Hawking Technologies HWREN1 Signal Weak

I have a Roku box (wireless internet connector for my HDTV) in my TV room. The room was added and has an outside wall between the room and my house. The Hawking HWREN1 cannot pick up the signal for my router within this room. I have to put it near the room but on the other side of the wall. Unfortunately, the wall degrades the signal to the Roku box. As a result the streaming videos run at low resolution.

Are there any suggestions to help kick up the HDTV's resolution?

I'm a new member but am experienced with wireless networks and boosters.