10 Tips for Improving RTK Accuracy

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Optimize satellite geometry (how to keep GDOP low)
One of the most influential factors in RTK accuracy is the spatial arrangement (geometry) of the satellites being used. If the satellites are clustered in one sector of the sky, the geometry is weak and the GDOP (Geometric Dilution of Precision) value becomes large. A high GDOP increases positioning error and makes it harder to obtain and maintain a stable fixed solution. Conversely, when the satellites are evenly distributed across the entire sky, the geometry is strong and GDOP remains low.

Therefore, when selecting the time of day and location for a survey, it is advisable to check the satellite configuration in advance—using a GNSS planner, for example—and schedule work during periods when DOP values are low. Modern receivers support not only GPS but also multi-GNSS constellations such as GLONASS, Galileo, and QZSS (“Michibiki”); increasing the number of satellites in use generally lowers DOP and improves accuracy. Another key point is not to set the receiver’s elevation-mask angle (the cutoff that excludes low-elevation satellites) too high. By using satellites down to about 15 ° elevation in a balanced manner, you can maintain good horizontal position accuracy (HDOP).

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Differences in geometry caused by satellite placement: In the left illustration (a), satellites S1 and S2 are arranged orthogonally, providing higher positioning accuracy (low DOP). In the right illustration (b), the satellites are close together, so the uncertainty area (gray region) is larger, resulting in a high DOP.
Optimizing satellite geometry and keeping DOP values low is the first step toward achieving high-precision positioning.

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Thorough Multipath Countermeasures (Avoiding the Influence of High-Rise Buildings and Other Obstacles)
In urban canyons or mountainous terrain, GNSS signals are often reflected off building walls, rock faces, and similar surfaces, creating multipath. Because the reflected signal reaches the receiver slightly later than the direct signal, the measured range is lengthened, introducing errors into the position calculation.

Multipath is a major adversary of RTK positioning, so rigorous countermeasures are essential. First, choose survey sites that are as open as possible, avoiding potential reflectors such as tall buildings, metal structures, and large vehicles. If you must work near buildings, install the receiver antenna as high as feasible to reduce the impact of reflected waves. Where possible, attach a ground plane (metal plate) beneath the antenna to block reflections coming from below.

Some high-performance GNSS antennas and receivers include built-in multipath rejection, but the basic principle is to “create an environment that minimizes reflections.” It is also effective to set the elevation-mask angle appropriately (e.g., 15°–20°) to exclude low-elevation satellites whose signals are more likely to reflect off the ground or buildings. By thoroughly addressing multipath, you can obtain a more stable fixed solution.

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Example of a multipath environment in urban areas: In city centers crowded with high-rise buildings—so-called “urban canyons”—satellite signals are easily blocked or reflected (multipath). Ideally, choose positioning sites as far from buildings as possible, where you have a wide, unobstructed view of the sky.

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Set an Appropriate Distance (Baseline Length) Between the Base Station and the Rover

Because RTK achieves high accuracy through relative positioning between a base station (fixed) and a rover (moving), accuracy degrades if the distance—or baseline length—between them becomes too great. The satellite-signal errors received at the two sites (ionospheric delay, satellite-clock errors, etc.) vary with distance, making the corrections less effective. In general, keeping the baseline within 10 km is desirable; beyond that, a fixed solution may take longer to obtain, and positioning errors can grow to several centimeters or more.

If you can deploy your own base station, place it as close to the work area as possible. If that is impractical, you can use nearby electronic reference stations or a VRS (Virtual Reference Station) service provided by local authorities or private companies. A network-RTK setup that uses VRS (via an Ntrip service) generates a virtual base station near the user, effectively shrinking the baseline to only a few kilometers. A shorter baseline reduces ionospheric and tropospheric error differences, enabling faster and more stable fixed solutions.

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Verify NTRIP Correction Quality (Select the Proper Corrections)

When you use network-based RTK, the accuracy of your positioning depends directly on the quality of the reference-station data (corrections) you receive via NTRIP. First, make sure the type of correction stream matches your rover receiver. A single-frequency rover should use a single-frequency correction (e.g., MSM4); a multi-frequency rover should use a higher-precision stream such as MSM7. Always pick a data format and satellite constellation correction that your hardware supports.

If several base-station networks or services are available, choose a correction source located as close as possible to the rover—or one with a solid performance record—for greater stability. The NTRIP communication link itself is also critical. When connecting through a cellular network or pocket Wi-Fi, work in an area with strong signal strength to avoid latency or dropouts. Large timing lags in correction data can make the fixed solution unstable or cause it to fall back to float.

Monitor the RTK status on your receiver or app—check indicators such as “Age of Differential” and the flow of RTCM messages—to ensure corrections are arriving in real time. If necessary, switch to a different NTRIP mount point or change the communication link so that you always have a reliable, high-quality correction stream.

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Avoid Radio-Frequency Interference in the Positioning Environment (High-Voltage Lines and Wi-Fi Interference)
Because RTK relies on receiving very weak satellite signals, you must watch out for interference from strong nearby transmissions. For instance, a strong electromagnetic field generated near high-voltage power lines can disturb GNSS reception. Likewise, if construction radios, Wi-Fi routers, or cellular base stations are operating close to your survey site, their signals can leak into the receiver and become a source of noise.
The best countermeasure is to conduct positioning as far as possible from such strong RF sources. Stay clear of areas directly beneath high-tension lines or near TV and radio broadcast antennas. If you absolutely must work nearby, consider using any noise-filter accessories provided with your receiver. You can also reduce interference through rover settings—turn off unused wireless functions (e.g., built-in radios or Bluetooth) and keep other devices at a distance.
Japan’s RTK environment also makes use of L6-band signals from the QZSS constellation (“Michibiki”), so minimizing interference in that band is equally beneficial. In short, choosing an RF-clean environment is the quickest route to achieving and maintaining a fixed RTK solution.

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Optimizing Receiver Installation (Level Mounting & Antenna-Height Adjustment)

Did you know that the way you set up an RTK receiver and its antenna can change the accuracy you achieve? First, mount the antenna as level as possible so it has no tilt. A tilted antenna skews its gain pattern toward the satellites and can—even in the worst case—introduce bias errors into the position solution. If you use a tripod or pole, level the antenna with a bubble level.

Antenna height is just as important. Placing the antenna right at ground level makes it more susceptible to ground reflections (multipath) and to blockage by nearby objects. Mounting the antenna on a pole about 1.5 to 2 meters high reduces these effects and improves sky visibility. However, if the antenna sways at the top of the pole it will affect positioning, so be sure to secure it firmly. In strong winds, avoid using an overly long pole; mount the antenna lower and adapt to conditions.

If you install your own base station, first calibrate it on a known control point so its height and coordinates are correct—the base-station position error passes directly into the rover’s absolute accuracy. Also measure and record the antenna height accurately whenever you set up. By following these basic installation practices, you can eliminate unnecessary error sources and maintain RTK accuracy.

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Measurement Procedure for Stabilizing an RTK Fix Solution (Differences Between Static and Kinematic Positioning)
To obtain a reliable fixed-integer (Fix) solution in the field, proper measurement procedure and a few operational tricks are essential. Immediately after starting the receiver, remain still for several dozen seconds until satellite acquisition and the reception of correction data have stabilized and the first Fix solution is achieved. If you begin moving as soon as positioning starts, the solution will still be in Float mode, meaning the position is not yet fixed and any data you log may be of lower accuracy.

For static positioning, stay at a single point long enough—sometimes tens of seconds or more—to maintain the Fix solution and average the position readings during that period, thereby improving accuracy. For kinematic (moving) surveys, positions are recorded continuously while you move; however, if the Fix solution drops to Float even once, the data collected during that interval will not be highly accurate. Even during kinematic work, make it a habit to pause at key locations, wait for the solution to return to Fix, and then record the point.

Preparatory steps also matter: warm up the receiver before measuring, check satellite signal quality, and, if necessary, fine-tune the antenna position. If the Fix solution becomes unstable during the survey, you can deliberately reset the session—by reacquiring corrections or rebooting the receiver—to regain a stable Fix quickly. By ensuring that you log data only when a solid Fix solution is present, you can maximize RTK’s full precision potential.

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Optimizing LRTK App Settings (How to Use the Dedicated LRTK App)
If you use a high-precision GNSS receiver from the LRTK series, fine-tuning the dedicated LRTK app can further improve both accuracy and ease of operation. The LRTK app links your smartphone to the LRTK receiver and is designed for intuitive configuration of NTRIP corrections, switching positioning modes, and recording data.First, confirm the coordinate reference system you will use within the app. When Japanese public coordinates are required, set the datum to JGD2011 or JGD2022 and, if necessary, enable geoid-to-ellipsoid height conversion (the app can automatically correct elevations via the Geospatial Information Authority of Japan’s correction API).Next, in the NTRIP connection settings, enter the correct correction-server address, port, mount point, and login details, and make sure the correction data type (e.g., MSM4 or MSM7) matches your LRTK receiver.If you are operating in base-station mode, you can launch the LRTK unit in the app as a “Fixed Station” and configure nearby rovers to receive its data.The LRTK app also offers averaged positioning and continuous positioning (logging). For static points, averaged positioning lets you obtain a stable coordinate by averaging over a specified time or number of epochs, reducing single-epoch scatter. During mobile surveys, the app can log up to 10 points per second, capturing high-precision trajectories while you move.

The app also offers features such as embedding location data in photos and tilt compensation (when used with compatible devices), so adjust the settings to suit on-site conditions. If you are unsure about the settings menu, refer to the manufacturer’s manual or Q&A site, and create an optimal settings profile for your LRTK device in advance to ensure smooth operation in the field.

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How to Check the Accuracy of Measurement Results (Monitoring HDOP and Fix/Float Status)
In RTK field operations, it is crucial to judge the quality of your positioning results on the spot; discovering errors only after returning to the office is too late. Always verify in real time whether the data you are collecting can be trusted. The first step is to confirm the solution type shown on your receiver or in the app. A display of “FIX” (fixed solution) is the prerequisite for high accuracy, whereas “FLOAT,” “DGNSS,” or “SINGLE” indicates lower precision. Keep a constant eye on whether you are in a fixed state, and if the solution drops to Float, promptly eliminate the cause—such as by moving away from obstructions or reacquiring base-station data.Next, monitor the DOP values, especially the HDOP (Horizontal Dilution of Precision). As a rule of thumb, an HDOP of 2.0 or below signifies high precision, values between 2 and 5 are generally acceptable, and anything above 5 raises concerns about degraded accuracy. By continuously checking both the solution type and the HDOP in real time, you can ensure that your RTK data remain reliable throughout the survey.

If the HDOP or PDOP climbs sharply during positioning, it is wise to pause the survey and wait until the satellite geometry improves. As an additional accuracy check, verify against a known control point. If your site has a point whose coordinates are already established—such as a benchmark or stake—measure it and see how much error appears. An error confined to a few centimeters indicates the system is functioning correctly. It is also helpful to observe each measured point several times and compare the resulting coordinates; if two readings of the same point differ by more than about 5 cm, an underlying issue may exist. Finally, when logging data, save metadata such as time, positioning mode, and satellite count so you can diagnose problems later if they arise.

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10. Troubleshooting: What to Do When a Fix Cannot Be Achieved

Even with thorough preparation, you may sometimes find that you cannot obtain—or cannot maintain—a fixed-integer solution in the field. When this happens, remain calm and work through the following checks and remedies.First, inspect satellite reception. If the number of visible satellites is unusually low or certain signals are weak, look around to see whether anything is blocking the antenna’s view of the sky. In many cases, simply moving the antenna a few meters can bring additional satellites into view and improve the situation.Next, confirm that you are receiving correction data. Check the app display or the NTRIP client log to see whether the NTRIP connection has dropped or the base station has stopped transmitting. Without corrections, a fixed solution is impossible, so try rebooting your mobile router or relocating to an area with stronger cellular coverage.Even when corrections are flowing, mismatched settings—such as an incorrect base-station position or an inconsistent coordinate system—can still prevent a fix. If you are operating your own base station, double-check its coordinates and, if in doubt, compare them with official control-point coordinates.

Another effective remedy is to reset the receiver and software settings. Switch the positioning mode back to Single, then return to RTK, reboot the receiver, or try a different correction channel—for example, switch to a satellite-based service such as CLAS if your internet link is unstable.If the environment looks fine, suspect hardware issues: a broken antenna cable or a loose connector can stop you from getting a Fix. Reseat any plugs, and clean dirty contacts if necessary.When all else fails, consider a change of venue. Moving to an area with a clearer view of the sky can sometimes yield a Fix almost immediately.The key is to diagnose quickly instead of remaining stuck in the field while insisting on a Fix. By methodically isolating possible causes—and keeping plenty of troubleshooting options in reserve—you will be able to respond calmly and efficiently whenever problems arise.

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Applications and Adoption Benefits of LRTK

Finally, let’s look at how LRTK devices—compact, lightweight units that deliver high-precision RTK positioning with minimal effort—can be applied in the field and what advantages they offer. The LRTK series from Lefixea Corporation is a state-of-the-art RTK-GNSS solution engineered for ease of use by on-site professionals. In a single phrase, its appeal lies in the perfect trio of being small and light, easy to operate, and highly accurate.

• Compact and lightweight: Conventional survey-grade GNSS equipment becomes bulky once you add batteries and antennas, but an LRTK device is pocket-sized and weighs only a few hundred grams. Take the smartphone-integrated “LRTK Phone,” for instance: it weighs about 125 g and is just 13 mm thick, turning an iPhone into an all-purpose surveying instrument you can carry with ease. Because it is so small and light, you can keep it on you throughout the workday without fatigue—truly a “one-device-per-person” tool that is ready whenever you need it.

• Easy operation: LRTK devices can be controlled intuitively through the dedicated LRTK app. Simply pair the unit with a smartphone over Bluetooth or Wi-Fi, and follow the on-screen prompts to complete even complex GNSS settings. In the field, you just power on the device and use the phone to begin positioning instantly—while also managing tasks such as photo capture with geotagging and point-cloud scanning, all from a single interface. Because the system is designed for users with no specialized GNSS knowledge, it dramatically lowers the barrier to adopting high-precision surveying workflows on construction and civil-engineering sites.

• High accuracy: LRTK delivers outstanding positioning precision, providing a stable centimeter-level fixed solution. Higher-end models—such as the LRTK Pro2—support CLAS augmentation signals from Japan’s Quasi-Zenith Satellite System (QZSS “Michibiki”), enabling satellite-based corrections even in remote mountain areas with no internet coverage. Some units also feature built-in tilt compensation, automatically correcting the tip coordinates when the survey pole is inclined, which is invaluable on obstructed job sites. Field tests show that, by using the LRTK app’s averaging function, single-point accuracy can be stabilized to within just a few millimeters to about one centimeter.

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Use case: LRTK excels in a variety of field scenarios. For instance, in urban areas crowded with high-rise buildings, it is used to tag infrastructure-inspection photos with precise coordinates and manage them in the cloud, linking each image to its exact map location.

In mountainous surveys, CLAS augmentation lets crews obtain a stable fixed solution even where cell service is unavailable, aiding the maintenance of roads and bridges. On highway-infrastructure inspections, workers can wear a helmet-mounted LRTK unit and simply walk the site, the system automatically logging trajectories and positions while their hands remain free for elevated tasks. At construction sites, operations such as stake-out or as-built measurement—once handled by specialist survey teams—can now be performed directly by site managers with an LRTK device, measured on the spot and shared to the cloud for real-time progress tracking.