Analysis Examples
Provided below are some examples of the analysis RASL offers its clients. For more information please get in touch, RASL will be happy to provide an overview of the services offered and example outputs free of charge
Shielding Analysis
RASL can perform shielding analysis for EEE parts and materials using ray-tracing, Reverse Monte Carlo and Forward Monte Carlo methods. The example below is for a simple ray-tracing analysis of a component mounted to a PCB with an Aluminium frame around (other structures have been removed for clarity). The die of the component housed within the part packaging can be seen in the upper left image. The ray-tracing results are shown in the top right image for a partial range of shielding thicknesses. The bottom image presents the results using a box mapping around the component.
« FASTRAD® »
« FASTRAD® »
« FASTRAD® »
Total Ionising Dose (TID) Depth Curves
An example of the output from an analysis of the total ionising dose levels for three different orbit types - GEO, 800km sun-synchronous LEO and the ISS.
A hypothetical tolerance has been indicated which could represent a component, equipment or material. The variation in the curve shapes are due to different contributions of trapped electrons, trapped protons, solar protons and secondary particles which all contribute to TID.
Depth curves can also be generated for Total Non-Ionising Dose (TNID - also known as displacement damage) and internal charging.
Radiation Environment Risk Mapping
In LEO there exists a heightened radiation environment area known as the South Atlantic Anomaly (SAA). This contributes significantly to the TID and TNID dose levels and also the risk of SEE. The reason for this area of increased trapped proton flux is the rotational and magnetic axes of the Earth being non-concentric.
It is important to understand the risk posed to missions and mapping the region aids in this. The risk varies with mission orbital altitude and inclination.
Similar plots can also be created for trapped Electrons, Solar Protons, Galactic Cosmic Rays (GCR), etc.
« OMERE® »
Single Event Effect (SEE) Analysis
SEE are typically calculated and presented as rates, such as SEU/bit/day or SEL/device/day. They may also be presented in terms of a number per mission or a MTBE (mean time before event). For all mission types the rate for the background environment and the heightened solar flare environment need to be assessed.
For space environments the two main causes of SEE are heavy ions (GCR, solar flares) and protons (trapped, solar flares). For LEO orbits in particular (due to trapped protons in the SAA) the risk of SEE varies with orbital position. The examples below (2D and 3D) are outputs of an analysis into the orbital variation in SEE rates due to protons. The peaks over the poles are due to solar flare protons
This type of analysis can aid in the assessment of the SEE impacts to the mission.
« OMERE® »
« OMERE® »
Particle Physics
An understanding of how particles such as protons and heavy ions interact with matter is very important for aspects such as radiation testing, SEE analysis and radiation shielding.
Below are some example outputs from a Monte Carlo analysis of how Xenon Ions generated at a test facility (E=1217MeV) interact with Silicon. The range of the ions in Si is ~90microns, a clear indication that de-lidding of components is required for device Heavy Ion testing. Remember - heavy ions in space have much higher energies!
