I use to wake up every Saturday to watch this show. The story is futuristic. The earth is being attacked by alans . When a Kid who has some sort of BIO suit shows up( Of course the kid can't remember his past). Anyway as the series goes on He finds out that these aliens that are attacking earth are controlled by his race. Everyone in his race can summon this bio suit like thing. The series has alt of space battles and ground battles. One thing that does stick out in my mind is that every time the main character went off into battle with his human counter parts is that they took off in a ship that used a "space ramp". Well sorry for the lack of info but if anyone can tell me the name of that series it would be awesome.

Not a lot of info to go on, but I'll give it a try.
One series does spring to mind. A show that came on from 1995-1996, it was call Teknoman. It aired on UPN Kids. It is about an alien, amnesiac. A mysterious young man who had the ability to transform into the powerful warrior known as Tekkaman Blade. Call Teknoman in American, the original series was called Tekkaman Blade in Japan.
Here is a link to a very clear clip of the American Teknoman opening scene on YouTube.

YouTube - teknoman opening good quality

Let me know if this is what you are looking for.