Field-Ready RTK GPS Comparison Guide: A Comprehensive Guide for Practitioners from Equipment Selection to Operation

We often hear from field personnel that they want to introduce RTK GPS equipment but don’t know which device to choose. The types, functions, and price ranges of devices vary widely, and in reality it is difficult to judge from catalog specifications alone whether a device will suit the field. This article organizes the key selection points for RTK GPS equipment and systematically explains the knowledge field personnel need, from equipment selection to stable operation after deployment.

Table of Contents

• Types and forms of RTK GPS equipment

• Major checklist items for equipment selection

• Comparing network RTK services and how to choose

• Practical points to stabilize field operations

• Device-specific spec comparisons and selection examples

• Making LRTK standard equipment on site

Types and Configurations of RTK GPS Equipment

RTK GPS equipment comes in several types, and it is important to select one according to the intended purpose and the site environment.

The pole type (rod type) is the most standard form, where an RTK receiver antenna is mounted on the tip of a survey pole and the pole is set up on the measurement point to take measurements. It supports a wide range of tasks such as land surveying, boundary confirmation, staking, and route surveying. Some devices have an integrated controller (data collector).

The backpack type is a configuration in which the receiver and power supply are stored in a backpack and measurements are taken while carrying it on the back. It is suitable for applications that involve continuous measurement while walking long distances, such as forest surveys, coastal topography surveys, and pipeline route inspections.

The drone-mounted type is a compact, lightweight receiver module integrated into a drone's airframe, used to improve the accuracy of aerial photogrammetry and to provide high-precision positioning control for autonomous drone flight.

The smartphone-linked model is a compact RTK receiver module that attaches to a smartphone (such as an iPhone). It requires no dedicated controller, can be operated from an app, and is notable for its low-cost deployment.

Primary Checklist Items for Equipment Selection

We will organize the main items to check when selecting RTK GPS equipment.

The supported satellite systems and the number of receiver channels directly determine positioning accuracy and stability. Multi-GNSS support — including GPS, GLONASS, Galileo, Michibiki (QZSS), and BeiDou — is now the standard. The greater the number of receiver channels, the more satellites can be processed simultaneously, improving stability in mountainous and urban areas.

Confirm the method for receiving correction data. Check whether it supports network RTK (via NTRIP), whether it can communicate via a built-in or external SIM card, and whether it supports radio communication (UHF/LoRa, etc.) for single-base-station RTK, according to the field environment.

IP waterproof and dustproof ratings are essential items to verify for field equipment. In rainy or muddy environments, IP67 or higher (water resistance that can withstand temporary immersion) is recommended. IP65 (dustproof and protected against water jets) is sufficient for light outdoor rain.

Battery life affects continuous working time in the field. Choosing a model that can operate continuously for 8 hours or more from a full charge reduces the risk of running out of battery during a day of work. It is also reassuring to include models that support external batteries among your options.

For data recording and output formats, verify whether it supports formats used in downstream processes, such as RINEX, CSV, Shapefile, and LAS. Whether data integration with CAD systems, GIS software, and design management systems is straightforward is also an important point.

Comparison and Selection of Network RTK Services

When operating RTK GPS equipment in Japan, choosing which network RTK service to use is also an important decision.

Correction data distribution services that use the Geospatial Information Authority of Japan's electronic reference points (provided by private companies) cover major areas nationwide and offer stable quality. Because mountainous areas and remote islands can include regions with a low density of electronic reference points, it is necessary to check the coverage of your work area in advance.

Private RTK network correction services sometimes install their own observation points in addition to electronic reference stations, and some aim to improve accuracy in specific regions. Pricing structures vary by service, including annual flat fees, monthly subscriptions, and usage-based charges.

Along with the radio conditions in the work area, also check the signal conditions of the carrier you are using. Choosing a SIM from a carrier that guarantees a stable LTE or 5G connection on site will lead to more stable reception of correction data in the field.

Practical Points for Stabilizing On-site Operations

Even if you have the equipment, inappropriate on-site operational methods can lead to problems such as poor accuracy or failure to obtain a FIX solution. We will introduce practical points for stable operation.

Before starting work, perform equipment checks to confirm battery level, network connection, reception of correction data, and acquisition of a FIX solution. In particular, confirmation of FIX solution acquisition is of the highest importance; as an absolute basic rule, do not begin measurements while in a FLOAT solution or SPPS state.

As an antenna installation precaution, keep the antenna horizontal in as open an area as possible. Multipath tends to occur near power lines, steel frames, and large vehicles, so keeping the antenna away from such obstacles will enable more stable reception.

As part of regular calibration and equipment updates, keeping the receiver firmware up to date ensures support for new satellite signals and the application of bug fixes. It is also recommended to perform accuracy checks (comparison with known points) at least once a year to check for any degradation in accuracy due to equipment aging.

Comparison of Equipment Specifications and an Example of Selection

When selecting equipment in practice, the most suitable option depends on what you prioritize.

When the primary purpose is specialized surveying work (control point surveying / route surveying), dedicated surveying equipment with a high channel count, multi-frequency support (L1/L2 or L5), and high-precision antenna phase center characteristics is suitable.

For construction management, site condition verification, and routine position checks, network RTK-capable devices that are easy to operate and cost-effective are suitable. Smartphone-connected models let you utilize existing devices and reduce acquisition and deployment costs.

When the purpose is installing ground control points and managing flights for drone surveying, compact, high-precision equipment that can obtain a FIX solution quickly has a major impact on work efficiency.

Make LRTK standard equipment on site

LRTK (iPhone-mounted high-precision GNSS positioning device) achieves network RTK positioning simply by attaching to an iPhone. No dedicated controller or large antenna is required, and because it can be used together with the iPhone that field personnel carry daily, the burden of carrying equipment is minimized.

It supports network RTK and can obtain stable FIX solutions across a wide area in Japan. Measurement, recording, and output can be done intuitively from the app, so construction managers, inspectors, and survey personnel without specialized surveying training can be put to work immediately. Deploying devices to multiple staff can be done at lower cost than with dedicated equipment, helping to promote digitization across the entire site.

Selection of RTK GPS equipment should be made by comprehensively considering on-site work tasks, required accuracy, the communication environment, and implementation costs, as this leads to stable long-term field operations. Using the selection checklist and operational points introduced here as a reference, establish the equipment and operational framework best suited to your company’s sites.