Basic Fourier-transform pairs
Table of Fourier Transform Pairs
Time-Domain: x(t) Frequency-Domain: X(f)
) 0 ( )
( >
− u t a
e at
f j a 2π
1 + )
0 ( )
(−t b>
u ebt
f j a 2π
1
− 2 )
( 1 2 )
(t 1T u t T
u + − −
f fT) sin(
π π
t t fb ) 2 sin(
π
π ( ) ( )
b
b u f f
f f
u + − −
)
δ(t 1
) (t−td
δ
e
−j2πftd) (t
u f j πf
δ
2 1 2
)
( +
t f0 2
cos π ( )
2 ) 1 2 (
1
0
0 f f
f
f − + δ +
δ t
f0 2
sin π ( )
2 ) 1 2 (
1
0
0 f f
f j
jδ f − − δ +
kt f j k
ke a 2π0
∑
∞−∞
=
) (f kf0 a
k
k −
∑
∞−∞
=
δ
∑
∞−∞
=
−
k
nT
t )
δ(
∑
∞−∞
=
−
k T
f k
T1 δ( )
Table of Laplace Transform Pairs
x(t) X(s)
1
1s s>0tn
n an integer ! 0
1 >
+ s
s n
n
eat s a
a
s >
−1 bt
sin 2 2 >0
+ s
b s
b
bt
cos 2 2 >0
+ s
b s
s
) (t f
eat F(s−a)
n att
e n an integer s na n s>a
− + )
(
!
1
bt
eatsin s−ab +b s>a
)
( 2 2
bt
eatcos s−sa−a+b s>a
) (
) (
2 2
bt
tsin
(
s22+bsb2)
2 s>0bt
tcos
(
2 2)
2 02
2 >
+
− s
b s
b s
∑
∞−∞
=
−
k
nT
t )
δ(
∑
∞−∞
=
−
k T
f k
T1 δ( )
Laplace transform operations
Operation )f(t F(s)
Addition f1(t)± f2(t) F1(s)±F2(s)
Scalar multiplication kf(t) kF(s)
Time Differentiation
dt t df( )
) 0 ( ) (s − f − sF
2 2 () dt
t f
d s2F(s)−sf(0−)− f′(0−)
3 3 () dt
t f
d s3F(s)−s2f(0−)−sf′(0−)− f′′(0−)
Integration
∫
f(t)dt 1 ( )s sF Convolution f1(t)* f2(t) F1(s)F2(s)
Time Shift f1(t−a)u(t−a),a≥0 e−asF(s)
Frequency Shift e−atf(t) F(s+a)
Scaling f(at),a≥0
) 1 (
a F s a
Initial Value f(0+) limsF(s)
s→∞
Final Value f(∞) lim ( )
0sF s
s→ , all poles of sF(s)in LHS