The IDRS concept brings the capabilities of the Inmarsat BGAN system to space by integrating the IDRS terminal into a LEO spacecraft. While in orbit, the IDRS link to the Inmarsat BGAN Ground Network is maintained via the global constellation of the INMARSAT 4 GEO satellites. Building upon INMARSAT-4 constellation and its BGAN ground infrastructure, both GLOBAL coverage and Global connectivity are being achieved. Leveraging on the BGAN service portfolio, this provides a range of always-on, on-demand, real time connectivity, thus resolving the need to wait for the LEO satellite to pass above a ground station!

At the same time, it supports the following IP services:
• Background IP
• Streaming IP and
• Assured IP

System Concept Diagram

Service coverage map at 500 km altitude (2017)

System Information:

Addvalue IDRS POC Terminal is a CubeSat two unit form factor with the following:

Cubesat 2U Form Factor
  • Two independent BGAN transceivers for redundancy
  • Built in GPS Receiver
  • Approximate weight is 2.3kg
  • Peak power: 22W
  • Typical operation power 10W (use cases in Telemetry, Tracking and Command, Tasking)
  • Dimension is 96 x 89 220 mm (L x W x H)
IDRS i100 Transceiver

The Addvalue IDRS terminal is a good fit for LEO satellites of all sizes, down to the “New Space” Nano-satellites.

Service Capabilities – Connection characteristics:

  • Support uninterrupted, seamless IP session during rapid spot beam handovers
    • Spot-beam handover frequency is every 2 to 3 minutes
    • IP session is NOT interrupted during spot beam handovers
  • Low latency of between 0.5 to 1.5 seconds
  • Short interruption only in satellite to satellite handovers (order of 20 seconds)
    • Re-acquisition / registration (to BGAN network) may take a few seconds
    • Assumes a fixed antenna, i.e., no re-pointing time
  • High network availability (>99.5%) as well as high link availability (<99%) and reliability provided by Inmarsat BGAN communications network
  • Coverage may varies with LEO orbital altitude and inclination
    • Typical Forward link (16 QAM) is between 200 to 300kbps and Return link (QPSK) is between 96 to 250kbps)
IDRS™ payload in vacuum chamber, simulating space environment