European Space Agency

Objectives

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

Challenges

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)

Benefits

  • 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

Features

  • 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

Plan

Milestones:

  • 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