A Review of in-orbit Observations of Radiation- Induced Effects in Commercial Memories onboard Alsat-1

This paper presents a review of an 8-year study on radiation effects in commercial memory devices operating within the main on-board computer system OBC386 of the Algerian microsatellite Alsat-1. A statistical analysis of single-event upset (SEU) and multiple-bit upset (MBU) activity in these commercial memories shows that the typical SEU rate at alsat-1's orbit is 4.04 × 10-7 SEU/bit/day, where 98.6% of these SEUs cause single-bit errors, 1.22% cause double-byte errors, and the remaining SEUs result in multiple-bit and severe errors.

• Y. Bentoutou
• A.M. Si Mohammed

• Radiation effects
• error detection and correction
• satellite computer
• small satellite mission.

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