2 main parts, the first was on properties of CTFT and DTFT. Handout was given. What happens to the transform when we do things to the time domain, such as scaling. Remember important thing, doing \(x\left ( 2t\right ) \) in time domain result is new signal which is squeezed version of \(x\left ( t\right ) \), but we can still recover the original, but in discrete time effect of \(x\left [ 2n\right ] \) could be to produce a new sequence which we can’t recover from the original. See notes for examples. So watch out for this., Learn the properties and proof of them. Learn how multiplication of summation and making it a double summation. Watch for indices.
Went over the dirac delta function \(\delta \left ( t\right ) \) and how to use in. Sniffing property.
The rest of the lecture was on aliasing. A signal with 2 harmonics was given, we sample it under Nyquist, and using spectrum, the result is analyzed. Learn how to do this. I need to make a more detailed diagram as shown in the notes. learn the boundaries of the spectrum and the window used.
I made some notes on this, see below in the study notes section.
HW1 solutions returned.