Thursday, December 15, 2016

Galileo : the european GPS between service – Release

update 15 December : The services of Galileo are officially activated on Thursday. The few people who are already equipped with a chip compatible can geo-tag with the european satellites… The others must wait until these chips are spread on the market of smartphones, cars and other GPS devices.

On Thursday 17 November, the Cnes could shout cocoricorbite : so that France would send into space its tenth astronaut from Baikonur, in Kazakhstan, an Ariane rocket took off from Kourou in French Guyana, taking with it four Galileo satellites. Now, with “a constellation of 15 satellites operational, the GPS system european is almost ready for use.

re-light engine

The launch of the end of the year has first represented a technical challenge : it is not often that one launches four satellites of 715 kilos, with a single knuckle to drop to 23 000 km altitude. To win this altitude, it was necessary to first pull out of the earth’s atmosphere to enter orbit, and then fly three hours with all engines off – in the “ballistic phase”, without any constraints – before relighting the engine of the upper floor (the head of the rocket) (detail in PDF).

according To diagram Arianespace

This maneuver is rare, already used to launch the Rosetta spacecraft to its comet in 2004, for example, requires the use of a rocket more advanced than the standard model. This time, it was the Ariane 5 ES, which previous missions were to take a cargo of automatic replenishment (the ATV) to the international space station between 2008 and 2014. Since then, she was no longer anything… But with Galileo he will regain the service : this quadruple launch in November 2016 will be followed by two other similar missions in 2017 and 2018, to further enrich the Galileo constellation.

First signal in December

The goal is to have thirty satellites in orbit by 2020, in order to ensure a location-based service stable and powerful… But fifteen are already enough to put it on the road. Luckily, the figure has just been reached. 14 satellite had been launched so far, including 1 out-of-service and 2 on an orbit half-assed that does not allow them to be used by the boats for their rescue operations, which is 11 satellites functional. With the 4 new ones launched in mid-November, the account is good.

as Soon as the first signals will come in the month of December if all goes well, the manufacturers of GPS chips (such as Qualcomm or Texas Instruments to the largest) will be able to make chips that are compatible. It will then be up to the manufacturers of smartphones, cars, GPS devices for hiking or driving to install these chips to the general public can take advantage of this positioning system european. As it is interoperable with other systems, such as the american GPS and Russian, the devices can be bi – or even tri-compatible and freely switch from one signal to another according to the reception conditions.

Prévision of the 30 Galileo satellites that should être in orbit in 2020.

Forecast of the 30 Galileo satellites should be in orbit by 2020. Image Pierre Carril. ESA

triple the competition

The manufacturers are they going to play the game ? Jean-Yves Le Gall, president of Cnes, believe in : “We will put in place and set the stage for industrialists to come in to play. And our scenery is much better than that of the other theatres,”, gave it a few days before take-off. First, Galileo will enable a more accurate location than the competition, of the order of one meter for its free service to the general public, where the current competitors “make the decametric”. The accuracy goes up to the centimeter to the paid version and commercial use of Galileo, and it is necessary to add the dating of the signal, as well as a advantage unique and exclusive : its authentication. It is a kind of security key, sent by the satellites with the signal locator, which allows you to“to have the guarantee that the signal is coming from Galileo and not a lure”. With that, it’s impossible for example to hack into a smartp hone in order to distort its location : the Cnes think it will appeal to insurance companies, who need to check the veracity of the statements of their clients in the event of a claim before compensation.

The competition is fierce in the area of geolocation. It is now operating the american system, Global Positioning System, which gave the generic name of GPS and the Russian Glonass system – these two devices with more than thirty years – the more the chinese Beidou arrived on the market in 2000. At its launch, Galileo will be more accurate, the more resistant to disturbance, and the better designed for locations cashed, such as “urban canyons”, these streets lined with buildings in which the satellite signal has a hard rush, because Europe is flying at high altitude. Where the american GPS turns at 20 000 kilometres of average altitude, Galileo climbs to 23 222 kilometers, which gives him a better angle.

A Galileo satellite. Image GSA (the european GNSS Agency, who will be responsible for operating Galileo)

But competing systems, modernize them also gradually replacing their satellites. Russia began to renew its stock by launching the first next-generation satellites, Glonass-K. Americans share their network with satellites of transition while waiting for the big wave of “GPS III” from 2017. As for Beidou, it only works in China for the moment, but enlarges its fleet of satellites, offering global coverage by 2020. It will be for Galileo to keep his advantage by incorporating his own improvements on a regular basis.

30% of the european GDP

many Of the actors seem to be in any case on the starting blocks. Since may, Galileo is recognized as the system of maritime navigation by the international maritime Organization (IMO). Its signal dedicated to search and rescue operations may, therefore, be used on boats, and even respond to the distress beacon of the castaways. The precise localization of particular interest to the transport sector, such as the autonomous cars that will soon conquer the world, or taxis, busses, trains : “with Galileo, a train will be able to see in what way it is” among multiple parallel pathways, which promises The Gall, according to which the european commission estimates that 30% of the european GDP, will depend on GPS services by 2030. Finally, when you say GPS services… We should talk about “location based services”. the “It’s going to take time”, admits Jean-Yves The Gall, but in the long term “the aim is no more ta lk of “Galileo is the european GPS”, but GPS is the Galileo of”american.” An ambition to the extent of the investment – € 10.5 billion over the period between 2008 and 2020.

Camille Gévaudan

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