Recent On-Orbit Results and ARQ Performance Analysis for the TBIRD 200-Gbps Mission
Curt Schieler, Bryan Bilyeu, Jesse Chang, Ajay S. Garg, A. Horváth, Kathleen Riesing, Bryan S. Robinson, Jade P. Wang, Sabino Piazzolla, Beth Keer
Abstract
The TeraByte Infrared Delivery (TBIRD) mission has successfully demonstrated 200-Gbps laser communication downlinks from a 6U CubeSat in low-Earth orbit (LEO) and has delivered up to 4.8 terabytes (TB) error-free in a 5-minute pass. In total, 65 passes have been performed since launch in May 2022, with 22 of those passes conducted in April-May 2023. The TBIRD space and ground terminals leverage commercial fiber-coupled coherent transceivers along with a custom Automatic Repeat reQuest (ARQ) protocol to ensure error-free communication through the atmospheric fading channel. This paper presents data throughput results from the on-orbit passes and an analysis of the ARQ system operation that shows that near-optimal performance was achieved. Results from Doppler compensation experiments that increased the data volume per pass are also presented.