How to set up an RTK base station: step-by-step for base and rover

What is an RTK base station and how does base and rover work?

An RTK base station is a GNSS receiver set up on a fixed point that continuously compares the satellite signals it receives with its known position and broadcasts correction data. A second receiver, the rover, uses those corrections to calculate its own position to centimetre level in real time. RTK stands for real-time kinematic.

Because base and rover see almost the same satellite orbit, clock and atmospheric errors, the corrections cancel most of them. The remaining error grows slowly with distance from the base, which is why RTK accuracy is often quoted as a fixed value plus parts per million (ppm) of the baseline. Our introduction to RTK GPS explains the principle in more detail.

Corrections are usually sent in the RTCM 3.x format, either by UHF radio or over the internet. A single base can serve several rovers at once.

What equipment does a GPS base and rover setup need?

A complete GNSS base and rover kit is two receivers, a way of sending corrections between them, and the accessories to set them up accurately.

Our E1 GNSS RTK receiver works as radio base, radio rover or network rover, with an internal UHF radio of typically 5 km range in open terrain and up to 20 h battery life, so two identical units form a full base and rover kit.

How to set up an RTK base station step by step

The procedure below applies to most RTK GPS base station setups. Field software menus differ, but the decisions are the same.

1. Choose the site. Pick a stable point with open sky above about 10–15° elevation, away from buildings, trees, power lines and metal surfaces that cause multipath. For radio work, higher ground improves range.
2. Set up the tripod. Centre and level a tribrach over the point on a firm tripod such as our aluminium survey tripod, then attach the receiver with an adapter.
3. Measure the antenna height. Measure to the receiver's reference mark (vertical or slant) and record the method. Measure twice and note it in the field book.
4. Connect the controller to the base by Bluetooth and create or open the job with the correct coordinate system and geoid model.
5. Set the base position. Enter published coordinates of a known control point, or use an averaged autonomous position for a new local setup (see the next section).
6. Configure the data link. Select radio channel and frequency, protocol, air baud rate and transmit power, or internet caster details for NTRIP.
7. Start the base and confirm on the controller that it is transmitting corrections.

Known point or unknown point: setting base coordinates

The base coordinates define the position of every rover point, so an error at the base shifts the whole survey by the same amount. You have two options.

• Base on a known point – enter the published or previously surveyed coordinates of a control mark. Rover results are then directly in the project system. This is the preferred method.
• Base on an unknown point – the receiver averages its autonomous position, which is typically only accurate to a few metres. The survey is internally consistent but offset. Fix it afterwards by measuring known points and applying a site calibration (localisation), or by post-processing the base position against CORS data.

If you return to the same site on another day, set the base on the same mark and use the same coordinates. Mixing different base positions on one project is a common cause of unexplained offsets.

Configuring the rover and checking a fixed solution

The rover must use the same correction format and data link settings as the base. Once it receives corrections it moves from autonomous to float and then to a fixed solution.

1. Set the rover to radio rover (or network rover) mode with the same channel, protocol and air baud rate as the base.
2. Enter the pole height and check the pole bubble or IMU tilt calibration.
3. Wait for a fixed solution; do not record survey points on float.
4. Measure a known check point and compare coordinates and height with the published values.
5. Re-check a known point at the end of the session, and after any base disturbance.

Initialisation is typically a few seconds in open sky with modern receivers. If the rover will not fix, check sky view, radio reception, matching settings and correct base coordinates.

How far can the rover be from the base? Radio range and RTK radio antenna

RTK radio range depends mostly on antenna height, terrain and transmit power, not just on the radio specification. UHF signals travel by line of sight, so hills, buildings and dense vegetation shorten range considerably.

An internal receiver radio typically covers a few kilometres. To extend range, use an external base radio with a mast-mounted RTK radio antenna raised several metres above the ground. Our external UHF radio operates at 410–470 MHz with 5 W or 25 W transmit power, an N-type antenna connector and IP67 sealing.

Two further limits apply:

• Baseline length – accuracy degrades with distance; many surveyors keep baselines within about 10 km for routine centimetre work.
• Licensing – UHF frequencies and transmit power are regulated in most countries. Check local rules and licence requirements before transmitting at high power.

Common RTK base station mistakes and how to avoid them

Most RTK problems trace back to a handful of setup mistakes. Each one produces results that look precise but are wrong, which is why checks on known points matter.

Own base station or network RTK?

Your own base suits remote sites, areas without CORS coverage or mobile data, and jobs that need a fixed local reference. Network RTK suits areas with good coverage and saves carrying and guarding a base.

Network RTK delivers corrections from a CORS network over the internet using NTRIP, explained in our NTRIP and CORS guide. Many firms use both: network RTK where available and their own base elsewhere. To equip a crew with a base and rover kit and external radio, request a quote.

Frequently asked questions