Mark Stevens of MIT Lincoln Laboratory said that this will be the first time that they will present both the implementation overview and how well it actually worked and the on-orbit performance was excellent and close to what they predicted.
Stevens added that communicating at high data rates from Earth to the moon with laser beams was challenging because of the 400,000-kilometer distance spreading out the light beam, and it was twice as difficult going through the atmosphere, because turbulence could bend light that would cause rapid fading or dropouts of the signal at the receiver.
The demonstration used numerous techniques to achieve error-free performance over a wide range of optically challenging atmospheric conditions in both darkness and bright sunlight. A ground terminal at White Sands, New Mexico, used four separate telescopes to send the uplink signal to the moon where each telescope was about 6 inches in diameter and fed by a laser transmitter that sent information coded as pulses of invisible infrared light and the total transmitter power was the sum of the four separate transmitters, which resulted in 40 watts of power.
Steven said that they demonstrated tolerance to medium-size cloud attenuations, as well as large atmospheric-turbulence-induced signal power variations, or fading, allowing error-free performance even with very small signal margins.