Forget boosters, you would be better off trying to stick an indoor antenna in your dorm room window. Boosters are great if you install them before the distribution system, so that an already good signal will still be good after its been split 100 ways.
But once a signal is already degraded, there isnt much you can do about it. If other rooms nearby have better picture than you, it could be the downcable to your room or the socket is faulty, and that wont be fixed with a booster either, but building services can help that.