HAN HAN DAN WIDI MEREKA KEMBARAN CUY ADEK KAKAK ATUH
IrlanMalik
13 views
39 slides
May 30, 2024
Slide 1 of 39
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
About This Presentation
HAN HAN HAN HAN WIDIWIDIWDIWDIWDIWDIDIW
Size: 10.76 MB
Language: en
Added: May 30, 2024
Slides: 39 pages
Slide Content
Ashutosh Dhekne CS 8803 - MCI Signal Processing III
What does the Fourier Matrix provide us? Time Domain Signal Freq Domain 0Hz 1Hz 2Hz 3Hz 4Hz 5Hz 6Hz 7 Hz
What does the Fourier Matrix provide us? Time Domain Signal Freq Domain 0Hz 1Hz 2Hz 3Hz 4Hz 5Hz 6Hz 7 Hz No DC Component Signal is symmetric above and below the 0 amplitude
What does the Fourier Matrix provide us? Time Domain Signal Freq Domain 0Hz 1Hz 2Hz 3Hz 4Hz 5Hz 6Hz 7 Hz Frequency domain vector is symmetric around 4Hz
What does the Fourier Matrix provide us? Time Domain Signal Freq Domain 0Hz 1Hz 2Hz 3Hz 4Hz 5Hz 6Hz 7 Hz Only components are 1Hz and 3Hz (non-zero values in the frequency domain)
What does the Fourier Matrix provide us? Time Domain Signal Freq Domain 0Hz 1Hz 2Hz 3Hz 4Hz 5Hz 6Hz 7 Hz 1Hz is twice as dominant as 3Hz frequency
Example: Graphic Equalizer
How is such a transformation performed? Time Domain Signal
Time Domain to Frequency Domain
Time Domain to Frequency Domain Another Basis
Basis in the Time Domain
Basis in Frequency Domain
Time Domain to Frequency Domain =
Time Domain to Frequency Domain =
Time Domain to Frequency Domain =
Time Domain to Frequency Domain
Time Domain to Frequency Domain Check this at home!
What if the signal has higher frequencies?
What if the signal has higher frequencies?
What if the signal has higher frequencies? Time Domain Signal
What if the signal has higher frequencies? Time Domain Signal Freq Domain 0Hz 1Hz 2Hz 3Hz 4Hz 5Hz 6Hz 7 Hz
What if the signal has higher frequencies? Time Domain Signal Freq Domain 0Hz 1Hz 2Hz 3Hz 4Hz 5Hz 6Hz 7 Hz Does this signal have a 2Hz component?
Does this FD signal produce the same TD signal? Time Domain Signal Freq Domain 0Hz 1Hz 2Hz 3Hz 4Hz 5Hz 6Hz 7 Hz Does this signal have a 2Hz component?
In fact, it is ambiguous! Which of these is the correct analog signal?
In fact, it is ambiguous! Time Domain Signal Freq Domain 0Hz 1Hz 2Hz 3Hz 4Hz 5Hz 6Hz 7 Hz
In fact, it is ambiguous! Time Domain Signal Freq Domain 0Hz 1Hz 2Hz 3Hz 4Hz 5Hz 6Hz 7 Hz There can exist infinitely many analog signals that will produce the same discrete frequency domain signal and the same discrete time domain signal!
Aliasing
Aliasing Aliasing is an effect that causes different signals to become indistinguishable (or aliases of one another) when sampled.
Aliasing Aliasing is an effect that causes different signals to become indistinguishable (or aliases of one another) when sampled. It also often refers to the distortion or artifact that results when a signal reconstructed from samples is different from the original continuous signal.
Aliasing : Matlab examples
Nyquist Frequency / Folding Frequency Harry Nyquist Feb 7, 1889 - Apr 4, 1976
The concept of filters
FFT as frequency increases
The difference between sine and cosine Time Domain Signal Freq Domain 0Hz 1Hz 2Hz 3Hz 4Hz 5Hz 6Hz 7 Hz
The difference between sine and cosine Time Domain Signal Freq Domain 0Hz 1Hz 2Hz 3Hz 4Hz 5Hz 6Hz 7 Hz
FFT with change in phase
Fourier Matrix in the more general form 0Hz 1Hz 2Hz 3Hz 4Hz 5Hz 6Hz 7Hz What if we divide the circle into N parts instead of 8?
Fourier Matrix in the more general form 0Hz 1Hz 2Hz 3Hz 4Hz 5Hz 6Hz 7Hz What if we divide the circle into N parts instead of 8? How will the matrix change?
0Hz 1Hz 2Hz 3Hz 4Hz 5Hz 6Hz 7Hz How will the matrix change? Becomes N Extends to N-1 Extends to N-1