When GPS isn't available, it's not just impossible to navigate." We rely on GPS without realizing it," says Donald Jewelry, editor of GPS World magazine, who built GPS systems for the U.S. Air Force. According to him, there are more than 1 billion GPS receivers in operation, but more than 90 percent of them are only used to receive accurate time data from satellites. Mobile phones are a prime example of this usage. In one radio tower, as the user moves, it is handed over to another radio tower and must therefore be synchronized with each other.GPS time signals are a cheap and reliable method.
The timing of each radio tower is also used to identify each other. In fact, many wireless communication devices use GPS time adjustments to synchronize. Perhaps this is what caused the unrest in San Diego in 2007.GPS time adjustments are also used as time stamps for financial transactions such as stocks.ATM can also communicate wirelessly. This is because it uses time-based encryption code that requires synchronization. The reason the ATMs were shut down during the San Diego incident is still unknown but could be related. Power companies also use GPS time to manage their grids.
If the frequency periods of multiple power sources do not match, these sources will partially cancel each other out, reducing efficiency. With accurate time signals, you can know exactly when each cycle begins. For example, the U.S. power grid needs to synchronize more than 5,000 power sources. However, in 2006, the GPS was temporarily disabled due to sunspot activity, which made it impossible to know the destination of power supply and a billing error. This means a power outage could be caused by a GPS error. Given the potential for these problems, the law is taking action against GPS jammers.
The Federal Communications Commission (FCC) announced it would fine sellers and owners of jamming devices. The problem for the authorities, however, is that most of the sellers are in East Asia and the law covers only the use of jammers, often without them at all. An incident last year at New Ark International Airport in New Jersey found that just one jammer can cause chaos. Airport controllers had just installed a new GPS-based landing system to allow planes to enter areas with poor visibility. However, the system shuts down once or twice a day, and it can take months to figure out why.
The reasons are portable GPS jammers and drivers who once cheated highway tolls near the New Jersey Turnpike. Drivers pass through this place twice a day, each time coming down from the airport system. Without GPS, future airport control systems won't work, but so will railways. Fra is trying to make GPS the centerpiece of its rail management plan.GPS becomes increasingly important when police and fire departments arrive on the scene.
