Pacchetto 6

Question 1

Frequency domain

Answer 1

Each armonic can be seen as the sum of conterotaring vectors having the same amplitude and symmetry respect to real axis.

Question 2

Consider a signal g(t)

Answer 2

Is possible to demonstrate that g(t) can be decomposed in a sum of harmonic signals

Question 3

It s possible to see Acos(wt) by…

Answer 3

Two rotating vectors having amplitude of A/2 and rotating at angular speed +- w. Are alligned on real axis at null time.

Question 4

It is possible to see Bsin(wt) by

Answer 4

The sum of two vectors having amplitude of B/2 with +-w which are aligned on the immaginary axis at null time

Question 5

The function: h(t)=Acos(wt)+Bsin(wt) can be seen as…

Answer 5

The sum of two vectors with amplitude C/2 rotating with -+ w and forming an angle +- phi with real axis.

Question 6

Transform of periodic signal steps:

Answer 6

• Harmonic fk and -fk
• multiplying by e^(-i2pifkt) freeze w=2pifk
• multiplying by e^(-i2pi-fk t)
• the components at frequency fk -fk give two component that are complex coniugate pairs

Question 7

A generic function h(t) can be deconposed in

Answer 7

An even part and an odd part

Question 8

Deterministic signal

Answer 8

h(t)=h(t+-nTo) n=1,2,3 fo=1/To

Question 9

Fourier transform for non-periodic signal

Answer 9

• HP T infinite
• f0 tends to 0
• the spacing among its harmonic comp. tends to zero.