Time signatures above the staff

[Pedro Proença]

Hi 

Is it possible to put time signatures above the staff, on top of the barlines? If so, how would I go about doing it? I've searched the web and came up short

Also, I'd like for, in a score with multiple staves, just one time signature, on the very top of the topmost staff. I'm sure it's doable, I'm just not seeing how.

Thanks in advance