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Setting the Sine Wave to 300 Hz

Make a note of the accuracy of the model.

Changing the frame sizes

Increase the Samples per frame to 1024 in both the “Sine Wave” and the “Random Source” Blocks.

Adjusting Frame Size for Sine Wave
Adjusting the Frame Size for the Random Source

Run the model again.

Question: How does this change to the frame size affect performance?

Setting the delay value

Click on the “Delay” Block. Change the number of Delay (samples) to 50.

Setting the Delay (samples)

Run the model again and make a note of the accuracy of the measurement.

Change Delay (samples) The Delay (samples) should be smaller than the frame size, otherwise the frames do not overlap. to 12 and run the model again.

Question: How does the value of delay (samples) affect the accuracy of the model?

Changing the amount of noise present

Reload the original model to restore the initial settings.

Change the amount of Gain to make the gain 0.10 (10% noise).

Changing the Amount of Noise Present

Run the model and make a note of the accuracy of the measurements. Repeat, but this time, use a gain of 0.01 (1% noise).

Question: Does the algorithm work better for high signal-to-noise ratios or for low signal-to-noise ratios? Make a note of the answer.

Changing the sampling frequency

Change the sample time in both the “Sine Wave” and the “Random Noise” blocks to 48000 Hz.

Changing the Sine Wave Sample Time
Changing the Random Source Sample Time

Run the model.

Question: Does the model produce better results with 8000Hz sampling or 48000 Hz sampling? Make a note of the answer.

The fully optimized simulation

You should now know what are the optimum parameters for the simulation.

Set these parameters and run the model.

Summary of simulation

You have now run the signal-to-noise ratio model and should be aware of the best settings for consistency of measurements, delay and sampling frequency.

You are now ready to go to the C6713 DSK Model.

Real-time model for ti c6713 dsk

Texas instruments c6713 dsk setup

Texas Instruments C6713 DSK Setup

Alternatively, you can use computer loudspeakers.

Starting code composer studio

There are several stages required in order to implement the Signal-to-Noise measurement. These are now described.

Starting up code composer studio

Start Code Composer Studio for C6713 DSK and use Debug ->Connect

Startup Screen for Code Composer Studio (CCS)

The texas instruments c6713 dsk model

You will now use the knowledge you have gained during the PC Simulation to produce an optimized version of this algorithm for use with the Texas Instruments C6713 DSK.

Opening the c6713 dsk model

Open the SignalToNoiseDSK6713.mdl.

The parent is shown in Figure 15.


Double click on the “function()” block.

Viewing the signal-to-noise measurement algorithm

The details of the C6713 Algorithm are shown in Figure 16.

Audio Noise Gate

Setting the sampling rate and frame size

Double-click on the “Mic In C6713 DSK ADC” block.

Set the Sampling rate (Hz) and Samples per frame fields to the best value you found while carrying out the Simulation. The values may be different to those written here.

Setting the Sampling Rate and Frame Size

Setting the delay size

Double-click on the “Delay” block. Set the Delay (samples) to the best value found during simulation. The value will not be 999!

Setting the Delay Size

Returning to the parent system

From the Toolbar, select the “Up Arrow” icon. This returns you to the next higher level.

Returning to the Parent System

Building the model

Selecting real-time workshop

Select Tools ->Real-Time Workshop ->Build Model.

Building the Model

The completed model running on code composer studio

From the folders on the left, select the source code for the project.

The Completed Model Running in Code Composer Studio

Different settings on the c6713 dsk

Microphone straight through to loudspeakers

To check out the microphone and loudspeakers, set the DIP switches on the C6713 DSK as follows:

Switch Position 0

The microphone is fed directly to the loudspeakers. There is no noise gate.

Switch position for the audio noise gate

To run the Audio Noise Gate, set the DIP switch to 1.

Switch Position 1 for Audio Noise Gate

Note that when you are not speaking, there is no audio output at all – just silence.

Modifying the model

The next stage is to modify the model. You can change the smoothing filter. If the filter is too long, the delay will be noticeable.

Changing the filter type

Double-click on the “Lowpass” block. Change the Order to a value other than 10.

Changing the Number of Filter Elements

Re-building the model

Select Tools ->Real-Time Workshop ->Build Model.

Re-building the Model

Running the updated model

Run the updated model and listen to the effect on the audio noise gate.

Some things to try

You may wish to experiment with different settings. Here are some suggestions.

Add an input filter

While running the Simulation, you will have noticed that the Signal-to-Noise Algorithm works better on some frequencies than others.

Add the appropriate filter to select only the frequencies where the algorithm works well.

Process stereo inputs

Change the input from “Microphone” to “Stereo Line Input”.

Add a second channel to make the processing stereo.

Best signal selection

When stage 3.2 has been completed, modify the model so that the output is the better of the two stereo inputs.

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Questions & Answers

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.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
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.
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
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
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
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
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.
what is the actual application of fullerenes nowadays?
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.
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.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
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