Available at: https://digitalcommons.calpoly.edu/theses/3093
Date of Award
6-2025
Degree Name
MS in Electrical Engineering
Department/Program
Electrical Engineering
College
College of Engineering
Advisor
Andrew Danowitz
Advisor Department
Electrical Engineering
Advisor College
College of Engineering
Abstract
CubeSats represent a rapidly evolving platform for space research, industry, and education, demanding increasingly sophisticated onboard computing solutions that balance performance, fault tolerance, size, weight, and power constraints. Although the design of the Cal Poly's CubeSat Lab's (PolySat) current On-Board Computer (OBC) keeps up with many of these factors, the demands of modern workloads like fine attitude determination will start to outpace available compute. While the selection of a more capable processor to address this would have traditionally resulted in increased energy usage, modern system-on-chip (SoC) architectures offer novel ways to trade available compute for power savings on-the-fly. With this motivation, the NXP i.MX7ULP SoC—a dual-core heterogeneous architecture featuring an ARM Cortex-A7 and Cortex-M4—is investigated for use in PolySat’s next-generation OBC. A performance and power trade study is conducted using an i.MX7ULP development kit, focusing on critical capabilities such as fault tolerance, power modes, cross-core communication, floating point arithmetic, and vectorization. The A7 and M4 cores are also individually characterized and assessed for software development ease. Results indicate that performance of this SoC can scale up to 15x that of the existing OBC while still being more energy efficient. They also showed the M4 core has the potential of reducing idle state power consumption by up to 53% of the current OBC's by power-gating the other core. Additionally, worst case power consumption during intensive tasks remained under 480 mW. Cross-core communication overhead was also shown to be minimal and software development was found to be approachable using available software development kits (SDKs). The results of the investigation were applied towards starting the design of a software and hardware architecture that poises PolySat to handle the missions of today and the future.