While travelling Rt 70 through Ohio yesterday I noticed multiple OSP cruisers with a large device mounted to the top, driver side of the lightbar. Looked to be 12 inches high and 12 inches long. Shaped like and inverted L. Some type of specialty antenna or laser device? Hard to describe but saw quite a few yesterday. I am aware of what standard radar antennas look like and these were quite a bit larger than those. Any ideas?