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Iir filter design via the bilinear transformation

LabVIEW DSP allows the user to implement standard IIR digital filters designed using a filter designsupplemental program, called Digital Filter Design Toolkit. The DFD toolkit is an add-on module to LabVIEW (not LabVIEW Embedded). Thismodule allows the user to design complex filters, save them and implement them using LabVIEW DSP.

New Block Diagram with DFD Filter
  • Go to the Functions palette and add the DFD Filter Express VI to your existing Block Diagram: Functions»SignalProcessing»Filters»DFD Filter
  • Wire the Express VI as shown in Figure 6. The output of the Add function is the input “Signal” of the ExpressVI and the “Filtered Signal” goes into the Analog Output. Set the function generator’s signal to a frequency of 500 Hz.
  • Follow the steps below to implement alowpass filter that will be implemented on the DSP. Launch LabVIEW by going to Start»All Programs»National Instruments»LabVIEW7.1»LabVIEW. Let’s try to understand what is happening. We first launched LabVIEW Embedded Edition which allowed us to target theDSP hardware and run our program. Now, we are launching LabVIEW, not LabVIEW Embedded Edition. The program you built earlier shouldstill be open. We will use the Digital Filter Design Toolkit available in the LabVIEW environment to design the filter.
  • Create a blank VI (New»Blank VI).
  • Switch to the Block Diagram and drop a DFD Classical Filter Design on the Block Diagram: It is in Functions»AllFunctions»Digital Filter Design»Filter Design»DFD Classical Filter Design.
  • In the DFD Classical Filter Design Express VI, enter the following settings:
    • Filter Type: Lowpass
    • Sampling Frequency: 16000 Hz
    • Passband Edge Frequency: 1000 Hz
    • Passband ripple: 3 dB (standard for Butterworth filters)
    • Stopband Edge Frequency: 1500 Hz
    • Minimum stopband attenuation 20 dB
    • Design Method: Butterworth
    Leave the other settings to their default values.
    DFD Classical Filter Design Configuration Window
  • Check the graph to the left to make sure the filter response appears as expected and click “OK” to set theconfigurations.
  • Some filter parameters are described below:
    • Sampling Frequency – self-explanatory. Make sure to set it to the sampling frequency that you plan on using!
    • Center Frequency – (not used for lowpass filters). Set this to the middle frequency of the passband for Bandpass/Highpassfilters or the middle frequency of the stopband for Bandstop filters.
    • Bandwidth – Set this to the frequency width of the passband (stopband for Bandstop filters). Recall that Lowpass filters have alower passband frequency of 0 Hz and that Highpass filters has an upper passband frequency of Fs/2.
    • Stopband Attenuation – Set this to the desired attenuation in dB at the edge of the stopband. For Bandstop filters, thisparameter must be negative (because the stopband is really the passband). For all other filter types, this parameter must bepositive.
    • Passband Ripple – Set this to the desired attenuation (in dB) at the edge of the Passband. For Butterworth filters, the standard(but not required) value to use is 3 dB.
    • Filter Order N – Set this to the desired filter order. However, after you press the Apply button, the program calculateswhich filter order you need to meet the given specs. For most applications, then, you can put any number here and then change itto the necessary value when instructed. There may be some situations, however, when you want to force the filter order to besome set value. In this case, the desired specifications may not be met.
    Regarding calculation of filter order N: This program uses the same design equations that we use in EE 453. For IIR filters, the program automatically does prewarping.
  • Build the following Block Diagram to save the filter settings: Drop a “DFD Save to File” VI on the BlockDiagram. This VI is located at Functions»All Functions»Digital Filter Design»Utilities»DFD Save to File. Wire the Block Diagram asshown in Figure 6.
    Filter Design
  • Run the filter design VI you just built. When prompted to save your design, navigate to your folder and saveyour filter under any chosen name. Save and close this VI.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
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.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
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
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
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
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
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Source:  OpenStax, Fundamentals of digital signal processing lab. OpenStax CNX. Jan 03, 2006 Download for free at http://cnx.org/content/col10303/1.5
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