Re: Filtering

rajgerman wrote:
Hey

Once I have filtered out the frequencies I don't want plus ifft the
results then I will compare them to the data collected from the eye.

I'm trying to create a vector with zeros and ones but finding it
difficult. So far I have done the following:

V = ones(1,88200);
f = -44100/2:1/2:44100/2-1/2;

I have now described the x-axis of V in frequency terms. Now how do I
convert the 1's outside -5000Hz and 5000Hz from V into 0's??

So then I'm able to multiply the result to my ffted data as stated in the
previous posts. I know some of you suggest that this is not the best
method but I'm just trying out different ways. Please bear in mind I'm
just a beginner to DSP and MATLAB.


Oho! Before, you wrote 5 Hz. Now it appears that 5 Hz was a mistake, and it should have been 5 KHz. That changes many of the numbers in Fred's response to you. It see the frequency response of your brick-wall filter, you will need to start with a signal that has uniform response initially. A pseudorandom bit stream will serve.

Be warned: the response above 5 KHz will be quite large at some frequencies. This will show best on a logarithmic (decibel) vertical scale. It might also be instructive to use a squarish pulse (corners softened to remove frequencies above 20 KHz) and observe the shape of the filtered result.

You once wrote, "I'm not too good with matlab so I'm trying to find the most easiest way. I also don't want to use the signal processing tools." You can't learn to drive a car without learning also where the pedals are and what they do.

Jerry
--
Engineering is the art of making what you want from things you can get.
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