Link-Budget Analysis of Dynamic Impairments on E-/W-Band High Through-Put Feeder Links for Future VLEO Small Satellites

Very low earth orbit (VLEO) presents unique challenges for satellite-to-ground communication because of higher orbital velocity, reduced contact times, and rapidly changing link geometry. However, VLEO offers advantages such as reduced latency, improved spatial resolution, and enhanced link margins for small satellites and earth observation. Maximizing transmitted data during each shortened overpass in VLEO using available bandwidth in millimeter-wave (mmW) frequency bands, especially the E-/W-band (71-76 GHz and 81-86 GHz), becomes important. This link budget analysis focuses on rapidly changing link parameters and their effects on communication link quality.
Link budgets are calculated over time for a satellite zenith pass in a circular orbit at altitudes between 150 km and 500 km. The calculations use all available ITU models for atmospheric effects, and the communication systems, including transmitter, receiver, and antennas, are modeled as parameterized entities. Performance is based on the achievable system gain of state-of-the-art transceiver technology in small satellites to estimate link quality and capacity. Calculations for a realistic scenario show the feasibility of multi-Gbit/s VLEO-to-ground communication with a compact 1.2 m receive antenna and availability above 99% in E-/W-Band.
The results show that robust mmW communication links in E-/W-band for VLEO small satellites are achievable with current technologies but require detailed analysis of dynamic link conditions, adaptation to the unique orbital environment, and consideration of operational constraints. The link budget framework and results are intended to support early-phase mission design and trade-off studies for future VLEO small satellite missions and to contribute to the expanding body of work on long-term operational use of VLEO.