How does rtk work

Even a few years back, the Global Navigation Satellite System could determine the position with an accuracy of meters.

While the difference between a few meters and a few centimeters can still be measured by a measuring tape, the difference that it makes for technological advancements in our time is astronomical. As automation has been adopted by the public as a means for making life easier and technology more manageable, users have also become substantially more dependent on it.

GNSS receivers had to measure the time taken for a signal to reach the receiver from the satellite by traveling through the ionosphere and atmosphere. These initial barriers slowed the signal. Which is why GNSS had low accuracy. It has only been a few years since RTK was introduced to the public but in Bluetooth signal. Its extortionate price made it impossible for the engineering and environmental firms, as well the government land management group to afford them.

With the arrival of Bluetooth RTK, its price dropped significantly which eventually made it affordable for the rest of the industries. One remains static while the other moves around freely. These two receivers are called the base station and rover respectively. The job of the former is to stay fixed and send corrected data to the latter. The rover than calculates the distance using the data and produces a centimeter-accurate position.

Understanding the working process of RTK can be intimidating. RTK GPS is dependent on different transmissions and corrections methods that can be used for determining locations.

The corrections to improve the location accuracy are either received from a dedicated base station or from the RTK base station. The most efficient and most cost-effective way to utilize an RTK receiver is through real-time corrections provided by a base station. These base stations typically are purchased with the RTK receiver but there are other private and governmental organizations that provide pay-for-service access to permanent base stations throughout cities or localities.

For example, travel time on a cloudy day and in clear sky conditions would be different. That is why it is difficult for a standalone receiver to precisely determine its position. RTK is a technology that solves this issue. Two receivers are used in RTK. One of them is stationary, another moves freely. They are called base station and rover. The base's mission is to stay in one place and send corrections to a moving receiver. Network RTK is based on the use of several widely spaced permanent stations.

Depending on the implementation, positioning data from the permanent stations is regularly communicated to a central processing station. On demand from RTK user terminals, which transmit their approximate location to the central station, the central station calculates and transmits correction information or corrected position to the RTK user terminal. The benefit of this approach is an overall reduction in the number of RTK base stations required.

Depending on the implementation, data may be transmitted over cellular radio links or other wireless medium. Chapter 5 - Resolving Errors.