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Technology for blocking wireless signals spreads

Industry Standard

March 19, 2001
Web posted at: 12:23 p.m. EST (1723 GMT)

(IDG) -- Picture it now: Movie theaters, concert halls and fancy restaurants, all equipped so cell phones appear to be out of the range of a provider. Or how about corporate boardrooms where mobile phone ringers will no longer disturb the proceedings? The next time your cell phone mysteriously drops out of range, consider the possibility that someone could be silencing your signal.

In today's climate of ever-rising public cell phone use, technology designed to silence mobile phones appears to be gaining acceptance. Cell phone "jamming" equipment -- which sends out radio signals that block nearby cell phones from decoding local cellular networks' signals -- is becoming increasingly available, even though it is currently illegal in the United States. Canada -- whose government opened a 90-day public comment period this week on legalizing cell phone jamming -- has become the latest battleground for this controversial technology.

Industry Canada, the federal body responsible for regulating such devices, is looking for public input on allowing cell phone jamming systems in restaurants, theaters, libraries and other locations where cell phone use is perceived as inappropriate. Canada expects to decide by the end of the year whether to expand the current licensing scheme, which currently allows only law enforcement and government agencies to deploy jamming technology. Government agencies have used jammers to throw a net of silence over hostage and terrorist situations, and to protect privacy in sensitive negotiations. INFOCENTER
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"We're going to gather the widest public views possible on the use of cell phone silencers," said David Warnes, the senior adviser for spectrum policy, to Canada's National Post newspaper. Warnes indicated there is interest in silencing rude mobile phone users in public spaces and requests from businesses that would like to employ the technology to protect privacy in corporate boardrooms.

This is good news for companies like Israel's Netline, which markets a jamming system called the C-Guard Cellular Firewall. The C-Guard comes in two models, a $900 version the size of a videocassette and a higher-powered version for $6,500. Formed by retired Israeli military intelligence officers who were inspired by technology invented by the Israeli army's electronic warfare division, Netline claims to have sold hundreds of jamming systems to U.S. customers, including the Department of Defense and the CIA.

Canada is not alone in its consideration of cell phone jamming technology. Japan has been one of the most visible countries to allow the use of jamming systems. Many systems were sold for private use when they first became available in 1998, but after a rash of installations, the Japanese government instituted a licensing program and put restrictions on the use of cell phone jammers. Now, to obtain a license to operate the equipment, the system must be used only in a government-approved place, like "theaters or concert halls where the degree of public nuisance is significant,'' according to the Ministry of Posts and Communications policy guidelines.

In India, the parliament recently installed jamming devices in its main government buildings to silence the constant disruptions of politicians' cell phones. Reportedly the last straw for India's leaders came when President K.R. Narayanan's address to a joint session of parliament last month was interrupted by ringing cell phones no less than six times.

In the U.S., both the wireless industry and the Federal Communications Commission frown upon the technology. When these jamming systems began receiving media attention in 1999, the FCC issued a public notice reaffirming a 1934 law that prohibits the use of transmitters to block radio communication, warning violators of penalties that could include a year in jail and large fines. The Cellular Telephone Industry Association also points out that this technology is illegal in the U.S., and its position is that it should remain this way.

But if the current cell phone etiquette backlash continues, expect challenges to those laws, just like those from our Canadian neighbors.

Canada to consider licensing cell phone jammers
March 8, 2001
HK to jam cell phones in public places
February 26, 2001
Cell phone suit will get its day in court
January 22, 2001
Study: No overall link between cell phones and brain cancer
December 19, 2000
GM to study driver distraction from in-vehicle gadgets
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