Sensor grenades. You can take up to two, and I hear that they give enemies the VSAT indicator instead of the red dot. But I haven't seen it yet.
Use the eyeballs perk.
If you just admitted you camp then why worrie about K/D? Serious question because I like to have at least a 2 K/D also but not if im sitting in a corner....The motion sensor was cool though but couldnt count on it much because of ghost type perks running around everywhere.