Homework means the asker is requesting help with school homework. This lets potential answerers know that they should guide the student in solving the problem, rather than simply showing the complete answer.

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21 views

DTFT and Inverse DTFT Homework Problem

I'm trying to solve this signals homework problem: So for part a, since multiplication in the time domain is convolution in the frequency domain, I just used a DTFT table, found the DTFT for $\left(...
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1answer
20 views

Solving for frequency deviation, $\Delta f $ (FM modulation)

I'm sorry if I posted this in the wrong section. I solved the question and got $50\textrm{kHz}$, but the solution says it is $100\textrm{kHz}$ without any proof. Im asking for someone to tell me ...
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1answer
19 views

Demodulating upper sideband (USB) signals

A modulating signal $m(t)= \sin(2 \pi \nu_m t)$ is transmitted via a carrier of frequency $\nu_c$ using upper sideband (USB) modulation. Show that the USB modulated signal can be demodulated using a ...
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0answers
44 views

Response of digital filter is represented given its difference equation

A digital filter is described by the difference equation: $$y[n]-0.1y[n-1]=x[n].$$ Determine the response $y[n]$ in steady state at the entrance $$x[n]=5 \cos⁡(0.2nπ+45°)+2 \cos⁡(0.8nπ+30°)$$ I ...
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0answers
42 views

Implementing blind deconvolution in MATLAB

I want to implement blind deconvolution for the signal $ r(n) = h(n) \star s(n) + a(n)$ in MATLAB where $r(n)$ is the recorded speech $h(n)$ is impulse response of room acoustics $s(n)$ is desired ...
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1answer
29 views

How to do this root locus by hand?

I have an open-loop system function $$L(s)=6\frac{(s-2)^2}{s(s-20)^2}$$ and I wanted to to the root locus diagram for it. I did it in MATLAB and got the following graph What I don't know how to ...
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2answers
62 views

Impulse response of a continuous time system

Question The impulse response of a continuous time system is $h(t) = e^{-t}u(t)$. When $x(t) = u(t - 1)$ is input to this system what is the value of the output signal $y(t)$ at $t = 2.34$. ...
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1answer
52 views

Signal equation using signal waveform and Fourier series?

Part A: Obtain signal waveform from mathematical equation of the signal Let a sinusoidal periodical signal is represented by an equation $$y=f(t)=10+10\cos\left(\frac{2\pi f_1t}{T} +\frac{\pi}{6}\...
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1answer
52 views

Response of cascading FIR filters

I can't seem to get the right answer for this. Could someone show me the procedure? As shown in the figure a system is constructed by cascading four FIR filters having the following frequency ...
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1answer
107 views

How to calculate transmission capacity?

My textbook doesn't explain how they got the answer to this question: "If a transmission channel uses an analog carrier wave that is modulated by eight amplitudes and sixteen frequencies per bit ...
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0answers
49 views

Sampling a sinusoidal signal

Consider the signal $g(t) = \cos(2\pi\lambda t + \phi)$ that is sampled with a frequency $\tau$. Let $g_k$ denote the values of $g$ at the times $t_k =\frac{k}{\tau}$, $k \in \mathbb{N}$. (a) Show ...
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33 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,...
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1answer
41 views

Linear Time-Invariant system frequency response and impulse response given input and output in time domain

I am having difficulty with this question specifically with the $\sin()$ part. So here goes nothing: Consider a Linear Time-Invariant system with input $x[n]$ and output $y[n]$. When the input to the ...
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2answers
96 views

How to find Fourier Series Coefficients

I saw many solved examples about this topic but again I coudn't come up with any solutions about this question. How can I find the Fourier Series coefficients of the following signal ? $x(t)=2 \cos(3\...
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2answers
31 views

What is the phase of the Fourier Transform of $h(n)={\frac13,\frac13,\frac13}$ (zero position is at 2nd element)

I am using Digital Signal Processing Principles, Algorithm and Applications, 4th edition written by Proakis and Manolakis. Here is s a part that I don't understand. $h(n)={\frac13,\frac13,\frac13}$. ...
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2answers
60 views

Unable to obtain correct correct fourier transform for homework

Okay so I have this question for my homework which I am asked to find the fourier transform of a signal. However I am unable to obtain the correct answer, the question and my working is shown below. ...
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1answer
17 views

How does both shifting and scaling a function affect the Fourier Transform?

I understand how shifting and scaling work separately, but I'm unsure how to put them together. That is to say, I understand if $x(t) = X(\omega)$, $x(at) = \frac{1}{|a|}X(\frac{\omega}{a})$ and $x(t-...
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1answer
58 views

Impulse response of non-causal system

Suppose I have the following equation, where $x[n]$ is the input and $y[n]$ is the output: $$x[n]-x[n-1]=-10y[n-1]+2y[n]+2y[n+1].$$ The question asks me to compute the impulse response from this ...
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1answer
102 views

properties of System

I am studying Signals and Systems. Anyone, please help me to answer the problems. $y(t)=dx(t)/dt$ is time invariant: True or False ? $h(t)$ is the impulse response of an LTI system. If $h(t)$ is ...
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1answer
17 views

Artificial Neural Network Example Problem

I was looking at an example of a NN but I dont understand in the Answer i where the .68 come from or .6637 This is the link of the tutorial
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1answer
181 views

Question on sketching the amplitude spectrum of signals

I can't seem to understand the sketches of the amplitude spectrums provided in my tutorial solutions. For this part , I understand that X(f) is basically sampling (T/Tp)sinc(Tf). But from what I ...
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1answer
34 views

Working out integration of basic signal functions

As the title suggests , I'm having problems working out the integration of some basic signal functions. Shown below are the questions and my workings. For some reason I'm just unable to get the answer....
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1answer
65 views

What happens at the edges in fft2 filtering?

I am doing a fairly simple homework assignment in MATLAB that is to filter an image in the frequency domain. So my code looks something like this: ...
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1answer
101 views

Example exercise - Shannon's law on PCM-digitized signal

I am studying for a Digital Communications course in my university, and I am presented with the following example exercise. You have a sound signal with spectral components in the 300-3000 Hz ...
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1answer
156 views

Circular Convolution of h(n)*x(n)

So I understand how Convolution works but Circular convolution seems a bit messy to me, all the examples seems to have even series of number like h(n)={1,2,3,4} & x(n)={1,2,3,4} and they are all ...
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1answer
50 views

How to simplify this sequence

So I had this question (f) at my last exam that I failed and I'm now studying for my re-exam, the problem is that I still don't know what the answer is supposed to be in this question (f): Do you ...
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2answers
137 views

DFT and FFT application in signal processing

Can anyone give me some hints to solve this problem
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2answers
104 views

Transfer function block diagram

Can any one help with the $y[n]$ and $x[n]$ relationship in this block diagram, I just keep have a $t[n]$ in my answer that I can't get rid off. On my best try I got to $y[n] = 2t[n]-x[n-1]-y[n-2]+x[...
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1answer
113 views

Signal Processing using Fourier Transform

How can I derive the fourier transform of ...
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1answer
37 views

Impulse response of a system

I have the following difference equation: $y[n]=y[n-2]-0.25y[n-4]+x[n]-x[n-2]$ I need to find the first 6 values of the impulse response of the system characterized by that equation. When I do that, ...
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3answers
256 views

Fourier transform of triangular function

Determine $X(\omega)$. $g(t)$: I understand how to create a box from [-1,1] of amplitude 1/2. $x(t) = g(t) * g(t)$ $X(\omega) = G(\omega)G(\omega)$ the solution I am seeing says that $G(\omega) = \...
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1answer
34 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?
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1answer
135 views

How to prove that this impulse response is stable?

This is the impulse response: Can anyone give a detailed method to prove that it is stable or not ?
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135 views

What are the frequency components of a sampled signal after low-pass filtering?

A continuous signal $x_a(t)$ is a linear combination of sinusoids of frequency 250 Hz, 450 Hz, 1 kHz, 2.75 kHz and 4.05 kHz. The signal $x_a(t)$ is sampled at $f_s=$1.5 kHz, and the resulting digital ...
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0answers
127 views

MATLAB implementation Spline Fitting

Let $s(t)$ be a signal that can be approximated by a uniform spline function of order $K$ (say $K=2$): $$s(t)\approx\sum_{n\in \mathbb{Z}}c_n\beta_+^{(K)}(t-n) $$ Suppose that we know the ...
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2answers
80 views

Frequency Response Output

I'll start off by saying, yes this is a homework problem, and no I do not want the answer. I simply need to know where to start. The input to a system with a frequency response of $H(\omega)$ is $x(...
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1answer
58 views

Convolution of h(n) & x(n)

can anyone please help me with finding Convolution for following problem ..... 1) $h(n) = \delta[\sin(1 + |n|)]\quad \text{and}\quad x(n) = \sin(n^2)$ 2) $h(n) = \delta[\sin(2\pi n/N)] \quad \text{...
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1answer
67 views

Solving for impulse response

I'm working on some problems that instruct me to find the impulse response of a given system. For example $$y(n)=4y(n-1)-4y(n-2)+x(n)-x(n-1)$$ The first step I take is to find the homogeneous ...
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1answer
42 views

Discrete Time to Frequency Response

I'm learning (trying to learn) how to find a frequency response. I have a discrete time equation and want to understand the process for finding a frequency response. Ex: $$f(n) = 2\,\delta(n)-5\,\...
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1answer
358 views

Solution to Cross-correlation problem of 2 audio signals

There are 2 audio signals, X & Y. X is of 15 second duration. The duration of Y is not given. Y is a part of signal X (ie a small part of audio X is extracted & made into audio Y) I have to ...
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1answer
90 views

How to derive the answer to this convolution problem?

I came across this below question, (which was a homework assignment question for Signal Processing class, which my friend mailed me for help solving), mulled over it for an hour and had no idea how to ...
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0answers
83 views

Multiply filter kernel by sine

1)Suppose that we have low-pass filter with cf equal to 0.1. How frequency response would look like if I multiply filter kernel by sine with frequency say 0.3? How this is related to converting low-...
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2answers
293 views

Frequency spectrum of a sinc function

I am doing one example from my book as a preparation for exam. The assignment is: It is given that: $$\mathbb{rect}(t)=pf(t) \leftrightarrow PF(f)=2AT_0 \cdot \mathbb{sinc}(2\pi fT_0)$$ you ...
2
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1answer
54 views

Stability of transfer function

Now K(s) is obviously the negative feedback loop which is ${H(s) \over 1+H(s)G(s)}$ When I substitute ${H(s) = {1 \over s-2}}$ I get K(s) = ${ 1 \over s-2 +G(s) }$ For the system to be stable I ...
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0answers
17 views

Simulating rain interference

What fading model should I use for simulating rain loss in my network simulations? I am using NS-3 for this and I'm quite lost on how to go about this. My simulation is just simple packet streaming ...
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0answers
56 views

Image processing(JPEG)

write an m-file that will take the"cameraman" and produce a image quality or difference matrix for spectral selection method.The image properties are a sfollowings: For spectral selection: image1:DC ...
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2answers
79 views

Computing impulse response for system with feedback terms

I'm trying to compute the impulse response for the following system: $$ y(n) = \frac{1}{2} \left( x(n) + x(n-1) \right) + \frac{1}{2} y(n-1) $$ and am told to assume that $y(-1)=0$. My solution: ...
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1answer
242 views

Time domain signal $y(t)=\sin(50\pi t)+3\cos(60\pi t)$ [closed]

A time domain signal $y(t)=\sin(50\pi t)+3\cos(60\pi t)$ must be sampled with no amplitude ambiguity of aliasing. What minimum sampling period should be chosen to meet this goal? What is the ...
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1answer
202 views

how to find the “Natural and Total Response” of the system

Hello there I am a Student. I need to know how to find the Natural and Total Response of the given system: where: $x(t)=e^{-t}u(t)$ and $y(0^+)=2, \dfrac{d}{dt}y(0^+)=3$. (If the image above is ...