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Design and performance of a 40W uplink laser transmitter for NASA's O2O laser communications mission

January 14, 2025

Conference Paper

Author:

Katia Shtyrkova

…

Topic:

laser communications

R&D group:

Optical and Quantum Communications

Summary

NASA's Orion Artemis II Optical Communications System (O2O) will provide operational laser communications between the ground and lunar orbit for the Artemis II crewed mission. In this work we describe a 40 W ground-based laser transmitter for the O2O system. The uplink transmitter operates in the optical C-band and uses an energy-efficient 32- PPM modulation format. Four spatial diversity channels are time-aligned and combined in the far field. Each channel produces up to 10 W of output power and contains both the communications signal and the 7 kHz modulated beacon signal required for acquisition. The transmitter delivers data at 10 Mbits/s and 20 Mbits/s channel rates, corresponding to the 250 MHz and 500 MHz slot rates respectively.

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Summary

Design and performance of a 40W uplink laser transmitter for NASA's O2O laser communications mission

Coherent combining of a 4 kW, eight-element fiber amplifier array

July 15, 2011

Journal Article

Author:

Charles X. Yu

…

Published in:

Opt. Lett., vol. 36, No. 14, 15 July 2011, pp. 2686-2688.

Topic:

optics

R&D area:

Advanced Technology

R&D group:

Laser Technology and Applications

Summary

Commercial 0:5kW Yb-doped fiber amplifiers have been characterized and found to be suitable for coherent beam combining. Eight such fiber amplifiers have been coherently combined in a tiled-aperture configuration with 78% combining efficiency and total output power of 4kW. The power-in-the-bucket vertical beam quality of the combined output is 1.25 times diffraction limited at full power. The beam-combining performance is independent of output power.

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