Signal Definition and 989 Threads

I am measuring the reflected power of a resonator for potential wireless applications. I'm pulsing the resonator with a 10.64GHz (resonate freq) pulsed waveform (10ns pulse width, 200ns period). Use an oscilloscope, it's easy to see the reflected pulse - with a maximum voltage just after the...

Hi all, I'm considering doing a masters in either signal processing or machine learning. I have a bachelor's in electrical and electronic engineering, and have a bit of experience (internships mostly) in both industry and research. I was wondering if there are a lot of career opportunities...

Hello. I am trying to build a version of a Chladni plate, which is a device that uses a modified speaker assembly to mechanically resonate a dish containing salt or some other powder. When the input signal reaches the resonant frequency of the plate, crazy patterns start to appear in the salt...

What is the difference between Random Signal and Random Process? A random process does not necessarily imply and ensemble of random signals. Is this correct? M

Homework Statement I badly needed an urgent help in Matlab. I have to create a Matlab function (M-File) that will output the low (flow) and high (fhigh) frequency components of a DTMF signal given the numeric symbol (x) (* and # not included). I don't even know where to start since...

What is the speed of propagation of an electric pulse compared to the speed of light: - In a normal copper wire. - In a superconductive wire.

Sketch the following signal u(t-3)-2u(t-8)+u(t-5) if it was u(t-3)+u(t-5) I'd be able to sketch it, but the 2u(t-8) is confusing me help me :( I can draw the first part u(t-3) how do I add the second to the graph and then the third

Hi friends, I was looking for signals which will have themselves as the Fourier transform. Few of them are given below. \frac{1}{\sqrt{2\pi}}e^{-\frac{t^2}{2}}\longrightarrow e^{-\frac{\omega^2}{2}} \sum_{k=-\infty}^{\infty}\delta(t-kT)\longrightarrow...

Homework Statement hello! i'm given a signal h(t) = v(t)*g(t) where g(t) is a distortion/noise that got added and has a very low frequency compared to v(t) i need to devise a method to clean up g(t) The Attempt at a Solution i'm thinking of to do the fft on the signal h(t)...

hello! i'm given a signal h(t) = v(t)*g(t) where g(t) is a distortion/noise that got added and has a very low frequency compared to v(t) i need to devise a method to clean up g(t) i'm thinking of to do the fft on the signal h(t), and remove the lower frequencies and do the inverse...

hi everyone, I need help in a project.I have a signal x(n)=(0.5^n)*u(n). i want to find the DFT of the signal for N1=50,N2=20,N3=11 and then the reconstruction of the signal. I don't know anything about MATLAB and i don't have any idea how i'll do this. My problem is the code so if someone can...

Hi, I have 2 questions here and hope some experts can answer them. Question 1: How to improve the signal distance of the IR led?What parameters in the datasheet that we should look into? I have purchased few IR leds but all of them can't shoot more than 3 metres. I noticed increasing...

Dear friends, I would like to know how can I remove an AC signal from a signal which is combination of AC+DC. AC signal 60V/50Hz DC=50V. Please suggest me a C code or any algoritham or a filter which can remove AC signal completely and I should be able to see only DC...

Homework Statement A 4m telescope has a 16bit controllr with a gain of 1 and must detect faint stars(M>15) without saturating the bright stars(M=8-10). (i) What is the max no of photo-electrons that can be registered before saturating the CCD? (ii) The zero point of the system is...

Hello. I went to get a new router because I finally decided to get wireless. I got a Linksys WRT120N which supposedly has a decent range, according to the sellsman. On my apartment the router is about ten meters and has a couple walls between it and the computer. The computer receives really...

If you connected a DC or AC source to the end of an single, infinitely long, straight wire suspended in free space (separated from anything), would propagation occur along the line?

Suppose you acquire the 31P NMR signal from a region of muscle of a healthy subject using a 3 Tesla magnet. Assume that the signal has contributions from ATP,PCR, Pi, and from an unknown phosphorous containing biochemical. Assume that all decay shapes are exponential. Note: H1- 42.575 MHz/T...

Homework Statement Given two constants, A and B, what is the energy of the following signal? f(t) = A*rect(t) + B*rect(t-0.5) Homework Equations E_f = \int_{-\infty}^{\infty} |f(t)|^2 The Attempt at a Solution E_f = \int_{-\infty}^{\infty} [A*rect(t) + B*rect(t-0.5)]^2 dt =...

Hi all, I'm having some trouble understanding the consequences of directly changing the frequencies in the spectrum of an audio signal. Let me give you an example: Let's say I have some audio signal, which I convert to a spectrum (in LabView, using a direct cosine transform (to avoid...

Hi all, First post here for me. 1. Problem Statement Find the fundamental period of: 3cos(1.3PiN) - 4sin(0.5piN +0.5Pi) 2. Relevant equations: T = 2PI / w 3. My attempt: Not sure how to proceed. By themselves the fundamentals period would be: 3cos(1.3PiN) w = 1.3Pi...

Homework Statement s(t)=13*cos(2000*pi*t + 100*sin(8*pi*t)) Determine the fundamental period of this signal, i.e., the shortest period. Homework Equations x(t)=A*cos(2*pi*f(c)*t + a*sin(2*pi*f(m) + phi)) A=13; f(c)=1000; a=100; f(m)=4; phi=0 Inverse Euler's - A*cos(omega*t + phi) =...

Do opamps amplify lineary down to very low signals like a few microvolts, the OP-07 for eg. I have an LM324 in moving coil phono preamp and the + input in which the AC coupled signal is going to is also connected to the + supply(6v) thru a 100K resistor. Is this to bias the opamp input because...

So I have access to a signal generator and a spectrum analyzer and one of the SG functions is to generate a sweep. Let's say the frequency starts from 50 MHz and goes up to 100 MHz, the amplitude can also be a sweep from one value to another The thing is what applications can that feature...

Modulation is the process of impressing an information bearing signal to a carrier for effective transmission over a long distance. example Am and FM used in radio transmission Analogue baseband signals of 0-4000Hz are shifted to 60-64Khz range. Communication systems often do not carry...

Homework Statement Question: Consider the sinusoidal signal: A*cos(\omegat + \phi) Determine the average power Homework Equations This is my first real attempt in signals and I am really confused with the question... I guess my question would be am I suppose to take the P = lim as t->...

Hi, I'm wondering how do we calculate the average Power of a random (non-periodic) signal. I know how to do it if the signal is periodic, but with a non-correlated Gaussian signal I'm a bit lost. Can anyone shed some light? Thanks,

i am new , so i am not sure if this is the rite place. my Question i want to show my students how to block the signal coming from a wireless router. Pl help!? i have tried wrapping the antenna with aluminium foil and putting the whole modem in an aluminium container, none of...

Analog Signal Loop/Switch Control? Hello fine people of this board. I have been working on a custom project here for a year or two and I'm stumped at this point. I am working with 16 analog sensor/signal loops (16 ins and 16 outs). There would be 2 main signal inputs, and 2 signal outputs...

Signal phase To cancel out 60 hz from my signal source(dynamic mic) I need to use an instrumention amp with another 60 hz source. How would I make the generated 60 hz have the same phase as the noise 60 hz?? and also do both signals have to be the same amplitude for this to work well?

signal frequency! suppose we have a signal varying randomly in amplitude with time...when we plot the frequency responce of this signal , we get a bandwidth of frequencies...My question is ' are all these frequencies present at all times??', or 'at any time , say t=to , only one of these...

What are some ways to improve signal to noise ratio for a microphone amplifier, beyond getting low noise components. My amplifier is a single opamp.

Statement: Capacitance and inductance in a circuit allow different frequencies to travel with differing degrees of attenuation and phase shift. This causes the received signal to be different from the signal sent. Question: With low and high pass filters, we can control what kind of signal...

I have a signal that is a sine wave plus an offset. I would like to measure the dc component and possibly also subtract it from the signal later. The signal is very slow (10th of Herz) and the offset changes on the order of minutes. I thought it should be possible to get a time average with an...

Career in DSP! I am doing b.e electrical and electronics from bits-pilani , india. I have just completed my second year. I had a course on signal and systems(fourier, laplace, sampling etc.) in my fourth semester.It has aroused my interest in dsp field. Can anyone here guide me on how to...

I am just a beginner in Signals and systems... In signal addition when we add two signals for example u(t) and u(-t), we are supposed to just add the values of both the signals at each and every point to get the sum,right? so in the case of u(t)+u(-t), what will be the sum value at t=0? Is it...

Homework Statement Let's suppose a set of numerical values {an} sent with a rectangular function, period T and with amplitude an. The signal can be expressed as follows: x(t)= \sum a_n \Pi_T (t-nT) To optimize detection at reception, the signal x(t) is processed through a filter whose...

Hello, I'm having an issue with a given problem. Homework Statement Using Parseval's Equation find the energy of the signal z(t)=\frac{4}{4+t^{2}} Homework Equations The book solves that problem by using the tent signal CTFT and duality property (i.e ). However that properly...

I am trying to create a program that would register it in a variable, when loudness of the microphone input signal exceeds some level for some amount of time. IS there a VB6 command that can allow me to measure the loudness of the input sound signal? Not on the sound card input. I have a...

I'm collecting voltage data, and I need a resolution of at least .05mV, which I think I can provide over the range of voltages with my inexpensive A/D board. The problem is, the signal fluctuates maybe 1mV up and down, and so I get a noisy signal. I've tried running a low-pass filter through it...

Hi everyone! I was trying to solve an old exercise but in a different way. It asks to find the signal x(t) given the graphs of |X(f)| and arg[X(f)]. Please refer to the attachment. My stategy this time is as follows: 1) find D(f) by deriving |X(f)| 2) antitransform D(f) and get d(t) 3)...

With DFT/FFT/SFTF or similar Fourier transforms, there's always a trade off between frequency and time resolution. It's like the 'uncertainty principle' for signal analysis. I have a few questions regarding this: 1: With a theoretical infinitely fast processor, is it possible to obtain...

I have a standard 8P8C modular jack (RJ45) and the small clip has broken off. Instead of cutting it off and re-wiring a new one I was interested to find out if I could attach magnets (how I will attach them is not important at this time) to the connector and have the magnets provide the...

I'm trying to design a system that will source DC power while transmitting a high impedance sourced AC signal superimposed onto this power signal. I'm sure this has been done in many applications, but I'm new to it. Currently I'm trying to use a basic adder circuit with an opamp to superimpose...

Installed a D-Link DIR-655 Router for my wireless network. The network consist of 3 desktop computers, 3 laptops, and 1 Blu-ray (netflix setup). The only problem is that one laptop has a signal strength that varies from (the high) that I have seen, 38Mbps down to 1Mbps. The trend seems to...

First off, this is not school related as my semester just ended and I've just been playing around with my fpga. My problem is that I'm trying to write to the ram module then read from it. I understand a little of the tristate buffer and inout signal but we didn't really go over this in class...

hello, y(t)=[cos(3t)]*x(t) x1(t) -> y1(t)=[cos(3t)]*x1(t) x2(t) -> y2(t)=[cos(3t)]*x2(t) x3(t) = a*x1(t)+b*x2(t) x3(t) -> y3(t)=[cos(3t)]*x3(t)=[cos(3t)]*(a*x1(t)+b*x2(t))= =[cos(3t)]*(a*[cos(3t)]*x1(t)+b*[cos(3t)]*x2(t)) y3(t) not equal a*y1(t)+b*y2(t) but the answers in the book said...

Hey everyone! I recently picked up a motorcycle for class/work commutes because walking home at 11pm from the lab is not fun. But I have come across something of interest. Some intersections keep a green light on the main street and red on cross streets until a car pulls up. Before...

Hi all, This is my first post, so please forgive me if this has already been discussed. There is a question that has perplexed me for years, and I am hoping someone at this forum can shed light or point me in the right direction. If two like charges separated by a distance, d, quickly and...

In the recent past, I've leaned towards no. The reason being that space is a 4-dimensional haystack. Even if a region in that 4D space contains advanced extra terrestrials and we scan it, the extra terrestrials would not necessarily be using EM waves for communications. If extra terrestrials...

I once heard a professor say no electrical signal according to present knowledge is truly analog in amplitude. I find it amazing considering how most schools go with the "world is analog" statement.. any views on this? BTW, the inherent discrete nature of the electric charge is the principle...