EMLID REACH RS4 Pro

Emlid Reach RS4 Pro is an all-band, multi-frequency RTK GNSS receiver with an integrated dual Full HD camera, designed to take topographic surveying, stakeout, and remote point measurement to the next level in terms of speed, safety, and accuracy. Based on the RS4 platform, it adds augmented reality (AR) and image measurement capabilities, while maintaining the same IP68 ruggedness, up to 16 hours of battery life, and centimeter-level accuracy in all conditions, even under treetops or in urban canyons.

Product Overview

Reach RS4 Pro is an all-band GNSS RTK receiver capable of tracking the main constellations (GPS, GLONASS, Galileo, BeiDou, QZSS, NavIC) on the L1, L2, L5 and L6 bands with 672 dedicated channels, guaranteeing FIX in less than 5 seconds. The advanced GNSS engine, combined with high-performance antennas and advanced management of the L5/L6 bands, ensures stability of the RTK solution even in the presence of multipath, obstacles and noisy signals.

Compared to Reach RS4, the Pro version integrates two factory-calibrated Full HD cameras with global shutter, allowing AR stakeout directly on the real image and the measurement of inaccessible points from photos. This allows you to detect features on facades, infrastructure, or dangerous areas without having to position the pole on site, improving operational safety and productivity in the field.

Usage and applications

Reach RS4 Pro is designed for high-precision topographic surveys, large GIS projects, precision agriculture, and civil engineering applications where speed and visual documentation are critical. The combination of all-band RTK, advanced TILT, and AR allows you to plot points, lines, and complex drawings directly in the field, reducing interpretation errors compared to numerical-only methods.

When combined with Emlid Flow, the system manages AR-guided stakeouts, image acquisition, and classic GIS/construction site workflows, with export to industry-standard formats. RS4 Pro can also operate as an NTRIP rover, RTK base, or integration node for external systems (autopilots, agricultural machinery, GPR, monitoring systems) thanks to radio, LTE, Wi-Fi, Bluetooth, and physical I/O connectivity.

Main technical specifications

Vision and AR

• Image sensors: 1/2.6", CMOS, global shutter, Full HD.

• Field of view:

  • Anterior chamber: H 64.6°, V 42.8°.

  • Lower chamber: H 63°, V 42°.

• Video frame rate: 25 fps.

• Key Features:

  • AR Stakeout with project visualization in augmented reality.

  • Measurement from images for remote or inaccessible points.

GNSS and performance

• Supported bands: L1, L2, L5, L6 (all‑band).

• Constellations: GPS, GLONASS, Galileo, BeiDou, QZSS, NavIC.

• Number of channels: 672.

• FIX time: ~5 s typical in RTK.

• Refresh rate: up to 10Hz.

TILT and sensors

• Tilt compensation: Based on next-generation IMU, with fast initialization and operation without the need for field calibration.

• RTK accuracy with TILT: Accuracy specifications in the order of a few millimeters + ppm (e.g. 7 mm + 1 ppm in horizontal RTK, according to partner reference data).

Mechanics and robustness

• Dimensions: 128.6 × 128.6 × 99.3 mm.

• Weight: approx. 920 g.

• Protection class: IP68, dustproof and waterproof.

• Operating temperatures: −40 °C to +65 °C.

• Structure: Robust body with identical engineering to the RS4 platform, optimised for intensive use on construction sites and agricultural environments.

• Quick release mount: Quick mount for pole with 5/8" thread, compatible with the new Emlid quick-release system.

Power supply and autonomy

• Autonomy: up to 16 hours of continuous work as an RTK rover with active tilt.

• Battery: High-capacity industrial-grade internal battery with optimized power management for extended sessions.

• Charging: via USB Type-C port; compatible with power banks for multi-day use.

Connectivity and data

• LoRa Radio:

  • Frequency: 868/915 MHz (compatible with included 860–930 MHz antenna).

  • Power: up to 0.1–1 W.

  • Range: Up to ~8 km in optimal conditions.

• UHF Radio:

  • Frequency: 410–470 MHz.

  • Power: up to 2W.

  • Protocols: TRIMTALK 450S** support for integration with professional radio bases.

• GNSS/RTK:

  • Fixes: RTCM3 via NTRIP or radio.

  • Modes: RTK rover, RTK base, PPK work.

• Data communications:

  • Multi-band LTE/4G with nano-SIM slot for direct NTRIP connectivity.

  • Wi‑Fi 802.11 a/b/g/n.

  • Bluetooth 5.1 (BR/EDR + BLE) for connection to external controllers and systems.

  • USB Type-C for power and data exchange.

• Logging: Recording of raw data for post-processing (RINEX and other supported formats) to internal memory.

Emlid Reach RS4 Pro Specifications Table

Package Contents

The Emlid Reach RS4 Pro kit comes with a comprehensive package designed to get you started in the field right away, leveraging both GNSS and radio communication capabilities. Included accessories ensure safe transportation, power, and dual LoRa/UHF radio operation without the need for additional components.

The package includes

• Emlid Reach RS4 Pro GNSS receiver.

• Carrying case, designed to protect your receiver and accessories while on the go.

• USB Type-C cable for charging and data connection.

• LoRa 860–930 MHz antenna for use with the integrated LoRa radio.

• UHF 410–470 MHz antenna for the built-in UHF radio.

This configuration makes Reach RS4 Pro immediately operational for RTK surveys, AR stakeouts and remote point acquisition, integrating with the most popular professional topographic and GIS workflows.

The main technical difference is that the RS4 Pro adds a dual Full HD camera system with AR (visual stakeout and image measurement) capabilities and more comprehensive connectivity than the RS4, while the GNSS base, IMU TILT, hardware, and autonomy remain essentially the same. In practice, the RS4 is a “pure GNSS” all-band RTK rover/base, while the RS4 Pro is the advanced version designed for visual workflows, remote points, and complex projects.

Key differences in brief

• Camera system and AR :

  • RS4: No built-in camera.

  • RS4 Pro: Two Full HD cameras with global shutter, AR stakeout and image metering.

• Workflows :

  • RS4: “classic” GNSS surveying and stakeout (coordinates, maps, linework).

  • RS4 Pro: Augmented reality-guided staking, acquisition of inaccessible points from photos, improved visual documentation.

• Connectivity :

  • RS4: LTE, Wi‑Fi, Bluetooth 5.1, LoRa and UHF, already very complete.

  • RS4 Pro: same connectivity base, but optimized for video/photo streaming and AR functions within the Emlid software ecosystem.

GNSS and hardware specifications (almost the same)

RS4 and RS4 Pro share the same all-band GNSS platform with 672 channels, L1/L2/L5/L6 support, and all major constellations (GPS, GLONASS, Galileo, BeiDou, QZSS, NavIC). Both offer FIX in seconds, centimeter-level accuracy, and excellent performance in multipath and under canopy conditions.

IMU and TILT are also common: a new IMU with much faster tilt compensation than the RS3, designed for intuitive working with a tilted pole. Battery life (about 16 hours), a magnesium alloy body, IP68 protection, a weight of around 920 g, and a quick-release mount are shared between the two models.

RS4 vs RS4 Pro Technical Differences Table

In operational summary

• If the focus is classic GNSS survey (construction site, GIS, agriculture) without the need for AR or remote points via image, RS4 already offers the entire next-generation all-band platform.

• If your flow includes Complex stakeout, inaccessible points, lots of visual verification for clients or security , the RS4 Pro justifies the upgrade thanks to dual cameras, AR and photo measurements, while maintaining the same GNSS performance.