Signals Definition and 410 Threads

On page 7 of the attached document, it says that because "the above geometry does not depend on t", the trajectory of the first signal must be the same as the trajecotry of the second, just shifted by \Delta t. I don't understand: a) how it doesn't depend on t? there's a dt in the formula...

Hi friends, I'm new in this forum and very happy to be here. I need your guidance on what to do with my Signals and Systems course which I expect to turn into a failure. I'm studying Electronics Engineering and I think I'm going to fail Signals and Systems because I got 9 out of 100 on my first...

I have 2 questions:(at least answer on question) 1) What is an amplifier? Is amplifier or a booster are same thing? What does an amplification do with signals? If an booster/amplifier is connected in a DSL line so will it amplify DSL connection to get better speed? 2) How to make a portable...

As per the theory of general relativity nothing can travell faster than the speed of light. Therefore we would always be in the past light cone of a distant celestial body, say planet X in another solar system, that is 100 light years away. A minimum of 100 years would have to lapse before an...

From the lecture notes: h[n] = \frac{1}{2}(\delta[n] + delta[n-1]) via property: H(e^{j\Omega})=\sum_{-\infty}^{\infty}h[k]e^{-j\Omega k} becomes: H(e^{j\Omega})= \frac{1}{2}(1 + e^{-j\Omega}) than my lecture divided by e^{\frac{-j\Omega}{2}} resulting in: H(e^{j\Omega})=...

Homework Statement Input and system response is as follow: x[n] = r[n] - 2r[n - 1] + r[n - 2] h[n] = \delta[n - 2] The output is: y[n] = u[n - 3] Is that true? Homework Equations The Attempt at a Solution I draw the h[n] and x[n] and they looked as follows: As for...

Homework Statement The system with impulse response h(t) = a_{1}\delta(t-t_{1}) + a_{2}\delta(t-t_{2}). Is this system stable or not?Homework Equations The Attempt at a Solution I drew the h(t) response and I got something like that: but I don't really know how to prove it. There is no input...

I'm looking for a device that can record EM signals of unknown frequencies (unknown to me) emitted by devices. For example if I point my remote control at it and start pressing buttons it should record intermittent IR frequency surges. Or for example if I build an emitter to modulate an...

"Radio frequency (RF) is a rate of oscillation in the range of about 30 kHz to 300 GHz, which corresponds to the frequency of electrical signals normally used to produce and detect radio waves." - Quoted from Wikipedia. How can electrical signals be used to produce and detect radio waves...

hello friends, I have a voltage and current input signal in simulink which has a small phase shift between the two signals. Is their a way so that i can eliminate this phase difference to zero? thanks

Homework Statement The signal y(t) is generated by convolving a band limited signal x1(t) with another band limited signal x2(t) that is y(t)=x1(t)*x2(t) where: --> X1(jω)=0 for|ω| > 1000Π --> X2(jω)=0 for|ω| >2000Π Impulse train sampling is performed on y(t) to obtain: --> yp(t)=...

x(t) = t, 0 \leq t \leq 1; x(t) = 2-t, 1 \leq t \leq 2; x(t) = 0 ,otherwise. I want to draw this signal, and I have something similar to this Is that correct? Also this is not periodic right? I just want to be sure 100% Thanks!

Hi there, This is a different question I tried. The signal is given as x[n] = 2u[n+2] - 3u[n-2] +u[n-4], and it has values x[-2]=2, x[2]=-1 and x[4]=0. True or false? I think it's false cause If I plug in all the x in each case ie, -2, 2 and 4, into the signal, than I get 3 different...

Hi guys, I have this question in the book whether a signal is Power Signal or Energy Signal. From what I have read signal is an energy one if its time-averaged power is = 0, or its non periodic. For non-periodic signal V(t) \neq V(t+T) I tried to prove that V(t) = 230\sqrt{2} Sin...

Hello, I'm a newbie of signal processing, I would like to calculate a frf between two acceleration signals. I have several realizations of each signal. These signals are stationaries and they aren't triggered, so signal arrays doesn't have the same length. I have got these acceleration signal by...

Will we get a high frequency signal from convolving 2 high frequency signals? Also will we get a low frequency signal from convolving 2 low frequency signals? How about convolving one low and one high frequency signal? My intuition tells me its low frequency signal. Thanks for any...

Homework Statement Find the period of the signal x(t) = 2 + 4cos(40Pi*t) + 3cos(60Pi*t) + 4cos(120Pi*t). Homework Equations The Attempt at a Solution The fundamental frequency (fo) = 10 Hz, since that's the greatest common factor of all the frequencies of the cosine signals. So...

Not a specific question per se but... Is it possible to convolve a discrete-time signal with a continuous-time one? if you have x(n) and y(t) can you calculate the convolution of x and y (say, by taking y(t) for t in the set of integers or by treating each x(n) as its value multiplied by...

Hello.. Am an Electrical Engineer, my FYP concerns the artificial limbs... I made a small research about the nervous messages, and how it flows from the brain until it reaches the muscles. In the arm i found that there are 3 nerves (Ulnar, Median, and Radial nerve) which are responsible for arm...

I am a little confused about convolutions. I know that convolution is the multiplication and then integral of the two signals. The confusion starts at the commutative property. If i try to change the time-shift from signal to another for any 2 general functions or equations the commutative...

Obtain the digital words corresponding to the indicated analog signal levels, a through j, as shown in Figure P8.38, that would be assigned by an A/D system with 2 bits. http://img256.imageshack.us/f/eehmrw1.png/ a. None of the above b. a=11, b=01,c=10,d=01, and e=01 c...

Homework Statement \int_{-\infty}^{\infty}{u(t)e^{-t}(\delta(t+1)+\delta(t-1))dt Homework Equations \int_{-\infty}^{t}{u(t)dt = \left\{\begin{array}{cc}0,&\mbox{ if } t< 0\\t, & \mbox{ if } t>0\end{array}\right. \int_{-\infty}^{\infty}{f(t)\delta(t-a)dt} = f(a) The...

Hi, Suppose you have an OFDM signal, e.g. DVB-T. In this case the spacing between the carriers is 4464 Hz and there are 1705 carriers. So the total bandwidth is 7.61 Mhz in baseband. First: Am I right that the spectrum is wide but very sparse? So There is a peak at 0Hz, 4464 Hz, 8928 Hz...

how many types of brain signals are there? or if a person thinks of writing a word the signals that perform this action what are those called..? (brain signals is not my subject but i want this knowledge to further use it in a signals and systems project relating to human brain) thnx

Hey, I'm hoping this thread can clear up some confusion I have with complex signals and moving back and forth from physical signals to the mathematical models. I'll probably ask some questions specifically, but if you would like to help me please treat this whole post as a question because I'll...

I have an application that requires me to multiplex between >7 sinusoidal signals (15v ~1-100kHz) with as little distortion as possible. I'm not really sure what would be the best way to go about doing this though. My first thought would be to simply use a low capacitance multiplexer, like...

I mean, several light years from here, is it possible to distinguish between the signals coming from Earth and the massive amount of electromagnetic radiation emitted by our Sun? From a great distance, every solar system must appear dot-like. Is it possible that civilizations are actually...

Homework Statement I have difficulty in understanding the meaning of fundamental cutsets.I don't really know how to find the fundamental cutsets.Can someone please guide me.It would be the best if there are any examples and links cited for me.Thanks in advance.. Homework Equations...

HI ALL Well i want to know the power electronics required to transmit signals for sensors,limit switches ,push buttons up to PLC, and if analog device signals like potentiometer could be transmit tted with these ,how can i do this . i am using Plastic Optical Fibre and please help me with the...

What is the point of repeating the TR 90 degree pulse in MRI? I understand you must modify the TR time to get different T1 times, but since the echo signal is read, would'nt all the echo signals be read to the same intensity after a 90 degree pulse?

Question one Homework Statement x[n] = 5sin(0.22*pi) The root mean square (RMS) value eof a sin wave is known to be A/root(2) where A is the amplitude. If the noise in a system is known to have an RMS value of 0.5, what si the signal to noise ration (in dB) of the x[n] in this syetem...

what is the bandwidth of single tone signals? taking the F.T. for a cosine signal gives a delta at the signal's frequency, so does it mean that its bandwidth is zero since it is occupying only a single freq. in the FD.

I'm a math major having taken 1st yr physics, programming, lab electronics, and a EE minor of 4-5 courses on signal processing and linear systems (including couple grad courses). I'm also doing medical imaging research w/ the EE dept this summer. I didn't major in EE b/c I've no interest in...

hi yea umm is there any research/thinking regarding carrier wave signals being transmited vocally? jb

I'm logging the RPM of a scaled wind turbine using a laser and modified microphone (with a photocell instead of a coil). The signal is recorded using Audacity and is a series of troughs separated by the time it takes for one blade to pass through the beam (please see attached image below)...

Homework Statement No problem statement - just the following questions. Homework Equations 1.Display on a CRT is most similar to what reconstruction filter? 2.How many samples are required to represent a given signal without loss of information? 3.What signals can be reconstructed...

Homework Statement Suppose rocket traveler Amelia has a clock made on Earth. She flies to and back from a planet 12 light-years away (as measured from rest with respect to Earth) from Earth at a speed of 0.6c. Every year she sends a signal to Earth. How many signals does Earth receive by...

Hello all. I have two functions in time f_1(t) and f_2(t) composed of the same set of frequencies such that, say, f_1(t) = \sum a_n \cos(\omega t + d_1(t)) and f_2(t) = \sum b_n cos(\omega t) and I would like to find out the value of the phase difference (I've set the phase in f_2 equal...

Hi all, I am enrolled in an introductory signals and systems course at my university. I don't like talking down on my professors but in this case I can't help it. He is one of the worst teachers I have had in my life. I have visited his office hours but he's not really helpful in there...

Hi all! I wanted to have a little clarification about this line in relation to Fourier Series: (It's about a periodic and symmetrical signal) "x(t) is a periodic signal. As cos nwt is an even function and sin nwt is an odd function. So, if x(t) is an even function of t, then x(t) cos nwt...

can we obtain electrical energy from sound signals?? hello everyone.. i want to know that is there ny method or any apparatus to convert the sound signals into electrical energy efficiently such that it will glow a led or can acticate a buzzer! well i know about sound detector circuits...

How "bright" are radio and other EM signals? Greetings, I am wondering how "bright" man made EM signals such as radio are. That is, if they were in the visible range, how would they compare to visible light sources? Would they be barely visible? Would they be daytime sky bright in every...

Could anyone help me to understand the working of a antenna? In antenna, we are using voltage or current as signal input and how this could be converted into em waves and vice verse in receiver side?

The Question I want to understand how a sound wave changes in the form of its signal into the brain. I don't know the terminologies. I don't know what this subject is called. If you know the right terms or know where I should look, please fill me in. My question is: What is the form of...

Hey Guys, I'm a mechanical engineer (please forgive my ignorance) with an electrical engineering problem. I'm trying to control a small DC motor with speed and duration controls using a remote cell phone. I might also like the ability to receive temperature data from the motor back at the...

I will make this my discussion thread. I have many questions to ask which I will post here. Please keep checking. All help will be appreciated. My first question is: For discrete signal, we use variable 'n' and for continuous signal, we use variable 't'. But is the convolution integral valid...

I'm looking to create a radar in the public band (2.4GHz) to detect oncoming cars from a relatively short distance (around 9 meters). I have access to a signal generator which can generate the 2.4 GHz signal, as well as another generator to create a pulse train of around 3MHz. I also have all...

Is it possible to combine two AC signals that are slightly out of phase, but have the same frequency, voltage and current through an inductor, resistor series network.

The idea has been bounced around, and i thought to see if anyone here had any guidance before i tear into the literature. What kind of circuit is necessary to determine the frequency of an rf signal? The situation: An rf transmitter is pumping out waves (no modulation or data to be decoded)...

I've been working on this problem for around three hours, and I'm getting nowhere... I think it may be that I don't have even the most basic grasp of the material to even get a decent start on the problem, but hopefully someone here will be able to help me... Homework Statement Calculate...