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x ( t ) = 0 + k = 1 k odd 13 4 k π sin ( 2 π k t ) .

These are the first 8 terms in the Fourier series of the periodic square wave shown in [link] .

The desired waveform for the synthesizer experiment.

Run the model by selecting Start under the Simulation menu. A graph will pop up that shows the synthesized square wave signaland its spectrum. This is the output of the Spectrum Analyzer . After the simulation runs for a while,the Spectrum Analyzer element will update the plot of the spectral energy and the incoming waveform.Notice that the energy is concentrated in peaks corresponding to the individual sine waves.Print the output of the Spectrum Analyzer .

You may have a closer look at the synthesized signal by double clicking on the Scope1 icon. You can also see a plot of all the individual sine wavesby double clicking on the Scope2 icon.

Synthesize the two periodic waveforms defined in the "Synthesis of Periodic Signals" section of the background exercises. Do this by setting the frequency, amplitude, and phaseof each sinewave generator to the proper values. For each case, print the output of the Spectrum Analyzer .

Hand in plots of the Spectrum Analyzer output for each of the three synthesized waveforms.For each case, comment on how the synthesized waveform differs from the desired signal, and on the structureof the spectral density.

Modulation property

Simulink model for the modulation experiment.

Double click the icon labeled Modulator to bring up a system as shown in [link] . This system modulates a triangular pulse signal with a sine wave.You can control the duration and duty cycle of the triangular envelope and the frequency of the modulating sine wave.The system also contains a spectrum analyzer which plots the modulated signal and its spectrum.

Generate the following signals by adjusting the Time values and Output values of the Repeating Sequence block and the Frequency of the Sine Wave . The Time values vector contains entries spanning one period of the repeating signal.The Output values vector contains the values of the repeating signal at the times specifiedin the Time values vector. Note that the Repeating Sequence block does NOT create a discrete time signal. It creates a continuous time signalby connecting the output values with line segments. Print the output of the Spectrum Analyzer for each signal.

  1. Triangular pulse duration of 1 sec; period of 2 sec; modulating frequency of 10 Hz (initial settings of the experiment).
  2. Triangular pulse duration of 1 sec; period of 2 sec; modulating frequency of 15 Hz.
  3. Triangular pulse duration of 1 sec; period of 3 sec; modulating frequency of 10 Hz.
  4. Triangular pulse duration of 1 sec; period of 6 sec; modulating frequency of 10 Hz.

Notice that the spectrum of the modulated signal consists of of a comb of impulses in the frequency domain,arranged around a center frequency.

Hand in plots of the output of the Spectrum Analyzer for each signal. Answer following questions:1) What effect does changing the modulating frequency have on the spectral density?2) Why does the spectrum have a comb structure and what is the spectral distance between impulses? Why?3) What would happen to the spectral density if the period of the triangle pulse were to increase toward infinity? (in the limit)

Questions & Answers

Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
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
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
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
why?
Adin
what school?
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
hi
Loga
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Purdue digital signal processing labs (ece 438). OpenStax CNX. Sep 14, 2009 Download for free at http://cnx.org/content/col10593/1.4
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