The NASA since the 1950s using radio frequency to send data between Earth and space . This has been the system they have used for almost 70 years, but now its successor is finally here in the form of a laser . It will be this summer when we can see in action the Laser Communications Relay Demonstration (LCRD) , which will show how far they can improve communications.
Radio frequency waves and infrared light are electromagnetic radiation . The only thing that changes is their wavelength, where both are invisible to the human eye . In its missions, NASA modulates the data and converts it into electromagnetic waves, which travel from spacecraft to stations on Earth, one of which is in Madrid.
The laser allows you to send more information at once
The problem with radio frequency signals is that they spread out. With infrared light and lasers, which are optical signals, data can be packed into narrower frequencies, so stations on Earth can receive more data at once. In this way, since both radio frequency and infrared light signals travel at the speed of light, the only thing that can be improved is the amount of data that can be compressed by sending data.
Thus, the laser signal is more powerful and allows more information to be stored, in addition to reducing interference and improving safety by concentrating the signal to a specific area and preventing another nearby geographical area from capturing it. The downside of this is that you have to be extremely precise when aiming, since by deviating just a fraction of a degree, the signal will not reach the destination.
To avoid problems with the signal, the LCRD satellite, located at an altitude of 35,400 km in geostationary orbit, will be testing this laser system for two years through numerous experiments. Communications will be made with the California and Hawaii stations as simulator clients to see if there is interference of any kind. Subsequently, tests will be carried out with space missions.
1.2 Gbps – up to 100 times faster than now
The first terminal, called the Integrated LCRD Low-Earth Orbit User Modem and Amplifier Terminal (ILLUMA-T) , will arrive on board the International Space Station in 2022, and will allow speeds of 1.2 Gbps between the satellite and the station. That speed will also be reached between the satellite and base stations on Earth.
The LCRD and ILLUMA-T are an evolution of the communication system that NASA tested with lasers on the Moon, and which reached speeds of up to 622 Mbps. With the laser, it will be possible to receive high resolution images and 4K video much more faster than before, with an improvement of between 10 and 100 times over current radio-based systems. In comparison, a map of Mars takes 9 weeks to ship with current systems, and with lasers it would take just 9 days.
In addition to speed improvements, the use of lasers allows you to use equipment that takes up less space, weighs less, and uses less energy. With this, more scientific instruments can be equipped, and battery consumption is significantly reduced. Therefore, they hope that in the coming years the laser will become the default way to send and receive data in space, as if it were a series of space.
