ye it is a vehicle mounted radio frequency (gsm,gps and other RFs) jammer.
just put on in a desi way. Especially used to Jam remote controlled bombs.
There are jammers with small antennas which are put inside the car but these ones cover a lot of distance and are most reliable
Check the link
www.3dsecurity.biz/cell-phone-jammer-vehicle.php
you may find many companies making these types of jammers.
A few pics attached for reference.
