European Space Agency

NavSW4NewSpace - GNSS Software Port to New space Hardware


The activity addresses the porting of the existing GNSS Software to a COTS based hardware that can be used

  • for a stand-alone GNSS receiver
  • as a slide-in module in the COTS version of the On-Board Computer from RUAG Sweden


Adaption of RUAG’s existing Navigation Software for Hi-Rel space receivers to the following new constraints:

  • New baseband processor performing autonomous acquisition and tracking of GNSS satellites as commanded by the NavSW
  • New hypervisor environment
  • New processor architecture
  • Changed real-time constraints (from an interrupt-driven execution model to an event-driven execution model)


  • High level of integration of GNSS receiver into On-Board computer or stand-alone GNSS receiver
  • Excellent positioning accuracy
  • Optimal utilization of hardware resources
  • Low cost
  • Low power consumption
  • Low mass
  • Small size
  • Quick production and delivery


  • Acquisition and tracking is performed in hardware (FPGA)
  • Processor sharing with On-Board computer possible
  • No extra power supply
  • GNSS SW capable of processing measurements on the following signals:
    • GPS C/A on L1
    • Galileo E1 B/C
  • Computation of an accurate navigation solution, either a
    • Kinematic (unfiltered) Least squares solution or
    • Dynamic Kalman-filtered solution
  • Optimized footprint and estimated power consumption <7W

System Architecture

The electronics COTS board is an ongoing development by RUAG Sweden featuring a PowerPC for SW execution (possibly shared with the On-Board computer), a FPGA for autonomous acquisition and tracking. Code and carrier phase measurements are computed within the FPGA and are passed to the navigation SW for computation of the navigation solution



  • Requirements Review
  • Software PDR / Final Review

Current status

Activities in progress:

  • Requirements Engineering
  • SW Design
  • Adaption of simulation environment and test systems
  • Setup of development enviroment

Upcoming activities:

  • SW Implementation and Integration

Status date

Wednesday, June 12, 2019 - 11:46