OrbFix

Space grade GNSS receivers, with varying degrees of functionality have been available on the micro and small satellite market for several years. The demand for such systems is firstly derived from the most sought application of these satellite classes: precise formation flying and PVT correlated measurements in a spatially distributed network.

Furthermore, the IOD potential of these satellites, makes them the ideal target for experimental missions testing for close orbital maneuvers, for collision avoidance as safety procedures and even for docking. Once demonstrated, these technologies open up new possibilities for deorbiting, in orbit servicing applications, close orbit monitoring and inspection of large targets (i.e. ISS) and even fragmented spacecraft.

OrbFix Prototype

RISE’s solution features a low-cost, COTS-based, Precise Point Positioning, multi-constellation, multi-frequency GNSS receiver for micro and small satellites, allowing ≤10 cm positioning accuracy on a low Earth orbit fully compatible with CubeSat standard. It makes use of trained neural models that can estimate and correct trajectories of spacecrafts, resulting in a more accurate orbit description.

OrbFix during vibration testing campaign

GNSS technology

448 hardware channels for simultaneous tracking of all visible supported satellite signals:

  • GPS: L1C/A, L1C, L1PY, L2C, L2P, L5
  • GLONASS: L1CA, L2CA, L2P, L3CDMA
  • BeiDou: B1l, B1C, B2a, B2I, B3
  • Galileo: E1, E5a, E5b, E5 AltBloc, E6
  • QZSS: L1C/A, L1C, L2C, L5, L6
  • Navic: L5
  • SBAS: Egnos, WAAS, GAGAN, MSAS,
  • SDCM (L1, L5)
  • On module L-band

Protocols

  • NMEA 0183, v2.3, v3.03, v4.0
  • RINEX v2.x, v3.x
  • RTCM v2.x, v3.x (MSN included)

Interfaces

  • UART (LVTTL, up to 4Mbps)
  • SPI
  • I2C
  • CAN
  • Space Wire

RTK Performance

  • Horizontal accuracy 0.6 cm+0.5ppm
  • Vertical accuracy 1 cm + 1 ppm
  • Initialization time 7s

Other positioning modes accuracy

  • Horizontal Vertical
  • Standalone 1.2 m 1.9 m
  • SBAS 1.2 m 1.9 m
  • DGNSS 1.2 m 1.9 m
  • SECORX (PPP) 1.2 m 1.9 m

Velocity accuracy

3 cm/s

Maximum update rate

  • Position 100 Hz
  • Measurements only 100 Hz

Latency

< 10ms

Time to first fix

  • Cold start <45 s
  • Warm start <20 s
  • Re-acquisition 1 s

Package

  • Type: double sided multilayer PCBs
  • Size
  • Weight 40g/1.4 oz

Electrical

  • Antenna pre-amplification range 15-50 dB
  • Antenna bias voltage 3-5.5 V
  • Input voltage 3.3 VDC
  • Power consumption 2W typical, 3W maximum

Environmental

  • Operating temp. -40 to 85 0C
  • Storage temp. -55 to 85 0C

Tracking performance (C/N0 threshold)

  • Tracking 20 dB-Hz
  • Acquisition 33 dB-Hz

Firmware

Free product lifetime upgrades