SphereFix SP35Se RTK GNSS Rover and Base Set

Complete RTK Base and Rover System

The SphereFix SP35Se RTK GNSS Rover and Base Set provides the equipment needed to establish a local GNSS base station and survey with a separate rover. The set is intended for professionals who need centimetre-level positioning in locations where a permanent RTK network is unavailable, mobile coverage is unreliable or using an independent correction source is preferred.

One SP35Se receiver is installed over a known or temporarily established base point and transmits RTK correction data by radio. The second SP35Se is mounted on the survey pole and used as the rover. The included SphereFix C100T data controller is used to configure the equipment, manage the survey and record or stake out points in the field.

Suitable for Independent RTK Fieldwork

A rover-and-base setup gives survey teams greater control over how corrections are generated and transmitted. It can be used on construction sites, remote land surveys, agricultural projects, mines, quarries, infrastructure corridors and other locations outside dependable mobile-network coverage.

The system is suitable for topographic surveys, site control, construction layout, road and utility work, earthworks, boundary surveys, volume measurement, GIS asset collection and drone ground-control points. It can also be useful for contractors who move regularly between sites and cannot depend on the availability of a regional correction service.

1,408-Channel Multi-Constellation GNSS

Each SP35Se receiver uses a 1,408-channel GNSS engine capable of tracking GPS, GLONASS, Galileo, BeiDou, QZSS, SBAS and NavIC signals. Multi-frequency and multi-constellation tracking gives the receivers access to a broad range of satellite signals and helps support reliable positioning in real field conditions.

Having more usable satellites can improve satellite geometry and make it easier to maintain an RTK fixed solution around partial obstructions such as buildings, trees, embankments and site machinery. Positioning performance will still depend on satellite visibility, the quality of the base coordinates, radio reception, multipath and the surrounding environment.

Local Corrections Through the Integrated Radio

The SP35Se includes an integrated 410–470 MHz UHF/LoRa radio with selectable 0.5 W and 1.5 W transmission power. When one receiver is operating as the base, it can transmit correction data directly to the rover without relying on a mobile internet connection.

The specified radio range is up to 10 km under suitable open-sky conditions. In practical fieldwork, the achievable distance depends on antenna height, terrain, buildings, vegetation, interference and the radio settings used. Raising the base antenna and maintaining a clear line of sight generally improves communication. Radio frequencies and transmission power must always be configured in accordance with local regulations.

60° IMU Tilt Compensation

The rover receiver includes an integrated IMU that allows points to be measured with the pole tilted by up to 60 degrees. This reduces the need to centre the pole bubble perfectly for every observation and helps speed up routine data collection.

Tilt measurement is especially useful when measuring beside walls, fences, parked machinery, building corners, trenches or other locations where holding the pole vertically is inconvenient. It also makes fieldwork more comfortable on steep or uneven ground. Within the stated tilt range, the specified additional positioning error is less than 2 cm.

Camera-Assisted AR Stakeout

A built-in wide-angle camera supports AR real-scene stakeout. Compatible field software can place directional guidance over a live image of the site, giving the operator a visual indication of where the design point is located.

This makes it easier to approach stakeout positions than working with numerical offsets alone. The feature can save time when setting out large numbers of points and provides a more intuitive workflow for construction workers, engineers and site personnel who are not full-time surveyors.

Rugged C100T Android Data Controller

The included SphereFix C100T controller runs Android 11 and uses an eight-core processor. It provides the field interface for configuring the base and rover, entering project information, connecting to the receiver and operating compatible surveying or GIS software.

Its 5.45-inch sunlight-readable touchscreen supports outdoor use in bright conditions, while the physical keypad remains practical when working with gloves or in wet weather. Dual-SIM 4G, Wi-Fi, Bluetooth and NFC provide flexible communication options for transferring data and connecting field equipment.

The controller has IP68 environmental protection and a stated operating time of up to 18 hours. Actual battery life depends on screen brightness, mobile data use, connected devices, temperature and the applications running on the controller.

Lightweight Receivers for Daily Site Use

Each SP35Se weighs approximately 750 grams, helping reduce fatigue when the rover is carried on a survey pole throughout the day. The magnesium-alloy housing and IP68 protection are intended for regular outdoor use in dust, rain and demanding site conditions.

The internal receiver battery provides more than 16 hours of typical rover operation when using mobile communications. Runtime can be shorter when a receiver is operating as a high-power radio base, so the expected working period should be considered when planning longer projects. USB Power Delivery charging provides a convenient way to recharge the receivers between jobs.

Flexible Rover Base and Network RTK Workflows

Although this package is designed for local base-and-rover operation, the SP35Se can also receive RTK corrections through its integrated 4G modem. This means the rover may be connected to a compatible NTRIP correction service when coverage is available, while the second receiver can be retained for projects where an independent base is required.

The receivers support rover, base and static operating modes. This allows the equipment to be used for real-time surveying as well as static GNSS observations and other workflows that may require post-processing.

Construction Surveying and Setting Out

Construction teams can use the system to establish site control, position foundations, set out roads and utilities, check elevations and record completed work. Because the base remains on site and supplies corrections directly to the rover, the crew can continue working without depending on an external correction-network subscription.

The IMU and visual stakeout functions are particularly useful during construction layout. Tilt compensation helps measure points near obstructions, while the camera guidance assists the operator in navigating towards the correct design coordinate.

Land Surveying GIS and Drone Applications

Land surveyors can use the set for control surveys, topographic mapping, detail measurement, boundaries and setting out. GIS and utility teams can record accurate positions for pipes, cables, chambers, valves, poles and other assets, including work in rural areas where mobile coverage may be limited.

Drone operators can measure ground-control points and independent checkpoints for photogrammetry projects. Using a local base also provides a practical correction source for compatible UAV workflows where site-specific GNSS observations are required.

Configuration and Support from Global GPS Systems

A reliable base-and-rover setup depends on more than the receiver specification. The base position, radio frequency, communication protocol, antenna height, coordinate system and survey software must all be configured correctly for the project.

Global GPS Systems can help prepare the SphereFix SP35Se Rover and Base Set for construction, surveying, GIS or drone applications. Support is available when selecting poles, tripods, tribrachs, radio accessories, field software and coordinate-system settings, helping users start with a configuration suited to their normal fieldwork.