Hot Plasma Shield
Plasma shields can put a series of small plasma explosions in the path of an incoming rocket-propelled grenade (RPG), bullet or other projectile. These are only very small explosions, but since they can be precisely placed on the nose of the missile, this is not a problem. A Plasma Shield producing a hundred detonations a second could put thirty of them in the path of an incoming RPG round if it’s going at 300 meter per second.
Cold Plasma Shield
A plasma's charged particles interact constantly, creating localized attractions or repulsions. An external energy attack, from weapons such as lasers, high powered microwave bursts, or particle beams, would be caught up in the plasma's complex electromagnetic fields and dissapated or deflected. If the plasma could be made sufficiently dense, it could even deflect missiles and other projectiles. The process of absorbing and dissapating energy could also go a long way into defeating radar, IR detectors would be the primary sensor used in space, so this sort of "cloaking" ability would be of limited use.