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0
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1answer
27 views

transfer function and 'causal' signal - evaluate transfer function or use z-transform of input?

From my studying difference equations and transfer functions, I understand that when a complex exponential input $x[n]=z_1^n$ is applied to an LTI system with transfer function $H(z)$, determining the ...
0
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0answers
10 views

Planar image tracking VS object tracking performance

I've been developing AR-apps for android and I had jumped right to unity and ready-to-go SDKs having little time to learn the basics. I'm familiar with algorithms for feature points detection and ...
0
votes
0answers
21 views

should block diagrams in Direct Form 1/2 contain empty branches to fit structure?

When creating a block diagram in a well-recognized structure (Direct Forms 1&2 in particular), does one remove branches where the coefficient is 0? This picture includes a coefficient of $b_1=0....
0
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0answers
23 views

What does “high dynamics” mean?

While reading some research papers about phase-locked loops, I have come across with the term "high dynamics" several times, for example: ... the signal may be affected by high dynamics ... ... being ...
0
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0answers
9 views

source separation: the tracking capability of the inverse (unmixing) system in a nonstationary environment?

I'm reading Nonnegative Matrix and Tensor Factorizations (A CICHOCK, p.4). There is a paragraph talking about the inverse system should have the tracking capability. From my understanding, the inverse ...
3
votes
2answers
8k views

What is the Fourier Transform of a constant signal?

I am trying to figure out what the fourier transform of a constant signal is and for some reason i am coming to the conclusion that the answer is 1. Or better yet a step function.
3
votes
2answers
671 views

Is sampling at double the desired reproduction frequency accurate?

This is probably a general principles question, though I'm thinking specifically in relation to sound, which is commonly sampled at a rate of 44.1 kHz in part because the maximum frequency the average ...
0
votes
3answers
166 views

What really means stochastic in field of signal processing

I met two definitions of word stochastic, the first one (cited from wikipedia Stochastic) The word stochastic is an adjective in English that describes something that was randomly determined The ...
0
votes
1answer
155 views
4
votes
1answer
146 views

Overlapping power-of-cosine windows with constant weight

I would like to refer you to a relevant question I posed on the Math StackExchange: A generalisation of the Pythagorean trigonometric identity. As can be seen from the question and the answer, what ...
6
votes
1answer
197 views

Is there a strategy for discrete control of a system with dynamics near sample rate?

I'm trying to control a system where the controller sample rate is physically fixed and the plant has significant dynamics on the same order as the sample rate. I understand that one would prefer to ...
-1
votes
1answer
121 views

Are these Linear and Time Invariant Systems?

We were given the above systems and we were asked to tell whether they are linear (or not) and time invariant(or not). $y(m,n)=x(m,n)+c,\quad c>0$ $ y(m,n)=x(m,n)+x(m,-n)$ $y(m,n)=x(m,n+m)$ $y(m,n)...
-1
votes
1answer
158 views

Spectrum of a time-domain impulse train

I am trying to learn DSP. I'm reading the 2nd edition of Oppenheim & Schafer's "Discrete-Time Sig. Proc." book. On the topic of converting a continuous signal to a discrete-time signal the idea of ...
1
vote
1answer
36 views

Frequency range for set of all discrete-time sinusoids

Consider discrete time sinusoids of the form $$x[n] = \cos(\omega n) \ ,$$ where $n$ is an integer. What frequency range of $\omega$ would constitute all the possible sinusoids? I'm thinking that $0\...
1
vote
4answers
303 views

Finding a signals complimentary sound / frequency

I know about complimentary colors and how to get them, since colors are basically frequency / wavelengths. Is it possible to find a signals complimentary, additive or subtractive frequencies in an ...
1
vote
1answer
132 views

Baseband vs. Passband

I am a bit confused if the following signal is baseband or passband: $f(t) = x(t) \cos(2 \pi f_c t) - j \: y(t) \sin(2 \pi f_c t),$ where $j = \sqrt{-1}$. Since it is clearly not real, I cannot say ...
5
votes
1answer
3k views

Baseband vs Passband modulation

I am taking a graduate level course in Networking theory and applications and I am still a bit shaky on the difference between baseband and pass band scheming. The book I am using is Computer Networks ...
-1
votes
1answer
1k views

Integral of unit step function [closed]

Can someone help me understand how did we get from the second line to the third one? $$\begin{align} u(t-1)*u(t) &= \int_{-\infty}^{\infty}u(\tau-1)u(t-\tau)d\tau \\ &=\int_{1}^{t}u(t-\tau)d\...
0
votes
2answers
50 views

Discrepancy when calculating LTI system output using inverse z-Transform

I'm given a difference equation, $y[n]-0.4y[n-1]=x[n]$, and asked to find the natural response $y_n[n]$, forced response $y_f[n]$ and complete response $y[n]$ if $x[n]=4 (0.25)^nu[n]$ and $y[0]=0$. ...
0
votes
1answer
722 views

BIBO stability and input at system's pole

My understanding of BIBO stability is that if a bounded input is applied to a discrete-time, linear, time-invariant BIBO system, the output will also be bounded. A sufficient condition for this is ...
0
votes
2answers
158 views

Output of a discrete-time LTI system different form than input?

This question is related to this one. I'm going through old exams for a 2nd year systems and transforms course, and came across this question. I'm posting this question just in case my other question ...
1
vote
3answers
194 views

Output of discrete-time LTI system guaranteed to be same form as input?

I know that in the continuous-time context, if I supply a complex exponential input to a Linear Time Invariant system, the output will be of the same form as the input - for example, if the input is $...
1
vote
0answers
4k views

What is the difference between wide sense and strict sense stationary processes?

What is the difference between wide sense and strict sense stationary processes (SP) ? According to the definition (by Heinrich Meyr, Marc Moeneclaey, Stefan A. Fechtel in "Synchronization, Channel ...
1
vote
2answers
399 views

Does the system matrix being singular tell us anything about the system?

If we have a linear system, represented in State Space and the A matrix is singular (det(A) == 0), can we expect any special properties from the system?
0
votes
1answer
158 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 ...
-1
votes
2answers
1k views

How to compute the Fourier Transform of this ramp-like signal?

I have the following signal: and this as the solution to the problem: $$\begin{align} X(j\omega) &= \int_{-\infty}^{+\infty}x(t)e^{-j\omega t}dt \\ &= \int_0^\tau \frac{E}{\tau}t\; e^{-j\...
2
votes
3answers
258 views

Is it theoretically possible to perfectly quantize a continuous signal?

So, I'm completely new to digital signal processing, but while reading a piece this morning about quantization it got me daydreaming: could a machine ever be fast enough to sample the position and ...
2
votes
1answer
92 views

Block diagram reduction

I have the following block diagram I know that it's solution is: $$\dfrac{10 K_p}{Js^2+(B+2K_pK_v)s+10K_p} $$ But when I try to derive the solution with reduction rules I get different result. ...
0
votes
4answers
329 views

Looking to educate myself in dsp theory [closed]

I'm currently studying sound design, however over the past couple of years i started creating audio effects/instruments. I have also been programming in C++ for quite some years. I noticed my ...
11
votes
4answers
2k views

Are complex exponentials the only eigenfunctions of LTI systems?

Is there an example of an eigenfunction of a linear time invariant (LTI) system that is not a complex exponential? Justin Romberg's Eigenfunctions of LTI Systems says such eigenfuctions do exist, but ...
2
votes
1answer
862 views

QPSK, from Square Root Raised Cosine to Rectangular Impulse Shaping

I have implemented a QPSK modulator and demodulator using classic text-book examples: Square Root Raised Cosine Impulse shaping and Matched Filtering. The problem is that I've been told that I could ...
1
vote
1answer
2k views

CIC Filter vs Simple Downsampler

I' trying to implement a QPSK modulation/demodulation. At one point I have to decimate my signal by 4 for an easier implementation. I've read everywhere that the best way to do it is to use a CIC ...
26
votes
2answers
22k views

What is the advantage of MATLAB's filtfilt

MATLAB's filtfilt does a forward-backward filtering, i.e., filter, reverse the signal, filter again and then reverse again. Apparently this done to reduce phase ...
6
votes
3answers
2k views

Median Filter one after another

Operate on an image by performing Median Filtering in a 3x3 window. Operate on the resulting image by performing, again, Median Filtering in a 3x3 window. Can the resulting image be obtained from a ...
10
votes
4answers
285 views

Any references for the trade-off between software and mechanics/optics in industrial machine vision systems?

I explain my question with a simplified example. I can design an industrial vision system for the automatic inspection of an item with these main requirements: the image of a good piece must be a ...
13
votes
2answers
2k views

A (Clear) Line Between Computer Vision and Image Processing

I have been working in and learning about both Computer vision and Image processing for a few years now, and I believe that I am not a complete beginner any more. Still, after all these years, it is ...