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I think the answer is false but not so sure please help me [closed]

If m*n matrix is of rank n, then the right inverse of it will always exist. On the other hand, if the matrix os of rank m then the left inverse of it will always exist.
Mohit Singh's user avatar
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0 answers
15 views

Forcing function and finding response of the system [closed]

The response of the system represented by (E^2+0.1E-0.2)y(k)=4(-3)^k+(2)^k-1 to the forcing function given above will not go to infinity. True False
Mohit Singh's user avatar
5 votes
0 answers
82 views

Efficient computation of 2^x (antilog2) for fixed-point

I've created a log2 AGC for an FPGA project, similar to Dan Boschen's solution in this question. I implemented a hardware version of log2 based on Dan's linked page in the previous question - ...
WannabeDSP's user avatar
6 votes
2 answers
860 views

How to know if a continuous function can be represented by a finite sum of sinusoids?

I have a lack of mathematical knowledge, and notably in mathematical vocabulary, so maybe a similar question exists but with a different wording. What I want to know, is actually how to know if a ...
endyx's user avatar
  • 63
3 votes
1 answer
172 views

Why is there a tradeoff between simplicity of a window function and its ability to be adjustable and controllable?

While studying and applying different window functions in a project I am working on, I found that known windows (here is an example paper which cataloged numerous windows) suffer from 2 kinds of trade-...
RajaKrishnappa's user avatar
1 vote
1 answer
53 views

What is the effect of multiplication on the value of discontinuities?

I see that the values of a distribution at discontinuities are essentialy equal to the mean of the right-hand and left-hand limit values when dealing with distributions in relation to the Fourier ...
Finn Heijink's user avatar
0 votes
1 answer
82 views

How to handle undefined functions in a convolution?

When convolving with undefined functions, do we just treat them like variables? (eg. How do I handle $u \left( k \right)$ and $u \left( n - k \right)$ since they are just step functions with no ...
Axel's user avatar
  • 3
0 votes
0 answers
13 views

How to handle imaginary numbers with total square error questions

I am pretty new to algrebra so if u can use simple terms and explain a bit more it would be helpfull. Ive been trying to use imaginary numbers to get the total square error of a graph of a non linear ...
Joziah's user avatar
  • 1
0 votes
1 answer
77 views

Improving Modeling of Thermal Noise Behavior at Antenna

Background I recently asked this question over on Electrical Engineering Stack Exchange. On the advice of some commenters there, I've broken off those pieces which are appropriate for asking as ...
MomentumEigenstate's user avatar
0 votes
1 answer
30 views

Improving Modeling of Thermal Noise Propagation Through a Signal Chain

Background I recently asked this question over on Electrical Engineering Stack Exchange. On the advice of some commenters there, I've broken off those pieces which are appropriate for asking as ...
MomentumEigenstate's user avatar
3 votes
1 answer
289 views

How can I show that an LTI system can be expressed as a difference equation?

I'm in the process of re-learning DSP (not a subject I've visited since University) and in quite a few resources I see this general form of a DT-LTI difference equation: $$y[n] + a_1y[n-1] + a_2y[n-2] ...
andowt's user avatar
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0 votes
0 answers
35 views

Verifying Linearity and Shift Invariance Under Summation

I am having some trouble working through verifying linearity and shift invariance when the transformation is under a summation. The given transformation is as follows: $$ y(m,n)=\sum_{i=-1}^{i=1}\sum_{...
pflykyle's user avatar
2 votes
0 answers
214 views

Ambiguity function volume

I find myself confused how two properties of the ambiguity function relate to one another. The properties in question are (presented here from wikipedia, but similar formulas can be found in books by ...
Narrava's user avatar
  • 21
6 votes
5 answers
2k views

Under what conditions does DFT(f(x)) = f(DFT(x)) hold?

I have encountered a text (a specification) in which $$\text{FFT}\left(f\left(x\right)\right) = f\left(\text{FFT}\left(x\right)\right)$$ is clearly presumed (for the functions they are applying). Thus,...
Bernd Wechner's user avatar
2 votes
1 answer
1k views

Time shifting a signal in python

I am currently modeling FMCW (linear FM) and SFCW (stepped FM) chirps in python. For my project, I need to simulate those signals as a transmit chirp and a received one, scattered from point targets ...
Lucas's user avatar
  • 65
6 votes
1 answer
282 views

Pole Quantization Patterns in 2nd Order IIR Resonators

Background My typical approach to fixed point design for digital filters is to iteratively scale and increase quantization while comparing the fixed point simulation to the floating point design ...
Dan Boschen's user avatar
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0 votes
1 answer
42 views

Fourier transform why can I convert one of the axes into an imaginary number?

Contextualizing This question is inspired by the following video: https://www.youtube.com/watch?v=-qgreAUpPwM&t=60s&ab_channel=3Blue1Brown I own a sign, a drawing of a square with 200 points ...
rafaelcb21's user avatar
4 votes
3 answers
2k views

Why Hilbert Transform is terrible choice for amplitude demodulation of broadband signals?

A reference answer empirically demonstrates that Hilbert envelope does not work well for the (amplitude) demodulation of a broadband signal. I am looking for the math which explains why...
Gideon Genadi Kogan's user avatar
0 votes
2 answers
417 views

Get IMU acceleration of a direction when tilted

I have an IMU that is placed on the body. My goal is to calculate the position data of the vertical upward movement. Since the sensor is never perfectly aligned and will always have a little tilt, I ...
Malte's user avatar
  • 1
0 votes
0 answers
52 views

Confusion Understanding the mathematical expression of duality property of dft?

Duality Property for DFT Above dsp.se question provides good understanding about dft duality property but i am having difficulty understanding its mathematical expression because on Google when i try ...
DSP_CS's user avatar
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5 votes
2 answers
450 views

What *is* pitch-shift?

As I understand it, pitch-shifting (without changing speed) and time-scaling (without changing pitch) are two sides of the same coin, because if we can do one we can get the other through resampling ...
orlp's user avatar
  • 151
1 vote
2 answers
1k views

How to Get Started On Demodulating Signals Such As Amplitude Modulation and Pulse Width Modulation

I'm looking to understand how signal modulation/demodulation works. My goal is to be able to demodulate a 315 MHz key fob and be able to tell what buttons are being pressed so I can have a Python ...
Alexis Evelyn's user avatar
6 votes
1 answer
342 views

How to Find the Kernel of the Convolution for Linear Interpolation?

I'm trying to solve the following exercise: Image A was doubled by linear interpolation. The magnification was performed in two stages. In the first stage, add about zero pixel to the image between ...
vesii's user avatar
  • 293
-1 votes
1 answer
95 views

I'm having problems simplifying this discrete-time fourier tranform

I have this problem, and I can't get to the solution. $$X(e^{j\omega}) = \sum_{n=-\infty}^{\infty} {(0.6)^{|n|}[u(n + 10) − u(n − 11)]}e^{-j\omega n}$$ The solution is $$X(e^{j\omega}) = \frac{0.64 − ...
Derteck pt's user avatar
0 votes
1 answer
628 views

How do I carry out SRT Radix-4 fixed-point division with more than a few bits?

I've managed to get a hand on how SRT division works, but I haven't been able to construct a working example. My current sticking point is that e.g. the Pentium floating-point division bug came about ...
John Moser's user avatar
-2 votes
1 answer
37 views

what are the application of fourier transform in finding frequency response? [duplicate]

i need the application of Fourier transform in finding frequency response in mathematical terms
swetha's user avatar
  • 1
3 votes
1 answer
184 views

Is it possible to compute the PSD of s(t)^2 given the PSD of s(t)?

Given a well-behaved signal $s(t)$ given by, $s(t) = \sum_{i}^{N} \cos( \omega_it + \phi_i) $ with a large $N$ and a well-known power spectral density (PSD), $\tilde{S_1}(\omega)$. Is it possible to ...
Gyromagnetic's user avatar
1 vote
1 answer
645 views

False positive rate with CRC

What is the technique to calculate the false positive rate for an N-bit CRC? Example: Communication system sends M-bit packets with a N-bit CRC (M >> N) appended to each packet. What is the ...
BigBrownBear00's user avatar
0 votes
0 answers
80 views

Problem with the output self implemented “ Iterative FFT DIT Radix2 ” algorithm matlab

I´m trying to implement my own FFT with the iterative Radix2 algorithm (I even thought about using the recursive one but it seems Simulink doesn´t allow me to). I tried all of the possible variations ...
Meo PBK's user avatar
1 vote
2 answers
265 views

Parseval's Theorem for Time Domain Data with DC

I have read several times that the variance for time domain data with a zero mean is equal to the integral of the power spectral density divided by N. From wikipedia, the discrete form of Parseval's ...
FooAnon's user avatar
  • 296
0 votes
1 answer
52 views

Different mathematical signal models for different applications

I am looking for some interesting and physically meaningful applications of different signal models. I am currently working with complex analytic signal model given below, but I couldn't come up with ...
Neuling's user avatar
  • 103
1 vote
0 answers
21 views

Backpropagation in a Network [closed]

Hi does anyone know how to solve this. Im really struggling to figuring this one out. I am unclear of how the backpropagation part would work in this network and how to calculate it for each weight. ...
get3low's user avatar
  • 23
1 vote
1 answer
307 views

Calculating Haar features

I am confused on how to solve this problem, does anyone have any ideas? https://www.merl.com/publications/docs/TR2004-043.pdf For a Haar filter $H \in \mathbb{R}^{3 \times 5}$ defined as below: What ...
get3low's user avatar
  • 23
2 votes
1 answer
855 views

Digital integrator

I have been implementing a control software where I need to calculate a magnetic flux based on the measurement of the phase voltages of a three phase grid (basically three sinewaves) according to the ...
Steve's user avatar
  • 395
1 vote
3 answers
209 views

Question about delayed sampled sinusoid math expression

I have been studying the digital audio processing by using the book <Designing Audio Effect Plugins in C++>. For analog Sinusoid: Complex Sinusoid = $e^{jωt}$ Delayed Sinusoid = $e^{jω(t−n)} = e^...
Hao Wu's user avatar
  • 31
6 votes
1 answer
189 views

Why Does the Median Filter Minimize the Absolute Value Error $L_1$ Cost Function?

I can easily prove that the mean filter minimizes the square error $L_2$ cost function using simple calculus. However, how do you prove that the median filter is optimal with respect the absolute ...
Izzo's user avatar
  • 862
0 votes
1 answer
52 views

mathematical expression to detect modulated data within a vector

Assume I have such modulated data which is, for example, $x=0.7+0.7i$. That modulated data is encapsulated in a vector as below: OR where $c$ is any constant number, let’s say, for example: $c=0.7$ ...
Fatima_Ali's user avatar
1 vote
1 answer
58 views

Effectively extracting “real” data from a noisy dataset

This question was originally posed to Math SE. It was suggested that DSP SE would be more suitable. Background & Motivation: I have three lists of timestamps (UNIX timestamps, plus a subsecond ...
10GeV's user avatar
  • 123
0 votes
0 answers
32 views

Is it important to learn to find de period of the sum fo two DT signals?

The fundamental period (N) of the sum of two DT signals could be the LCM of the fundamental periods. However, this is not always the case. I would like to know wether, during engineering design or ...
Daniel Melo Avila's user avatar
0 votes
0 answers
48 views

When is Markov a Martingale

I have two questions and I am very confused about the concepts Can a Markov process of order one also be a a Martingale? Is any Markov process of order one also a Martingale? For 1. I would say yes, ...
gkc's user avatar
  • 1
1 vote
1 answer
230 views

The Math of Histogram Matching

Please help solve the problem in the picture. I am confused due to the piecewise nature of the density functions. If it was a simple curved PDF, I would simply integrate over full range and use the ...
fac120's user avatar
  • 11
1 vote
2 answers
655 views

Problems computing the DFT of finite length sequence

I am having trouble finding the same answer as the solution manual for this sequence. The problem asks to compute the DFT of $$ x[n] = \begin{cases} 1 & \text{for even } n \in \{0\...
scott's user avatar
  • 113
1 vote
1 answer
439 views

Linear correlation of two vectors?

We had a lecture on digital watermark detection using linear correlation. Here it was explained that the linear correlation of two vectors is equal to their scalar product divided by the dimension. So,...
Marcel Herbst's user avatar
0 votes
1 answer
147 views

Relation between the matrix trace and the amplitude of each element

Assume a diagonal matrix $\mathbf X$ whose size $N\times N$ and its diagonal elements are $0.5 + 0.5i$, and the vector $\mathbf p$ of size $N\times 1$ whose elements have similar amplitude. I have ...
New_student's user avatar
2 votes
2 answers
3k views

DFT of pure sinusoidal wave

I'm writing a program in which you can synthesize waves by adding to a sound's Fourier transform, and then inverse the transform to get the modified sound. In order to do this, I need to know what to ...
Verpous's user avatar
  • 121
2 votes
1 answer
395 views

SNR for the magnitude of a complex signal

The SNR for a complex valued signal is presented by Dilip Sarwate in: https://dsp.stackexchange.com/a/42359 Following the same steps I would like to estimate the SNR for the magnitude of a complex ...
MrG's user avatar
  • 23
0 votes
1 answer
42 views

I don't understand how the zeros are found of this 2nd order feed-forward filter

I realized someone asked a question about the exact same section of a book, which can be found here: Question about zeroes of simple 2nd order FIR filter. While the answer to this question looks ...
Steve M's user avatar
  • 101
2 votes
2 answers
2k views

Coordinate system in digital image processing

I am trying to understand image coordinate system where I read that it is reversed. So if $f(x,y)$ is actually $f(y,x)$ where $f(\cdot, \cdot)$ is the image. I am a bit confused and would appreciate ...
Sm1's user avatar
  • 291
1 vote
1 answer
251 views

Summations in Z-Transform

I'm currently working on a problem that involves a Z-Transform. Basically, the essence of the problem is that if: \begin{equation} H\left(z\right) = \sum_{n=0}^{N-1}h\left(n\right)z^{-n} \end{equation}...
JordenSH's user avatar
  • 303
0 votes
1 answer
307 views

Adding attenuations in dB

I am writing a synthesizer. One part of the synthesizer specification says that different sources can specify an attenuation to be applied to a signal, and that these attenuations should be summed. ...
user19642323's user avatar