Signals Definition and 434 Threads

Hi all, I have measured the torque and the speed of a shaft when running at a variable speed. From the measurements, torque fluctuations are in the torque signals and I have the feeling that the fluctuations frequency is the shaft speed. I need to verify this with some signal statistics...

I am a beginer. I have read that any given signal whether it simple or complex one,can be represented as summation of orthogonal basis functions.Here, what the terms orthogonal and basis functions denote in case of signals? Can anyone explain concept with an example?Also,what are the physical...

Okay I have a question involving calculating the FFT of a signal from a sensor. I have simulated many different scenarios in MATLAB of various noise characteristics involving the signal. I want to take the FFT of a noisy signal. As long as my expected input signal has a higher amplitude than...

Hi all, I am looking for circuits that control the pulse widths of digital signals and their applications. Specifically, I am looking for circuits that map and a single input pulse width x to a single output pulse width y through function f(x)=y. Thoughts?

Homework Statement Homework EquationsThe Attempt at a Solution [/B] I'm trying to parse what the second and fourth questions are asking. https://en.wikipedia.org/wiki/Boolean-valued_function I clicked on "preciate" and "proposition" in the wikipedia link and got lost As a starter, what is...

Homework Statement What are the fundamental frequencies for a 50 kHz square waveform of 50% duty cycle and a 25 kHz sinusoidal waveform, respectively? (The duty cycle of a square waveform is the ratio between the pulse duration and the pulse period.) Homework Equations My teacher then gave...

I really hope you guys can help me. On the picture below we have 2 signals. Let's call signal X the one that is drawn with a dotted line. The other one we will call signal Y. Now given the 5 options below, where one and only one can be correct, which one would you choose? A) Signal X is...

Hello, If been for a while trying to find information about how Doppler effect affects modulated signals. When a transmitter is moving relative to a receiver, the receiver will have a shift in the carrier frequency that will vary as the transmitter gets closer or moves away from the...

Homework Statement Homework EquationsThe Attempt at a Solution I'd like to see if I have the right line of thinking in my solutions: a. The sampling frequency should be such that no aliasing or folding occurs, so it should be twice the frequency of the original signal. $$x(t) = -17...

Also can we have an analog signal in alternating current?

Hi everybody, I know that there are a lot of threads in this forum about Rindler coordinates but none of them have helped me :confused: I'll explain you my problem. First of all, my coordinates (x^0,x) (Cartesian coord., where x^0=ct) are related to the Rindler coordinates (\omega ^0,\omega)...

Can anyone tell me how to convert electrical lan signals into optical signals for wireless transmission via LEDs like they use it Li-Fi systems.

Does the following argument prove that any method of faster than light communication is impossible? 1. A transmitter sends a signal at 12:00 from point A to B faster than light by some hypothetical method. 2. A transmitter at point B is moving at a high speed (but less than speed of light)...

Hello all, I am currently studying as an EE and realized I messed up something with my career path. I am not sure if it possible to get an internship at a company for primarily DSP if you haven't taken a DSP class? If not, things could be mended if it were possible to take circuits 2...

How can a discrete time signal can be a vector? i cannot grasp the idea. i know MATLAB uses matrices which denote vectors, but how does a discrete time varying amplitudes be a vector?

I am beginner in image processing and want to do filtering in Frequency domain. I can understand that the frequency spectrum in case of 1D waves. It denotes what frequencies are present in a wave. If we draw the phase spectrum of cos(2πft) , we get an impulse signal at −f and +f, and it is...

Modern foil covered foam insulation and coated window glass unfortunately blocks mobile phone signals rather well. I'm aware of solutions that use broadband and wifi to tunnel through it but this seems like a problem waiting for a better solution. Are there any good/cheap alternatives to...

Hi all, In 2011 CDF experiment at Tevatron announced that they had reported W+2jets signal excess for 2 jets mass range around Mjj ~ 150 GeV but D0 experiment didn't see this signal anomaly using the same criteria. So have anyone an idea or recent reference how this discrepancy had...

Homework Statement "Let x[n] be a real-valued DT signal. Using the Pole-Zero plot of X(z), argue as to why: a. |X(e^jω)| is even in ω. b. ∠X(e^jω) is odd in ω. Hint: if x[n] is real, what can we say about the poles and zeros of X(z)?Homework Equations None. The Attempt at a...

Why is it necessary for the gain magnitudes of inverting and non- inverting ends to be equal in magnitudes to be able to reject the common mode signal? Also can someone explain the ratio obtained of voltage divider in difference amplifier. R4/R4+R3[1+R2/R1]= R2/R1 Where, R1 input resistance...

What gives the speed of signals? I've read somewhere that electrons move at 1mm/s in wire, so how is it possible that the signal goes so fast even if the current moves so slow?

It appears that sinusoidal signals are very useful in signal processing, communications, and information theory. I am curious to know very why. I understand that information can be transmitted via a sine wave, from the principle that sine waves of different frequencies are orthogonal. But use...

Hello Could I use a microprocessor (or anything else for that matter) to send a signal to a DAC that converts the signal to audio. For example, when I close a circuit the microchip sends a signal to the DAC to emit a certain sound. Thanks in advance for any responses and please inform me...

So a phase transition occurs when a system may minimize its free energy by spontanously breaking some symmetry. At least that is what I have learned from my current course so far. However I also did another course concerning phase transitions. In this case phase transitions were always...

Hello I know what is AC signal and DC signals purpose.. but may I know how to convent AC signals to DC signals to feed into the PIC?? Help pls

Systems and Signals questions---plots Homework Statement Problem: Express the bottom 5 plots in term of x(t) (the top plot) with its time shift, time scale, time reverse and superposition properties. (see attached picture) Homework Equations The Attempt at a Solution I have...

If you study a DC signal under an appropriate scope, you can see the switching transitions ; a pwm signal. But if you examine a battery, no matter how high temporal resolution you reach, you see a dc signal. What might be the explanation for this? electrons are being generated by a chemical...

From what I understand, laptops have a wireless adapter that sends radio signals at a specific frequency to connect to a wifi router. My guess is that the wireless adapter is some sort of radio wave emitter/reciever, and could in theory be used for any other purpose besides connecting to a...

Homework Statement Which of the signals is not the result of Fourier series expansion? options : (a) 2cos(t) + 3 cos(3t) (b) 2cos(\pit) + 7cos(t) (c) cos(t) + 0.5 Homework Equations Dirichlet conditionsThe Attempt at a Solution From observation, I thought all are periodic and so must be...

Signals and Systems Vs Circuits I I really just would like to know which course, in your opinion, was more difficult circuits I or signals? I've already taken circuits and signals is up next. Also, what should I be reviewing in order to prepare myself, during the break, for Signals and...

Quick question: I keep seeing the following terms in my reading on nuclear magnetic resonance: - Spectral linewidth - Spectral bandwidth - Signal bandwidth Are these all qualitatively different terms? Or are they more or less referring to the same thing?

I am having trouble getting this. I have been introduced to common mode and differential mode signals. I assumed the inputs to a differential amplifier is an ac signal... my instructor gave instruction on how to input such a signal to a circuit using SPICE, he used DC. is the common mode dc...

Somehow I have really hard time wrapping my head around the concept.I mean,I get it,but I can't seem to solve any questions regarding it. Here are some examples ,and I just get stuck.Its a part of test,so I think it shouldn't be that hard to solve,and if it looks hard,I know there are some...

Hi: I need to record a two analog signals, by using an ADC(of 20 bits resolution or higher), the two signals are very weak signals of signal to noise ratio about -30 db, so the two signals are very effective by the noise. the problem is : how to record these two signals at the same...

Whats the way to go to apply filter to a pulse signal? I have a signal with some weak triangle pulses, positive or negative, mixed with some very slow sine wave. I've tried to illustrate this in the attachment. The sine is actually slower than it looks in the chart I don't really know how low...

This #94 from the 2008 GRE: An observer O at rest midway between two sources of light at x = 0 and x = 10 m observes the two sources to flash simultaneously. According to a second observer O′, moving at a constant speed parallel to the x-axis, one source of light flashes 13 ns before the...

In general, by what considerations guide the decision to size a capactior to smooth voltage signals? For example, if I were to use a 3.3V regulator in a circuit design, what size cap should be set in place to ensure a smooth regulated voltage? My attempt at answering my own question would bet...

Which spaces, as studied in branches of mathematics such as linear algebra and functional analysis, such as vector spaces, inner product spaces, normed linear spaces, metric spaces, Hilbert spaces, Banach spaces etc. are most useful/frequently encountered in signal processing? My knowledge of...

Hello, I want to know what factors determine that a signal (radio wave, microwave, infra red) cannot be use for broadcasting but only point to point communication. I know that it has to do with frequency and the energy associated with it but cannot seem to have a concrete reason because of...

talking to someone about direct tv systems, how they talk between HD boxes over the rg6 coax line one person said one part sends a signal and it travels down the center of the center coax conductor and another signal going the other way travels down the outer part of the conductor, the surface...

The coherence I'm asking about is also known as magnitude-squared coherence. Let's say we have input A(t) and we look at the output B(t), the system L is linear but it has damping effect on the signals. In a long time, this damping will literally kill the high frequencies to zero. My...

Hello everyone! Could anyone explain to me the following: The 8085AH has 3 state signals: S0, S1 and IO/M*. S0 and S1 provide different type of machine cycles depending on their status. For example if the machine cycle is OpCode Fetch, we will get: S1=S0=1 and IO/M*=0. I don't get it...

Hi all, I'm in a bit of a dilemma. I have an opportunity to take Signals and Systems over the summer. However, I have not taken Differential Equations yet. A course on Electric Circuits is a prerequisite for this class and I ended up taking that last semester without any DE knowledge LOL...

I have read that for power signals : power = finite and energy = infinite Energy signals : power = 0 and energy = finite Can anyone give practical example for this...? Also we can represent power signal through Fourier series only but not through Fourier trransform..unlike energy signals...

Hi, I was wondering what would the Fourier transform of a signal like below give: s(t) = sin(2πt*10) ; t in [0s,5s] = sin(2πt*20) ; t in [5s,10s] I certainly did not expect it to give me 2 sharp peaks at frequencies 10Hz and 20Hz - because I understand that the addition of...

Obviously, this is a homework assignment, so I don't want it done for me; however, I am confused. Perhaps I am just confused by the problem or the wording, but I am totally stuck on what to do. I believe the output signal should be a convolution where Z = X + Y, and Y is the gaussian(0, 2)...

The discrete-time spectrum of a sampled continuous-time signal x(t) is shown in the figure above, where (A = 9.8exp(-j0.06π), B = 0.51π, C = -0.27π, and D = 1.9exp(-j0.41π) ). If the sampling frequency is 4928, which of the following continous-time signals is a possible solution for x(t)...

That's how the internet works across oceans, correct? I understand how a fiber optic cable transmits information, but how does it transmit everybody's information at once in just one dollar coin sized cable? One after the other? I find that hard to believe given how fast the internet is, even at...

I mean, what all can you modify in an electromagnetic wave? Wavelength and amplitude right? So, for example, why does my garage opener open my garage door and not my neighbor's? Does every single wireless device have its own specified wavelength that is just fractions of meter off from others?

how do we transfer many electrical signals of different frequency over a wire? i know its called frequency division mutiplexing, but i want to know how it is implemeted on hardware.