This happened twice yesterday on my 400 mile trip back home coming up on I-57 in IL. As I passed a LEO he flipped on his radar and I got 2 Ka's at once! Seemed rather strange but then around an hour later I was getting a Ka and then another popped up almost the same instance, and there was one LEO on the my side of the road with a victim pulled over. After driving all this time through IL, I've never come across this.
Later, in Indiana, I got the normal Ka's from the ISP and they were single signals.