ASN7 - Sampled half of signal: Difference between revisions

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Can you retrieve an original signal from a sample of range <math> \frac{1}{2}f>f_s>f \!</math>?
Suppose you sampled only half of the signal can you do something to recover the whole original signal again?






A rule of thumb for proper sampling is to have a sample range that is slightly greater than the range of the signal. Lets imagine that from our sampling we split the positive and the negative part of the signal. So now we have the negative half repeated on the negative axis and the positive half all along the positive axis.
A rule of thumb for proper sampling is to sample range slightly greater than the range of the signal. Suppose however,you sampled only half of the signal can you do something to recover the whole original signal again?


1. Lets imagine that from our the result of our sampling we measured the positive and the negative part of the signal seperately. [Assume the original signal was centered at zero such that <math> f_{tot}= f_{-}+f_{+}]</math>
the trick now is to re-sample at a frequency that will place the negative and positive half side by side. When found that frequency use it sample again. After doing this you should have a number of copies

of the original signal. To get just one apply a band pass filter.

So we have repeated on the negative axis the -f and the positive axis +f.

The trick now is to re-sample at a frequency that will place the negative and positive half side by side.


2. Find the right frequency and sample again.


The result of this second sampling are a number of copies of the original signal <math>nf_{tot} </math> .


3. finally, to get just one copy of the original signal apply a band pass filter.

Revision as of 12:31, 20 December 2009

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Can you retrieve an original signal from a sample of range ?


A rule of thumb for proper sampling is to sample range slightly greater than the range of the signal. Suppose however,you sampled only half of the signal can you do something to recover the whole original signal again?

1. Lets imagine that from our the result of our sampling we measured the positive and the negative part of the signal seperately. [Assume the original signal was centered at zero such that


So we have repeated on the negative axis the -f and the positive axis +f.

The trick now is to re-sample at a frequency that will place the negative and positive half side by side.


2. Find the right frequency and sample again.


The result of this second sampling are a number of copies of the original signal .


3. finally, to get just one copy of the original signal apply a band pass filter.