## Forums More comp.dsp

## mirroring a signal before FFT - why?

inI am trying to make sense of some awful MATLAB code. The first thing it does is mirror the signal. By that I mean it doubles the array length,...

I am trying to make sense of some awful MATLAB code. The first thing it does is mirror the signal. By that I mean it doubles the array length, then puts a time-reversed signal at the newly created back half. So this would have the same amplitude spectum, but what else is going on? Possibly it increases the frequency resolution, as the time length is doubled. I wonder if the algorithm had som...

## February 2020 Publications Announcements :International Journal of Wireless & Mobile Networks (IJWMN)

International Journal of Wireless & Mobile Networks (IJWMN) ISSN:0975-3834 [Online]; 0975-4679 [Print] http://airccse.org/journal/ijwmn.html ...

International Journal of Wireless & Mobile Networks (IJWMN) ISSN:0975-3834 [Online]; 0975-4679 [Print] http://airccse.org/journal/ijwmn.html ********************************************************************* Scope & Topics ============== The International Journal of Wireless & Mobile Networks (IJWMN) is a bi monthly open access peer-reviewed journal that publishes...

## Call for Workshop Proposals for the 11th International Conference on Computational Creativity (ICCC'20)

------------------------------------------------ =E2=80=A8 The 11th International Conference on Computational Creativity (ICCC'20) June 29...

------------------------------------------------ =E2=80=A8 The 11th International Conference on Computational Creativity (ICCC'20) June 29 =E2=80=93 July 3 2020, Coimbra, Portugal =E2=80=A8 Call for Workshop Proposals =E2=80=A8 Held: during 29th - 30th June at ICCC'20 =E2=80=A8 workshops-iccc20@computationalcreativity.net http://computationalcreativity.net/iccc20/=E2=80=A8 =E2=80=A8 Pl...

## Holiday Greetings

inHere's wishin' all of you guys a very Merry Christmas and a Happy New Year! Of course, these good wishes are also directed at those of you...

Here's wishin' all of you guys a very Merry Christmas and a Happy New Year! Of course, these good wishes are also directed at those of you who do not celebrate Christmas such as: Muslims, Hindus, atheists, Buddhists, software engineers, Sikhs, Jews, filthy IIR filter designers, Shinto, Bolsheviks, Democrats, U.S. senator Mitch McConnell, Neo-Pagans, transsexual lesbians, Government Emp...

## Band Stop Filter

inSomeone is using this algorithm for high, low and band pass filter coefficients and wants to adapt it for band stop filters. ( y% is an...

Someone is using this algorithm for high, low and band pass filter coefficients and wants to adapt it for band stop filters. ( y% is an integer value that goes from filter length / 2 to +filter length / 2 ) IF y% = 0 THEN c = 1 ELSE IF BandPass THEN th1 = (fh - fl) * pi * y% ' Fhigh and Flow of passband th2 = (fh + fl) * pi * y% c = SIN(th1) * COS(th2) / th1 ...

## is there a name for setting weak amplitudes to zero?

inClipping is when you set a strong amplitude to some fixed limit. But what about the other end - when it is small, and those tiny amplitudes are...

Clipping is when you set a strong amplitude to some fixed limit. But what about the other end - when it is small, and those tiny amplitudes are replaced by zero?

## Impulse invariance method

inI have a laplace transfer-function G(s)=k(1+sT)/s*2 which I need the discrete-time version G(z) using impulse invariance method. Using...

I have a laplace transfer-function G(s)=k(1+sT)/s*2 which I need the discrete-time version G(z) using impulse invariance method. Using partial fractions I get G(s) = c1/s + c2/s^2 c1=kT and c2=k However when I use Matlab c2d and select "impulse" it gives me a different version though the first term c1 is right. Matlabs second term c2 is negative. I assume for multiple pole...

## Flash website- end of an era

inOver 10 years ago I started a website ( www.fourier-series.com)in which I b= uilt interactive flash programs to teach various engineering...

Over 10 years ago I started a website ( www.fourier-series.com)in which I b= uilt interactive flash programs to teach various engineering concepts. I In= itially designed these programs to personally understand DSP and then to pa= ss along what I learned to others****. These topics were fourier series, di= screte fourier series, fourier transforms filtering I/Q modulation and also= some RF s...

## Doppler effect detection

inHi all, is it possible to know, without any prior, if an incoming signal has a Doppler effect? That's it, to know if the source is...

Hi all, is it possible to know, without any prior, if an incoming signal has a Doppler effect? That's it, to know if the source is moving to (or away from) the detector without any knowledge of the frequency. I can imagine that if the source is not moving directly towards (or away) the detector, but with an angle, the Doppler effect changes hence it is detectable. How about a dir...

## LOW SNR FFT

inHello, I am processing an audio signal with CS4244 codec at 24 bits and 48kHz. Every 2048 samples the FFT is calculated and its...

Hello, I am processing an audio signal with CS4244 codec at 24 bits and 48kHz. Every 2048 samples the FFT is calculated and its amplitude. Without input signal I get FFT values ââclose to 30dB. With maximum input values ââ(overflow) I get values ââof 90dB, with a scale of 0 to 120dB. Why not get a dynamic range of 100-110dB as is logical

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