how to retain the pulses of a specific duration and delete the rest ?

 i have a vetor which has pulses of different durations. I want to capture the pulses with a specific duration and delete the rest. Also the captured pulses should be displayed in the same time interval as in the  original vector .kindly help me with a matlab code.

Answer 1

[Kushagr Gupta]

I understand that you wish to detect pulse widths along with their time-stamps and threshold the signal based on width.

The function 'pulsewidth' can be very useful in this regard as it outputs the widths and time information as well. Documentation for the same can be found at :

https://www.mathworks.com/help/signal/ref/pulsewidth.html

Once the widths and start-time of each pulse is known it can be used to capture wanted pulses. Following code snippet shows how 'pulsewidth' can be used:

>>A = rand(100,1);
>>B = A > 0.5; % creating a random signal of 1's and 0's
>>[wid, P_start, P_end, midL] = pulsewidth(double(B));
>>PulseInd=P_start+0.5 % index where a pulse begins

Thus "PulseInd" contains the index where a pulse begins and "wid" contains the width of that particular pulse. Using this information the signal can be thresholded and desired result obtained.