Analyses on single point data signal

[Getwonder]

Hello,

A good achievement. The last problem has been resolved.

It was due to the addition of a 10ms delay in the consumer loop.

Now i am working on Filter Design to remove the noise. Which was the original task.

Will update you about the result.

[Getwonder]

Hello,

I am sharing you some basic problems that are still unsolved.

1- i cant get the high frequency waveform to be displayed, as was previously a problem.

2- The data that is acquired is stored in the buffer and is not displayed on the graph in real time. Even if the delay of this loop is also removed. Therefore the buffer size goes long and if their is a change in the original signal it is displayed at a very time delay.

T.C

[Eric_L]

Hello T.C.,

I noticed there have been a lot of revisions of your code to get different aspects of the code to function properly. Can you post a revised screen shot of your code to ease the trouble shooting process?

Eric

[Getwonder]

Hello Eric, and thanks for joining us.

As you asked, the VI I have posted previously is the latest of my circuitry.

I am sending some pics of the results of Signals received of higher frequencies.

[johnsold]

Those images look very much as I would expect for a sampling rate of about 350 Hz.  If you change the plots to show dots at the actual data points, you will see how few points per cycle are in the data at the higher signal frequencies.  I estimate that you are getting about 7 samples in the first cycle of the 50 Hz signal.  One cycle at 50 Hz is 20 ms.  Divide that by 7 and take the reciprocal: 350 Hz sampling rate.

Your effective sampling rate is limited by the communications.

Lynn

[Eric_L]

T.C.,

The wiring for the stop is done in a very strange manner. The way it is wired seems to imhibit the data flow and prevents the waveform graph from running. If you run the code in highlight execution, you will see what I mean. Consider disconnecting the Producer and Comsummer loops and use local or shared variables for the stop command.

Eric

[Getwonder]

Thanks Johnsold

do you think that transmitting data at a higher speed would solve this problem.

Also that could it bring any problem in the project.

Take Care

[johnsold]

Higher sampling rates will give better waveform fidelity at higher frequencies.  Whether it will create any new problems depends on your overall system.  Can you communicate faster without losing data?  Can you handle the larger data sets?

Does it really matter?  If you know the signal is sinusoidal, you do not need to sample enough to display a clean waveform.  All you need is enough to determine frequency, phase, and amplitude.  When you know those three values you can calculate the value of the waveform at any time mathematically.  What are you doing with the data after you get it ?

Lynn

[Getwonder]

Thanks very much.

As long as sampling rate is concerned, i have connected Waveform chart exactly at the point the data is received i.e at the buffer point and it also displays the same output so i think that Increasing the sampling rate would not effect anymore.

The second and the most important thing.

I want to apply different processing techniques on it and want to display and send it.

At the moment, i am working on the processing side.

And my next step would be Filtering the received signal.

Since i have tried Analog filters and don't found them accurate enough to remove noise. I am trying to remove it digitally and more specifically through Labview.

So i would be working on the filter design and if you have any good idea to design a bandstop filter, than pls share.

[Getwonder]

Hello Eirc,

Thanks for your reply

As long as that loop is concerned which is waiting for a value 5 to arrive is just a waiting loop created to check whether the hardware has got ON or not.

And the other stages than works after it.

T.C