Questions tagged [signal-analysis]
The signal-analysis tag has no usage guidance.
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11 views
Unknown encoding with some known parameters
I have a encoded hex values of 3 cipher text(encoded) and corresponding length of plain text too.
The plain text and cipher(encoded) text is different in length.
I also have some bytes of known Plain ...
0
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1answer
46 views
Difference between two sine generators
I have two sine oscillators and I get these two different spectrum analysis (let's disregard the slight frequency difference). Is there any deductions that can be made about the "quality", or sine ...
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0answers
12 views
Log Sine Sweep Acoustic Measurements
I am currently trying to understand the Sine Sweep Method for taking acoustic measurements.
I am following this paper:
https://www.thinksrs.com/downloads/pdfs/applicationnotes/SR1_SweptSine.pdf
I ...
0
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1answer
24 views
Are the error probability of orthogonal signal and on/off signal the same?
I have to write the error probability of orthogonal signal and on/off signal,and now i have finished the error probability of on/off signal,but i don't know how to write the code about error ...
1
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1answer
49 views
Calculation of line of sight system gain
I'm trying to calculate the overall gain of the transmitter-receiver system for a line-of-sight wireless transmission with the following properties:
A carrier frequency of 0.5GHz
A distance between ...
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0answers
15 views
How to find the filter coefficient of matched filter to detect the pulse of a signal?
I would to understand how to find the coefficient of a matched filter.
Let's consider we have a signal and the signal is buried in the following noise. we want to find the coefficient of a matched ...
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3answers
70 views
What is the precise definition of a nonlinear signal?
I tried to find the the precise definition of a nonlinear signal. However it is not easy. How can we define a nonlinear signal?
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0answers
7 views
Looking to simulate sound level meter (read microphone audio signal into 1/3 octave)
I am looking to pull audio from a microphone and analyse the 1/3 octave data. Can anyone suggest a software library to do this that I could then build a software interface on top of? Initially looking ...
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0answers
17 views
How can one calculate a signal-to-noise ratio between two spectrograms in Python?
For context, I am creating a Python program for speech de-noising / enhancement. I am doing so by first taking a clean speech recording, mixing it with a noisy signal, and using a model to estimate a ...
2
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0answers
37 views
Multiply signal $x[k]$ with $\cos(2\pi\nu_0k)$, then given $X(\nu)$ draw resulting function in frequency domain?
Let
$$y[k]=x[k]\cdot \cos(2\pi\nu_0k) .\tag{1}$$
Then, given a signal $x[k]$ with the DTFT $X(\nu)$ according to the following figure
what will the frequency domain for $Y(\nu)$ look like for a ...
2
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2answers
42 views
Contradiction while using the convolution sum for a non-LTI system
In a recent quiz, we were given the following problem:
The cascaded LTI systems $\mathcal{T}_1$ and $\mathcal{T}_2$ respectively have impulse responses $h_1[n]=\delta[n+3]$ and $h_2[n]=\delta[5−n]$....
1
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1answer
27 views
How do bode plots work with unstable systems work?
If I had a system with right-half s-plane poles, how would a frequency response work? Since a purely imaginary value for s, would cause the Laplace transform to diverge for such a system, what meaning ...
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3answers
59 views
Significance of signal energy in audio?
Probably a dumb question but I can't find the answer anywhere. It seems to me that the energy carried by a sound wave should be proportional to frequency squared. For example, the waves $x(t)=\sin(t)$,...
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0answers
10 views
Analysis of linear acceleration and angular velocity, how to?
Excuse me If you don't feel that this question is good enough, but at the moment this is my level of entry knowledge.
Imagine that you have 200 recordings from the sensors, and information that you ...
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0answers
14 views
Signal ECG Noise correction
in order to make the correction of an ECG signal full of collector noises from a sensor, I use the fast Fourier transform (FFT) method and it sends me complex numbers, my problem is that I do not know ...
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1answer
32 views
Frequency estimates from three-dimensional data
I have a lot of three-dimensional positional data from patients with tremor, unevenly sampled at approx. 50 Hz, with timestamps. I am trying to find the dominant frequencies in the signal/tremor. ...
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0answers
26 views
I want to plot a gaussian pulse in MATLAB in the frequency domain, with its centre at the highest value
I have tried one way but i am getting 2 peaks at the edges as shown in the picture. I have used 1 part of my code for the signal generation where i used the gauspuls command (reference: www.simsonic....
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0answers
16 views
Signal ECG , collecte & visualize data
I am currently working on a sensor that visualizes an ECG signal and visualizes its data. Its principle is that it has 3 electrodes that must be placed in specific parts of the body .... I would like ...
0
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1answer
63 views
Term for integral multiples of fundamental period?
As we know that a signal has fundamental frequency and integral multiples of fundamental frequency are known as harmonics
I am curious about the term that will be used for integral multiples of ...
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1answer
16 views
Higher side lobe levels in linear array beam pattern
I am working on beam forming of high frequency (>400 KHz) linear array for imaging sonar. I have gathered sensor data of 80 channel linear array sub merged halfway in 8 m deep water tank with a ...
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0answers
37 views
Why does power spectral density of OFDM signal changes with number of zero subcarriers
I am trying to plot the power spectral density (PSD) of an OFDM signal with $N_{dsc}$ subcarriers and $N_{zeros} = N_{fft}-N_{dsc}$ zero subcarriers.
I am using the matlab function pwelch() to plot ...
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1answer
26 views
Please help me understand this paper about Discrete Wavelet Transform!
I am trying to understand this paper says.
I have found this paragraph to be vague:
(a) Preprocessing Stage. The first step in this stage was to apply the
Discrete Wavelet Transform (DWT). This ...
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0answers
39 views
processing a very noisy signal
I work on an ECG signal that I collect from a sensor, and it is very noisy. Having researched it above I read that FFT or so Nyquist-Shawon's casting theories were advised, being novice in the field ...
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2answers
159 views
Removing step-function like noise from signal, knowing when the step functions occur
So I currently have a system which is fit for very short time measurements. Whenever a measurement is long, however, there is a need to continuously update the reference, which, each time, will ...
1
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1answer
27 views
Similarity in signal plots but dissimilarity in sensed content
I have two audio signals that look incredibly similar when plotted. However, when I play them, they sound quite different. The only difference I can even see in their plots is that one signal looks ...
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0answers
36 views
Drawbacks of kalman filter
What are the drawbacks of kalman for attitude angels estimation...or what are advantages of mahony filter over kalman filter for attitude angels estimation?
2
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0answers
21 views
How to remove varying noise from strain data in MATLAB
I'm very new to signal processing. I have some data measured over time at 800 Hz. I'm interested in the high frequency signals. You can easily identify them in the image below (in this case, 3 signals)...
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1answer
34 views
Rms of a random signal
How can the root-mean-square of a random signal be calculated? The signal has a nonzero mean value.
0
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0answers
56 views
How enhance amplitude of audio signal without distortion?
After FFT I've set to zero some frequencies and I'd like to enhance the amplitude in order to recover the leak.
I'd like to do a normalization in order to avoid distortion.
I've done in this way but ...
1
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1answer
73 views
Moving average filter for sound in MATLAB
y[n] = b0x[n] +b1x[n-1]
I have this MA filter in matlab as following
...
2
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2answers
42 views
How to identify the beginning and the end of a signal using MATLAB
I have multiple signals as shown in this image. I'd like automatically detect time for the earliest detection of the signal (approx 0.7e4 in S1-B3-B (orange)) and last detected occurrence of the ...
0
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1answer
36 views
Area under waveform in t-domain including 2 delta functions
question:
my attempt:
$(a)$ $\displaystyle\int_{-\infty}^{\infty} f(t) dt=2 u (t)+r(t)-r(t-T)+Ku(t-T)$
then we draw it's diagram and found it was unbounded so,we doubt how area can be zero for any ...
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2answers
47 views
Alignment of 2 Set of Samples from Different Sensors
If we measure the heart rate of a subject with two different devices, which have big different sampling rates then how we can compare their outcomes. For instance, one of the devices has the sampling ...
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0answers
20 views
Impulse response of discrete time system
I am learning about discrete systems and in this derivation something struck me as quite odd. Solving for $A_0$ in this equation seems dubious as it ignored all other values of $n$. For example, at $n=...
0
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1answer
28 views
Processing using Matlab
I'm new to Matlab.As a beginner, I want to work on few signals which are used in day today life and extract useful information through it. Can someone please help me from where I could start or share ...
2
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2answers
50 views
Significance of modular arithmetic in DFT?
In what ways does modular arithmetic plays a part in DFT?
Why is it a so integral part of DFT?
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0answers
36 views
Is it possible to analyze this microphone data and what to do if not?
I just created an account here because I really need some help. I'm using a microphone pmodmic3 with a development board called Ublox C030-U201 which uses the mbed OS. The microphone is working for ...
0
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1answer
43 views
GPS Code Phase usage
During Cross-correlation process:
xcorr=ifft(fft(a)fft(b)∗)
we have frequency offset and code phase offset.
How is it used later in the process of finding a ...
2
votes
1answer
75 views
Frequency estimation on chaotic waveform
The target signal is generated by the following analytically solvable hybrid chaotic oscillator
\begin{equation}\label{eq:1}
\ddot{u} - 2\beta \dot{u} +(\omega^2+\beta^2)(u-s)=0
\end{equation}
...
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2answers
32 views
Rayleigh energy equation - applied to Fourier Transform of a sinusoid
I saw details indicating "total energy of a Fourier-transformable signal equals the total area under the curve of squared amplitude spectrum of this signal."
I have no issue with that. But I have ...
2
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2answers
52 views
Periodicity of sum of discrete signals
In my lecture slides for school and from this website here
"The sum $z[n] = x[n] + y[n]$ of periodic signals $x[n]$ with fundamental period $N1$, and $y[n]$ with fundamental period $N2$ is periodic ...
0
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1answer
40 views
Basic question regarding third octave filters
I would like to use third octave filters on a time signal.
Do I have to apply all third octave filters to a single frequency or do I only need to apply the one that has its center frequency the ...
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0answers
21 views
histogram bin size vs. data sampling rate
I have a set of numerical signals that give me a set of zeros calculated based on some numerical procedure. I make a histogram of those zeros.
Here, a following problem arises:
If the histogram ...
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0answers
18 views
Help to create basic sound compressor in sigmastudio
I need create own mono compressor in Sigmastudio from basic blocks. It will be only hard knee. For RMS level I want use RMS detector.
I need set only next parameters over SPI:
- Threeshold (0-90 dB)
-...
0
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0answers
36 views
Please explain Multiplication property in Z transform?
I am having problem visualizing contour any example will be great help.
As far as as where I need it I was trying to find Z transform of a contracted signal by first multiplication by impulse train.
0
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1answer
21 views
How to detect the maximum resolvable spatial frequency of camera?
I am trying to calculate the minimum line pixel width that can be distinguished from noise as shown in the camera test chart in Figure 1 where the thinner lines on the left are getting more and more ...
0
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0answers
35 views
Interpreting Auto correlation results
I used xcorr function in Matlab to compute the autocorrelation of my signal. I obtained a graph, which is shown below. How to interpret this? I read that autocorrelation helps in finding the patterns ...
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0answers
49 views
Working principal of MIMO(2 by 2)-OFDM (802.11n)
I have gained basic knowledge on MIMO-OFDM from online sources and in process of building 802.11n standard in GnuRadio+USRP B210. My goal is to analyze the channel state information and play with it ...
0
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0answers
36 views
How to low pass very few samples
I'm asking myself what is the best way to low pass a signal which only has a few hundred samples? Or is there a proper way at all?
It must not be a sound signal but I used Audacity to display the ...
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0answers
64 views
About the variance of the white noise process
I saw such an example in a book. Assume that the $w(t)$ is a white Gaussian noise with zero-mean and power spectrum density $N_0/2$. Now, consider the sample function:
$$n(t)=\sqrt{2\over T}\int_{...
