Mobile RTK Setup Checklist: From First Power-On to Fixed

Table of Contents

• What is Mobile RTK?

• 1. Pre-checks

• 2. Powering on the GNSS receiver and connecting

• 3. Correction data reception settings

• 4. Reference station settings check

• 5. Satellite reception status check

• 6. Positioning environment (obstructions and multipath) check

• 7. Acquiring a fixed solution and verifying accuracy

• Simple surveying with LRTK

• FAQ

What is Mobile RTK?

RTK positioning (real-time kinematic positioning) is a technology that uses two GNSS receivers—a base station (reference station) and a rover—to obtain centimeter-level high-precision position information (fixed solution) in real time. Mobile RTK refers to RTK operation on the rover side while moving on site, and its use is expanding across a wide range of fields such as surveying for civil engineering and construction, inspection of structures, and infrastructure management. High-precision positioning, which formerly required specialized surveyors and expensive dedicated equipment, can now be obtained quickly by site personnel themselves using a mobile RTK system.

However, when using mobile RTK for the first time, you may wonder, “What should I do from turning on the power until I get a Fixed solution?” This article explains the steps in checklist format for getting from the first power-on to a Fixed solution. It covers the basic checkpoints so you can avoid troubles caused by misconfiguration and start high-precision positioning smoothly.

1. Pre-checks

Before operating mobile RTK, first check the necessary equipment to bring to the site. Typical mobile RTK positioning requires one RTK-capable GNSS receiver for the rover (if you plan to use your own base station, prepare a base-station receiver as well). Prepare the rover receiver unit and GNSS antenna (or an integrated device with a built-in antenna), communication devices (built-in communication modem or external radio, SIM card, mobile router, etc.), a survey pole or tripod and mounting hardware, a smartphone or tablet (to operate in conjunction with the receiver). Also confirm that batteries are fully charged. Bring spare batteries for the receiver and communication devices or a mobile battery as a precaution for long work sessions. Check that various cables (antenna cable, charging cables, USB connection cables, etc.) are all available beforehand.

Next, planning the work location and environment is also important. Understand the sky visibility and communication environment of the area to be surveyed in advance. Arrange to work where the sky is as open as possible. At sites surrounded by tall buildings or dense forest, positioning conditions may worsen, so select a spot within the site with good visibility if necessary. If installing your own base station, consider in advance the location for the base station (ideally a site with an open sky, stable ground, and preferably near a known reference point coordinate). Also confirm the RTK service or base station operation plan you will use. If you will use a public network RTK service, prepare the connection information and service contract; if you will use your own base station, understand the initial setup procedures for it.

Finally, confirm role assignments within the team. If multiple people will work, decide in advance who will handle the base station and who will operate the rover for measurements. Review procedure documents and equipment manuals and resolve any unclear points in advance. If possible, practice operating the equipment beforehand so you won’t be flustered on the day.

2. Powering on the GNSS receiver and connecting

Once preparations are complete, power on the equipment on site. First, switch on the receiver. Securely mount the rover GNSS receiver’s antenna to the survey pole or tripod, then turn on the power. If using an external antenna type, confirm that the antenna cable is securely connected (it is preferable to have checked for loose connections or cable breakage beforehand). Confirm satellite reception start and power-on status via indicator lamps on the receiver unit.

Next, connect to the smartphone/controller. Launch the dedicated app or software that integrates with the GNSS receiver on your smartphone or tablet and configure the connection to the receiver. Typically, pair the receiver and the device via Bluetooth or Wi‑Fi (some models support USB cable connection). Search for and select the device in the app; when connected correctly, the receiver’s status information should be displayed. At this point, also confirm the receiver’s operating mode. For models that can serve as both base and rover, ensure it is set to rover mode.

Once the receiver is linked to the device, check the GNSS satellite reception status. Even without correction data, many receivers can display the current position via standalone positioning. The app will show the number of satellites captured and the positioning mode (Single, Float, etc.), so confirm that the receiver is acquiring satellite signals. At this stage, without corrections, the display will show a standalone solution (Single) or temporarily a float solution (Float), but you can confirm that the basic operation of the device is normal.

3. Correction data reception settings

Next, configure the correction data reception, which is the core of RTK. Establish communications so the rover can receive correction information from the base station. In many cases, you will use a network RTK correction service (NTRIP method), so configure the connection in the dedicated app. Accurately enter the connection information provided by the service provider (NTRIP server address, port number, mount point name, user ID and password, etc.) and start the connection. Also confirm that your smartphone or the receiver’s built-in communication module is connected to the internet (check that signal strength is adequate and that airplane mode is off). After connecting, confirm that the app displays “Correction: receiving” or an icon indicating communication status (for example, a green antenna icon). If correction data is arriving normally, the rover’s positioning mode should begin to change from Standalone to Float.

If you cannot receive correction data, recheck the communication settings. Carefully verify the server information, ID, and password you entered; a single character error will prevent connection to the server. Also check that mobile data or Wi‑Fi on the smartphone hasn’t been turned off and that signal strength is not extremely weak. Network RTK cannot be used outside mobile network coverage such as underground or deep mountainous areas, so consider using a mobile router on site or preparing your own base station as a countermeasure.

If receiving corrections wirelessly from your own base station, confirm the wireless connection. Ensure that the frequency and channel of the radio attached to the rover receiver match those of the base station, and at this stage confirm that you can receive signals from the base station. Monitor reception via the radio’s receive indicator (blinking or lit) or the radio connection status displayed in the app. If the signal does not reach, check the distance to the base station and whether there are obstructions between them; consider raising the base station antenna height or installing a repeater if necessary.

4. Reference station settings check

If you are using a network RTK service, you do not need to worry about the base station settings, but if you operate your own base station, confirm that the reference station settings are correct. First, set the base station coordinates. It is ideal to set coordinates with as small an error as possible. If a known point exists on site (such as a public survey reference point or a Continuously Operating Reference Station), use that coordinate; if none is available, perform a long observation and average to obtain a high-precision reference coordinate. Even if you set only an approximate coordinate, avoid inputting a value that is drastically different from the actual location. If the base station coordinate is off by tens of meters (tens of ft), it can interfere with the rover’s solution processing and prevent obtaining a Fixed solution (large initial errors prevent the solution from converging). Always recheck the coordinate settings before powering on the base station.

Next, check the baseline length (distance to the base station). If the base and rover are too far apart, accuracy degrades and obtaining a Fixed becomes more difficult even if correction information is received. In general, RTK maintains high accuracy when the baseline length is within a few km to about 10 km. Conversely, at distances well beyond 10 km, atmospheric errors can make solutions unstable and Fixed solutions harder to obtain. When operating your own base station, place the base as close to the work area as possible and keep the baseline short (for wide-area sites, consider relocating the base as needed). If using a public network RTK service (VRS, etc.), a virtual reference station is set near the user to provide corrections, so you do not need to pay particular attention to baseline length.

Finally, check the base station’s transmission status. Verify via the base station’s display or indicator lamps that it is operating correctly and broadcasting correction data (if base-station software allows monitoring of distribution status, check that as well). If the rover receives correction data but does not achieve Fix, suspect possible misconfigurations on the base station (wrong coordinates, incorrect radio frequency, etc.).

5. Satellite reception status check

With correction reception set up, recheck the GNSS satellite reception status. To obtain a stable Fixed solution in RTK, you must capture a sufficient number of satellite signals simultaneously. Generally, at least four satellites are required for three-dimensional positioning, but to obtain a high-precision Fixed solution in RTK, it is desirable to stably receive five to six or more satellites. Check the number of satellites currently captured and the DOP value (dilution of precision) on the app or receiver status screen to confirm whether you meet the required satellite count. If the number of visible satellites is low or the number of usable satellites is extremely small (for example, four or fewer), you will not reach a Fixed solution no matter how long you wait.

Satellite geometry is also important. If satellites are concentrated in only one direction in the sky, the DOP will worsen (positional accuracy decreases) and it becomes difficult to obtain a Fixed solution. The more evenly satellites are distributed across the sky, the better the positioning geometry and the higher the accuracy. If satellite geometry is poor at the current time, consider postponing surveying until a time with better satellite geometry. Use GNSS planner tools in advance to check satellite visibility predictions and schedule work during times with many visible satellites and good geometry to make Fixed acquisition smoother. Also check that the elevation mask (angle threshold to exclude low-elevation satellites) in the receiver or software is not set too high; setting the elevation mask too high excludes all low-elevation satellites and reduces the number of available satellites. A setting around 15° is commonly recommended to balance using low-elevation satellites and reducing noise. In addition, using a multi-GNSS receiver that supports GPS, GLONASS, Galileo, and QZSS (“Michibiki”) is advantageous because more usable satellite systems increase the number of visible satellites. If supported, enable all systems to capture as many satellites as possible.

6. Positioning environment (obstructions and multipath) check

The surrounding environment at the site greatly affects whether RTK achieves a Fix. GNSS signals can be blocked by building facades, terrain, or tree branches, or they can arrive at the receiver via reflected indirect paths. In locations with limited sky visibility, you cannot secure a sufficient number of satellites and obtaining a Fixed solution will be difficult. Nearby tall structures, metal fences, and large machinery or vehicles can cause the receiver to pick up reflected, incorrect signals (multipath), introducing errors into the positioning calculation. To reduce obstructions and multipath—major enemies of high-precision positioning—work in as open a location as possible. Before starting work, survey sky visibility and, if possible, move a few meters (a few ft) to a more open position to perform positioning.

If you must position near buildings or structures, consider some countermeasures. First, adjust the antenna installation position. Extending the pole to raise the antenna as high as possible will reduce being in the building’s shadow and increase satellite visibility. Also consider slightly shifting the point to be measured and observing from a location with a better sky view (this may be difficult if the precise measurement location is required, but seek a compromise where possible). Adjusting the timing of positioning can also be effective. For example, at a site surrounded by buildings, first move to a nearby open area to get a Fix and then move to the target point—this procedure can help maintain Fix compared to remaining at the target point from the start. Once a Fixed solution is obtained, some receivers can maintain Fix for a short time even if the environment slightly degrades.

Multipath mitigation is important as well. If you can attach a ground plane (conductive plate) to the antenna, do so to block reflections from the ground and lower angles. High-end antennas and receivers may include multipath rejection features, but the basic principle is to create an environment that minimizes reflections. Also check for strong radio interference sources (high-voltage power lines, communication antennas, etc.) nearby. Strong electromagnetic noise can adversely affect GNSS reception and prevent Fix acquisition. Reviewing the site’s radio environment and positioning environment is a shortcut to acquiring a Fixed solution.

7. Acquiring a fixed solution and verifying accuracy

If you have completed the necessary checkpoints, the receiver should soon acquire a Fixed solution. If satellite reception is good and correction data is being applied normally, it should not take long for the positioning mode to switch from Float to Fix. Depending on conditions, it is common to obtain a Fixed solution within several tens of seconds to several minutes after powering on the receiver or starting positioning. When the app display changes to “Fix” or a green icon and the position coordinates stabilize, Fixed acquisition is complete. If it takes an excessively long time to reach Fix (for example, more than five minutes without Fix), there is likely some problem. At that point, review the previously mentioned points (satellite count, environment, correction data reception, base station settings, hardware connections, etc.) to check for overlooked issues. Waiting aimlessly in Float will not improve accuracy; identify the cause and take corrective action.

Once you obtain a Fixed solution, verify accuracy. After Fix, maintain that state for a while to confirm the solution is stable (occasionally the positioning engine can misapply and revert to Float quickly). If signals are stable, the Fixed solution should continue. Check PDOP values and estimated error indicators (RMS, etc.) on the positioning software to confirm that values are sufficiently small. Theoretically, an RTK Fixed solution can achieve about 2–3 cm (0.8–1.2 in) horizontal accuracy and a few centimeters to 5 cm (a few in to 2.0 in) in height, but actual errors may be slightly larger depending on the environment. If a known coordinate point (a reference point on site) is nearby, measure it as a test. If the deviation from the known point is within an acceptable range (a few centimeters (a few in)), it demonstrates the system is functioning correctly. If the deviation is large, there may be fundamental issues such as incorrect base station coordinates or equipment malfunction.

After obtaining Fix, proceed with the actual surveying work: measuring points, as-built management, stakeout, etc. Continue to monitor the positioning status during these operations. Satellite reception can change while moving and the solution can revert from Fixed to Float. Monitor the app display or receiver lamps for the current positioning mode; if it falls to Float, do not record measurements forcibly—wait for Fix again before recording. In some cases, temporarily improving the environment (moving slightly, raising the antenna, etc.) can shorten the time to re-Fix. Also pay attention to battery level and communication status during long work sessions and periodically check for problems.

Finally, at the end of the work, be sure to save data and shut down equipment. Confirm that the measured point coordinate data are correctly saved on the device or the cloud and back them up if necessary. Power off the GNSS receiver and any devices used, and recover equipment safely. Completing these closing procedures finishes the mobile RTK positioning work.

Simple surveying with LRTK

So far we have explained the procedures and checkpoints for high-precision positioning using mobile RTK. You can see that considerable preparation and careful checks are required, but if operated correctly, you can obtain stable centimeter-level accuracy on site. On the other hand, some may feel that preparing, configuring, and operating RTK equipment yourself is a high barrier and wonder if RTK surveying can be made easier. The LRTK series answers that need. The LRTK series is a lineup of compact high-performance GNSS receivers provided by Lefixea, designed so that anyone on site can easily use centimeter-level positioning.

LRTK is an innovative solution that combines a smartphone with an ultra-compact GNSS receiver to make RTK surveying—previously large and requiring specialized knowledge—compact and easy to use. Both base and rover fit in the palm of your hand and are easy to carry, and setup on site is quick. Intuitive operation through a dedicated smartphone app guides you through complex coordinate and communication settings. Even inexperienced users can start high-precision positioning in a short time. In addition to receiving network RTK corrections, LRTK supports Japan’s QZSS “Michibiki” CLAS (centimeter-level augmentation service) correction signals, enabling centimeter-level positioning even outside internet coverage in mountainous areas without preparing your own base station.

LRTK receivers, despite their small size and light weight, support multi-GNSS and multi-frequency, enabling stable positioning with a high Fix rate. Usage is simple: connect to a smartphone or tablet and start positioning from the app. For example, the smartphone-integrated model LRTK Phone is an ultra-compact receiver that attaches to an iPhone and weighs only 125 g. It can be carried in a pocket on site and used to perform precision positioning and recording whenever needed. Some models include tilt compensation, allowing automatic correction of the antenna tip position when the pole is tilted. Positioning data can be synchronized to the cloud in real time, allowing immediate sharing of measured coordinates and notes with the team.

Introducing the LRTK series greatly streamlines surveying preparation that used to take half a day, freeing up more time for actual work. Feedback from sites that introduced LRTK reports not only reduced surveying time but also improved construction management accuracy due to consistently stable accuracy. LRTK supports the Ministry of Land, Infrastructure, Transport and Tourism’s i-Construction initiative and is a cutting-edge tool that strongly supports DX (digital transformation) in the construction industry. Even those uneasy about handling RTK equipment can enjoy the benefits of high accuracy while being freed from complicated tasks by adopting LRTK’s simple surveying. For more details on how LRTK can dramatically improve surveying accuracy and productivity, please also visit the [LRTK official site](https://www.lrtk.lefixea.com).

FAQ

Q1: How many satellites are required at minimum to obtain a Fixed solution in RTK? A: Theoretically, four satellites are sufficient for three-dimensional positioning, but to stably obtain a Fixed solution in RTK you generally need five to six or more satellites. In general, the more satellites the better. Choose a receiver that can use not only GPS but also GLONASS, Galileo, and QZSS (Michibiki) to increase the number of satellites you can capture and improve the Fix rate.

Q2: If RTK does not become Fixed easily, how long should I wait? A: Under good conditions, it is common to become Fixed within several tens of seconds to a few minutes after powering on the receiver or starting positioning. If more than five minutes pass without Fix, there is likely a cause. Recheck the points discussed in this article (satellite count, environment, correction data reception, base station settings, etc.). Waiting a long time in Float will not improve accuracy, so identify the cause and take corrective action. Improve the environment or review settings and try positioning again.

Q3: Do weather or time of day affect how easily Fix is obtained? A: Ordinary rain or cloudy weather generally does not severely block GNSS signals, but time-of-day effects can occur. Ionospheric disturbances and satellite geometry can cause reduced positioning accuracy or make Fix more difficult at specific times. For example, daytime hours around 2–5 PM are said to have greater ionospheric effects and degraded accuracy. In urban areas, satellites can be at low elevations at certain times and more easily obscured by tall buildings. If you find obtaining Fix difficult due to environmental factors, try shifting the time and retrying. You may obtain Fix quickly at another time with better satellite geometry.

Q4: Is it acceptable to continue surveying in Float solution? A: Float solutions are less accurate than Fixed. Typically, Float has errors on the order of tens of centimeters to about 1 m, so it is insufficient for precise surveying or construction management. Therefore, avoid hurriedly recording positions while in Float if Fix is not attained quickly. Wait for Fix or try again later with changed conditions. If you cannot get Fix on site, consider switching to static positioning (long observation with post-processing) or take multiple quick measurements and average them to improve accuracy.

Q5: Is it difficult to obtain Fix if the distance from the reference station is far? Any countermeasures? A: Yes, generally the farther you are from the reference station (baseline length), the harder it is to obtain Fix. As you move away, the atmospheric correction effect weakens and solutions tend to become unstable. A countermeasure is to use a public network RTK service (VRS), which is effective. VRS (virtual reference station) services generate a virtual reference near the user and provide correction information, effectively eliminating the distance problem. When using your own base, you can install repeaters to relay radio signals or use higher-power radios to expand coverage. If those options are insufficient, consider temporarily relocating the base station closer to the measurement points or switching to post-processing (PPK) positioning. In any case, keeping the distance to the reference station as short as possible based on site conditions is key to high-precision positioning.