The SparkFun RTK Reference Station – News

A LATE Thursday post about our newest RTK Surveying tool that is now available!




It should come as no surprise that we love surveying tools and we put a lot of pride and effort into those we create here at SparkFun Electronics. Because of all of you who use our RTK Surveyors, Expresses, or Facets, we’ve been shown a direction and drive to create more options for you to use. Today, we announce our newest product to join this line based on your feedback. Meet the SparkFun RTK Reference Station!

The SparkFun RTK Reference Station is the perfect solution for your high-precision geolocation, surveying, and time reference needs. For basic users, it is incredibly easy to set up a fixed location NTRIP server, enabling RTK for rovers and even as an NTP server for equipment synchronization and an astoundingly accurate time base.

RTK is short for Real Time Kinematics. A satellite positioning receiver capable of RTK takes in the normal signals from the Global Navigation Satellite Systems (GNSS) along with a correction data stream to achieve improved positional accuracy. GNSS includes satellites from GPS (USA), GLONASS (Russia), Beidou (China), Galileo (Europe), plus special additional satellites (e.g., SBAS and QZSS). On their own, these signals will deliver ~30cm positional accuracy. An RTK receiver takes in an additional Real Time Correction Message (RTCM) data stream and then calculates the device’s location with 1cm accuracy in real-time. RTK works best when the correction data is generated locally; the ‘Rover’ receiver accuracy degrades as the distance (baseline) between it and the ‘Base’ generating the corrections increases. With just a few minutes of setup, the SparkFun Reference Station allows you to generate that correction data locally and share it via Ethernet!

Internal circuitry of the RTK Reference Station

Under the hood, the Reference Station is based on the ESP32-WROOM processor and u-blox ZED-F9P multi-band GNSS module. It runs the same open-source firmware as our other RTK products. The Reference Station has 10/100 Mbps Ethernet connectivity and it can be powered by Power-over-Ethernet (PoE). The microSD card is connected via a 4-bit SDIO interface, providing an order of magnitude improvement in read and write speed. Similarly, the u-blox ZED-F9P GNSS module is connected via a high-speed SPI interface, also providing an order of magnitude improvement in the GNSS data transfer speed. Want to log RAWX and SFRBX from all constellations at 20Hz? With this product, you can! We also included an ATECC608A crypto co-processor if you want to write your own firmware and use the Reference Station for crypto mining/space weather station applications or to secure/authenticate your GNSS data.

This device can be used in multiple modes, including:

  • GNSS Base Station with NTRIP – RTCM corrections are sent to a Caster over Ethernet
  • Network Time Protocol (NTP) Server – providing high-accuracy timing data to other machines via an Ethernet network

Those two modes are the ones most users will want to use, but you never cease to amaze us with the variety of ways you use our products. Should you want to, the Reference Station can also be used as:

  • GNSS Positioning Receiver (~30cm accuracy) – also known as ‘Rover’
  • GNSS Positioning with RTK (1.4cm accuracy) – also known as ‘Rover with RTK Fix’ – using NTRIP RTCM correction data over Ethernet or from your phone via Bluetooth
  • GNSS NMEA/UBX TCP Client – sending NMEA and/or UBX navigation data to a remote server using TCP over Ethernet
The RTK Reference Station Yardsale!

The RTK Reference Station comes with everything you need to get up and running. Our kit includes:

  • Cased Reference Station
  • L1/L2/L5 GNSS Surveying Antenna
  • Reinforced RG58 TNC-SMA Cable
  • SMA WiFi / Bluetooth Antenna
  • 32GB microSD Card
  • USB-C Power Supply (wall charger)
  • USB-C Cable
  • Ethernet Cable

What else might you need? Well, it depends on where you are going to install and use your Reference Station. One obvious place would be up on your roof where your antenna will have the best view of the sky. In which case you will want some hardware to help mount the antenna:

Finally, please see the Hookup Guide for more details on which configurations we’ve tried and tested.

And that’s it for today! Make sure to check back tomorrow where Nathan stops by to showcase the kit in a little deeper detail. You could consider the video that we’ve put together as information about the RTK Reference Station straight from the horse’s mouth. Thanks for stopping by and we are extremely excited to see what you make with this new surveyor. We’ll see you tomorrow!