Cell phone jammers raise question: who controls the airwaves?November 9, 2007 by Lisa Zyga in Technology / Consumer & Gadgets
As more people go about chatting obliviously on their cell phones in public places, foreign companies have enjoyed increasing US sales of a new, albeit illegal, device: the cell phone jammer. When you turn it on and slip it in your pocket, the cell phone jammer blocks cell signals within 30 feet.
The jamming technology is not new, but it´s becoming increasingly popular on buses, in restaurants, and in movie theaters. The device works by sending out a powerful radio signal that overwhelms cell phones so that they cannot communicate with cell towers. The gadgets cost around $100 to $1,000 or more, with larger models that can be left on to create a no-call zone.
However, using the jammers is illegal in the US, since the radio frequencies used by cellphone carriers are legally protected by the government, similar to the protected frequencies used by television and radio broadcasters. Cell phone companies spend tens of billions of dollars to lease the frequencies from the government, and expect protection from infringement.
According to a recent article in the New York Times, the Federal Communication Commission (FCC) warns that people caught using cell phone jammers could be fined up to $11,000 for a first offense. FCC investigators have special technology of their own that can detect the jammers. The commission has already prosecuted several US companies for distributing the devices nationally.
While many people find the devices fun as a sort of practical joke, there is also a serious side to the debate. The jammers raise a security threat, since criminals could use them to prevent hostages or others from communicating in an emergency.
But in other situations, private businesses have "no cell phone" policies within limited areas to ensure that their employees´ or clients´ concentration is not interrupted. In these places, people shouldn´t be using cell phones in the first place, and the jammers simply enforce that policy.
The jammers are currently being sold on sites such as UK-based PhoneJammer.com, which reports its sales have increased by 30% from a year ago to around 400 per month. Holiday sales have exceeded 2,000 of the devices.
via: The New York Times
"Cell phone jammers raise question: who controls the airwaves?" November 9, 2007 https://phys.org/news/2007-11-cell-jammers-airwaves.html