1. Fraunhofer Onboard Radiation Sensors (FORS)
Stefan Metzger, Stefan Höffgen, Christoph Komrowski, Jochen Kuhnhenn, Michael Steffens, Tobias Kündgen

2. Outline Fraunhofer Onboard Radiation Sensors
Implementation on Fraunhofer On-Board Processor on Heinrich-Hertz-Satellite
UV EPROM for Measuring Total Ionising Dose
SRAM for Detecting Solar Particle Events
Facts and Figures at a Glance
The Fraunhofer-Gesellschaft undertakes applied research of direct utility to private and public enterprise and of wide benefit to society.
Industry
Service sector
Public administration
Fraunhofer-Gesellschaft, the largest organization for applied research in Europe
At present, the Fraunhofer-Gesellschaft maintains 67 institutes and research units.
The majority of more than 22,000 staff are qualified scientists and engineers
€1.9 billion annual research budget totaling. Of this sum, €1.6 billion is generated through contract research. More than 70 percent of the Fraunhofer-Gesellschaft’s contract research revenue is derived from contracts with industry and from publicly financed research projects. Almost 30 percent is contributed by the German federal and Länder governments in the form of base funding.
Research centers and representative offices in Europe, USA, Asia.

3. Outline Fraunhofer Onboard Radiation Sensors
Implementation on Fraunhofer On-Board Processor on Heinrich-Hertz-Satellite
UV EPROM for Measuring Total Ionising Dose
SRAM for Detecting Solar Particle Events
Facts and Figures at a Glance
The Fraunhofer-Gesellschaft undertakes applied research of direct utility to private and public enterprise and of wide benefit to society.
Industry
Service sector
Public administration
Fraunhofer-Gesellschaft, the largest organization for applied research in Europe
At present, the Fraunhofer-Gesellschaft maintains 67 institutes and research units.
The majority of more than 22,000 staff are qualified scientists and engineers
€1.9 billion annual research budget totaling. Of this sum, €1.6 billion is generated through contract research. More than 70 percent of the Fraunhofer-Gesellschaft’s contract research revenue is derived from contracts with industry and from publicly financed research projects. Almost 30 percent is contributed by the German federal and Länder governments in the form of base funding.
Research centers and representative offices in Europe, USA, Asia.

4. Onboard Radiation Sensors Goals
Characterize the radiation environment in terms of dose and particle flux.
Design and build radiation sensors that are
simple,
robust,
cheap and
easy to integrate.
Measure radiation where you really need it
locally on printed circuits boards,
inside electronic boxes and/or
in close proximity to radiation sensitive devices.
Support anomaly investigation.
Enable mitigation of radiation effects.

5. Onboard Radiation Sensors Approach
Do not install a separate radiation sensing systems.
Implement as few as possible additional devices that are
easy to operate,
consume low power and
do not put the whole system at risk.
Stay fully digital so that no complex data processing is needed.
Use already installed flight hardware, i.e. processor, interfaces, transceivers etc. for operation and communication, whenever possible.

6. Fraunhofer Onboard Radiation Sensors Solution
Calibrate memory devices under radiation so that altered bits represent received ionising dose or particle flux.
Integrate e.g. 2 memories on processor boards for TID and SPE each.
Devices will be operated by system processor.
Measurement results will be send to ground via main transmitters.
Processor unit
Receiver
Interface
Memory
Transmitter
Flash
SRAM
SRAM SEU Monitor
UV EPROM TID Meter
Already existing hardware
Additional memory devices

7. Outline Fraunhofer Onboard Radiation Sensors
Implementation on Fraunhofer On-Board Processor on Heinrich-Hertz-Satellite
UV EPROM for Measuring Total Ionising Dose
SRAM for Detecting Solar Particle Events
Facts and Figures at a Glance
The Fraunhofer-Gesellschaft undertakes applied research of direct utility to private and public enterprise and of wide benefit to society.
Industry
Service sector
Public administration
Fraunhofer-Gesellschaft, the largest organization for applied research in Europe
At present, the Fraunhofer-Gesellschaft maintains 67 institutes and research units.
The majority of more than 22,000 staff are qualified scientists and engineers
€1.9 billion annual research budget totaling. Of this sum, €1.6 billion is generated through contract research. More than 70 percent of the Fraunhofer-Gesellschaft’s contract research revenue is derived from contracts with industry and from publicly financed research projects. Almost 30 percent is contributed by the German federal and Länder governments in the form of base funding.
Research centers and representative offices in Europe, USA, Asia.

8. Fraunhofer Onboard Radiation Sensors Heinrich-Hertz-Satellite
Source: OHB
DLR Space Administration wanted to develop and operate a German communication satellite.
Build on SmallGeo platform from OHB.
To be launched in 2020.
The main objective of the mission is the scientific validation and testing of payload technologies in space.
Unfortunately no radiation sensor is foreseen.
Fraunhofer IIS is provider of one of the scientific communication payloads.
The Fraunhofer On-Board Processor (FOBP) is a powerful and flexible programmable comm payload.
The FOBP consists of radiation-hardened FPGAs that can be fully reconfigured in orbit.
On the FOBP in-orbit verification of radiation sensors is added.

9. Fraunhofer Onboard Radiation Sensors Fraunhofer On-Board Processor Concept
Source: Fraunhofer IIS

10. Fraunhofer Onboard Radiation Sensors Actual Design for Heinrich-Hertz-Satellite
© Fraunhofer IIS
© Fraunhofer IIS

11. Outline Fraunhofer Onboard Radiation Sensors
Implementation on Fraunhofer On-Board Processor on Heinrich-Hertz-Satellite
UV EPROM for Measuring Total Ionising Dose
SRAM for Detecting Solar Particle Events
Facts and Figures at a Glance
The Fraunhofer-Gesellschaft undertakes applied research of direct utility to private and public enterprise and of wide benefit to society.
Industry
Service sector
Public administration
Fraunhofer-Gesellschaft, the largest organization for applied research in Europe
At present, the Fraunhofer-Gesellschaft maintains 67 institutes and research units.
The majority of more than 22,000 staff are qualified scientists and engineers
€1.9 billion annual research budget totaling. Of this sum, €1.6 billion is generated through contract research. More than 70 percent of the Fraunhofer-Gesellschaft’s contract research revenue is derived from contracts with industry and from publicly financed research projects. Almost 30 percent is contributed by the German federal and Länder governments in the form of base funding.
Research centers and representative offices in Europe, USA, Asia.

12. FORS: TID TID Dosimetry with EPROMs
Proposed device:
8 Mbit M72C F6 UV EPROM by STMicroelectronics
To change a '0' to a '1' (erasure) is typically done by die exposure to ultraviolet light
TID effects in EPROMs:
Holes in isolator combine with electrons in the floating gate which leads to bit flips.
The number of '1' is a measure of the TID.
Pros of non-volatile memories:
Integrating dose meter
Can be switched-off most of the time
Save energy
Latch-up free

13. FORS: TID TID Calibration at INT Co-60 Gamma Source
Measurements of dependencies during irradiation
Device-to-device
Dose-rate
Temperature
Voltages (programming, read, write)
Reproducibility
45.4 krad/hr
0.4 krad/hr
Based on GERD for H2Sat behind 7 mm Al: 21 krad (Si)

14. Outline Fraunhofer Onboard Radiation Sensors
Implementation on Fraunhofer On-Board Processor on Heinrich-Hertz-Satellite
UV EPROM for Measuring Total Ionising Dose
SRAM for Detecting Solar Particle Events
Facts and Figures at a Glance
The Fraunhofer-Gesellschaft undertakes applied research of direct utility to private and public enterprise and of wide benefit to society.
Industry
Service sector
Public administration
Fraunhofer-Gesellschaft, the largest organization for applied research in Europe
At present, the Fraunhofer-Gesellschaft maintains 67 institutes and research units.
The majority of more than 22,000 staff are qualified scientists and engineers
€1.9 billion annual research budget totaling. Of this sum, €1.6 billion is generated through contract research. More than 70 percent of the Fraunhofer-Gesellschaft’s contract research revenue is derived from contracts with industry and from publicly financed research projects. Almost 30 percent is contributed by the German federal and Länder governments in the form of base funding.
Research centers and representative offices in Europe, USA, Asia.

15. FORS: SPE Single Event Upsets (SEU) in SRAMs
PMOS
NMOS On
Off 1
Data
Sensitive pn-junctions
Vss
VDD
Main source of SEUs in GEO:
Solar Particle Events (SPE)
Galactic Cosmic Rays (GCR)
N Substrate
VDD n+
Depletion zone
P well p+
VSS
Vout 1 on
off
High energy particle + -
Vin

16. FORS: SPE The ESA SEU Monitor
Device Proposed:
Atmel 4 MBit SRAM AT VYC respectively
Part of ESA SEU Monitor
No degradation up to at least 120 krad(Si)
No SEL up to 106 MeV cm²/mg
Flies aboard ESA Proba-2 mission
Calibration data available from:
PIF, KVI (Protons)
HIF, RADEF (Protons, HI)
TAMU (HI)
GSI (HI)

17. FORS: SPE The ESA SEU Monitor: Calibration
Rough first estimates based on GERD for H2Sat:
Quiet condition about 0.1 SEU/day
Large SPE several hundred SEU
Heavy ion calibration
Proton calibration
Ref.: IEEE TNS, VOL. 55, NO. 6, DEC. 2008, pp3082.

18. Thank you for your attention!
Dr. Stefan Metzger
Deputy Director
Head of Department NE