Dealing with chirp signal

[rashp8]

Hi,

So I have been facing this problem for quite sometime now. I am generating a chirp signal at 270-330khz, sample rate 2Msps, number of samples 10k, total running time 5milliseconds. Then transmitting it at the same rate and number of samples on the DAQ. The waveforms on the front panel are enclosed herein. I am receiving this at a lower sample rate of DAQ i.e.135khz and number of samples 675. While everything else is right, I don't understand why my signal is continuously changing and also there is a dip in frequency spectrum. I have enclosed the video of the output. 

Hope I have made myself clear.

Oh, and I am using continuous acquisition for both transmission and reception.

P.S.-The video file is too large so I am attaching screenshots. 

[GerdW]

Hi rashp,

I am generating a chirp signal at 270-330khz …

I am receiving this at a lower sample rate of DAQ i.e.135khz

You surely have heard of Nyquist and Shannon and something called "aliasing"?

[rashp8]

Hi GerdW,

Yes sir I am very much aware of it. It's just I am not sure how to explain the problem. Actually after acquiring the signal in continuous mode it's continuously changing. I want it to stop for a considerable amount. Come to it I am attaching a file I want you to help me with. The signal is repeating every 5 ms and I am required to display it for only 5 milloseconds and then stop it for next 95 milliseconds and then again display it for next 5 and so on. Can you suggest or build a vi that does this operation.