CubeSat Link Budget: Elements, calculations, and examples

Antenna designs suitable to fly on CubeSats have been of growing interest. The prolific CubeSat antenna literature, however, is contrasted by limited tools for an antenna engineer to develop or understand a CubeSat link budget, which sets the requirements for the spacecraft and ground antenna design. This article presents detailed explanations of the link budget basics, which include not only antenna design terms but also signal processing and system noise parameters. Relations among the data rate, signal-to-noise ratio (SNR), system noise temperature, and antenna gain are reviewed, explained, and applied in three examples of link budgets for CubeSats in low-Earth (LEO), geosynchronous (GEO), and lunar orbits.