Questions tagged [signal]
The signal tag has no usage guidance.
36
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FPV for drone setup recommendation
Looking for recommendations of hardware for setting up FPV with recording with off the shelf components.
Requirements: Receive 1080p video feed on the receiver side, and at the same time record the ...
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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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How to pick transducers for an ultrasonic flow meter?
I am designing a flow meter with a team of students for a university project based on the time of flight principal. We are striving for a high accuracy. We are currently researching different ...
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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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How to send a TTL trigger signal remotely
Sorry if this is a dumb question, but I am an undergrad intern working on a semi-independent project in a lab, and no one here can really help me with this.
I am trying to control a lab instrument ...
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When working with generic electrically shielded signal cable, can I treat the unshielded strands of wire as signal reference ground?
I am working on a CNC application where one controller board will be sending signals to another board. The environment may have electromagnetic interference (EMI) from nearby motor activity, so these ...
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How significant is signal noise from a BNC connector?
I'm trying to build a double cross antenna that can be folded/taken apart based on the design of the picture and receive signals from weather satellites. The idea is to make each of the four dipoles ...
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Active noise cancelling headphones - How fast does a digital signal processor have to be to perfectly cancel out noise with an inverted signal?
How fast does a digital signal processor have to be to perfectly cancel out noise with an inverted signal? Is it possible for a digital signal processor react so fast?
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How to add a Gaussian noise signal with zero-mean in a given data set?
I have a real-time velocity measurement data set in a excel (.xlsx) file. I want to add the Gaussian noise signal with zero mean in this real-time data to create three set of pseudo measurements. ...
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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 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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2
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92
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Are there offsets in these accelerometers signals?
How you can see in the picture below, there are 3 signals from 3 piezo accelerometers placed on a oscillating 3D structure. The structure should vibrate only along the z axis (blue track), but there ...
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Quickly stopping a phone from attaching to a network
I struggled for a while to find which group I might ask this question in. Figured engineering minds would be the best.
Some time ago I discovered a good friend was in an abusive relationship. This ...
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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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Small wireless proximity device to alert me when my cat gets into my WiFi range
I have the following situation. My cat goes outside every day, the problem is I have no way of telling when he is back around the house unless I go outside myself.
I need some small wireless device I ...
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Meaning of SNR in Instrument Specifications
I am evaluating the specifications of an FTIR instrument (Bruker Vertex) and came across the following statements/items:
Signal-to-Noise 5 sec sample, 5 sec reference: >10,000:1 (<4.34 x 10-5
...
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How does free space path loss change with receiver's antenna's height
I have a question which seems like an easy one, but I couldn't find anything on Internet to be 100% sure.
The free space path loss equation is:
$$FSPL=20\text{log}(d)+20\text{log}(f)+20\text{log}(\...
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How to read the block diagram for the 2nd order integrator feedback system?
This is a prework for a lab, I haven't seen things in the picture before and have no idea on how to transfer this to an equation.
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How can I measure the impact of noise on a FFT?
Please, I have to solve a problem and I really need some help.
I have to give an efficient method to consider a maximum amplitude as a starting point to consider as noise the whole spectrum below ...
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How do mobile phones switch 4G/3G/2G?
I would like to know the algorithm of switching between 4g/3g/2g. When will the phone switch from 4G to 3G or from 3G to 2G, when we select for corresponding option in the mobile phone. Is it based on ...
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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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Filtering Long-duration Signal
I have a long-duration EMG signal (~4 hours long) with a sampling frequency of 1 kHz. If I want to filter the data with a low-pass filter in 10 Hz in MATLAB, should I filter the signal with ...
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Center line of cut-off periodic signal
What I am after is the center line of this wave, which is 0. How can I calculate that value though?
For example, run the code below for a simple example in Matlab. This will plot a simple sine wave ...
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Signals and systems convolution problem? [closed]
hey guys I'm having trouble with a convolution problem here
A continuous-time linear system has the input/output relationship
$$\int_{-\infty}^t (t-\lambda-2) x(\lambda) d{\lambda}$$
For $1 ≤ t ≤ ...
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Hilbert transform LTI
I'm studying the Hilbert transform and its properties. I found out that Hilbert transform can be considered as a linear time-invariant system. How can I show this? I guess this should be trivial as ...
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Finding the sampling period to avoid loss of signal
We have:
$$ s(t) = 4u(t)−u(t−1)−2u(t−2)−2u(t−3.5)+2u(t−4) $$
where $u$ is the Heaviside function.
I had to draw the graph and find the minimum sampling period so we wont have loss of signal. I have ...
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Response of a system to a step function (Heaviside function)
I'd like to compute the response to a step function of a electrical/thermal system. Generally I can "easily" compute the transfer function $H$:
$$H(\omega) = \frac{V_{out}(\omega)}{V_{in}(\omega)}$$
...
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Can wifi signal reception be improved by opening a door?
A wifi user is in a different room than the router. The computer is having a hard time connecting and receiving the wifi signal.
Can the wifi signal from the router to the computer be improved by ...
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signal-to-interference-plus-noise ratio (SINR) and others calculation
I am considering some empirical signal propagation models (like Hata, Ericsson models) to calculate 4 parameters:
Path loss
Received Signal Strength (RSS)
signal-to-interference-plus-noise ratio
...
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BER peroformance of MPSK and MQAM in Rayleigh fading channel
I have a question regarding bit error rate (BER) performance over the Rayleigh channel. I observed BER performance over the AWGN channel using Simulink in MATLAB. I used to change the "SNR" parameter ...
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What kind of signal is the signum function? A power signal or an energy signal?
I'm studying "signals and systems". We can indentify two kinds of signals: power signal and energy signal.
The definitions are:
Energy of a time-continous signal
$$ E_x = \int_{-\infty}^{+\infty}{|x(...
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What are the meanings of the second argument to the convolution?
I was trying to understand the convolution better and its mathematical properties and interpretations in engineering (specially in the context of computer vision). Recall the convolution:
$$ s(t) = (...
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What is a "window of length N" in a signal processing algorithm?
I am reading a scientific paper in which an algorithm for evaluating an electromyography signal is described and I just don't get the meaning of the word "window" in the following part of a sentence: (...
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Is it possible to "boost" a WiFi signal using an aluminum soda can?
I recently discovered that one of my roommates had attempted to boost the WiFi signal by cutting up a soda can and placing it near the router, like this:
My roommate was probably following an ...
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Best way to send a signal in a very low frequency (250Hz)?
I am a programmer facing an electronic question, so I thought here is the place to ask!
I have a magnetic field sensor which provides me with magnetic field values (XYZ axis) 250 times a second.
An ...
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Implications of concatenating EEG signals
I am wondering about the mathematical implications of concatenating very small windows from different trials. All of the trials are the same size, and are for the same period of time after a stimuli. ...
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