Questions tagged [homework]
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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Signal to Quantization noise problem
a full scale signal of bandwidth 5 khz is sampled by an 10-bit ADC at a sampling rate of 2 Msa/sec
calculate the Signal to Quantization noise of the resulting DT signal
repeat for a 14-bit ADC at ...
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How can I obtain the response signal for this question?
In particular I am having trouble with 6b).
From what I understand, we can split a difference LTI equation into two sums, the sum of the previous responses, and the sum of the previous inputs.
...
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Fourier Series representation of a signal
Use the defining equation for the Fourier Series coefficients to evaluate the Fourier Series representation of the following signal:
$$x(t)=\sum_{m=-\infty}^{+\infty}=(\delta(t-m/3)+\delta(t-2m/3))$$...
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ROC and impulse response
For the LTI system given below, there are three regions of convergence.
$$H(z)=\frac{5-3z^{-1}}{1-\frac53z^{-1}-\frac23z^{-2}}$$
a) Find all possible regions of convergence for this filter.
b) For ...
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To find the filter Co-efficients of the following equation
Given $y[n]=h_1[n]x[n]+h_2[n]x[n-1]+h_3[n]x[n-2]$ is an LTI system with unity gain at $\omega =0$ and zero gain at $\omega =\pi$. $h[n]\neq0$ .Also given that the system has a linear phase. Compute
$...
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Finite impulse response FIR filters
If H(Z) is linear phase FIR filter, then what can 1/H(Z) represent?
Can it be causal and stable?
Can it be stable if it is not required to be causal?
I think it represents non linear phase FIR
...
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Sampling period
The signal $x(t)=e^{-t^2}\text{sinc}(t)$ was sampled at interval $T$. It was then found that the discrete time Fourier transform of the sampled signal is: $X(e^{j\omega})=1$. What is the minimum $T$ ...
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Derive DFT of $x((n+1)/2)$
If $X(k)$ is the $N$-point DFT of $x(n)$, and
$y(n)= x\left(\frac {n+1}{2}\right)$ for odd $n$, and $0$ for even $n$.
What is the $2N$ point DFT of $y(n)$ in terms of $X(k)$?
So far, I've ...
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Which of these signals have same Nyquist rate as $x(t)$?
The options are:
$x^2(t)$
$x(2t)$
Time derivative of $x(t)$
Convolution of $x(t)$ with itself
I guess, the Nyquist rate remains the same as long as bandwidth of $X(w)$ remains the same, as Nyquist ...
user45317
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Recovering a signal after filtering
A signal $x[n]$ is to be transmitted over a communication channel. The communication channel is described by an FIR filter of length $M$ such that the received signal
is given by
$$r[n]=\sum_{k=0}^...
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Determine the Given system is linear or nonlinear [closed]
Does the following define a linear or nonlinear system?
$$ y(n) -4 y(n)y(2n)=x(n) $$
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Calculating the number of MACs in a system
I want to calculate the number of MACs. I am looking for the method.
How would I do it if I know the domain equations from a biquadratic digital filter. I have already calculated the Z domain ...
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Computing response of LTI system in terms of its step response
I have solved a problem, Kindly help me in determing if I solved it correctly.
I will post the question and my own working below.
Problem
My working
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How to prove a filter has linear phase response?
I have designed an FIR filter to have linear phase response using odd-symmetry design. The coefficients of this filter are {2,1,3,1,0,-1,-3,-1,-2}. I am now being asked to prove it has linear phase ...
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Question About Sampling White Noise
Assuming that we have a continuous signal $v(t)$
$$v(t) = \int_0^t g(u)\, \mathrm du\tag1$$
where $g(t)$ is white noise.Then take the derivative of it.
$$\frac{\mathrm d}{\,\mathrm dt} v(t) = g(t)\...
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Equivalence of difference equation with system of difference equations
I have this system and tried to write down its difference equation as follows
$$ y[n] = b_0v[n] + b_1v[n-1]\\
v[n] = x[n] - a_1v[n-1] $$
I was asked to prove that the system can be ...
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Consider the integrator and check for time invariance
I'm trying to check the following system for for time-invariance.
$$ y(t) = \int_0^t x(\lambda) d\lambda$$
Please explain me why it is time-invariant.
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Extract approximation and detail coefficients
I am a student and would like to know how to extract the approximation and detail coefficients (A5, D5, D4, D3, D2 and D1) after an applied DWT decomposition dB5 (Daubechies 5, level = 5)?
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Inverse Fourier Transform From Plots (2019 edition) [closed]
Hello I borrowed the title for another post.
I cannot figure out how to find the inverse fourier transform from this spectrum.
I know what the transform is
I'm sorry for the plot being hard to ...
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QAM constellation coder - transmitting a file
The file with size 6 MB is transmitted in 100 seconds using a constellation coder QAM with a constellation of 6 bit/symbol
$ { M = 10^6, B = 8} $
Tasks:
1. What is the signal bandwidth if the band ...
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OFDM modulator: Transmission time calculation
I have a problem with a certain task.
The frequency of the signal sampling at the OFDM modulator output is
20 MHz. The length of the protection period is 2 microseconds and it is
20% of the ...
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659
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Amplitude and Phase spectrum of a signal [closed]
Please help me to solve this question.
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2
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145
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Is this calculation of inverse z-transform proper
I wonder whether my calculation of inverse z transform are correct. My IIR system is described as follows in Z-domain $H(z) = \frac{z^{-2}}{1-0.5z^{-2}}$
After using partial fraction decomposition I ...
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Inverse z-transform. Where is mistake?
I've already wrote about that trouble (link here), but I don't understand where I've made a mistake.
Full description of the task is as follows:
Z-transform of sequence {x(k)} describe by the ...
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1
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362
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Trouble with inverse Z-transform and calculating of samples
I have a little problem. I have to solve this task but I can't.
Z-transform of sequence $\{x(k)\}$ describe by the formula:
$$X(z) = \frac{2.5 -3.15z^{-1} + 1.2 z^{-2}}{1-2.3z^{-1} + 1.2z^{-2}}$$
...
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Sketch the following Signal: $x(t)=3\sin(\frac{\pi t}{4})$ [closed]
I feel kind of overwhelmed by it, and would like someone to walk me through the steps of sketching the signal.
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How do I know what is causing the noise in my signal
I have a noisy audio file, available here (It is safe to download if you wish to)
https://ufile.io/pstrt
Now, I inspect it in matlab:
And then i plot it on normalised frequency:
Now I need to ...
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Implementing echo on adsp 21262 [closed]
I'm working on an echo implementation on the board adsp 21262. I've added a buffer to have more samples to work with. I end up then with 4 buffers of size 2048 each.
The problem is that I need to ...
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How to calculate the magnitude of rounding error in N-bit signed fixed-point arithmetic?
In example take into consideration 11-bit <11,5> signed fixed-point arithmetic.
000000.11111 - 0.96875
000001.00000 - 1
so the error magnitude will ...
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Transfer function: from poles and zeros to polynomial coefficients
I understand how this transfer function was solved except I don't know how to get the 0.87.
Any help would be appreciated.
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Using Fast Fourier Transform to determine musical notes
Hi guys i am doing a course in Digital Filters and Spectral analysis. We are given a coursework/homework, and I have absolutely no idea what to do with it. I come from Maths background, never done any ...
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Solving the PDE of a signal in an optical fiber
Disclaimer Please let me know if this is not the right place to ask this question.
Disclaimer Part 2 I have no background in signals. My focus is in mathematics.
In my programming class, we are ...
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3
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Calculating N-point DFT of a signal based on another signal's DFT
Recently I have asked this answer.
Now I would like to know a little bit more about expressing N-point DFT's of signals in terms of one another.
Having N-point DFT X(k) of a certain signal x(n), ...
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State space equations
I am stuck on this exercise. I don't know how to deal with this squared y in the denominator. What am I supposed to do to obtain state space equations?
ex.1
Simplified dynamic model of the steel ball ...
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Determine whether the system is linear?
$T(x[n]) = ax[n] + b$
$ T(\alpha_{1}x_{1}[n] + \alpha_{2}x_{2}[n]) = \alpha_{1}ax_{1}[n]+ \alpha_{2}ax_{2} [n] +b $
$ \alpha_{1}T(x_{1}[n] ) + \alpha_{2}T(x_{2}[n]) = \alpha_{1}(ax[n]+b) + \alpha_{...
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Block diagram of filter
Can you help me with this question. Can you explain where i should start to solve the problem.
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Difference between causality and memorylessness
I have found the particular definitions.
Causality means that the output of the system does not depend on future inputs, but only on past input.
Memory-less - does not depend on previous values of ...
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Calculating an output of a system (Z- transform question)
I have a following question to answer:
An LTI system is described by its impulse response h[n]. For input x[n] it gives output y[n].
$$h[n] = u(n) - u(n-N) $$
$$x[n] = u(n) - u(n-M)$$
I want to ...
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Expressing 2N point DFT in terms of N point DFT
I have a problem with expressing odd samples of X2 in terms of X1. I understand that the resulting DFT will be more precise in terms of expressing the exact spectrum of signal x[n], due to more ...
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partial fractions expansion inverse Z-transform, help
I have the correct solution from teacher's solution guide, but I was slightly confused by some algebra about the partial fractions expansion evidently
difference equation is as follows
$ y[n] = \...
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How to find period of signal, when spectrum is known?
Here is signal in frequency domain .Division of frequencies does not give an integer number or real number. May it can be here another method of finding period for ths signal.
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solving recurrence relation with Z-transform (LTI and causal)
I just wanted to doublecheck answers for my sanity's sake (exam next week)
problem statement
recurrence relation, solve it
$y[n+1]= 35 + y[n]*0.5$
according to my teacher it will be such that the ...
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finding inverse Z transform with usage of tables (LTI and causal sequences)
problem is as follows
try to find the inverse Z
$Z^{-1} (\frac{3}{z+2}) = ???$
with the usage of z-transform tables
Ok, so in order to find something from the table, I thought that we expand with ...
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difference equation block diagram delay or advance confusion
When does the unit delay, become unit advance essentially.
Goal is to deduce difference equation from block diagram.
Green text is notes about what the value should be in that node of the diagram.
It ...
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1
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How to represent impulse function in 2D?
To be more specific I want to show that impulse function in 2D can be represented as $β(r)=δ(r)/πr$.
Also I want to show that each projection of a two dimensional impulse function at the origin is a ...
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What reference power should I use?
My professor asked me to convert following powers into decibels:
15W, 25W, 33W, 450mW, 24MW, 44 GW,120pW.
I know that decibels are about ratio power/reference_power.
I don't have reference power ...
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DFT as an Orthogonal Basis Change
In one of the homeworks that I am dealing with for Linear Systems course, I have encountered with such a statement: Consider $\mathbb{C}^N$ the vector space of N dimensional complex vectors. We can ...
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Steady state value of a complex convolution
I am trying few problems on the introductory part of DSP. One of the problem asks to calculate the steady state response of a system with impulse response $h[n] = (\frac{j}{2})^{n} u[n] $ to an input ...
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classify the system if it's linear , non-linear , time variants or invariants [closed]
classify the system if it's linear , non-linear , time variants or invariants
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Finding the transfer function of a discrete signal described by two equations
A discrete time system is described by the following system of equations.
$$q[n] = \big(x[n]-\frac k4q[n-1]\big)$$
$$y[n] = \big(q[n]-\frac k3q[n-1]\big)$$
Find the systen function and then find the ...
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