حوزه زمان
x
[
n
]
{\displaystyle x[n]\,}
حوزه فرکانس
X
(
ω
)
{\displaystyle X(\omega )\,}
توضیحات
δ
[
n
]
{\displaystyle \delta [n]\!}
1
{\displaystyle 1\!}
δ
[
n
−
M
]
{\displaystyle \delta [n-M]\!}
e
−
i
ω
M
{\displaystyle e^{-i\omega M}\!}
M عدد صحیح
∑
m
=
−
∞
∞
δ
[
n
−
M
m
]
{\displaystyle \sum _{m=-\infty }^{\infty }\delta [n-Mm]\,}
∑
m
=
−
∞
∞
e
−
i
ω
M
m
=
1
M
∑
k
=
−
∞
∞
δ
(
ω
2
π
−
k
M
)
{\displaystyle \sum _{m=-\infty }^{\infty }e^{-i\omega Mm}={\frac {1}{M}}\sum _{k=-\infty }^{\infty }\delta \left({\frac {\omega }{2\pi }}-{\frac {k}{M}}\right)\,}
M عدد صحیح
u
[
n
]
{\displaystyle u[n]\!}
1
1
−
e
−
i
ω
{\displaystyle {\frac {1}{1-e^{-i\omega }}}\!}
e
−
i
a
n
{\displaystyle e^{-ian}\!}
2
π
δ
(
ω
+
a
)
{\displaystyle 2\pi \delta (\omega +a)\,}
a عدد حقیقی
cos
(
a
n
)
{\displaystyle \cos(an)\!}
π
[
δ
(
ω
−
a
)
+
δ
(
ω
+
a
)
]
{\displaystyle \pi \left[\delta (\omega -a)+\delta (\omega +a)\right]}
a عدد حقیقی
sin
(
a
n
)
{\displaystyle \sin(an)\!}
π
i
[
δ
(
ω
−
a
)
−
δ
(
ω
+
a
)
]
{\displaystyle {\frac {\pi }{i}}\left[\delta (\omega -a)-\delta (\omega +a)\right]}
a عدد حقیقی
r
e
c
t
[
(
n
−
M
/
2
)
M
]
{\displaystyle \mathrm {rect} \left[{(n-M/2) \over M}\right]}
sin
[
ω
(
M
+
1
)
/
2
]
sin
(
ω
/
2
)
e
−
i
ω
M
/
2
{\displaystyle {\sin[\omega (M+1)/2] \over \sin(\omega /2)}\,e^{-i\omega M/2}}
M عدد صحیح
sinc
[
(
a
+
n
)
]
{\displaystyle \operatorname {sinc} [(a+n)]}
e
i
a
ω
{\displaystyle e^{ia\omega }\!}
a عدد حقیقی
W
⋅
sinc
2
(
W
n
)
{\displaystyle W\cdot \operatorname {sinc} ^{2}(Wn)\,}
tri
(
ω
2
π
W
)
{\displaystyle \operatorname {tri} \left({\omega \over 2\pi W}\right)}
عدد حقیقی W
0
<
W
≤
0.5
{\displaystyle 0<W\leq 0.5}
W
⋅
sinc
[
W
(
n
+
a
)
]
{\displaystyle W\cdot \operatorname {sinc} [W(n+a)]}
rect
(
ω
2
π
W
)
⋅
e
j
a
ω
{\displaystyle \operatorname {rect} \left({\omega \over 2\pi W}\right)\cdot e^{ja\omega }}
اعداد حقیقی W , a
0
<
W
≤
1
{\displaystyle 0<W\leq 1}
{
0
n
=
0
(
−
1
)
n
n
elsewhere
{\displaystyle {\begin{cases}0&n=0\\{\frac {(-1)^{n}}{n}}&{\mbox{elsewhere}}\end{cases}}}
j
ω
{\displaystyle j\omega }
فیلتر مشتقگیر
W
(
n
+
a
)
{
cos
[
π
W
(
n
+
a
)
]
−
sinc
[
W
(
n
+
a
)
]
}
{\displaystyle {\frac {W}{(n+a)}}\left\{\cos[\pi W(n+a)]-\operatorname {sinc} [W(n+a)]\right\}}
j
ω
⋅
rect
(
ω
π
W
)
e
j
a
ω
{\displaystyle j\omega \cdot \operatorname {rect} \left({\omega \over \pi W}\right)e^{ja\omega }}
اعداد حقیقی W , a
0
<
W
≤
1
{\displaystyle 0<W\leq 1}
1
π
n
2
[
(
−
1
)
n
−
1
]
{\displaystyle {\frac {1}{\pi n^{2}}}[(-1)^{n}-1]}
|
ω
|
{\displaystyle |\omega |\!}
{
0
;
n
odd
2
π
n
;
n
even
{\displaystyle {\begin{cases}0;&n{\mbox{ odd}}\\{\frac {2}{\pi n}};&n{\mbox{ even}}\end{cases}}}
{
j
ω
<
0
0
ω
=
0
−
j
ω
>
0
{\displaystyle {\begin{cases}j&\omega <0\\0&\omega =0\\-j&\omega >0\end{cases}}}
تبدیل هیلبرت
C
(
A
+
B
)
2
π
⋅
sinc
[
A
−
B
2
π
n
]
⋅
sinc
[
A
+
B
2
π
n
]
{\displaystyle {\frac {C(A+B)}{2\pi }}\cdot \operatorname {sinc} \left[{\frac {A-B}{2\pi }}n\right]\cdot \operatorname {sinc} \left[{\frac {A+B}{2\pi }}n\right]}
اعداد حقیقی A , B عدد مختلط C
![{\displaystyle x[n],\;n\in \mathbb {Z} }](https://wikimedia.org/api/rest_v1/media/math/render/svg/83b783e3bb4f41250a3bce26399b1885f0e2c975)
![{\displaystyle X(\omega )=\sum _{n=-\infty }^{\infty }x[n]\,e^{-i\omega n}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/553acaf0fb714decb09013e12275ca65bed638d7)
![{\displaystyle x[n]\,}](https://wikimedia.org/api/rest_v1/media/math/render/svg/b575dce543a2cf10a5a3e108204b928c2c9aaa54)
![{\displaystyle \delta [n]\!}](https://wikimedia.org/api/rest_v1/media/math/render/svg/1553d02b03c2a79a43f7862ebfb8352705b0b87c)
![{\displaystyle \delta [n-M]\!}](https://wikimedia.org/api/rest_v1/media/math/render/svg/2dd610c46bdeb2682e719b6a0b445c1cf1893639)
![{\displaystyle \sum _{m=-\infty }^{\infty }\delta [n-Mm]\,}](https://wikimedia.org/api/rest_v1/media/math/render/svg/d3ce55d69101c8a851f1b8f09c0492852e8e9e49)
![{\displaystyle u[n]\!}](https://wikimedia.org/api/rest_v1/media/math/render/svg/8d2911183bef1ad935d3bc8b5c1be97bac439b7f)
![{\displaystyle \pi \left[\delta (\omega -a)+\delta (\omega +a)\right]}](https://wikimedia.org/api/rest_v1/media/math/render/svg/b949fed13f25129a9f8634cb4c0aa34354b0320a)
![{\displaystyle {\frac {\pi }{i}}\left[\delta (\omega -a)-\delta (\omega +a)\right]}](https://wikimedia.org/api/rest_v1/media/math/render/svg/7b48e8676730fb37bcadaea9b1bb342d107cf2f9)
![{\displaystyle \mathrm {rect} \left[{(n-M/2) \over M}\right]}](https://wikimedia.org/api/rest_v1/media/math/render/svg/4fa40f5391166dc137b30a45584c1de1a33b2f8c)
![{\displaystyle {\sin[\omega (M+1)/2] \over \sin(\omega /2)}\,e^{-i\omega M/2}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/883ef01f74f9697fd3a68706785bc6e702c8f961)
![{\displaystyle \operatorname {sinc} [(a+n)]}](https://wikimedia.org/api/rest_v1/media/math/render/svg/3526652071fa8be34f6bccac88dc94260441a47f)
![{\displaystyle W\cdot \operatorname {sinc} [W(n+a)]}](https://wikimedia.org/api/rest_v1/media/math/render/svg/d4185f56193a63b426f87329e9d7c0d1ae50fced)
![{\displaystyle {\frac {W}{(n+a)}}\left\{\cos[\pi W(n+a)]-\operatorname {sinc} [W(n+a)]\right\}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/f7d4cd8e41d9e483f5d90da18cff3661d914ce9b)
![{\displaystyle {\frac {1}{\pi n^{2}}}[(-1)^{n}-1]}](https://wikimedia.org/api/rest_v1/media/math/render/svg/4114640d8ab7e22e07fe380574400fb036941530)
![{\displaystyle {\frac {C(A+B)}{2\pi }}\cdot \operatorname {sinc} \left[{\frac {A-B}{2\pi }}n\right]\cdot \operatorname {sinc} \left[{\frac {A+B}{2\pi }}n\right]}](https://wikimedia.org/api/rest_v1/media/math/render/svg/38083aff1d4f22b4848dfafdc988b43142f7c472)