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You will implement a fourth-order, elliptical, low-pass infinite impulse-response (IIR) filter as a cascade of two second-order sections.

Implementation

On the DSP, you will implement the elliptic low-pass filter designed using the ellip command from IIR Filters: Filter-Design Exercise in MATLAB . You should not try to implement the notch filter designed in IIR Filtering: Filter-Coefficient Quantization Exercise in MATLAB , because it will not work correctly when implemented using Direct Form II. (Whynot?)

To implement the fourth-order filter, start with a single set of second-order coefficients and implement a singlesecond-order section. Make sure you write and review pseudo-code before you begin programming. Once your single second-order IIR is working properly you canthen proceed to code the entire fourth-order filter.

Large coefficients

You may have noticed that some of the coefficients you have computed for the second-order sections are larger than 1.0in magnitude. For any stable second-order IIR section, the magnitude of the "0" and "2" coefficients( a 0 and a 2 , for example) will always be less than or equal to 1.0. However, the magnitude of the "1" coefficient can beas large as 2.0. To overcome this problem, you will have to divide the a 1 and b 1 coefficients by two prior to saving them for your DSP code. Then, in your implementation, you will have tocompensate somehow for using half the coefficient value.

Repeating code

Rather than write separate code for each second-order section, you are encouraged first to write one section, thenwrite code that cycles through the second-order section code twice using the repeat structure below. Because the IIRcode will have to run inside the block I/O loop and this loop uses the block repeat counter ( BRC ), you must use another looping structure to avoid corrupting the BRC .

You will have to make sure that your code uses different coefficients and states during the second cycle ofthe repeat loop.

stm (num_stages-1),AR1 start_stage ; IIR code goes here banz start_stage,*AR1-

Gain

It may be necessary to add gain to the output of the system. To do this, simply shift the output left (which can be doneusing the ld opcode with its optional shift parameter) before saving the output to memory.

Grading

Your grade on this lab will be split into three parts:

  • 1 point: Prelab
  • 4 points: Code. Your DSP code implementing the fourth-order IIR filter is worth 3 points and the MATLABexercise is worth 1 point.
  • 5 points: Oral quiz. The quiz may cover differences between FIR and IIR filters, the prelab material, and theMATLAB exercise.

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
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Source:  OpenStax, Ece 320 - spring 2003. OpenStax CNX. Jan 22, 2004 Download for free at http://cnx.org/content/col10096/1.2
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