Calibration of the deposited energy in CMOS imagers for particle detection on nanosatellites

Energy calibration methods are presented that enable COTS-based CMOS imagers to perform radiation monitoring to improve system reliability and extend lifetime. The goal is to reduce extensive beam time with acceptable uncertainties in detection quality

Radiation Monitor Extension for CMOS Imaging Instruments in Nanosatellites

This paper describes a low-cost extension for an imaging observation instrument as a radiation monitor. Adapted image processing methods enable discrimination between measured data and sensor / radiation-specific hazards and drives mitigation techniques to improve mission lifetime

Bad pixel detection for on-board data quality improvement of remote sensing instruments in CubeSats

Large commercial of the shelf pixel arrays in current remote sensing instruments used in CubeSats make on-board processing increasingly important and enables data improvement. Therefore, we first consider the individual steps of the adapted bad pixel detection algorithm - ISMFD. In particular, we consider pixel-to-pixel variations and temporal flickering of pixels in commercial of the shelf sCMOS imaging sensors. We were able to detect an increase of bad pixels from (2.05±0.01)% to (4.1±0.1)% using real measurement images of the flying remote sensing instrument AtmoSHINE. A preliminary implemented adaptive on-board binning method was able to achieve a constant signal-to-noise-ratio on an image with a dynamic light intensity. The additional consideration of bad pixels in the binning method could demonstrate the achievement of data quality of the future remote sensing instrument AtmoLITE

Calibration of the deposited energy in CMOS imagers for particle detection on nanosatellite

Commercial off-the-shelf (COTS) CMOS sensors are increasingly used in scientific applications on nanosatellites. Applying a software-based approach and in addition to their image acquisitions tasks, these CMOS sensors can be used to detect ionizing particles to improve the fault tolerance of imaging instruments on nanosatellites without the need for additional hardware. A challenge in using COTS components for this approach is that essential radiation test data and important parameters such as the thickness of the sensitive epitaxial layer are typically not available. With a simplified calibration approach, we determine the epitaxial layer thickness and calibrate the deposited energy sensitivity with minimal measurement time and steps and minor requirements on the test facility. A forward model for particle track length determination with an increased angle scattering of incident protons is used to handle stronger parameter uncertainties of the test setup. It is shown that the currently used CMOS sensor (HWK1910A) is a suitable candidate for a radiation monitor, based on the determined epitaxial layer thickness and the deposited energy calibration factor, in combination with the in-orbit mission data. This enables capabilities for more individual protection measures in case of unexpected radiation environments

Fault-tolerant modular sensor electronics to perform long‐term measurements with small satellite remote sensing instruments

Single event effects generated by ionizing radiation cause a variety of problems inside satellitesup to mission failures. In case of COTS-based nanosatellites, much effort has to be investedin mitigation measures and redundancy concepts. Increasingly, longer mission durations aretargeted for imaging instruments used as remote sensing devices, e.g., to observe long-termclimate processes. Highly integrated System-on-Module (SoM) architectures enable high processing performance for imaging applications with low resource requirements in terms of powerand mass. The major advantages of these architectures are flexibility, (re)programmability,modularity and module reuse. In order to achieve a fault tolerant design we modeled the radiation environment, estimating the hazards at module level with the objective to reduce therisks to an acceptable level by applying appropriate mitigation techniques. This approach results in an electronics design that combines hardware and software redundancies paired withreconfiguration strategies to assure system availability and reliability for mission lifetime longerthan 3 years in Low-Earth-Orbits (LEO). In this contribution, we will present a dual-imagerelectronics that uses an SRAM-based Xilinx Zynq-7000 architecture, which can accommodatea wide variety of imaging sensors in visible and near infrared spectral range and is part of alimb sounding spatial heterodyne interferometer to measure temperatures in the atmosphere.This instrument is scheduled for the Atmospheric Coupling and Dynamics Explorer (ARCADE)mission inside the International Satellite Program in Research and Education (INSPIRE) seriesof satellites