What Is Public Surveying DX Led by Local Governments?
Public surveying DX refers to the integration of digital technologies into the surveying operations conducted by local governments, aiming to fundamentally transform and streamline these processes. Traditional surveying work, which once required significant time and manual effort, can now be greatly improved through the use of satellite positioning systems like GPS and GNSS, drones, and 3D measurement technologies.

Among these, RTK-GNSS stands out. It uses a real-time correction method involving a base station placed at a known point and a moving rover unit. While standalone GNSS typically has errors of several meters, RTK enables centimeter-level positioning accuracy. By combining RTK technology with cloud services, local governments can now instantly share and analyze survey data directly from the field. This has accelerated the digital transformation of infrastructure management tasks across municipalities.

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As part of efforts to promote digitalization among local governments, the national government is also encouraging the use of ICT-based surveying and 3D design data through initiatives such as "i-Construction." Public surveying DX using RTK is part of this broader trend, transforming traditional survey methods—once reliant on paper maps and manual labor—into real-time, high-precision operations.

For example, the nationwide network of electronic reference stations developed by the Geospatial Information Authority of Japan (GEONET), a GNSS Continuously Operating Reference System, serves as the foundation for network-based RTK. By receiving correction data via the internet, it enables consistent centimeter-level positioning accuracy anywhere in Japan.

Moreover, receivers compatible with Japan’s Quasi-Zenith Satellite System “Michibiki” and its CLAS (Centimeter Level Augmentation Service) are now available, allowing users to obtain high-precision correction signals directly from satellites—even in areas without mobile coverage.

Through the combination of national infrastructure and cutting-edge technology, public surveying DX in municipalities is achieving both labor-saving and advanced surveying operations.

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Traditionally, the workflow consisted of on-site surveying, manual data processing, and then drawing creation. However, with RTK-GNSS and cloud integration, high-precision data can now be captured directly in the field and immediately used to generate digital maps and 3D models, enabling real-time information sharing with relevant departments. By digitizing the entire workflow in this way, it is possible to achieve both improved survey accuracy and reduced operational time.

* For those who would like to learn more about the basic principles of RTK and how it differs from standard GNSS positioning, please refer to our in-house column article: “What is RTK? The Basics of Real-Time Kinematic Positioning.”

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Use Cases of RTK Surveying Technology
Let’s take a look at some real-world scenarios where RTK surveying technology is being utilized by local governments and construction sites. RTK has become deeply integrated into field operations in various forms—from handheld GNSS receivers used by ground surveyors to being mounted on drones flying overhead.

The receiver captures signals from GNSS satellites via the antenna on the top, while the lower unit processes correction data received from the base station. In situations where surveyors previously used transits and leveling rods to measure each point, equipment like the one shown in the photo enables real-time coordinate acquisition while moving, allowing for efficient surveying of numerous points. The collected data is immediately displayed on a tablet device, enabling instant drafting and cloud sharing.

Beyond on-site surveying as described above, RTK's high-precision positioning is being applied in a variety of public works scenarios. The following are three representative use cases: aerial drone surveying for terrain mapping, inspection and maintenance of infrastructure facilities, and disaster prevention and response.

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Topographic Surveying with Drone Aerial Photography and RTK Positioning
In recent years, aerial surveying using drones (unmanned aerial vehicles) has been increasingly adopted in public works projects across Japan. By equipping drones with high-resolution cameras and RTK-enabled GNSS receivers, it is possible to add centimeter-level positioning data to photos captured from the air.

Traditionally, converting aerial photographs into maps required placing numerous known reference points on the ground—known as Ground Control Points (GCPs)—to correct positional accuracy. However, with RTK drones, the number of required ground control points can be significantly reduced while still achieving the necessary surveying accuracy.

For example, drones equipped with built-in RTK modules—such as DJI's Phantom 4 RTK—can perform real-time position correction during flight and generate orthophotos and point cloud data with centimeter-level accuracy, even without post-processing. As a result, even large-scale survey sites can be mapped with high precision by a small team in a short amount of time, dramatically improving the productivity of public surveying.

Additionally, data collected by RTK drones can be immediately shared and analyzed via the cloud. Right after a flight, municipal departments or design firms can access the data, enabling faster decision-making. For example, in topographic surveys of planned development sites, what once required survey crews several days to measure and draft before distributing to stakeholders can now be replaced by a detailed terrain model delivered on the same day via drone.

This approach is also highly effective in emergency situations. Drones can capture post-disaster terrain changes immediately, allowing authorities to quickly begin planning recovery efforts. High-precision aerial surveying is fundamentally transforming how surveying is conducted in public works projects.

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RTK’s Contribution to Infrastructure Inspection and Maintenance
RTK positioning is also being applied in the maintenance and inspection of infrastructure such as roads, railways, and water and sewage systems. Municipalities are responsible for the daily inspection and repair of numerous infrastructure assets—including streetlights, traffic signs, guardrails, and bridge components—and accurate location data greatly enhances this work.

By using RTK-enabled devices, for example, an inspector who identifies a malfunctioning streetlight can simply take a photo, which is automatically tagged with latitude, longitude, and timestamp information and stored in the cloud. Later, when another staff member is dispatched to the site, they can navigate directly to the exact equipment using the recorded coordinates displayed on a smartphone map—eliminating the risk of getting lost on-site.

In this way, by digitalizing infrastructure management operations with RTK, information that was once dependent on individual staff knowledge can now be shared across the organization, enabling more efficient and reliable maintenance workflows.

Furthermore, high-precision positioning data is highly effective in detecting subtle displacements and long-term changes in infrastructure assets. For example, by regularly conducting RTK surveys on bridge piers or retaining walls, even slight subsidence or deformation can be identified as differences of just a few centimeters in the data. Monitoring these changes over time allows for the early detection of areas that require repair.

In fact, a solution case from the Nippon Steel Group reports efforts to digitalize the operation and management of urban infrastructure—such as water and sewage systems, community buses, and garbage trucks—by integrating RTK, IoT sensors, and GIS. With the introduction of such high-precision positioning technology, infrastructure inspection and maintenance is shifting from a reliance on "intuition and experience" to a data-driven model of smart asset management.

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The Importance of High-Precision Positioning in Disaster Response
In the field of disaster response—such as during earthquakes and heavy rain events—high-precision positioning technologies, including RTK, play a vital role. When a large-scale disaster occurs, local governments must quickly conduct on-site assessments to understand the situation and estimate damage. By deploying RTK-enabled surveying equipment or drones, they can rapidly generate detailed current-condition maps and 3D models of the affected areas, gaining valuable insights to support rescue and recovery efforts.

For example, in mountainous regions affected by landslides, drone surveys can safely capture data from dangerous areas that are otherwise inaccessible on foot. The collected point cloud data can be used to calculate the volume of fallen debris, or to quantify changes before and after the disaster by comparing with satellite images or existing topographic maps. Such detailed disaster response analyses are made possible through the use of high-precision positioning.

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RTK is also highly useful in disaster prevention. In monitoring river embankments and steep slopes, fixed-point GNSS receivers are increasingly being used for continuous monitoring to detect abnormalities by comparing data against baseline conditions. While ground deformation was traditionally measured at intervals using leveling or optical surveys, RTK now enables continuous and automated monitoring—making it possible to catch early warning signs of potential disasters.

In fact, national and local governments are increasingly incorporating GNSS-based displacement monitoring systems into their disaster prevention infrastructure, alongside seismometers and rain gauges. As high-precision positioning technology becomes more widespread, it is expected to play a key role in building safer, more resilient communities.

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Key Considerations for Municipalities Implementing RTK
When incorporating advanced RTK surveying into municipal operations, it is important to keep certain points in mind. To maximize the benefits of introducing this new technology, the following considerations should be carefully addressed.

• Verify Operating Conditions: Since RTK positioning relies on satellite signals, it is important to be mindful of obstructions and multipath effects caused by surrounding buildings or trees. In urban areas with tall buildings or forested mountainous regions, satellites may not be adequately captured, and reflected signals can reduce accuracy. Therefore, for critical surveys, it's essential to conduct a test positioning session on-site in advance to verify whether the required accuracy can be achieved. If necessary, consider options such as adding additional base stations, using correction data services, or combining RTK with ground-based surveying methods to compensate for poor positioning conditions.

• Selecting Equipment and Services: To utilize RTK, you need a basic set of equipment including a GNSS receiver (rover), a base station, and a communication method to connect them. When selecting these components, consider the approach best suited to your use case. For example, in urban or wide-area environments, network-based RTK (such as VRS) using cellular networks is convenient. However, in mountainous regions or areas with poor coverage, you may need to set up a simple local base station or choose a receiver compatible with Japan’s unique satellite augmentation system, CLAS, provided by Michibiki. In recent years, RTK devices integrated with smartphones or tablets have also become available, allowing for easy on-site deployment. Select the most appropriate equipment and service based on your municipality’s budget and the skill level of the personnel involved.

• Human Resource Development and Operational Framework: When introducing new surveying technologies, it is essential to also invest in training the personnel who will operate them in the field. While RTK surveying has become increasingly automated and user-friendly, having technicians who understand the underlying positioning principles and potential pitfalls provides greater confidence in troubleshooting and system reliability. Providing hands-on training for municipal staff or establishing a support system with surveying consultancy firms during the initial phase of implementation can be highly effective. Additionally, simply obtaining high-precision data is not enough—it must be properly utilized. It’s important to establish mechanisms that link acquired location data with other systems such as GIS databases or CIM (Construction Information Modeling). Creating an environment where relevant departments can share data—through cloud storage or dedicated systems—is also key to maximizing the value of RTK implementation.

• Balancing Cost and Benefit: While RTK equipment and services require an initial investment, the cost of receivers has been decreasing in recent years, lowering the barrier to adoption. A wide range of options is now available, from affordable smartphone-mounted units to high-performance models capable of long-range operation. When considering implementation, evaluate the cost-effectiveness by estimating quantifiable benefits—such as reduced labor costs through improved operational efficiency, or fewer rework incidents due to higher survey accuracy. Additionally, government grants or subsidy programs may be available, so staying informed and making well-informed investment decisions is key.

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Municipal RTK Positioning Solution with LRTK
For municipalities promoting RTK surveying and digital transformation (DX), the LRTK series is a powerful ally. LRTK is an integrated solution that combines an RTK-GNSS receiver with a dedicated smartphone app and cloud service, designed to make centimeter-level positioning easy to adopt—even for those using RTK for the first time.

By transforming what was once expensive and technically complex high-precision GNSS surveying into an accessible, user-friendly tool, LRTK supports the digital transformation of municipal field operations.

The LRTK series offers a versatile lineup, including the LRTK Phone, a compact and lightweight device that attaches to a smartphone; the LRTK Pro2, an all-in-one receiver ideal for outdoor site use; and the LRTK Helmet, which allows for hands-free surveying simply by walking, mounted on a worker’s helmet. With various form factors available, users can choose the best option for their specific needs—whether it's a municipal staff member carrying a unit for routine inspections or a surveying company conducting large-scale 3D measurements under contract.

A shared platform, LRTK Cloud, is also provided, enabling instant sharing of collected field data within government offices, easy comparison with historical data, and seamless integration with other systems.

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Here are some key LRTK features particularly useful for municipalities.

• Geotagged Photo Function – By simply taking a photo of a facility or inspection point, the location (latitude and longitude), timestamp, and any notes are automatically recorded and saved. The captured images can be shared via the cloud, and with just one click, users can compare them with past photos taken at the same location. This greatly simplifies record-keeping for inspection tasks and reduces the workload involved in preparing reports.

• Coordinate Navigation Function – Workers can be guided via smartphone to pre-registered locations. For example, even if a new staff member is sent to a repair site, centimeter-level destination accuracy and navigation are provided on the map app, minimizing the risk of getting lost in the field. Even in areas with unstable satellite reception, standard GPS accuracy ensures that their location can still be tracked, allowing users to maintain spatial awareness even in places like tunnels.

• 3D Point Cloud Scanning Function – By simply pointing the LRTK device, surrounding terrain can be scanned as point cloud data. Each captured point is assigned centimeter-level position coordinates (latitude, longitude, and elevation), allowing multiple scans taken from different locations to be accurately aligned and merged later. On-site measurements—such as calculating distances between two points or estimating the volume of embankments—can be completed without specialized surveying equipment, making it possible to perform essential measurements directly in the field.

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As demonstrated, LRTK is a powerful solution that delivers high-precision positioning technology in an easy-to-use format, driving the digital transformation (DX) of surveying and maintenance operations within municipalities. Its adoption is rapidly expanding across infrastructure management and construction sites nationwide, with users praising its convenience and reliability—captured in the concept of “turning a smartphone into a surveying device.”

LRTK enables municipalities to perform surveys in-house that were previously outsourced to specialists and replaces paper-based field notes with digital records that can be leveraged for analysis. The benefits extend across multiple operational areas.