Need to get travel time of each echo

[AMI007]

Hi,  

I want to calculate the travel time of an echo.  

The data I have, is a triggered pulse and 4 echoes in a single graph at different  time intervals.  

Now, I want to calculate the travel time of each echo from triggered pulse start.  

Method I want to use,  

1. Calculate first trigger point.

2. Get the end of waveform and gate the data.

3. Again repeat step 1 and 2 , to get first trigger point.  

Is there any way to calculate the point where waveform ends or is almost constant?  

Or, is there any other method to calculate travel times.  

I am new to LabVIEW.Please help.  

Thanks, Amit

[Zwired1]

Answers to your questions will depend on how you have your acquisition set up. 

I general, I would expect that you'd set up the system to wait for a loud noise and then take some finite amount of samples (e,g, 100k samples at 10kHz) that will be sure to capture the echos. In this scenario you will alway get the same number of samples. 

You can get the amplitudes of the data by using "get waveform components.vi" or "convert from dynamic data" and then use "threshold 1D array" to find the rising edge of the echo peaks.