Embraer ERJ-145 (N729)

The posted tail number does not seem to be correct. I am curious about the contraption on top of the plane. Is it a military weapon?

It’s a SAAB GlobalEye - a modified Bombardier Global 6000. The wedge on top is just a giant antenna.

To Be clear then not a Embraer product but a joint venture Bombardier/ Saab aircraft!

The airplane is a military adaption of the commercial Embraer 145. See Embraer R-99