Functional goals of the research included the following: 1) Detect concealed weapons (firearms, knives, or explosives) on humans at a safe standoff of at least 15 meters. 2) Sensor is portable or can be stationary and covert. 3) Sensor has sufficient resolution to discriminate weapons from cell phones. 4) System is of extremely low-power (safe) active millimeter wave radar to provide higher contrast for weapons detection than the current passive type weapon detection radar. 5) System can be used to detect weapons covertly at airports, train stations, schools with violence, amusement parks, campaign rallies, or were security is concerned with large crowds of people. 6) System can be used as a portable sensor by police officers to detect weapons on suspects at a safe distance.