Design and Experimental Validation of an Embedded Firmware Architecture for an SDR CubeSat Payload

Abstract

This paper presents the design, implementation, and experimental validation of an embedded firmware architecture for a Software-Defined Radio (SDR) payload intended for CubeSat applications. The proposed solution targets the space-oriented Totem SDR board, which is based on the Xilinx Zynq-7020 System-on-Chip. Unlike conventional Linux deployments on Zynq platforms, the proposed architecture is developed with consideration for CubeSat constraints, including compact on-board integration, reliable firmware deployment, and lightweight subsystem communication. The development workflow combines the Xilinx Vivado toolchain for hardware configuration and boot component generation with Buildroot for the creation of a customized embedded Linux distribution. A structured loading procedure was implemented to deploy the boot image, kernel, device tree, and root file system onto the SDR board through the JTAG interface. To validate the correct operation of the embedded system, the CubeSat Space Protocol (CSP) was integrated through a cross-compilation process and tested over a CAN interface between a host computer and the SDR platform. The obtained results confirm the successful deployment of the firmware and demonstrate the suitability of the proposed architecture as a flexible and reliable embedded solution for future CubeSat SDR missions.