Môn họcMôn học
TÍN HIỆU VÀ HỆ THỐNGTÍN HIỆU VÀ HỆ THỐNG
Giảng viên: PGS. TS. Huỳnh Thái Hoàng
Khoa Điện – Điện Tử
Đại học Bách Khoa TPHCM
Email: hthoang@hcmut edu vn
Email:
hthoang@hcmut
.
edu
.
vn
Homepage: www4.hcmut.edu.vn/~hthoang/
1
Chương 3Chương 3
BIỂU DiỄN TÍN HIỆU TUẦN HOÀN DÙNG BIỂU DiỄN TÍN HIỆU TUẦN HOÀN DÙNG
CHUỖI FOURIERCHUỖI FOURIER
2
Biểdiễtí hiệbằtậtí hiệt i
Nội dung chương 3Nội dung chương 3
Biể
u
diễ
n
tí
n
hiệ
u
bằ
ng
tậ
p
tí
n
hiệ
u
t
rực g
i
ao
Chuỗi Fourier lượng giác
Ch ỗiF i hà ũhứ
Ch
u
ỗi
F
our
i
er
hà
m m
ũ
p
hứ
c
Đáp ứng của hệ thống LTIC với tín hiệu tuần hoàn
3
Biểu diễn tín hiệu bằng Biểu diễn tín hiệu bằng
tập tín hiệu trực giaotập tín hiệu trực giao
4
Biểu diễn gần đúng vectorBiểu diễn gần đúng vector
f
e
f
1
e
f
2
e
ể
x
xc
x
xc
1x
xc
2
excf
Bi
ể
u diễn vector theo vector :
f
x
Khi min:
1
|| e
xcf
x
f
x
c
.
||
1
2
với
cos||.||. xfxf
Khi đó:
5
Hai vector trực giao: 0. xf
![Bài giảng Kỹ thuật số: Chương 2 - Huỳnh Việt Thắng [Mới Nhất]](https://cdn.tailieu.vn/images/document/thumbnail/2026/20260420/hoatrami2026/135x160/66851776745650.jpg)
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