Starlink: Tech from Above

Ever wondered how people in deserted places watch TV, or check their E-mails, WhatsApp their families or play videogames? Well, the fact is: they don’t, until now! This era of space exploration is opening doors to new technologies that make it so you can access the Internet from virtually anywhere. Setting up takes 5 minutes and none of the 4,000 satellites in orbit will let you down. So: How does it work? And why will it change communication forever:

Announced in 2015 by Space Exploration Technologies (SpaceX), the Starlink satellite constellation is currently made up of around 4,100 of them, of which around 3,800 are operational. Today, Starlink has around 1.5 million users within 54 countries and has become one of SpaceX’s primary sources of income. There are five service plans of which to choose from:

So, how does it work? Well, the service starts in the satellites who’s signal scatters through the atmosphere and reaches your home. To understand the principles of signal reception, let’s take a look at the example of a dipole antenna. This is the simplest model of a receptor in which the apparatus is made of a sequence of conductive rods. Each rod generates an electromagnetic field by applying an AC current the two conductive substances in either side. The same way they emit radio signals they can also receive pulses and convert them into digital content, like radio or the TV.

In the case of Starlink, the antenna dish receives radio signals with encoded internet signals rather than from the fiber optic fiber cables that would otherwise be used in large cities. Also, worth noting that the same way a radio emission system can generated waves, it can also be reversed to receive encoded signals.

In addition, thanks to its “phased array” technology present in the Starlink dishes it can steer its signal beam digitally without needing to move an inch of its physical body. This is the same system used by military aircraft for their radar signals. The diagram bellow (far left) shows how the different pulse intensities combine to steer the wave and create a “beamforming” signal that propagates with greater precision (aero foil shape bellow):

The advantage of Starlink over many other operators is their satellites are located in low earth orbit (at only 550km of altitude) which means their signal delay is very inferior to that of Geosynchronous satellites which are 36,000km away. SpaceX manufactures and launches their satellites with their Falcon 9 rockets which can fit 60 at a time. Each satellite weights over 260kg, measure 7m meters in length when unfolded and have a lifespan of over 5 years. Their ionic propulsors require only a small quantity of krypton and electricity from its solar panels to run. It uses its propulsion to maneuver and make corrections to its trajectory while also keeping itself in orbit.

Currently, Starlink satellites are equipped with the best communication technologies of any internet satellite in orbit. However, with the advancing of laser technologies it is probable that gen2 Starlink satellites will substitute radio based inter-satellite communication with laser. Lasers can send much more data and with a greater energy efficiency, thus, being the next large step for Starlink and other internet communication systems.