Network RTK vs Single-Base RTK Explained
Understand VRS, MAC, FKP, and when to choose a network solution over a local base station.
Single-base RTK uses corrections from one reference station. Network RTK combines data from many stations to model errors across an entire region. Both can deliver centimetre accuracy, but they behave very differently as you move around.
Single-base RTK
The rover uses one base. Errors grow by roughly 1 mm for every kilometre of distance (often written as 1 ppm), and beyond about 20 to 40 km it becomes hard to get a reliable fix. It is simple, works with almost any receiver and is ideal when you can set up your own base close to the job.
Network RTK
A network processes data from stations typically 50 to 70 km apart and models how atmospheric and orbit errors vary between them. The rover gets corrections that are tailored to its own location, so accuracy stays consistent across the whole coverage area.
The common network methods
- VRS (Virtual Reference Station): the rover sends its rough position and the network creates a virtual base right next to it. Widely supported and easy to use.
- MAC (Master-Auxiliary Concept): the network sends data from a master station plus differences to nearby auxiliary stations, letting the rover do part of the modelling. Standardised in RTCM 3.
- FKP (area correction parameters): the network broadcasts gradients that describe how errors change across an area. Works one way, with no need to send the rover's position.
- Nearest base: the network simply picks the closest real station, which behaves like single-base RTK.
Which should you choose?
If you work across a wide area and have mobile data, network RTK (usually VRS) is the most convenient choice. If you work in one place, in remote areas without coverage, or need full control over your reference point, a local base with a radio link is often better.