Recent content by elibj123

MATLAB fft returns the signal spectrum both for positive and negative frequencies. Of course in your case the signal is real so its spectrum is symmetric under conjugation. When you multiplied by a window, you eliminated the negative frequencies of the signal, thus transforming it to a complex...

It really doesn't make much sense to estimate the parameters of a time-varying system, unless you have the model for the time dependence of the parameters as well (periodicity, explicit functional form?) or you have some specific real-time application that I can't think off right now. Anyway...

If the sines are of the same frequency, use their multiplication sin(ft+a)sin(ft+b)=0.5[sin(a-b)+sin(ft+(a+b)/2)] Averaging over a complete cycle (1/f) will kill off the second sine, and will leave you with 0.5sin(a-b), which you can easilly derive the phase difference from

This is wrong: If I shift my signal x1(t) by -2 I get y2(t)=x(2(t−2)) ---------------- The function is H{x(t)}=x(2t) What it means is take any occurrence of t in your input, and replace it with 2t. So we look at x2(t)=x1(t-2) And we want to get its output: we replace any t with 2t: so we...

Well - taking the convolution sum and truncating it to some finite range is effectively taking an FIR approximation of a given IIR filter, which is actually one of the techniques to design FIR filters. As a practical way to model a system, it's ok, it can even be pretty accurate - eventually...

Your equation is only a nice way to introduce an envelope with frequency f1-f2 and the oscillator (of high frequency f1+f2) that is bound by it. It does not mean the signal contains more than the two original frequencies f1 & f2, you still get two pure spectral lines only at f1 & f2. But...

Any non-linear device (see, diode) outputs all the harmonies of an input sinusoidal signal. This is due to the fact that the expression (sin(\omega t))^{n} contains (among other frequencies), the harmony sin(n \omega t) given that you know the input frequency\ies and the desired harmonies...

I'm studying the MUSIC algorithm in order to implement it in some project of mine, but I have some difficulties understanding the mathematical derivations done in the original Schmidt paper. For those of you who have access to this paper, I'll appreciate your time and help. The author begins...

I think there are many methods to solve this. From the top of my mind - allocate a specified memory space of flags, that each processor triggers while writing.

In some exercises I've stumbled upon a function which is denoted \gamma_{m}(n) with m,n natural. I've no idea what is the definition of the function and could not infer from the exercises. Searching google yielded nothing, as it kept suggesting me the OTHER Gamma function. Can anyone here help...

As you may have learned in introductory linear algebra, the objects of a vector space, need not necessarily be vectors. Actually, you may have learned of spaces of polynomials. So, you must be aware, that the space of functions may also serve as a vector space. You can also define operators...

Why don't you also ask how a ball knows to fall down when I throw it? Now that you've read my post you should realize the flow of yours.

The path that takes the least energy, is the path that an actual particle will travel along (a result of minimum action principle) which is the path that abides Newton's Second Law, so it will solve the ODE: \frac{d^{2}\vec{x}}{dt^{2}}=\vec{F}(\vec{x}) (F being the vector field)

Noticed how each of R6,7,8 has one end connected to E2+ and the other connected to E2-? So Actually they're parallelly wired to E2. You have the same for R3,4,5 and E1. That actually leaves you with a pretty simple circuit, which I'll let you draw on your own.

The primitive function of exp{-x^2} is not elementary, therefore cannot be expressed in simpler terms than the error function which is numerically approximated. As for the values of the integral as m tends to large numbers, this is an instance of the Riemann-lebesgue lemma, which generally...