What is an anti aliasing filter? Why is it required?
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Answer / mani_drvsv
Anti aliasing filter reduces errors due to aliasing. If a
signal is sampled at 8 kS/S, the max frequency of the input
should be 4 kHz. Otherwise, aliasing errors will result.
Typically a 3.4kHz will have an image of 4.6 khz, and one
uses a sharp cut off filter with gain of about 1 at 3.4kHz
and gain of about 0.01 at 4.6 kHz to effectively guard
against aliasing. Thus one does not quite choose max
frequency as simply fs/2 where fs is sampling frequency.
One has to have a guard band of about 10% of this fmax, and
chooses max signal frequency as 0.9*fs/2
| Is This Answer Correct ? | 31 Yes | 4 No |
Answer / harshgandhi126
If we sample the signal below the Nyquist Frequency then
aliasing occurs. So, to remove this aliasing we use filter
before sampling the signal.This filter will not allow the
freuency greater than the Nyquist Frequency.
| Is This Answer Correct ? | 20 Yes | 0 No |
Answer / jilani
anti aliasing filter is a low pass filter which is used to
remove the high frequency distortions in the i/p signal
| Is This Answer Correct ? | 3 Yes | 0 No |
Answer / guest
Anti aliasing filter reduces errors due to aliasing. If a
signal is sampled at 8 kS/S, the max frequency of the input
should be 4 kHz. Otherwise, aliasing errors will result.
Typically a 3.4kHz will have an image of 4.6 khz, and one
uses a sharp cut off filter with gain of about 1 at 3.4kHz
and gain of about 0.01 at 4.6 kHz to effectively guard
against aliasing. Thus one does not quite choose max
frequency as simply fs/2 where fs is sampling frequency.
One has to have a guard band of about 10% of this fmax, and
chooses max signal frequency as 0.9*fs/2
| Is This Answer Correct ? | 2 Yes | 0 No |
Answer / nuts
anti aliasing filter band limits the input signal such that there is no frequency component higher than W Hz (say) in input signal, thus reduces the chances of aliasing after sampling.
| Is This Answer Correct ? | 1 Yes | 0 No |
Answer / guest
The anti aliasing filter is second id of any person.Its halp
fof know the person.so we can say that its very impotant.
| Is This Answer Correct ? | 0 Yes | 24 No |
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