Solution For Loud Cats

So we have a dilemma at our house. Apparently some cats have decided our backyard is their new 'meeting place.'

They get together and do their thing. lol If you have never heard cat's, they are loud and when they are right outside your bedroom window, you can guarantee there will be many sleepless nights! The cat's have been keeping us up more than our 9 month old. I'm telling you, it's 2-3 times a week. I've got a 'playa cat' on my hand's. Help! I need suggestion's for a solution?