1U satellite

The 1U can be configured to have a quality camera that can be pointed quickly, accurately and reliably to take photos of Earth or into space. In order to give a good real-time user experience Space Inventor provides the opportunity to add a  high speed link via S-band or X-band allowing photos to be downloaded in a few seconds which results in an “point and shoot”-like capability.

All Space Inventor satellite platforms have a design lifetime of 5 years.

Applications of Space Inventor’s satellite platform:

  • Educational missions
  • BIU missions
  • In-orbit demonstration missions
  • Scientific missions
  • IoT missions
Payload mass
> 0.3 kg
Payload Volume
0.2 - 0.5 unit
Payload power
7 W
1 degree
Data downlink
2x S/X band 4 - 200 Mbps
Flight Heritage

Subsystems in Space Inventor’s 1U satellite


The satellite platform is designed by using the high reliable subsystems made by Space Inventor providing high performance, low EMI and very easy integration. The basic avionics consists of four basic elements:

  • The power plant for power generation, conditioning and distribution
  • on-board data handling
  • Communication to ground segment
  • attitude determination and control system

The satellite platform is designed with reliability and performance as the primary design drivers. It uses the shielded hi-rel subsystems: Batteries, power conditioning and distribution, communication and attitude control. Each system has its own radiation shielding, EMI shielding, thermal conduction path, and mechanical support. The satellite is designed not only for extreme ruggedness but also ease of integration. Any side panel can easily be removed and are then free with no cables attached.

Power plant


The complete Space Inventor power systems suite consisting of the MPPT-P3, BAT-P3, PCDU-P3 is providing an agile and effective solution. The power systems provide all functionalities needed from maximizing power input from the photovoltaic cells, storing power and providing regulated output channels to individual subsystems and on the output side an unregulated V-bat is also available.

  • 12 power output channels with protection and monitoring
  • Power metering, latch-up protection, battery discharge management and protection, programmable on/off timers
  • Maximum power point tracker for satellite solar panels
  • Integrated battery change management
  • 8 LiIon cells configurable for 14.4 or 28.8V at 92 Whr
  • 2 double-deployable solar panels: 12 W peak power

Attitude Determination and Control System


Space Inventor’s attitude and orbit determination and control solutions are comprised by our wide range of high-performance, rugged and modular AOCS avionics products. The range of modules spans from very small cubesat reaction wheels to large reaction wheels for satellites up to several hundred kilograms. Furthermore, we manufacture a best-in-class star tracker, integrated fine sun sensors, magnetorquers, GPS modules, ADCS computers and software which we use to configure tailored ADCS and AOCS solutions for both simple cubesats and highly advanced science satellites.


ADCS features: 

  • Includes fully featured ADCS software
  • Pointing modes include: Nadir, sun tracking, ground spot tracking, inertial pointing, dual target (e.g. nadir while sun tracking)
  • Actuators: 4 reaction wheels, redundant magnetorquer rods
  • Sensors: 5 fine sun sensors, 5 gyroscopes, 5 magnetometers
  • Performance: 1 degree pointing accuracy
  • The software runs on the redundant OBC-P3

Momentum Wheel


Space Inventor’s 1U satellite uses a fully integrated reaction wheel unit for high performance satellite attitude control with mission lifetime of 5 years (minimum). The WHL-10 wheel is an integrated 3-phase outrunner Permanent magnet synchronous motor (PMSM) with 8 rare-earth magnet poles in the rotor and 6 teeth in the stator. Material for the body is Al-7075-T6, rotor is made of ferritic stainless steel while the magnets are Neodymium.

The rotor is axially suspended between two hybrid ceramic high precision bearings chosen for long life and low friction in vacuum conditions. The wheel is commutated by its own internal microcontroller, which runs the control loop to control speed and acceleration upon commands from the ADCS computer.




  • Compact, integrated reaction wheel unit for 1-3 kg CubeSats
  • Momentum storage of 10 mNms @ 20.000 RPM
  • Torque 2 mNm
  • Control: Momentum, torque, speed or motor voltage
  • 3-phase Permanent magnet synchronous motor (PMSM)
  • Can bus interface with CSP
  • Rotor inertia: 5 x 10-6 kg mm2
  • Measurements: 30 x 30 x 21 mm // 59 g



The highly integrated Fine Sun Sensor (FSS-1G2), integrated in an advanced 1U satellite, uses four photodiodes to estimate the sun direction vector with a precision of 1 degree. The module has a built-in micro controller which enables connectivity to a CSP network via CAN bus and readily integrate with an attitude determination and control system such as e.g. ADCS-P3 and ADCS-R3. In addition to the sun sensor functionality, the module includes a 2-axis gyroscope and 3-axis magnetometer making it a versatile attitude sensing component. The 1G2 variant is an upgraded version of the previous 1G model which has flight heritage. 1G2 is expected to be launched in Q1 2022.



  • 2-axis sun direction sensor based on quad photo diode array
  • 1 degree precision
  • 55 degree half-cone FoV
  • Integrated 3-axis magnetometer
  • 0.25mG per LSB resolution
  • 0.4mG total RMS noise
  • Magnetic field direction accuracy 1º
  • Integrated 2-axis Gyro
  • Ultralow noise: 0.004°/s/√Hz
  • 5-28V unregulated power input
  • Data interface: CAN bus with CSP2.0
  • Measurements (L, W, H): 40x20x10 mm



The communication system consists of a VHF/UHF TT&C radio for telemetry and commanding the spacecraft. The radio system can be configured to different operating frequencies according to the frequency license obtained from ITU for space operation. A high data-rate radio in S-band (STTC-P3) can also be included in the configuration with a patch antenna mounted on face pointing Nadir.

  • UHF/VHF radio (TTC-P3)
  • UHF/VHF antenna (DMA)
  • S and X-band transmitter (STTC-P3)


The TTC-P3 is a hot-redundant satellite telemetry, tracking and command (TT&C) radio with two half-duplex VHF/UHF transceiver designed to enable robust and reliable satellite communication. The TTC-P3 is intended to be used in an antenna diversity scheme, where each channel is connected to orthogonal and cross-polarized antennas. Hereby a good omnidirectional gain pattern can be achieved, which makes signal reception nearly independent of satellite attitude.

Careful receiver design provides a noise figure below 2 dB, which, combined with concatenated convolutional and Reed-Solomon decoding, ensure excellent sensitivity. Realizing that interference have proved problematic over certain regions, the TTC-P3 also features a 60 dB out-of-band rejection filter.



The features


  • 2 Half-Duplex VHF/UHF Transceivers
  • Data-rate: 4800 – 38400 kbps nominal (up to 115.200 available upon request)
  • Frequency bands: 130-140,140-150, 400-410 and/or 430-440 MHz
  • 30 dBm output power at > 50% PA efficiency
  • Noise Figure: <2 dB
  • Modulation: GMSK
  • FEC: Convolutional Coding (K=7, r=½) and Reed Solomon (RS-223,255)
  • Measurements: (L, W, H) 91.14 x 94 x 11 mm // 143 g


The STTCX-P3 is a software defined satellite transceiver offering a versatile S/X-band transceiver module for high-speed communication and ranging solution for both LEO and GEO missions. The transceiver is designed to work with the latest CCSDS Cat A recommendations for high data rate transmissions and high spectral efficiency. Using constant envelope GMSK or low crest factor SRRC filtered OQPSK modulation for higher power amplifier efficiency and lower linearity requirements.

The ranging functionality supported is transparent pseudo noise ranging according to CCSDS 414.0-G2 standard where the transceiver frequency-translates the uplink ranging signal to the downlink without code acquisition (i.e., non-regenerative ranging or turnaround ranging) – Eventually active regenerative ranging system will be supported The SDR is based on a powerful Xilinx Zync-7030 SoC and high-performance Analog Devices SDR front-end, the AD9361.



  • Channels: 2 receive, 2 transmit
  • 2 x S-band uplink : 2025 – 2110 MHz
  • 1 x S-band downlink: 2200 – 2290 MHz
  • 1 x X-band downlink: 8025 – 8400 MHz
  • Tx power up to 2 Watt
  • Rx noise figure: 5 dB (TBD)
  • Full duplex
  • Tx amplifier bypass function
  • CCSDS compliant (401.0-B-30)
  • GMSK or OQPSK – 9600 bps to 20 Mbps
  • FEC: Convolutional Coding (K=7, r=1⁄2) and Reed Solomon (RS-223,255)
  • CCSDS Scrambling
  • Modem fully implemented in FPGA with DMA
  • CSP 1.0 and 2.0 protocol
  • 64 GB storage
  • CCSDS compliant (414.0-G-2
  • Transparent PN ranging
  • High-reliability Harwin M80 connector for power and data interface
  • CAN bus
  • LVDS, SpaceWire, RS-422, RS-485
  • Ethernet
  • 4 x 50 Ω RF connectors
  • Thermal heat sinking by flush-mounted PCB on 2.5mm Al
  • Radiation total dose tested EEE parts
  • PC-104 compatible mounting holes
  • Radiation total dose tested EEE parts