How Accurate Is GPS Time?

By Contributing Writer

GPS, which stands for global positioning system, has become the major instrument used in determining time from one part of the world to the other. It is also extensively used for purposes of transferring time from one time zone to another. The GPS system relies on the global control stations and the Master Control Station (MCS) located at the Falcon Air Force Base near Colorado Springs, Colo., to collect and gather data from all other GPS stations across the world. This article explains, among other things, why GPS timing is regarded as the most reliant timing system in the world.

History of GPS

Since navigation and exploration began, many explorers have sought a process that would enable them to locate their exact location in the world at all times. Such a problem lasted until in 1993 when the U.S. Air Force rocketed its new satellite, the GPS system, into space. This is the last of the 24 satellites needed to complete its task of time configuration from satellites. This last satellite was equipped with a GPS receiver, a product that can be bought for only a few hundred dollars. The era of GPS timing has been born.

How Accurate is the GPS Timing?

The GPS timing is undoubtedly the most accurate time measurement in the world. Anyone with a GPS receiver can now locate his global position, including longitude, latitude and altitude. More importantly the GPS timing clock is accurate up to a billionth of a second; no other time-monitoring equipment beats the accuracy level of GPS timing.

How does the GPS System work?

As indicated earlier, the Master Control Station located near Colorado Springs collects the data from the five GPS monitor stations in different locations of the world. GPS satellites relay their signals to ground equipments capable of receiving the GPS signals. These receivers must always be exposed to the sky without anything obstructing their views. These receivers are used only outside where their signal-receiving capabilities are exposed to the sky, but the location of other GPS instruments receiving digital data such as cell phones does not matter. The accuracy of GPS timing depends on the atomic clocks onboard the satellites, with their precise timing referenced by the atomic clocks at the U.S. Naval Observatory.

Managing Errors Within GPS Timing

The time provided by the GPS signal also include UTC corrections. Both components are included in the signal, which is being broadcast in real time. It should also be noted that the broadcast signal also includes the difference between the UTC signal and the GPS signal, often calculated using the following equation (GPS time - UTC time = 11 seconds). The rate and time difference is also included within the real time broadcast signal. The result is that all the GPS receivers are able to calculate the accurate time depending on the time zone where such receiver is located.

Benefits of GPS

Today the GPS technology has wide applications. Many kinds of GPS receivers are coming to the market. Some are integrated inside cars. Many new phones coming to the market have GPS capabilities; some new watches receive GPS data. GPS technology is helping in many ways to save human lives as well, for example, by pinpointing their locations in ships at sea. Many new jobs and employment opportunities have risen through the evolution of the GPS technology. The industry has generated nearly 100,000 new jobs and is growing.

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