AlphaGeo LR9 High Performance GNSS Reference Receiver

Reliable GNSS Data for Reference Stations and Monitoring

The AlphaGeo LR9 High Performance GNSS Reference Receiver is designed for fixed installations where positioning data must be collected and transmitted continuously. Typical applications include CORS network deployment, geohazard monitoring, structural movement monitoring and permanent survey-control infrastructure.

Unlike a conventional rover receiver that moves between survey points, the LR9 is intended to operate from a known, stable location. It records satellite observations and can distribute correction data to connected GNSS rovers, software platforms or monitoring systems. This gives surveyors, engineers and construction teams a dependable positioning reference across a project area.

Multi-Constellation and Multi-Frequency Signal Tracking

The LR9 uses 1408 channels to track GPS, GLONASS, BeiDou, Galileo, QZSS and SBAS signals. Multi-frequency tracking gives the receiver more observations to work with and helps maintain stable positioning when satellite visibility or atmospheric conditions are less than ideal.

Support for modern signals such as GPS L5, Galileo E5 and E6, and multiple BeiDou frequencies makes the receiver suitable for long-term reference infrastructure. It also helps reduce the effect of ionospheric delays and multipath interference, which can otherwise affect the consistency of GNSS measurements.

Precision for Static and Real-Time Applications

For static GNSS surveying, the LR9 provides specified horizontal accuracy of ±(2.5 + 0.5 ppm) mm and vertical accuracy of ±(5 + 0.5 ppm) mm. Its specified RTK accuracy is ±(8 + 1 ppm) mm horizontally and ±(15 + 1 ppm) mm vertically.

In practical terms, static observations can support high-precision control networks and movement analysis, while RTK output can provide centimetre-level corrections for site surveying, setting out, mapping and construction measurement. RTK initialization is specified at under 10 seconds on baselines shorter than 10 kilometres when operating conditions are suitable.

Built for CORS Networks

In a continuously operating reference station, the receiver remains installed at a surveyed control point and collects GNSS observations over long periods. The LR9 supports NTRIP and TCP/IP communication together with RTCM 3.x correction formats, allowing it to form part of an internet-connected RTK correction service.

This makes it relevant to survey businesses, construction companies, public authorities and GIS organisations that want to operate a local base station or build a wider correction network. Multiple rovers can use corrections from the reference infrastructure without placing a temporary base receiver on every job site.

Continuous Deformation and Geohazard Monitoring

The LR9 can also be used as part of a monitoring system for slopes, landslides, dams, bridges, buildings and other structures. A permanently installed receiver records repeated position measurements so monitoring software can identify gradual displacement or sudden movement.

GNSS monitoring is especially useful at locations where measurements are required continuously or where regular manual surveying would be difficult. The receiver supplies the positioning data, while alarms, analysis and reporting are managed by the connected monitoring platform.

Flexible Data Communication

The receiver includes 4G mobile connectivity, 802.11 b/g Wi-Fi, an RJ45 network connection and an RS232 interface. Dedicated connections are provided for the external GNSS antenna, 4G antenna, power supply and PPS output.

These options allow the LR9 to communicate through the most practical connection available at the installation site. Ethernet can be used at permanent facilities, while 4G can connect remote stations where a wired network is unavailable. NTRIP support enables correction data to be sent through the internet to compatible field receivers.

Local Storage for Long-Term Observation Data

Integrated 32GB storage records raw GNSS observations at a published sampling rate of 1Hz. AlphaGeo specifies capacity for up to 180 days of continuous raw-data recording at this rate, supported by circular FIFO storage management.

Local recording provides a valuable backup when a network connection is interrupted. The stored observations can also support post-processing, quality checks and longer-term displacement analysis.

Low-Power Operation and Backup Battery

The LR9 operates from a 9–36V DC supply and has a stated power consumption of no more than 2.5W. A built-in 20,000mAh battery supports continued operation during temporary power interruptions and can simplify deployment at sites using solar or other limited power sources.

Low consumption is particularly useful for remote reference and monitoring stations, where dependable operation matters more than frequent access to the equipment.

Designed for Permanent Outdoor Installations

The IP67-rated enclosure protects the receiver against dust and temporary water immersion. It is specified for operation from -40°C to +75°C and for storage from -55°C to +85°C. The unit measures 196 × 145 × 62 mm and weighs no more than 1.5kg.

A 2.42-inch industrial OLED screen displays system information directly at the receiver. Physical navigation buttons and separate power, Wi-Fi, data and satellite indicators allow technicians to check the station during installation or maintenance without relying entirely on an external controller.

Applications

• Permanent CORS and RTK reference stations
• Survey-control and construction reference networks
• Landslide, slope and debris-flow monitoring
• Bridge, dam, building and structural movement monitoring
• GIS positioning and mapping infrastructure
• Long-duration raw GNSS data collection

Who Is the AlphaGeo LR9 For?

The LR9 is intended for survey companies, engineering firms, construction organisations, monitoring specialists, GIS teams and public agencies that need a fixed GNSS receiver rather than a handheld rover. It is particularly suitable when measurements or correction data must remain available around the clock.

For organisations planning a new reference station or monitoring installation, Global GPS Systems can help assess the required antenna, power supply, communications, mounting hardware and compatible field receivers. Correct system design is important because the final performance of a permanent GNSS station also depends on antenna placement, site stability, satellite visibility and network configuration.