The new version, called Silent Guardian, has a range of about 250 meters. The radar dish like device projects a "burn ray" that is about four feet in diameter. It is effective in fog, smoke and rain. The manufacturer is pitching the Silent Guardian to the navy (for ship protection), the State Department (for embassy protection) and organizations like the border patrol, or anyone looking for a non-lethal way to quickly disperse crowds.
Deployment of ADS has been delayed for years because of concerns about how non-lethal it really is. ADS has been fired, in tests, over 2,500 times. Many of these firings were against human volunteers, and the device performed as predicted, without any permanent damage. But generations of exposure to lurid science fiction descriptions of "death rays" has made the defense bureaucrats anxious over the negative public relations potential if something like ADS was actually used. From a publicity perspective, using more lethal "non-lethal-weapons" is preferable to deploying something safer, but that could be described, however incorrectly, as a "death ray."
The manufacturer (Raytheon) of the microwave Active Denial System (ADS), has developed a smaller version ( Silent Guardian) for civilian markets. The microwave ADS looks like a radar dish. When pointed at people and turned on, it creates a burning sensation on the skin of its victims, causing them to want to leave the area, or at least greatly distracts them. The microwave weapon has a range of about 500 meters. ADS is carried on a hummer or Stryker, along with a machine-gun and other non-lethal weapons. The proposed ROE (Rules of Engagement) for ADS are that anyone who keeps coming after getting hit with microwave is assumed to have evil intent, and will be killed. The microwave is believed to be particularly useful for terrorists who hide in crowds of women and children, using the human shields to get close enough to make an attack. This has been encountered in Somalia and Iraq.