Anti-GPS jamming technology to come within 3 years

Technology to prevent jamming of the global positioning system, or GPS, is expected to be developed for the private sector within three years after being the exclusive domain of national defense.

Electronics and Telecommunications Research Institute will start developing from April 1 a technology that can detect and respond to the disruption of GPS signals.

Lee Sang-uk, head of the institute’s satellite legalization research team, said, “We began preparing for this right after North Korea disrupted GPS signals in August last year, and we’ll continue studying this over the next three years.”

The think tank will first develop a technique to detect disruptions and their sources and a device to shield major facilities against disruptions. Over the mid to long term, it will develop and distribute devices that can separate original GPS signals from disruptive ones. The disruption of GPS signals can wreak havoc not just on the military but on civilian facilities.

○ Low-powered disruption devices easy to make

Signals of the GPS system is only 1/30th that of mobile reception. Since the signal is weak, it is vulnerable to interference.

“As GPS signals are extremely weak, you can impact GPS devices without using complicated codes,” said Lee Sang-jeong, an electrical engineering professor at Chungnam National University. “It’s easy to make a disruption device when you get a signal generator.”

Experts say a low-powered device as weak as one watt can cause GPS signals to malfunction. Professor Lee said, “Given that incandescent bulbs at home are 30 watts, you can make a portable disruption device with a tiny amount of power.”

Locating North Korea’s devices was possible because they used high-powered equipment but low-powered devices are harder to detect.

○ Bigger inconvenience for civilians

“Mobile base stations, financial transactions and smart grids rely on GPS signals for synchronization,” Lee Sang-uk said. “If there is any disruption, it might cause a problem.”

Mobile networks use GPS information to synchronize the clocks of mobile stations. Mobile users can use their phones seamlessly on the move only when such clocks are consistent.

Though the 3G mobile network can run for 24 hours with independent clocks at mobile stations despite disruptions, interrupted communications can occur if the disruptions last for a long time.

kyoutae@donga.com