Introduction to Signal Processing: Exponential Signals (Lecture 3)

[@HassanKhan-cs8ho]

Best gift at the start of 2023

[@adetoyesealbert2093]

It sure is

[@HamidRezaJarrah]

Thanks, Nathan for your very nice channel, as a Ph.D. student, I found you a perfect teacher.

[@jacobmalof]

These lectures + accompanying lab videos would be so freakin cool

[@LydellAaron]

YES. Needing this right now. Thank you. 4:09 I have used the real exponentials to envelope the sinusoids and bound them in time.

[@SumGuyzClone]

I think your discussion at ~26:30 on discrete vs continuous is exemplified by a video camara capturing the propeller of a helicopter. As it starts to spin, you can see it speed up, then seem to begin to rotate backwards as the RPM's begin to exceed the frame rate of the camara. Most intuitive way I can visualize this. Thank you for producing these videos!

[@individuoenigmatico1990]

At 26:00, in the figures you are representing the real parts of e^[iw•n], ie. cos(w•n). The fact that you noticed is a symmetry of the signals around frequency π. In fact due to cosine properties we have, for all n, cos([w+π]•n)=cos([w-π]•n) even if the complex signals e^(i[w+π]•n)≠e^(i[w-π]•n) due to the fact that sin([w+π]•n)=-sin([w-π]•n).

[@bernardalferlaten5222]

Thanks for the awesome teaching, had to scratch my head for a while to understand why the absolute value of a complex exp was equal to 1, but I got there 🙂

[@KymaSymposium]

At 17:37, shouldn't the functions be cos(t), cos(2t), cos(3t), and cos(4t) to match the waveforms on the right?

[@Rene_Christensen]

Or a half, one, two halves, three, to fit the underlying bin/time line mentioned.

[@chiachikuo2766]

15:20 should the energy and power be squared?

[@TheRsmits]

Shouldn’t the phase have a minus sign inside the cosine if it’s shifted to the right?

[@Rene_Christensen]

You are correct.

[@princyok8058]

Are the PowerPoint slides for this course available anywhere?

[@chadyonfire7878]

never understood this stuff like this way , thx

[@Jalda-c7g]

tank you! perfect! :)