Questions tagged [signal-processing]
The signal-processing tag has no usage guidance.
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Weird beep when using audio interface
I’m experiencing this very weird beep which randomly (usually with a maximum interval of 5 minutes between occurrences) comes out when connecting my guitar to the PC through my M-AUDIO MTrack II Plus ...
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Mackie cr4-x studio monitors cutting audio when the input volume is too low
So I bought these used active studio monitors recently and use them with trs cables connected to my SSL2 audio interface. Everytime a track gets too quiet they cut the audio to a barely noticable ...
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Curious about the math portion of subjects
I am a long time civil engineer. But I am interested in learning electrical electronics engineering and lately have been teaching myself about analog electronics, signals, digital electronics... One ...
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Understanding Block Diagrams in Control Setups
Working on some automation for a Boeing 747 autopilot, I am trying to wrap my head around what sections of block diagrams like this one mean:
I understand that something is being done to the yaw rate ...
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Spike in frequency domain in a dataset recorded using electromagnetic flow meter
I am trying to measure the water velocity of a stream along a channel using an electromagnetic flow meter at a specific location and depth. When I converted the data into frequency domain as power ...
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Calculating noise floor level and SNR
I have N samples of a baseband IQ signal that I took from an SDR (Pluto) with a certain fs (BW = fs).
How can I accurately calculate the noise floor level of that signal in dBm, SNR in dB and Peak To ...
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Converting time constant to bandwidth of 1st order system
When the system is first order:
$1/(1+s\tau)$
Why is the bandwidth: $f_{-3db}=1/(2\pi \tau)$?
Where did the $2\pi$ come from? Why isn't it simply $1/\tau$? The unit of $2\pi$ is related to radian. But ...
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Maximize SNR of RGB IR light-sensor for certain LED wavelength
I have a light-to-digital sensor (TCS34001) that measures intensity in four different bands (R, G, B, IR) and a red LED (ASMT-MR00-AHJ00) that I want to detect. Their spectra look like this:
(ignore ...
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Two-Ray Ground-Reflection Model: Understanding the Difference in Phase Offsets at the Receiver
Currently, I'm trying to understand the Two-Ray Ground-Reflection Model.
During my research, I came across the following simplification expressing the received power as follows (taken from Wikipedia):
...
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155
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What is the intuitive explanation for why a system can be stable with a negative gain margin?
Beyond the math which shows that a gain of -1 and a phase of -180 (G(s)=-1)causes instability when the open-loop TF is taken to closed loop, the way I've always justified the instability of G(s)=-1 ...
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Minimizing the MSE with symmetric scalar quantizers
Let $X$ be a scalar random variable with pdf $f(x)=e^{-2|x|}$. Among the class of symmetric 3 -point scalar quantizers find one which minimizes the MSE in quantizing $X$. Compute the MSE in this case.
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How often is discrete-time control used in industry?
Although in reality I know that computers handle all systems in discrete time, in my limited industry work experience I've only used continuous-time control system analysis/standard frequency domain ...
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How to get the difference equation from second-order digital filter block diagram?
[![enter image description here][1]][1]
Here I have a diagram and I am trying to create a difference equation for the filter.
I've been using practice examples to try figure this one out however I am ...
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101
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Troubleshooting clipping
I am collecting data for a project, where I am measuring the room impulse response by playing a sine sweep from a speaker (QSC K8 1KW Active Loudspeaker) and measuring it from the other side of the ...
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How simultaneous can we trigger multiple cameras' frame acquisition
Say we have ten cameras surrounding an object. The object changes its color with a certain frequency (or any information other than color, such as a text on it). The point is if all cameras are ...
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How to select a burst frequency of an Ultrasonic sensor?
I am using an Ultrasonic sensor to detect obstacles for adas applications. Is there a way to find the optimal burst frequency? experimentally or theoretically? for object detection.
How does changing ...
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How to remove ground detections of an ultrasonic sensor place in the front bumper of car? [closed]
I am working on a project to fuse the sensor information of 4 ultrasonic sensors place on the front of a car in the bumpers. The detections from the sensor would be generated not only from the ...
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Process this output of an off-the-shelf pressure sensor
I'm a software engineer working on theoretical things in my daily work. Lately I wanted to connect a pressure sensor, like this one, to a digital device that I can program, so that I can constantly ...
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Finding a signal output $y(n)$ with input signal $x(n)$ and impulse response $h(n)$ with a DTFT
I am studying for my Digital Signal Processing course and I am stucking on the following exercise:
Given an $\text{LTI}$-system with input signal $$x(n)=\frac{1}{4^n}u(n)$$
and impulse response $$h(n)...
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What is the best way to enhance an existing LTE signal on a mountain hut?
I'm traveling to a mountain hut in Austria every year which is in the middle of nowhere. If you're lucky you can sometimes get one bar and a weak Long-Term Evolution (LTE) or Edge connection for a few ...
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How to get difference equation from this block diagram
I was posed a very similiar block diagram in my exam from this book (Alan V Oppenheim Ronald W Schafer - Discrete-Time Signal Processing-Pearson Education) but couldn't solve it:
I want to solve for
...
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857
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Calculating the transfer function of this block diagram
I'm not really sure what steps to take to solve the problem. I tried with G4 and G2 first but I'm not sure if that is the correct way.
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How do you generate an impulse signal in a mechatronic system?
Background:
I have a piezoelectric force transducer that I am using to measure the force produced by a combustion reaction in a tube. The issue is that there is a lot of ringing that occurs during the ...
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how to interpret plots in ISO 10816-8?
In ISO 10816-8 for reciprocating compressors, there are some plots that show the allowable RMS vs. frequency for every part of a compressor.
However, in the text of the standard, it is mentioned that ...
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How do mobile phones produce signals?
Normally it would require alternating currents to product electromagnetic waves. Yet as mobile phone is powered by batteries which only produces direct current, what type of mechanism/structure allows ...
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What should be the sample frequency to test the response of a filter?
I am testing the frequency response as a filter as below, what should be the sample rate of the chirp signals, someone told me it should be at least 2 times of the input signals frequency, someone ...
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155
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How do I study the frequency response of a physical system with Arduino?
I am a control engineering student and I am studying the frequency response of a system, so the Laplace domain, the Bode plot, poles, zeros,etc. ...
I have clear grasp of their meaning, but if I think ...
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Is it possible that room noises could end up on the recording when recording audio from an analogue source?
I have a VCR with a tape cartridge playing in it. The video output (SCART/RCA) goes from the back of the VCR into my Elgato video capturing device's RCA cables. The Elgato device is then connected via ...
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How to send true digital data in discrete values?
To my understanding signals in any form sent through empty space is in the form of electromagnetic waves. This implies that it is never discrete two values but it can be modulated. Looking at this ...
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How can I find the Transfer Function in Z-domain?
This is my signal;
$y[n]=x[n]+0.8x[n-0.2]$
When I take Z-transform I get;
$Y[z]=X[z]+0.8z^\frac{-1}{5}X[z])$
Then I found the Transfer function as;
$H[z]=\frac{Y[z]}{X[z]}$
$H[z]=1+0.8z^\frac{-1}{5}$
...
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Finding force distribution using accelerometer data
The team I'm currently working for is trying to compare bushings with different durometer ratings in the front suspension using single axis(z) accelerometer data during curb impacts. The current ...
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Adaptive downsampling of time-series data?
I’ve been tasked with developing software to (among other things) log temperature data from samples in a furnace. Generally the temperatures are very steady, but can, at times, experience dramatic ...
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Can cross correlation be used to see if filtering of a signal has changed it too much?
I am filtering a signal, and want to check if I am not over filtering it , I wanted to use cross correlation , but I am not sure if it is a good technique. usually I get something like the following ...
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Non-observable effect of low-pass filter on the Transfer function (of Vibration measured with Laser scanner)
I have to study the effect of low-pass filters (if any) on the outcome of the experiment. And the experiment here is to measure the vibration of a (metal) specimen by hitting the said specimen with ...
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What is the output of a signal in time domain that passed through a High Pass Filter with simple transfer function
If a signal function $ U(t) = 25 – (5 – t)^2$ is passed through a high pass filter with transfer function $\frac{s}{s + ω}$. what is the output signal Y(t). I know that the transfer function $H(s) = \...
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How does the number of cycles for averaging in a lock-in amplifier relate to low-pass filtering and where do I set it?
Please forgive me if I ask too many questions at once or I am too much of a rookie. I want to understand the working-principle of lock-in amplifiers (LIAs).
I understood the calculation that yields ...
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Shouldn't linear time-invariant systems be called affine time-invariant systems instead?
For a scalar $c$, the function:
$$f(x) = cx$$
Is linear in that it satisfies the superposition property. If:
$$f(x_1)=cx_1$$
$$f(x_2)=cx_2$$
Then:
$$\alpha f(x_1) + \beta f(x_2) = \alpha(cx_1)+\beta(...
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Arduino DAC to Speaker
I'm working with an Arduino Due's two DAC pins.
I want to output to a single 4W 5.7Ohm speaker to test my code, with the intent of eventually outputting to a set of speakers (woofer, mid-range, and ...
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How were the tones for DTMF chosen?
In my limited engineering knowledge, and limited research skills, I couldn't find a complete answer for the reasoning behind the chosen tones for DTMF. I did find a hint that said something about ...
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Signal convolution: continuous signals
I really didn't understand how to do it. Please, can anyone help me??
Determine h (t) * x (t) when h (t) and x (t) are the rectangular pulses shown in Fig. A. Plot the result of this convolution.
I ...
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Nyquist Stability Theorem and Clockwise/Counter Clockwise Encirclements
According to argument principle, if a contour encircles a number of poles and zeros of a transfer function, the number of origin encirclements can be deduced by : ...
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How do I calculate the delay of two signals from different sensors?
Suppose:
I have two sensors attached to a vehicle
I have recorded the output of these two sensors (for example GPS) during a test ride
each sensor has a different frequency
one sensor is way more ...
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In Digital Signal Processing, why is the spectrum of a signal with 'real' samples better than the spectrum of the same signal with padded samles?
Say we have number of samples to be 128 and a signal sin(2*pi*1000*n*Ts)+sin(2*pi*2000*n*Ts) sampled at 8kHz.
Now say we have same signal but only N = 64 samples. But in order to create 128 samples, ...
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Why do color TVs make black and white snow?
If you let a color TV display something from an unplugged display port, it displays snow, right? Randomly varying black or white pixels on the whole screen.
My guess was that the television was ...
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Problem with RHP zero in transfer function
I have a transfer function with a RHP zero in $s=+1$, and I am trying to show in Matlab thath this limitation is present. In particular, initially I had a MIMO system, which I decoupled and then I ...
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Fourier serie signal approximation
I have to approximate the red function with Fourier harmonics.
I am calculating complex Ck the following way.
I am not sure what to put for period - T (6 or 2pi or what?). What integral limits to ...
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Difference between Hysteresis, low pass filter and deadband in control theory?
I am trying to understand the fundamental difference between the following terms in the context of control systems:
Hysteresis
Low pass filter
Deadband
Are these just fancy names that can be ...
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How to determine data size created by sensor for calculation of signal processing and transmitting over wireless communication?
I want to build some sort of SAR sensor. Since radar works high speeds and creates loads of data this should be processed faster. I am trying to find algorithms to be used for this purpose. I am at ...
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how to filter model-free observations (e.g. Kalman filter)
Before asking a question, I have no background knowledge of engineering. So I have no idea about these issues like control or signal engineering. (Also, I'm not good at using English. sorry for that.)
...
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classify ECG signal using neural network
I am looking to classify ECG signal using with neural network. I have never done signal analysis before.
From the samples of data I have, I have noramlised, transformed using the FFT , get the pics, ...
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