The module will provide analysis and examples of how a continuous-time signal is converted to a digital signal and processed.
Dt processing of ct signals
Analysis
where we know that
and
is the frequency response of the DT LTI system.
Also, remember that
So,
where
and
are CTFTs and
and
are DTFTs.
OR
Therefore our final output signal,
, will be:
Now, if
is bandlimited to
and we use the usual lowpass reconstruction filter in the
D/A,
:
Then,
Summary
For bandlimited signals sampled at or above the Nyquist
rate, we can relate the input and output of the DSP systemby:
where
Note
is LTI if and only if the following two
conditions are satisfied:
is LTI (in DT).
is bandlimited and sampling rate equal to or
greater than Nyquist. For example, if we had a simplepulse described by
where
. If the sampling period
,
then some samples might "miss" the pulse while othersmight not be "missed." This is what we term
time-varying behavior .
Unfortunately, in real-world situations electrodes also pick
up ambient 60 Hz signals from lights, computers,
etc. . In fact, usually this "60 Hz noise"
is much greater in amplitude than the EKG signal shown in
.
shows the EKG signal; it is barely noticeable
as it has become overwhelmed by noise.
Dsp solution
Sampling period/rate
First we must note that
is
bandlimited to60 Hz.
Therefore, the minimum rate should be 120 Hz. In order toget the best results we should set
.
Digital filter
Therefore, we want to design a digital filter that will
remove the 60Hz component and preserve the rest.
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Wine
discuss the biological phenomenon and provide pieces of evidence to show that it was responsible for the formation of eukaryotic organelles in an essay form
advantage of electronic microscope is easily and clearly while disadvantage is dangerous because its electronic. advantage of light microscope is savely and naturally by sun while disadvantage is not easily,means its not sharp and not clear
Abdullahi
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Abdullahi
is like gone fail us
DENG
cells is the basic structure and functions of all living things
A scanning electron microscope (SEM) is ideal for situations requiring high-resolution imaging of surfaces. It is commonly used in materials science, biology, and geology to examine the topography and composition of samples at a nanoscale level. SEM is particularly useful for studying fine details,