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arXiv · 2602.22160

Energy efficient optical tracking for space quantum communication

Eric Vokes·Vinod N. Rao·Elinore Spencer·Rupesh Kumar
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Abstract

Power consumption is a critical constraint for CubeSat based quantum communication, where tracking systems often dominate the onboard power budget. We demonstrate an energy-efficient approach that enables reliable satellite tracking at substantially reduced beacon power by treating tracking as a weak-signal estimation task. Using a closed-loop system with fine steering mirrors and higher-order Kalman filters on ground, we can maintain stable tracking at a transmitted power equivalent to 34 mW over a -60 dB satellite to ground optical channel. Our results show that the resulting penalties on QKD bit error rates and signal-to-noise ratios are negligible, allowing for more efficient power allocation to quantum payloads in CubeSat missions.

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Eric Vokes, Vinod N. Rao, Elinore Spencer, Rupesh Kumar. 2026-02-25. Energy efficient optical tracking for space quantum communication. https://arxiv.org/abs/2602.22160

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