High Quality Content by WIKIPEDIA articles! The Active Denial System is a less-lethal, directed-energy weapon developed by the U.S. military. It is a strong millimeter-wave transmitter primarily used for crowd control. Some ADS such as HPEM ADS are also used to disable vehicles. Informally, the weapon is also called pain ray. Raytheon is currently marketing a reduced-range version of this technology. The ADS is currently being considered for deployment in the Iraq War. The ADS works by firing a high-powered beam of electromagnetic radiation in the form of high-frequency microwaves at 95 GHz. In exactly the same way that a microwave oven heats food, the millimeter waves excite the water and fat molecules in the body, instantly heating it and causing intense pain. Such is the nature of dielectric heating that the temperature of a target will continue to rise so long as the beam is applied, at a rate dictated by the target's material and distance, along with the beam's frequency and power level set by the operator.