The sequences x[n] = {1, 3, 4} and h[n] = {4, 1} both start at n = 0. Find the largest sample ymax of y[n] = x[n] ∗ h[n].
Convolution & LTI systems worksheet with answers
1.Easy
x[n] = {1, 3, 4}, n = 0…2h[n] = {4, 1}, n = 0…1
ymax =
2.Easy
The sequence x[n] is nonzero for n = -1…1 and h[n] for n = 3…5, as shown. Find the first index nfirst at which y[n] = x[n] ∗ h[n] can be nonzero.
x[n]: n = -1…1h[n]: n = 3…5
nfirst =
3.Medium
The input x(t) = 10·e−6tu(t) is applied to a system with h(t) = e−4tu(t). Find the output y(0.25) at t = 0.25 s.
x(t) = 10·e−6tu(t)h(t) = e−4tu(t)t = 0.25 s
y(0.25) =
4.Medium
The input x(t) = 2·e−5tu(t) is applied to a system with h(t) = e−4tu(t). Find the output y(1.5) at t = 1.5 s.
x(t) = 2·e−5tu(t)h(t) = e−4tu(t)t = 1.5 s
y(1.5) =
5.Hard
A system obeys y′(t) + 10·y(t) = 3·x(t). Find its impulse response at t = 0.5 s, h(0.5).
y′ + 10y = 3xt = 0.5 s
h(0.5) =
6.Hard
A pulse train has height 3, pulse width 1.25 ms and period 5 ms. Find the amplitude c1 of harmonic number 1, at 200 Hz.
A = 3τ = 1.25 msT = 5 ms
c1 =
Answer key
- 1. ymax = 19
- 2. nfirst = 2
- 3. y(0.25) = 0.7237
- 4. y(1.5) = 0.003851
- 5. h(0.5) = 0.02021
- 6. c1 = 1.35
Full step-by-step solutions: practise this topic on examproblems.com.