One-Person RTK Layout: A Practical Checklist

On construction and civil engineering sites, surveying work has traditionally required multiple people. Typically, one person operates surveying equipment such as a total station while another person stands at a distance holding a rod for staking or marking—a two-person team. This method requires time and effort from setup to teardown, and on large sites or where there are many points to stake, it is not uncommon for the work to take an entire day. Manual measurements also carry the risk of human errors such as misreading or misrecording values, and any mistakes require re-surveying, making the process inefficient.

In recent years, the construction industry has faced severe labor shortages and an aging workforce, driving demand for labor-saving and efficiency-improving measures so that sites can be managed with a limited number of workers. Digital productivity improvements, such as the Ministry of Land, Infrastructure, Transport and Tourism’s i-Construction initiative, are major themes. With the decline in experienced surveyors, it is becoming increasingly difficult to continue “surveying that relies on people.” Therefore, expectations are growing for one-person-complete surveying (one-man surveying) that leverages the latest technology.

The spread of RTK (Real-Time Kinematic), a high-precision GNSS positioning technology, has made staking and layout work on construction sites dramatically more efficient. Tasks that previously required multiple people and considerable time—such as setting out buildings and structures or staking pavement lines—can be performed quickly and accurately by a single person using RTK. Because three-dimensional coordinates can be obtained in real time, you can verify as-built positions including elevation on the spot, minimizing construction errors and rework. For infrastructure inspection surveys as well, one person can record high-precision as-built data, aiding efficient maintenance management.

This article starts with the basics of RTK and then walks step-by-step through performing RTK layout work alone, from preparation to completion. It includes comparisons with traditional methods and on-site cautions, providing a practical checklist useful for beginners to intermediate users. At the end of the article, we introduce an easy surveying solution called “LRTK” that enables high-precision positioning more easily.

Table of Contents

• What is RTK?

• Benefits of performing RTK layout alone

• Step 1: Preparation (survey planning and equipment check)

• Step 2: Setting up the base station or preparing correction data

• Step 3: Configuring the RTK receiver (rover) and starting positioning

• Step 4: Marking design positions (staking)

• Step 5: Verifying survey results and finishing tasks

• Key points for successful RTK surveying

• Conclusion: Simple surveying with LRTK

• FAQ

What is RTK?

RTK (Real-Time Kinematic) is a technology that corrects GNSS (satellite positioning) errors in real time to measure positions with centimeter-level accuracy. Standalone GPS positioning typically produces errors on the order of several meters (several ft), but RTK achieves dramatically higher accuracy by performing relative positioning using two receivers to cancel error sources.

RTK positioning generally consists of two GNSS receivers—the base station and the rover—and a communication link between them. The base station is set up at a precisely known coordinate and receives signals from multiple satellites simultaneously with the rover. The base station calculates positioning errors (correction data) and sends them to the rover via communication; the rover applies those corrections to its own observations, canceling error sources and obtaining high-precision positions.

A key feature of RTK is that it provides high-precision positioning in real time. Under good conditions, horizontal errors are roughly 2–3 cm (0.8–1.2 in), and vertical errors are about 3–5 cm (1.2–2.0 in) (standalone GPS positioning errors are on the order of several meters (several ft)). This enables precise layout that was previously difficult and dramatically improves construction accuracy. Recent receivers also support multi-GNSS (GPS, GLONASS, Galileo, QZSS/Michibiki, etc.), allowing the use of many satellites and making the acquisition of a FIX solution (high-precision fixed solution) more stable. Combining multiple satellite systems improves positioning continuity even when satellite geometry is unfavorable, reducing dependence on any single unstable satellite and helping maintain accuracy.

RTK systems are broadly classified into two types: standalone RTK (base & rover) and network RTK. Standalone RTK involves placing your own base station on site and sending corrections to the rover via radio, while network RTK receives correction information over the internet from national or commercial base-station networks (Ntrip services). In network RTK (e.g., VRS), users do not place a physical base station on site; instead, the service provides virtual base station data near the user. Both approaches share the same principle—using correction data from a base station to correct rover positioning errors—and the accuracy improvement itself does not differ between them.

Benefits of performing RTK layout alone

Introducing RTK to layout tasks on construction sites yields many benefits not available with traditional methods. First and foremost is a dramatic improvement in efficiency. Staking and marking with a total station require multiple personnel to maintain line-of-sight, but with RTK, one person carrying a receiver can handle wide-area layout work. For example, baseline point setup and placement of survey stakes that used to take three people half a day can be completed quickly by one person with RTK. This reduces personnel needs and shortens schedules, significantly boosting productivity on sites suffering chronic labor shortages.

Second, the ability to obtain three-dimensional coordinates in real time is a major advantage. Using network RTK, you can obtain absolute coordinates in a global geodetic system (for example, plane rectangular coordinates based on JGD2011 in Japan) simultaneously with surveying, reducing the need for separate leveling to measure elevations or converting to local coordinates. For projects planned in a public coordinate system, RTK lets you obtain those coordinates directly on site, streamlining elevation marking tasks.

Furthermore, RTK is well suited to wide-area sites and environments with poor line-of-sight. Optical surveying equipment requires direct line-of-sight, but RTK only needs satellite signals, allowing positioning of points beyond obstacles and staking at night. Once the base station is set up, the operator carrying the rover can freely move around the site to measure and set points sequentially, greatly increasing work speed compared to before. High-precision RTK positioning minimizes construction errors and rework, contributing to final quality assurance.

Step 1: Preparation (survey planning and equipment check)

Survey planning and data preparation: Before starting RTK layout work, careful preplanning is essential. Extract and organize the coordinates of points and lines to be placed from the design drawings or CAD data in advance. List coordinates that require staking or marking—such as building grid intersection points, corners of structures, and roadway centerline points—and prepare them in data formats that field controllers or surveying apps can read (e.g., CSV coordinate lists or DXF CAD files).

Confirm coordinate systems and survey datums: Check which coordinate system is used in the design. Determine whether design coordinates are based on a global geodetic system (e.g., plane rectangular coordinates based on JGD2011 in Japan) or a local site coordinate system. It is important to unify the reference coordinate system so that RTK-obtained positions match the design drawings. For projects planned in a public coordinate system, using network RTK allows you to obtain public coordinate values directly. For sites using a local coordinate system, you may need to perform a localization (onsite calibration) using known points to align RTK results with the design coordinates. Share known point information or transformation parameters in advance if available.

Equipment check: Inspect and prepare the full set of RTK surveying equipment in advance. Specifically: RTK-capable GNSS receivers (for base and rover), GNSS antennas, controller devices (survey tablets or data loggers), tripods, survey poles, batteries and chargers, and communication devices (radios or mobile hotspot routers). Check battery levels and spare power supplies, confirm firmware and apps are up to date, and verify OS updates on smartphones or tablets if used. If using network RTK, complete the SIM card data plan and connection settings in advance so you can connect to the internet smoothly onsite.

Assess satellite reception conditions: It’s helpful to predict satellite geometry and the number of visible satellites ahead of time. Use a GNSS planner to check how many satellites will be available at the planned survey date and time and whether the expected DOP values (an indicator of positioning quality) are favorable. Especially in urban canyons or mountainous sites, the number of usable satellites can vary by time of day, so avoid times when geometry is poor and, if possible, schedule work when satellite conditions are favorable to stabilize accuracy.

Safety measures and prior notification: When working alone, pay close attention to safety. On sites with heavy machinery or busy roads, wear helmets and high-visibility vests and set cones around work areas. Avoid becoming so absorbed in device screens that you lose situational awareness—stop periodically to check your surroundings and take breaks as needed. Also notify the site supervisor in advance that RTK surveying will be conducted, and obtain permission for base station placement and confirmation of radio frequency bands to be used. Before work begins, share the day’s plan and locations internally and establish regular check-ins and emergency contact methods—these preparations are especially important when working alone.

Step 2: Setting up the base station or preparing correction data

Once preparations are complete, set up the RTK base station on site and start supplying correction data to the rover. Operationally, you will choose either (A) setting up your own base station, or (B) receiving correction information from a network RTK service. The procedures and key points for each are as follows.

(A) Setting up your own base station: First, select a suitable base station location. Ideally choose a high spot with a clear view of the sky and no surrounding obstructions such as buildings or heavy equipment, allowing the antenna to see the sky 360 degrees. Mount the GNSS antenna on a tripod on stable ground and secure it so it won’t topple. Power on the base receiver and input the precise known coordinates of the base point that you prepared in advance (if no known point is available, you can assign a provisional coordinate by performing a static observation for several minutes on site, but preparing known coordinates beforehand is preferable). For elevation, if the site is tied to official benchmarks, input the official elevation; otherwise, set the elevation calculated from the GNSS ellipsoid height. The base station will continue fixed surveying at the set coordinate and will generate correction data (differential information) in real time.

Next, establish communication from the base to the rover. In a private base station setup, correction information is typically transmitted via low-power UHF radio or LoRa radios. Power on the radio transmitter at the base and match frequency and channel settings so the rover can receive it. If the site is large and radio coverage is limited, prepare repeaters or mount the antenna higher to secure the communication range. Also make sure the radio equipment you use complies with radio regulations and is authorized for use (in Japan, low-power radios or licensed professional radios are common).

(B) Using network RTK: In this approach, no physical base station is placed on site. Instead, connect to a GNSS base station network (Ntrip service) provided by government or commercial operators via the internet and receive correction data. On the controller device (survey app), configure the connection settings for your subscribed RTK service. Enter Ntrip credentials such as user ID and password, the server IP/port, and the mount point (the virtual base station type), and log in via mobile data or site Wi‑Fi. Once connected, the service will generate virtual base station data near the user and stream corrections in real time. When the rover receives these corrections, RTK positioning can begin immediately.

Be mindful of the site’s communications environment when using network RTK. In mountainous areas or underground spaces where cellular signals are unavailable, internet-based correction reception is not possible. In such areas, prepare alternatives in advance. One option is switching to a private base station and radio transmission; another is using the Japanese Quasi-Zenith Satellite System “Michibiki”’s CLAS (Centimeter-Level Augmentation Service). CLAS-capable RTK receivers can obtain correction signals directly from Michibiki satellites and achieve centimeter-level positioning in real time even outside cellular coverage. Choose the correction method that best fits your用途 and site conditions.

Step 3: Configuring the RTK receiver (rover) and starting positioning

With the base station ready and corrections being broadcast, set up the rover RTK receiver. The rover equipment is what the operator carries to perform positioning and staking. Typically a GNSS antenna-integrated receiver is mounted on top of a survey pole (staff), and the pole tip is placed on the ground to measure points.

Powering up and confirming FIX: Turn on the rover receiver and confirm that it is receiving correction data correctly from the base. In a private base setup, power the radio receiver on the pole; in a network setup, connect the controller to the internet and launch the RTK app. If corrections are arriving correctly, you should see an increase in the number of tracked satellites and the RTK solution transition from Float to Fix on the GNSS status screen. “FIX” indicates that real-time corrections are active and high-precision positioning is established. For first-time users, achieving FIX may take from several tens of seconds to a few minutes, but with sufficient satellite visibility and stable communications, FIX is generally obtained quickly.

Antenna height and positioning parameter settings: To obtain accurate coordinates, check rover settings. If using a survey pole, measure the antenna height (the vertical distance from the antenna reference point to the ground) and input it into the receiver or app. An incorrect antenna height entry will introduce vertical offsets in the output coordinates, so be careful. Also verify that the positioning mode and the output coordinate system set in the receiver/software match your survey plan (e.g., set the output coordinates to the designated plane rectangular coordinate system and enable or disable geoid corrections as required). Apply an appropriate geoid model for your region so that converted ellipsoid heights yield correct orthometric elevations.

Accuracy check with known points: Shortly after starting RTK, verify accuracy using nearby known points if available. If there are existing control points or known coordinate stakes on site, measure them with the rover and compare the obtained values with the known values. If differences are within a few centimeters (within a few inches), the system is functioning correctly. If large discrepancies occur, investigate potential causes—incorrect base coordinates, device settings, or communication issues—and do not proceed with full layout until resolved. Also leave the rover stationary for a while to confirm that the FIX solution remains stable (watch for temporary loss to Float due to satellite disruptions or radio interference). If FIX is unstable, try reorienting the antenna, moving away from reflective sources, or rechecking the base-rover communications.

Using tilt compensation: Many modern RTK receivers include tilt compensation functionality. This allows accurate positioning of the pole tip even when the pole is not perfectly vertical—useful near obstacles where you cannot hold the pole upright. If your rover supports this, perform tilt sensor calibration before work and enable the feature. This ensures the ground point at the pole tip is correctly recorded even when the pole is tilted, making point observations and staking near walls or in tight spaces easier.

Step 4: Marking design positions (staking)

Loading design data: Once high-precision RTK positioning is stable, begin staking. On the controller (survey app), load the design coordinate data prepared in advance for the layout. Load project data such as lists of coordinates to be set out—e.g., building foundation grid intersections, external corner points of structures, and groups of roadway centerline points. Each point should have an ID or description from the drawing so that the operator does not get confused on site.

Guidance to target points: When you select a target point, the RTK system displays the horizontal distance, direction, and vertical offset between the current rover position and the target coordinate in real time. The screen may show messages like “You are X.X m east and Y.Y m north of the target” and “Your height is △.△ m lower than the target.” The operator moves the pole while watching this guidance until the distance approaches zero. Many receivers or apps display arrows or target markers to intuitively indicate the direction of the specified coordinate. Follow the guidance and move the rover until the deviation is minimal.

Marking at the specified location: When the screen indicates that you are approximately 0 m in all horizontal directions and the height difference is within allowable tolerance (for example, within a few centimeters (within a few inches)), place a permanent or temporary mark. Firmly set the pole tip on the ground to prevent movement during marking. Marking methods vary by site: drive a wooden stake and mark the head; draw a mark on concrete with chalk or spray; leave a nail and tape on asphalt; and so on. If necessary, record the point name or design elevation near the mark so it is clear to subsequent crews.

Multiple points and wide-area layout: When multiple design points must be set, repeat the steps above for each point. Once the base station is established, RTK allows freedom of movement across the site without line-of-sight constraints, enabling efficient point巡回. A single operator can cover large areas without intermediate line-of-sight stakes or a second person. Organize the order efficiently—e.g., work from the back of the site toward the front or group points by building—and proceed. Because RTK positioning only requires satellite reception, staking can also be performed at night with sufficient lighting (note that visible satellite counts may decrease at night, so take care).

Layout of lines and elevation references: RTK can be used not only for points but also for lines and planes. For example, to mark a roadway or conduit centerline on site, you can drop points at set intervals to mark the line, or move the rover continuously while observing the current position and draw a line with chalk or lime. When setting up horizontal boards (string lines) for building layout, first use RTK to set exact reference points and then span boards between them to achieve accurate elevation and positional control in one step. With centimeter-level RTK accuracy, you can faithfully reproduce complex grid lines or sloped alignments on site, facilitating subsequent formwork and paving operations.

Step 5: Verifying survey results and finishing tasks

Reconfirm critical points: After staking or marking all planned points, verify the results. Double-check especially critical points by re-measuring them to prevent mistakes. For instance, measure critical control stakes or structural center points again with the rover and compare with the design coordinates. If the second measurement matches the first within a few centimeters (within a few inches), it’s acceptable. If a large discrepancy appears, investigate potential causes such as temporary satellite reception issues or incorrect staking, and rework or inspect as necessary. Even with RTK, human double-checks increase reliability.

Protect marked points: To prevent stakes or marks from being lost during construction, make them conspicuous and protected. Tie colored flags, surround stakes with wooden frames, or wrap tape around stake heads to clearly indicate “control point here” so other workers do not accidentally move or damage them. On sites with heavy machinery, take measures so that points are not obliterated by tire tracks or equipment.

Save survey data: Save and back up the survey logs and measured coordinates recorded in the controller or app. Many RTK systems automatically log residuals between design and measured values, FIX/Float states at each point, timestamps, and more when staking. Upload these logs to the cloud onsite or transfer them to a PC after returning to the office for safekeeping; they are useful for producing deliverables or reports later. On jobs requiring electronic submission, RTK survey records serve as evidence for each point.

Equipment teardown and reporting: If you set up your own base station, dismantle it at the end. Before dismantling the tripod and antenna, it’s advisable to record static observation data at the base station for several tens of minutes to verify the originally entered base coordinates (this data can be tied to electronic control points later to check differences). If everything is fine, disassemble equipment and confirm nothing is left behind. Turn off rover devices, clean off mud or dirt, and store them properly. With that, RTK-based layout surveying is complete. Finally, hand over information to the next work crew—where which stakes were placed and what the reference elevations are—so that on-site成果 are shared.

Key points for successful RTK surveying

• Secure an open sky environment: RTK depends on receiving satellite signals. Tall buildings or trees block the sky and reduce visible satellites or increase multipath (reflected) errors. Survey in as open a sky area as possible. If obstacles cannot be avoided, consider temporarily switching to another surveying method for that section (for example, use a total station for that portion). Other measures include raising the antenna to reduce low-angle signal blockage, installing a ground plane under the antenna to block low-angle reflections, or increasing the minimum elevation mask to exclude low, unstable satellites.

• Maintain communications: RTK requires continuous correction data from the base to the rover. For radio systems, avoid obstacles between the base antenna and the rover and remain within the communication coverage area. For network RTK, prepare alternatives such as CLAS or a portable Wi‑Fi hotspot for areas likely to be out of cellular coverage. If communication is lost, do not panic—stop and wait for the connection to recover and ensure FIX is obtained before resuming work (continuing to stake during communication loss can cause position errors).

• Pay attention to base station coordinates and baseline length: Always ensure that the base station coordinate entered is accurate. If the base coordinate is wrong, all points measured by the rover will be shifted by the same error. If there is any doubt, secure a verification method (e.g., tie the base to nearby active control points) or, with network RTK, measure known points with the rover before and after work to check differences. Also, keep in mind that baseline distance (distance between base and rover) is generally recommended to be within 10 km (32808 ft). Greater distances make ionospheric and tropospheric correction less effective, slowing FIX acquisition and degrading accuracy. Network RTK uses interpolated corrections from multiple nearby base stations, which helps maintain accuracy over wider areas, but standalone long baselines can lead to degraded performance.

• Implement rigorous accuracy management and double checks: Do not rely solely on machines—make it a habit to constantly monitor current accuracy status. Specifically, watch whether the controller displays a “FIX” solution or if it has dropped to “Float” or “Single.” If FIX is lost, the current results are unreliable—pause work and wait for FIX to return while checking satellite and communication conditions. Also perform spot checks by measuring known points or duplicated stakes to confirm consistency; such double checks are effective quality control. Surveying is susceptible to environmental factors, but human re-observation and cross-checking can detect and eliminate potential errors early.

• Be aware of GNSS-specific phenomena: GNSS positioning can be disturbed by solar activity or ionospheric conditions. Examples include times when satellite geometry is poor (few satellites available), days with strong ionospheric disturbances from solar flares, or environments with heavy multipath from metal structures or water. If FIX cannot be obtained or maintained due to these factors, consider temporarily suspending or postponing measurements. Because RTK provides real-time results, environmental impacts appear in real time. Flexibly adjusting schedules—e.g., “satellite geometry is poor near noon today, so move work to the afternoon,” or “re-measure this point tomorrow morning when the ionosphere is calmer”—can ultimately lead to more efficient surveying.

Conclusion: Simple surveying with LRTK

As described above, one-person RTK layout on construction sites can be performed with high accuracy and efficiency. However, depending on the site, satellite reception and reliance on communications infrastructure can be challenges. Conventional RTK equipment has also tended to be large and expensive and required specialist knowledge to operate. Recently, solutions that lower these barriers and enable anyone to perform centimeter-level positioning easily have emerged. One of these is a next-generation positioning system called LRTK.

LRTK combines a smartphone with an ultra-compact RTK-GNSS receiver. It consists of a palm-sized receiver (weighing only about 150–200g) that can be attached to a smartphone or tablet and a dedicated app, and it uses network RTK or QZSS/Michibiki CLAS satellite augmentation to obtain global coordinates on site instantly. Notably, some LRTK receivers can continue positioning even outside cellular coverage. LRTK receivers support multi-frequency GNSS and can receive corrections directly from satellites, enabling centimeter-level positioning in real time in mountainous areas where mobile coverage is absent. Operation is handled via an intuitive smartphone app, and features such as cloud data sharing, embedding coordinates into photos, and AR-guided staking simplify fieldwork. Recent models also support tilt compensation, allowing accurate correction of point positions where it is hard to hold the pole vertically.

LRTK thus covers situations that conventional RTK equipment finds challenging and is gaining attention as a simple surveying tool anyone can use. Although not omnipotent, it is a powerful option for efficiently surveying a wide range of environments—from open development sites to urban areas and mountainous terrain. Designed with the concept of “one versatile surveying device per person,” this system’s reasonable pricing has led to adoption by small and medium construction firms and surveying offices. By utilizing smart positioning devices like LRTK that bring RTK benefits to the field more easily, surveying practices on construction sites are likely to continue evolving. Consider introducing the latest tools to achieve both labor savings and improved accuracy in surveying tasks.

FAQ

Q1. What does RTK stand for, and what kind of positioning technique is it? A. RTK stands for Real Time Kinematic, a GNSS-based positioning technique that corrects satellite positioning errors in real time to achieve high-precision positions. By using two ground receivers—a base station and a rover—for relative positioning, RTK achieves centimeter-level positioning, which is far more accurate than standalone GPS.

Q2. What level of accuracy can be expected with RTK surveying? A. Under good conditions with a stable system, horizontal accuracy of about 2–3 cm (0.8–1.2 in) and vertical accuracy of about 3–5 cm (1.2–2.0 in) can be achieved. This is orders of magnitude more accurate than standalone GPS, which typically has several-meter (several ft) errors. Actual accuracy depends on satellite reception conditions and the distance from the base station; in environments with many obstructions, errors can grow to several tens of centimeters (several inches), so caution is needed.

Q3. What is needed to start RTK surveying? A. Basically, two GNSS receivers are required—one as the base station and one as the rover. In addition, a communication link between them (radio or internet) is necessary. However, if you use a network RTK service, you can survey with a single rover receiver (no private base station required). In that case, you need a subscription to the correction service and a communications device (SIM card, etc.). Other items include a survey pole or tripod, a controller device for data collection and display, and spare batteries.

Q4. How far from the base station can you survey? A. It is generally recommended to operate within a radius of 10 km (32808 ft) from the base station. Beyond that, ionospheric and tropospheric differences increase, potentially causing longer FIX acquisition times and growth of positioning errors from a few centimeters to several tens of centimeters. Standalone RTK over distances exceeding 20 km (65617 ft) becomes difficult to maintain high accuracy. Network RTK (VRS, etc.) generates virtual base station data near the user, enabling practical high accuracy over wider areas, and many examples show acceptable accuracy even tens of kilometers away.

Q5. What should I do in areas with many obstructions or where satellites cannot be tracked? A. In forests or streets of high-rise buildings with severely limited satellite visibility, RTK positioning may be difficult. Countermeasures include moving to a more open location to measure, raising the antenna, or using another surveying method for that section (e.g., a total station). If FIX cannot be obtained temporarily due to a lack of satellites, pause and wait a few minutes or change location. If still not possible, consider changing the time of day when satellite geometry improves. In tunnels or indoor spaces where GNSS is unusable, switch to non-GNSS methods (total station or IMU-equipped systems).

Q6. Can RTK surveying be done without cellular coverage? A. Yes. Where cellular signals are absent, a common approach is to set up your own base station and send corrections via radio. In Japan, using the QZSS Michibiki CLAS service is another option: CLAS-capable receivers can obtain correction signals directly from satellites without the internet, achieving real-time high-precision positioning in mountainous areas. If real-time positioning is not required, Record observations on site and post-process them later with PPK (Post-Processed Kinematic) to obtain high accuracy.

Q7. What is LRTK? A. LRTK is an ultra-compact RTK-GNSS positioning system used in combination with a smartphone. It consists of a palm-sized receiver attachable to a smartphone or tablet and a dedicated app, and it uses network RTK and satellite augmentation signals to achieve centimeter-level real-time positioning. Because some LRTK receivers can receive corrections directly from augmentation satellites even outside cellular coverage, they enable simple positioning in environments where traditional surveying was difficult. LRTK’s intuitive smartphone interface makes it easy for surveying beginners to use, and it is transforming field surveying practices.