Radar gun developed to detect illegal jammers

New Scientist : A UK company, Chronos Technology, has developed a handheld GPS jammer detector and locator. The iPad-sized gadget is aimed at law enforcement agencies and other security operatives who need to pinpoint the source of signals that are causing widespread GPS outages. Consumers have been using the jammers to disrupt local GPS signals in order to avoid paying highway tolls. Jammers can, however, cause widespread problems, such as interfering with airport landing systems, stock exchange transactions, and power-grid operations.