How much does this increase GNSS robustness ?
All sorts of entities meddle with GPS, does this make it twice as hard to disrupt ?
How much more does it cost to add Galileo to GPS in an aircraft or missile ?
The European Space Agency (ESA) has celebrated the Galileo satellite navigation system meeting civil aviation standards governing flight phases from take-off to landing and explained how the feat was done. The requirements around Safety-of-Life operations are laid down by the International Civil Aviation Organization (ICAO) …
All sorts of entities meddle with GPS, does this make it twice as hard to disrupt ?
How much more does it cost to add Galileo to GPS in an aircraft or missile ?
Galileo has PRS, which is a secondary encrypted signal for military and public services. It's impossible to guarantee spoofing won't take place but this makes it harder. The cost is negligible and even the most basic new receivers generally support Galileo (though not PRS). You can check (if you own an iPhone or Android device with GNSS) by downloading something like GPS Test; depending on your chipset, you'll probably also see GLONASS and might see BeiDou as well as ground-based assistance beacons depending on your device and location.
Generally that's what SBAS is for the USA has WAAS and Europe has EGNOS
It both increases the accuracy a bit but also gives a stronger confirmation signal that you aren't being spoofed.
The original purpose for WAAS was actually to ensure that the GPS signal was real, the FAA got really nervous about that. EGNOS was more important to give accuracy at high latitudes
In the USA, FCC rules cover receivers as well as transmitters and emitters. 10 years ago, GLONASS and Galileo were not authorized for use in the USA, and the commissioning manifest on your device typically disabled GLONASS and Galileo when you were located in the USA, in the same way that you weren't able to transmit / connect / emit on un-authorized frequency bands. Flying out of Europe, Galileo would be visible: landing in the USA Galileo would not be visible.
What's the situation now? Did GLONASS AND Galileo eventually get waivers or approval?
But satnav systems only receive, they do not transmit. Those radio signals can be picked up in the US whether they are “authorized” or not. What business does the US have to demand that your device’s ability to receive those signals be disabled?
Idiotic bureaucracy maybe?
Or they are interested in being able to stop you from using navigation aids on US soil, so they don't want you to be able to receive other signals.
That's how government logic works.
Complex systems will inevitably degrade or fail, particularly if they're exposed to the elements (or space, as in this case).
The goal is of course to make them as reliable as possible, but it's far worse to sustain a failure and not be able to detect and report it.
Aircraft have many layers of redundancy, a single GNSS failure is not critical under normal circumstances. Even if all satellite navigation equipment fails, it will be perfectly possible to continue flying, but it will certainly make it harder to navigate. At least for now - traditional ground-based radio navigation stations (such as VOR/DME) are increasingly falling out of favor.
We'll see if recent GNSS jamming events can change that, so more resilience is built.
Has anyone considered, that good old Newtonian gravity is perfectly fine for aiming the most advanced space probes at the furthest corners of our Solar System? Including playing carefully-calculated celestial billiards games involving rendezvoux with various planets to pick up momentum along the way?
Whereas satnav systems would not have the accuracy they have without applying Einstein’s time-dilation corrections? So you need his most advanced General Theory of Relativity to help you, your family and your common-or-garden car get to your tourist/vacation spot?
Did you notice that Neil and Buzz completely missed their large target landing area, and even as recently as last month it was considered an impressive achievement when a rover landed within 100m of target? And that's just the moon, our nearest neighbour. If you want to fly past a distant body like Titan then 100km accuracy is probably good enough. Meanwhile GPS can get me close enough to my destination that 1.5m social distancing is an issue.