The European Space Agency (ESA) has finished testing of an innovative laser communication platform that speeds up data transfer from orbiting satellites.
The technology will be demonstrated live for the first time in October this year to communicate with Nasa’s Moon orbiting spacecraft.
The robotic Lunar Atmosphere and Dust Environment Explorer (LADEE), which is scheduled for launch in September this year, carries an advanced laser system that enables transmitting and receiving pulses of laser light.
To communicate with the spacecraft, ESA will use its Optical Ground Station on the Spanish island of Tenerife. Together with two other US-based terminals, the station will be able to communicate with the spacecraft in lunar orbit with unprecedented speed.
Instead of conventional radio waves, the data will be transferred via infrared light beams at a wavelength similar to that of fibre-optic cables.
“The testing went as planned, and while we identified a number of issues we’ll be ready for LADEE’s mid-September launch,” said Zoran Sodnik, manager for ESA’s Lunar Optical Communication Link project.
“Our ground station will join two Nasa stations communicating with the LADEE Moon mission, and we aim to demonstrate the readiness of optical communication for future missions to Mars or anywhere else in the Solar System.”
Laser pathways are seen as the next step in telecommunications, increasing the data transfer capacity far beyond the capabilities of currently used radio waves. Engineers have dealt with the growing demands for speeding up data transfer and increasing the capacity by using higher radio frequencies and new electronic systems. However, the limits of radio communication might soon be reached.
On the other hand, passing data through high-frequency laser terminals opens entirely new horizons. The technology has recently been tested by several projects. One experimental payload is currently on board Alphasat, the giant European telecommunications satellite launched earlier this month.
"The development in laser data transfer is a quantum leap in satellite communication,” said Gerd Gruppe, executive board member of the German Space Agency, who has been overseeing the development of Tesat, the laser terminal aboard Alphasat.
The Tesat terminal is capable of transporting 1.8GB of data per second, equivalent to 130 DVDs, over tens of thousands of kilometres.
The geostationary Alphasat, orbiting at the altitude of 36,000km will use this technology to communicate with satellites in low Earth orbit at an altitude of 200 to 2,000km.
In the future, engineers believe laser communications at near-infrared wavelengths will enable download of massive amounts of data from spacecraft orbiting not only the Earth, but also Mars or even more distant planets, decreasing the time needed for the signal to travel the distance.
The laser communication terminals are also lighter, smaller and need less power than today’s radio systems, promising to cut mission costs and provide opportunities for new science payloads.