As the article suggests, the beam can be reflected back on the oppressors. With some thought and rehearsal, the front line of an action could actually reflect and refocus the beam by forming in the shape of a parabola. Its basic drill team stuff.
January 26, 2007 -- Save your aluminum foil "hats." According to a technology expert who is familiar with the Raytheon Active Denial System (ADS), tested January 24 at Moody Air Force base in Georgia, the millimeter microwave directed beam weapon can be defeated by a crowd of people using aluminum- or gold-coated Mylar to conduct the beam to ground or even direct it back to the Humvee housing the ADS system. Although the Humvee is shielded, any law enforcement or military personnel standing near the Humvee would get a burning taste of their own medicine if the directed beam were reflected back to its source or to a crowd of police. In addition to aluminum or gold coated Mylar, Mylar reflective space blankets, aluminum coated windshield heat protective screens, and more sophisticated and precise corner cube retro-reflectors or Luneburg spheres can all be used to reflect the millimeter wave beam back to its source.
The source we spoke to also revealed that the ADS technology has already been used in Iraq against civilian rioters even though the Pentagon claims it will not be deployable until 2010. The source added that even if the ADS Humvee is present at the anti-war march in Washington tomorrow, Raytheon would not permit its use because of liability issues stemming from potential eye damage and human rights violations. However, WMR has learned that Raytheon is offering the ADS technology to police departments and as a component of home security alarm systems.