ 2y(n)=2x(n)+x(n+1)+x(n-1) $ input : $ Χ=[\underline1, -1, 2, 0, -2, 0, 1 ]$ $Χ1=Χ[0] $ ...
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2answers
86 views

When should we using moving average in algorithm design?

I'm new to signal processing. And I just read G.720.1. I find there is a lot of moving average used. And I can also recall there is a lot of moving average been used in other audio processing ...
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1answer
81 views

How can I load a wav file, split it in frames, apply different filters do different frames and then recombine the filtered frames into a single file?

I'm working on a wav audio file using MATLAB. What i would like to do is: load a wav file and divide it into frames of the same dimension filter these frames (with a different filter for each ...
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1answer
57 views

Inverse DTFT of $e^{-j\omega}$

I've been trying to solve the following problem, but I noticed that I get two different answers by means of two different techniques: Find the impulse response, $h(n)$, of the following system, ...
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36 views

Noisy Signal auto/cross-correlation

I am trying to understand the basics of the cross/auto-correlation if the noisy signal $y(t)$ which is received from the channel at the receiver. Here at receiver we want to estimate the noise in the ...
2
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0answers
83 views

Least Angle without matrix inversion?

Sorry if this is too damned long. I did what I could to abbreviate it. I'm new to numerical work with matrices. I believe I have a way to compute Least Angle without explicit matrix inversion. I'm ...
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1answer
115 views

Under what condition is the available bandwidth $f_s$ instead of $\frac{f_s}{2}$?

Can someone help me with this interview question? It is about the sampling frequency rate. Under what condition the available bandwidth is $f_s$ instead of $\frac{f_s}{2}$?
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1answer
87 views

Implementations of Low-Pass Filter

I should say which of the filters from the following image implements an ideal low-pass filter with cutoff frequency $\frac{\pi}{4}$. In the picture, Sa is a zero insertion filter, which inserts a ...
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2answers
100 views

Causality of Linear Phase Filter

If a digital LTI filter has phase response on the form $arg[H(e^{jw})] = -\alpha\omega$, what could one say about it's causality (and consequently, the causality of it's impulse response)? Also is ...
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1answer
43 views

How to represent the following system function in a block diagram?

I am aware that this a simple question, but I haven't been able to find a single reference that explains this situation. The system function is: $$\frac{1}{1-(0.3)(1+j)D}$$ How can one draw a block ...
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1answer
484 views

Difference between discrete time fourier transform and discrete fourier transform

I have read many articles about DTFT and DFT but am not able to discern the difference between the two except for a few visible things like DTFT goes till infinity while DFT is only till N-1. Can ...
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1answer
118 views

how to apply Short-time fourier transform to code in matlab

Please Help, I have a white noise signal that I created and need help to apply the Short-time fourier transform to my code so that it can do the bandpass filtering. I am trying to put it in the code ...
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32 views

How to perform a Stockwell Transform on a 2D matrix

I was looking at performing a Stockwell transform on a matrix (or an image as it has two directions - the matrix I am interested in has a spatial dimension and a time dimension, but this should make ...
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1answer
64 views

How moving part pixel intensity values of video frames becomes dominant compared to stationary part intensities in reconstructed frames?

Hello everyone i want to do dynamic texture video sementation using the Fourier transform in MATLAB. I am applying 3-D fft on dynamic texture video frames (using matlab function 'fftn') and ...
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2answers
93 views

I have a mix signals (2 signals with different dc offset). How to recover another dc value which has been buried by the stronger dc value?

Let say I have a time-varying signal which is a mixture of two signals with different dc offsets. If I apply the fft on that signal, I will only get the dc value (at f=0hz) with stronger energy. How ...
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1answer
59 views

Finding linear convolution of two time series

PROBLEM Two real, causal time series $$f_k = a^k \quad \text{and} \quad g_k = b^k$$ where $a \neq b$, $|a| < 1$, and $|b| < 1$, are given for $k = 0,1,2,...$ Find the linear convolution ...
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1answer
65 views

Before the birth of computers how people calculated the bandwidths?

In these days we can able to easily calculate the bandwidths with the help of technology, but in olden days where people used the analog phones, how did they calculated the bandwidths?
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1answer
41 views

Can a discrete sinusoidal signal represent only limited number of frequencies?

If $\omega$ is the frequency of a continuous time sinusoidal signal, $-\infty < \omega < \infty $. But when it comes to discrete time sinusoidal signals, the range becomes limited : $-\pi \le ...
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1answer
55 views

Playing/Recording acoustic signal in matlab to tell difference between 2 sounds

I will be using one central node/latop to play a tone and will have a second node/laptop to record and read the sound and be able to say this node is on the left or right. So trying to figure out the ...
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29 views

Data Processing Question

I'm curious if there is a method to separate the signal from the noise in this kind of data set, other than manually do it by indexing. the top plot is the data, the bottom plot is the zoom in of the ...
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1answer
68 views

circular Convolution

Multiplications of time domain vectors of two signals is equivalent to convolutions in frequency domain and also use circular convolutions for when FIR filter design using window method in frequency. ...
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2answers
86 views

Discrete Fourier transform of complex time series

I am working through previous exam questions for a class I'm currently taking in signal theory, and one problem, although it looks easy, stumps me. PROBLEM Two real $N$-periodic time seires $f_n$ ...
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1answer
78 views

Rate of fall of sidelobe level

Anyone can explain me about how measure side lobe roll-off rate of kaiser window from Spectrum in matlab where side lobe roll-off rate is the asymptotic decay rate, in decibels per octave of ...
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2answers
204 views

the difference between dft and dfs

in the literature i've found that dfs and dft are one and the same.if they are one and the same why to use two different names for them? if there is really a difference what is it and what is the ...
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46 views

Fast Walsh-Hadamard Transform frequency spectrum?

Can the Fast Walsh-Hadamard Transform be used to find a Walsh-Hadamard frequency spectrum which some how relates to a Fourier frequency spectrum? Is the Fast Walsh-Hadamard Transform more accurate ...
0
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1answer
83 views

Discrete Hilbert transformation of a spatial signal

first of all, sorry for this basic question in signal processing, I'm pretty new in this field and have been stuck in a situation a little beyond my expertise. The idea is to derive the instantaneous ...
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66 views

Research on signal processing [closed]

Inspired by the talk "You and Your Research" by Richard Hamming, I started wondering what are the important research topics on signal processing nowadays. Certainly an extensive list of topics would ...
2
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2answers
94 views

Low-Complexity Audio Compression?

What options exist for discrete audio compression that is good quality, moderate compression (e.g. 3+:1), and low complexity (e.g. hundreds of processing cycles to encode each sample without the use ...
3
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2answers
88 views

Window functions with rippleless spectra

On Wikipedia I found the Hann-Poisson window, and the article claims the spectrum is smooth, but it isn't theoretically smooth, as it turns out. In practice you achieve partial smoothness by jacking ...
2
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2answers
211 views

How to quantify asymmetry of a signal?

I'm looking for a suitable measure in order to quantify the asymmetry of a signal. I've read this: Detect signals degree of imbalance and this: How to measure the agreement between to curves? but I ...
2
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1answer
67 views

Generating a time series given a transfer function

I'm trying to work my way through a paper I found online, titled "Three Models of Wind-Gust Disturbances for the Analysis of Antenna Pointing Accuracy" by W. Gawronski, 2002. ...
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1answer
91 views

How does time shift correspond to phase change in a discrete signal?

I was watching this video where the presenter remarks: For a discrete signal, time shift corresponds to phase change in a discrete signal but not vice versa. I was trying to figure out how ...
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20 views

Estimate the type of wavelet transform in receiver side

Suppose that a signal is decomposed by using discrete wavelet transform (DWT) and transmitted. Is it possible for receiver to find which type of wavelet is applied in transmitter side ? I mean, if ...
2
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2answers
107 views

Why would you use DCT as oppose to DFT for detecting oscillation in a signal?

For my project, I needed to detect the primary oscillation frequency in a signal data. As I googled around, it turns out that DCT is the best tool to find this ...
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1answer
56 views

Autocorrelation function of a discrete signal

For a certain experiment of which I have data, I want to calculate the autocorrelation of the measurements. For this I used the expression from http://en.wikipedia.org/wiki/Autocorrelation#Estimation, ...