Difference between revisions of "ECE301 Bonus questions" - Rhea

Latest revision as of 10:27, 10 February 2013

Linear and non-linear examples

Linear system: y(t)=2x(t)+ 3 Non-linear system: y(t)=x(t)^2 + x(t) + 3

Causal and non-causal

Causal system: y(t)=2x(t-21) Non-causal: y(t)=4x(t+11)

Time invariant and time variant

Time invariant: y(t)=5cosx(t)+1 Time variant: y(t)=x(t)sin(t)

With and without memory

With memory: y[n]=4x[n-5]+2x[n-2] Without memory: y[n]=x[n]^2+x[n]+2

Invertible and non-invertible

Invertible: y[n]=x[n]+y[n-22] Non-invertible: y[n]=4x[n]^2-11x[n]

Stable and non-stable

Stable: y[n]=x[n]^2+x[n] Non-stable: y(t)=k*x(t)

Question:

$ f(t)= u(t) $ $ g(t)= 1 $ at $ 1 \le t \le 2 $ Solve for convolution.

Answer:

$ h(t)=0 $ at $ t \le 1 $ $ h(t)=t-1 $ at $ 1 \le t \le 2 $ $ h(t)=t-2 $ at $ 2 \le t $

Question

T/F? The sum of two peroid function is always a peroid function.

Answer:

False. Example: x1(t)=4cos(2t) x2(t)=5sin(2pi*t) y(t)=x1(t)+x2(t) y(t) is not a period funtction.

Back to first bonus point opportunity, ECE301 Spring 2013