A US company made the prototype of such a weapon for the marine corps in 2004. The weapon, codenamed Medusa, was intended to cause a “temporarily incapacitating effect” but “with a low probability of fatality or permanent injury”. These weapons used microwave frequencies, able to disrupt brain function without any burning sensation. Many people have suffered from symptoms, including dizziness, loss of balance, nausea and headaches. The impact on some of the victims has been debilitating and long-lasting. Also known as “directed pulsed radio frequency energy”. That auditory research eventually led to the Long Range Acoustic Device, or “sound cannon”, used by some police forces against demonstrators last summer. These effects are described in the “significant research” conducted into the effects of pulsed, rather than continuous wave RF exposure. “Military personnel exposed to non-thermal microwave radiation were said to have experienced headache, fatigue, dizziness, irritability, sleeplessness, depression, anxiety, forgetfulness, and lack of concentration, as well as internal sound perception,” says the report.