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Iphone reaches the sky … a game changer?

You’ll need to “search” for a satellite, pointing your iphone to the sky because of the feeble communication link. Yet, the simple fact that you can use a satellite from it is amazing. Image credit: Apple

Apple recent announcement of the iPhone 14 capability to relay an emergency message using satellites is not a novelty in the sense that no-one has thought about it. Actually companies like T-Mobile and Verizon announced they were working to enable this feature. What is new is that the iPhone 14 will be the first phone ot have this capability.

Connecting to a satellite network is more difficult than connecting to a cellular radio tower because of … distance. The more distance from the receiving antenna and the more power is required to send the message. A cellular radio tower may be a few km away from your cellphone (in a urban environment it will be closer), a satellite will be over a thousand km away! In the case of the iPhone the message is sent to a Globalstar satellite that orbits 1,414 km over the Earth surface (876 miles). These satellites are called LEO, Low-Earth Orbit because they are orbiting close to the Earth surface but “close” is still over 1,000 km. Actually, these satellites keep moving (there are 48 of them in the Globalstar constellation, plus 4 spare in case of a faulty one) using 8 orbital planes to ensure a coverage from 70° North to 70° South. This means that the distance of 1,414 km is the shortest possible distance (when the satellite is exactly over your head) and that in most cases it will be greater.

You can reduce the power required by

  • increasing the dimension of the antenna
  • beaming it on the receiver

Obviously, when dealing with a smartphone you do not really have ways to increase the antenna dimension (you wouldn’t want to carry a satellite dish along with your phone, would you?).

Aligning the internal antenna to beam the message right to the satellite required you to know where the satellite is at that specific time (and it will keep moving!). However here Apple has found a solution. The iPhone screen will display an image with a dot (look at the picture) to indicate the position of the (closest) satellite and you will have to align the phone to it. Smart, isn’t it!?

Even with this trick the distance remains huge but there is still something that can be done when you don’t have a sufficiently large antenna and a sufficiently powerful signal: you can decrease the communication speed. This is what the iPhone does, so that your message (and it has to be a short one) will take a few seconds to be transmitted (versus a few milliseconds when you are using a cellular radio tower in the vicinity). If transmission is bad, like under the canopy of a forest (leaves eat -adsorb- the electromagnetic field thus reducing the signal power) the transmission may take as long as several minutes …

Anyhow, from being isolated and cut out from the world when you need help to be able to send an emergency message is a no brainer and you would be more than willing to wait for a few seconds -even a few minutes- for the transmission to go through.

Once the message is received by the satellite it will be relayed, in a few milliseconds, to a receiving Earth station (they have huge antennas tracking the satellites) and from there to the persons you have indicated as emergency contacts.

What is really interesting is that for the first time a “normal” phone will be able to connect to a satellite network providing you with (almost) complete coverage on the planet. A real game changer in terms of safety.

It could also prove to be a first step in the mass market exploitation of the growing satellite networks, something that will -most likely- become an integral part of 6G.

About Roberto Saracco

Roberto Saracco fell in love with technology and its implications long time ago. His background is in math and computer science. Until April 2017 he led the EIT Digital Italian Node and then was head of the Industrial Doctoral School of EIT Digital up to September 2018. Previously, up to December 2011 he was the Director of the Telecom Italia Future Centre in Venice, looking at the interplay of technology evolution, economics and society. At the turn of the century he led a World Bank-Infodev project to stimulate entrepreneurship in Latin America. He is a senior member of IEEE where he leads the New Initiative Committee and co-chairs the Digital Reality Initiative. He is a member of the IEEE in 2050 Ad Hoc Committee. He teaches a Master course on Technology Forecasting and Market impact at the University of Trento. He has published over 100 papers in journals and magazines and 14 books.