Recent content by truva

The phases won't change. Secondly, I am not sure but since you change the amplitudes, you may consider spectral leakage.

No I am not related any of the control theory. I study filtering and the effects of its initial conditions.

Could you advise a DSP book which explains state-space representation with initial conditions. Initial conditions part is important for me. Thanks.

As I understand the book is wrong (Notes On Digital Signal Processing by C. Britton Rorabaugh). If I replace the N by (N-1) in the denumerator of the formulation which is 5+.5*cos(2*pi*n/(N-1)), the results coincide exactly with that of MATLAB. Thank you for the link.

Hi all As far as I know Hanning window is defined as the following: .5+.5*cos(2*pi*n/N) and n is between [-(N-1)/2,(N-1)/2] here N is odd number. MATLAB functions "hanning" with symetric or periodic options or "hann" do not match with the results of the above formula. There is always a...

Continious FT of a rectangle is real valued but DFT of it is not!? Continious Fourier Transform of a rectangle with amplitude of 1 between [-u,u] is a real valued function (u is a positive number). Actually it is a sinc function. However when I use discrete Fourier Transform (fft) I obtain...

I just realized that I had find the result, but in a different form as the following: -1/4/u/pi^2/f^2*((-1)^(-2*u*f)+(-1)^(2*u*f)-2) And I checked it numerically that the function is exactly equal to the function below: u*(sin(pi*u*f)/u/pi/f)^2 I am not a mathematician and it is not...

For the Bartlett window below: w(t)=1-|t|/u for -u<t<u w(t)=0 otherwise the books say that the Fourier transform of it is W(f)=1/u*(sin(∏*f*u)/(pi*f)) I use symbolic toolbox of MATLAB and can find the transform of a rectangular window. But I couldn't find it in case of...

Actually if the signal satisfy above property the system is "additive". Which is f(x1+x2)=f(x1)+f(x2). Additionally the following property, f(λx)=λf(x) is the "homogenity". If a system is both "additive" and "homogen" it is said that the system is "linear".

When I use high-pass filter same thing happened at near zero frequency not at Nyquist frequency. Hence in both cases distortion is in stop band where the gain is about 1e-15. Therefore I can say that it is not a problem. But I don't know the reason. May be it is beause of bilinear...

Hello all, I obtained transfer function of a 8th order low-pass butterworth filter by bilinear transformation with frequency prewarping. When I plot the phase response of the filter for a given interval of frequency there are spreaded points near Nyquist frequency. (I used unwrap.m before...

I understand now. We look at the value of the VARIABLE s, and see the behavior of the SYSTEM. Thank you very much for your time.

Agree, if σ is positive it is on the right hand side not in the left hand side. This is what I am trying to say. But most of the DSP books, regarding the IIR filters, say that if σ is in left side the system will be stable and if it is in the right side the system MAY BE unstable. However σ...

If σ is negative -σ is positive. Hence exp(-σt) goes to ∞ not to 0 as t tends to ∞. !?

Laplace transform includes exp(-st) and s=σ+jω. σ is negative in the left side and hence exp(-st) goes to infinity. It is not stable. Where am I wrong?