Impact of Noise Figure on a Satellite Link Performance

Small satellite link performance analysis is critical for assessing the adequacy of a transmitter to successfully transfer data at the desired rate. This is especially obvious when considering highly adaptive small satellite systems that exhibit static and active/dynamic power requirements. This paper presents the impact of noise figure on the carrier and data links performances of a highly adaptive small satellite application. The noise figures of a MMIC LNA, designed using GaAs technology operating within the C- and X-bands, were used to study the link performance of a planetary mission. An existing Magellan spacecraft link performance was considered in this study. The analysis reveals that designing a broadband LNA to have a ripple of less than 0.1 dB within its operating bandwidth is essential for a less than 2 dB drop in the carrier and data links margins. This fixes a 6.8 K receiver noise temperature swing margin for reliable, dynamic, broadband and adaptive space operations.