Secure Position Augmentation for Real Time Navigation

The SPARTN format is an industry-driven standard for communication of GNSS high accuracy correction data between service providers and end users

Global Navigation Satellite Systems (GNSS) are satellite-based positioning systems that are currently providing global service 24 hours each day. Systems within GNSS include the Global Positioning System (GPS), the Global Navigation Satellite System (GLONASS), Galileo Satellite System, the Quasi-Zenith Satellite System (QZSS), and the Beidou Navigation Satellite System (BDS). Many types of correction services exist to improve the accuracy of these systems. Among these are techniques that emerged from precise positioning approaches that do not require that the end user also set up some reference GNSS station or network. These positioning systems rely on service providers to gather and process information from numerous real-time sources and then broadcast the resulting correction data to the end user. The correction data is then used with the GNSS receiver measurements to allow accurate positioning/navigation with high reliability.

Until SPARTN there has not been an industry recognized standard that supports wide and global area broadcasts and other performance requirements. Modern positioning systems require a combination of low bandwidth, accuracy, availability, reliability, and integrity for safety of life applications. The SPARTN message format has been developed meeting these requirements. As a result, the SPARTN message format is an evolution of other legacy state space representation (SSR) formats that have been made available by different players in the GNSS industry. This evolution combines the advantages of state representation with state-of-art communication protocol fundamentals for GNSS corrections.


The SPARTN format was originally concepted under the name SAPA by Sapcorda Services in collaboration with member companies of the Sapcorda joint venture. Over time the format design evolved based upon collaboration and interoperability testing with other key companies in the industry.

Versions development and Roadmap

1.1Initial release of Orbit/Clock/Bias for GPS and GLONASSMarch 2019Deprecated
1.6.2High Precision Atmosphere Correction (HPAC) Messages
Area Definitions
June 2019Deprecated
1.8Encryption/Decryption of Messages
Definition of Dynamic Key Messages
Message Authentication Definition
Basic Precision Atmosphere Correction (BPAC) Messages
December 2019Deprecated
2.0Support to Galiileo, BeiDou, and QZSS
Support to proprietary messages
Redefinition of the standard name with “Secure” replacing “Safe”
June 2021Deprecated
2.0.1Added note to indicate minimum implementation of the SPARTN format in section 6
Other minor editorial changes
September 2021Deprecated
2.02Extended BDS signal types for code and phase biases with BeiDou 3 signalsFebruary 2022Current version available through link below

The SPARTN format is available to anyone
for download and distribution free of charge.

Reference material

Publications about SPARTN

Publications referring to SPARTN

Companies/Organizations supporting SPARTN

  • Bosch
  • Geo++
  • Mitsubishi Electric
  • Sapcorda Services
  • Septentrio
  • u-blox