You have a European-Asian region TV set if you bought it in Dubai. It probably won't do you any good in North America for use with an antenna since it's likely to have a DVB tuner, not an ATSC tuner. Different and incompatible broadcast standards.
Before wasting more time looking for an adapter for the coax input, you'd do best to look up the specifications of the TV set to see what tuner is installed. If it does not have an ATSC tuner, you'll be limited to HDMI or component inputs, most likely.