google PPL ...
http://www.ppluk.com/en/I-Make-Music/Why-Should-I-Become-A-Member/they collect radio broadcast royalties on behalf of the performer and as you are the performer as well as the songwriter you have an entitlement. Check it out..
You should register with PPL as a performer, its in London and linked to PRS, its free, any writing can be registered along with the summary of your musical projects..
Whatever you do its a good place to get information.
Not complicated just read about it on the PPL website.
i may not believe this tomorrow...