Clueless about this PCB

[Belochka]

I need some help concerning a PCB. It's the receiving part of a set of wireless HDMI transmitters. The problem is the range is insufficient. I'm thinking of enhancing/adding the built-in antenna, but I can't manage to find it. Besides this major problem, theres also a small black cube sticking out. I'm kinda wondering what it might be for.
Any help would be appreciated.

Thanks in advance!

 

[Belochka]

Seems like I messed up the image code, can't edit the OP sadly enough. The link is correct though.

 

[Belochka]

Sigh.. Can't even edit the above post. If a moderator sees this, please delete this post and the one above and copy the link in this post into the OP. Ty.