Hi Karthik, the website attached has a detailed guide on the process of decoding ADS-B packets. To generate your own packets it is simply the same process in reverse. I hope this is helpful.

http://adsb-decode-guide.readthedocs.org/en/latest/

Hello,

You might consider the test data available here: https://github.com/junzis/pyModeS/tree/master/tests

BR,

Y.