The table below provides a number of unilateral and bilateral
z-transforms. The table also
specifies the region of
convergence.
The notation for z
z found in the table below may differ from that found
in other tables. For example, the basic z-transform of
un
u
n
can be written as either of the following two
expressions, which are equivalent:
zz−1=11−z-1
z
z
1
1
1
z
-1
(1)
Table 1
| Signal |
Z-Transform |
ROC |
|
δn−k
δ
n
k
|
z−k
z
k
|
Allz
All
z
|
|
un
u
n
|
zz−1
z
z
1
|
|z|>1
z
1
|
|
−u(−n)−1
u
n
1
|
zz−1
z
z
1
|
|z|<1
z
1
|
|
nun
n
u
n
|
zz−12
z
z
1
2
|
|z|>1
z
1
|
|
n2un
n
2
u
n
|
z(z+1)z−13
z
z
1
z
1
3
|
|z|>1
z
1
|
|
n3un
n
3
u
n
|
z(z2+4z+1)z−14
z
z
2
4
z
1
z
1
4
|
|z|>1
z
1
|
|
(−αn)u(−n)−1
α
n
u
n
1
|
zz−α
z
z
α
|
|z|<|α|
z
α
|
|
αnun
α
n
u
n
|
zz−α
z
z
α
|
|z|>|α|
z
α
|
|
nαnun
n
α
n
u
n
|
αzz−α2
α
z
z
α
2
|
|z|>|α|
z
α
|
|
n2αnun
n
2
α
n
u
n
|
αz(z+α)z−α3
α
z
z
α
z
α
3
|
|z|>|α|
z
α
|
|
∏
k
=1mn−k+1αmm!αnun
k
1
m
n
k
1
α
m
m
α
n
u
n
|
zz−αm+1
z
z
α
m
1
|
|
|
γncosαnun
γ
n
α
n
u
n
|
z(z−γcosα)z2−(2γcosα)z+γ2
z
z
γ
α
z
2
2
γ
α
z
γ
2
|
|z|>|γ|
z
γ
|
|
γnsinαnun
γ
n
α
n
u
n
|
zγsinαz2−(2γcosα)z+γ2
z
γ
α
z
2
2
γ
α
z
γ
2
|
|z|>|γ|
z
γ
|