Started by in comp.dsp3 years ago 11 replies

Usually when I ask about delta-sigma ADCs in FPGAs the comments are along t= he lines of "terrible idea", "can't mix analog and digital", etc. ...

Usually when I ask about delta-sigma ADCs in FPGAs the comments are along t= he lines of "terrible idea", "can't mix analog and digital", etc. I'm very= much not convinced. =20 I think people have a view of the ADC as being a device with very balanced = specs, resolution, SNR, etc. In this application we need significantly mor= e resolution than we do accuracy. The measurement is differ...

## two dimensional chirp z-transform

Started by in comp.dsp3 years ago

Hello All, would anyone please give me an illustration how to perform 2D czt in matlab? I use the row-column method used in normal fft to...

Hello All, would anyone please give me an illustration how to perform 2D czt in matlab? I use the row-column method used in normal fft to perform 2D czt transform on the Gaussian signal. amp=exp(-pi*(X.^2+Y.^2)/w0^2); tmp2=czt(amp,M,wx,ax); amp_f2=czt(tmp2.',N,wy,ay); The result doesn't make sense since Gaussian should remain as Gaussian after czt. Originally, I think the signal is ...

## daily puzzle

Started by in comp.dsp3 years ago 7 replies

A quickie. No diagram, but no need. Given a unit cube, vertices labeled ABCD on the top face, EFGH on the bottom; where A E, B F, ...

A quickie. No diagram, but no need. Given a unit cube, vertices labeled ABCD on the top face, EFGH on the bottom; where A E, B F, etc. Draw diagonals GD and BD, across the appropriate faces. What is the angle GDB? You have two minutes, no calculator, pen and paper only - -- Rich

## Wiener Filter

Started by in comp.dsp3 years ago

...

https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-011-introduction-to-communication-control-and-signal-processing-spring-2010/readings/MIT6_011S10_chap11.pdf I refer to these notes. Ive been using Wiener filters for some time now but it is teh causal version. I am puzzled by the uncausal one because it is unstable. Therefore how do people manage to use it? Is

## cetacean communication research

Started by in comp.dsp3 years ago 3 replies

The Vancouver Canucks have the orca as their main logo. Unfortunately they recently lost their series against the Vegas Golden Knights. I...

The Vancouver Canucks have the orca as their main logo. Unfortunately they recently lost their series against the Vegas Golden Knights. I think they would have better luck if they donated more (or some?) money in support of the Southern Resident orca pods, maybe including some to me for research into cetacean communication :-) though that would require me to do some work (not that my four ...

## FFT Question

Started by in comp.dsp3 years ago 7 replies

Why is it that in older textbooks the DFT or FFT is defined as having scaling of (1/N) for direct FFT whereas in newer ones it doesn't? If we take...

Why is it that in older textbooks the DFT or FFT is defined as having scaling of (1/N) for direct FFT whereas in newer ones it doesn't? If we take the DFT of say 1,1,1,1 the answer is 4 but surely an answer of 1 makes more sense as it is the average value. of 4 ones. I know people say - "Oh we can scale it later", but it doesn't make mathematical sense. The other point is that the

## FIR filter design

Started by in comp.dsp3 years ago 2 replies

I am trying a simple example using frequency sampling. Therefore I have N=16 weights. W=[w0 w1.....w15] and I make then as follows W=[1 1 1 1...

I am trying a simple example using frequency sampling. Therefore I have N=16 weights. W=[w0 w1.....w15] and I make then as follows W=[1 1 1 1 1 0 0 0 0 0 0 0 1 1 1 1 ] as magnitude and the phase is -k*pi*(n-1)/N where k is from 0 to N/2 giving a frequency sampling complex vector of H=[h0 h1 h2 ....h15] Now according to textbooks I have to have conjugate symmetry but exactly how does t...

## CFP: Special Issue JCR Q2 Entropy journal (IF:2.419). "Artificial Intelligence and Complexity in Art, Music, Games and Design"

Started by in comp.dsp3 years ago

Journal: Entropy (ISSN 1099-4300), section "Complexity". JCR Journal with Impact factor: 2.419 (Q2). Deadline for manuscript submissions: 30...

Journal: Entropy (ISSN 1099-4300), section "Complexity". JCR Journal with Impact factor: 2.419 (Q2). Deadline for manuscript submissions: 30 September 2020. URL:https://www.mdpi.com/journal/entropy/special_issues/ai_complexity Flyer: https://www.mdpi.com/journal/entropy/special_issue_flyer_pdf/ai_comp= lexity/web Dear colleagues, A major=E2=80=94potentially unachievable=E2=80=94challeng...

## Is fixed point arithmetic important anymore

Started by in comp.dsp3 years ago 5 replies

DO many people still do DSP in fixed point or are the processors mostly floating point and the DSP designer no longer needs to work in fixed point?

DO many people still do DSP in fixed point or are the processors mostly floating point and the DSP designer no longer needs to work in fixed point?

## Fourier Series

Started by in comp.dsp3 years ago 4 replies

We all know that if you have an even function you have only cosine terms an= d an odd function only sine. When the function is neither even nor...

We all know that if you have an even function you have only cosine terms an= d an odd function only sine. When the function is neither even nor odd you = get both, or do you? This suddenly struck me. Suppose you have=20 f(x)=3Dsin(x) - this is odd since f(-x) =3D -f(x) f(x)=3Dsin(x)+1 is neither even nor odd. Now f(-x) ne -f(x) But this is just a dc level shift. Could you not therefo...