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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 do they get the third part x = (32)5/4
kinnecy Reply
can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
ninjadapaul
20/(×-6^2)
Salomon
okay, so you have 6 raised to the power of 2. what is that part of your answer
ninjadapaul
I don't understand what the A with approx sign and the boxed x mean
ninjadapaul
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
Salomon
I'm not sure why it wrote it the other way
Salomon
I got X =-6
Salomon
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
ninjadapaul
oops. ignore that.
ninjadapaul
so you not have an equal sign anywhere in the original equation?
ninjadapaul
Commplementary angles
Idrissa Reply
hello
Sherica
im all ears I need to learn
Sherica
right! what he said ⤴⤴⤴
Tamia
hii
Uday
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
Kim
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Al
y=10×
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
is it 3×y ?
Joan Reply
J, combine like terms 7x-4y
Bridget Reply
how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
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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