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Figure 1. Required parameters.
Data length as type int Number of sinusoids as type int. Max value is 5.List of sinusoid frequency values as type double. List of sinusoid amplitude values as type double.

The length of the two lists

The number of values in each of the lists must match the value for the number of sinusoids. Also, you must not allow blank lines at the end of the data in thefile.

Frequency value specifications

Each frequency value is specified as a type double value representing a fractional part of the sampling frequency.

(For example, a double value of 0.5 specifies one-half the sampling frequency, or the Nyquist folding frequency. A double value of 2.0 specifiesa frequency that is twice the sampling frequency.)

Figure 2 shows the contents of the file named Dsp029.txt that I used to produce the output shown in Figure 3 . I will discuss that output later.

Figure 2. Actual parameter values.
50.0 50.03125 0.06250.125 0.250.5 9090 9090 90

The plotting program named Graph06

The plotting program that is used to plot the output data from this program requires that the program implement GraphIntfc01 . I discussed that interface in the module titled Plotting Engineering and Scientific Data using Java . For example, the plotting program named Graph06 can be used to plot the data produced by this program. When it is used, the program is executed and its output is plotted byentering the following at the command line prompt:

java Graph06 Dsp029

Program output

Figure 3 shows the output produced by running the program named Dsp029 with the parameters shown in Figure 2 and then adjusting the xMax parameter in thetextbox at the bottom of the display.

Figure 3. Program output for five sinusoids.
missing image

Five horizontal plots

Each of the five horizontal plots in Figure 3 shows a sampled sinusoid. Each of the vertical bars represents one sample value for a given sinusoid.

If you examine the frequency values in Figure 2 carefully, you will see that they represent the sampling frequency divided by the factors 32, 16, 8, 4, and2. Thus, the last frequency value is the Nyquist folding frequency and the first four frequency values are related to that frequency by multiples of two.

The horizontal plot at the top of Figure 3 is a reasonably well defined cosine wave. The horizontal plot at the bottom of Figure 3 shows the result of having exactly two samples per cycle of the sinusoid. Using this plottingscheme, the sampled sinusoid is represented as a square wave. Using another plotting scheme (such as that used in the program named Graph03 ) the sampled sinusoid at the bottom would be represented as a triangular wave.

An upper frequency limit

Regardless of the plotting scheme used, it should be obvious that a set of uniform samples cannot possibly represent frequencies higher than one-half thesampling frequency because then there would be less than one sample per cycle of the sinusoid.

The Nyquist folding frequency

Now I will show you why the frequency at one-half the sampling frequency is referred to as the folding frequency using the new set of frequency values shownin Figure 4 .

Questions & Answers

How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
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Adin
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Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
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it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
How can I make nanorobot?
Lily
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
how can I make nanorobot?
Lily
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
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Smarajit Reply
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Source:  OpenStax, Digital signal processing - dsp. OpenStax CNX. Jan 06, 2016 Download for free at https://legacy.cnx.org/content/col11642/1.38
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