Just wanted to give you a little bit more info. I work for the Spanish company that has developed the OSPF, GMV, and although I'm not currently involved at all in this project, from what i know, the following statement: "around 5% of the Galileo capacity is lost to software problems likely in the Orbit Synchronization Processing Facility (OSPF), run by GMV." is not fully true. The OSPF receives data from sources (From my limited knowledge, time stations in order to generate the ephemeris), and it looks like the problem was not in the OSPF code but in one of these time stations sending the data.
The July Galileo Outage: What happened and why
41–50 of 63 posts
Re: The July Galileo Outage: What happened and why
#42My current impression from reading this article is that SpaceX could create a better GNSS than Galileo in a year as a side project - not because of their cheap launches, but because of their diy development culture. I am stunned by the level of organizational inadequacy of allowing such critical parts of the system to be developed by not just a contractor but a chain of subsidiary contractors, with feedback cycles that move at the speed of corporate communication. My expectation now is that Galileo will never catch up to GPS and will eventually be forgotten.
Re: The July Galileo Outage: What happened and why
#43My current impression from reading this article is that SpaceX could create a better GNSS than Galileo in a year as a side project - not because of their cheap launches, but because of their diy development culture. I am stunned by the level of organizational inadequacy of allowing such critical parts of the system to be developed by not just a contractor but a chain of subsidiary contractors, with feedback cycles th…
Perhaps a good lesson that the opposite of “move fast and break things” is “move slowly - but still break things”.
Re: The July Galileo Outage: What happened and why
#44Earlier quoted context omitted.
I gather the US GPS system has "Autonav mode" where each satellite has long-term ephemerides, allowing 60 days of reduced-precision operation if the ground segment fails. Does Galileo have no such thing, or had the errors propagated into such data by the time someone sounded the alarm?
The 60 day long-term ephemerides were the older sytem. Autonav on the current GPS satellites is considerably fancier - basically, the satellites carry out ranging measurements between each other and compute their own updated clock and ephemeris solutions on the satellites themselves in a distributed fashion. Specced to provide essentially full accuracy for something like six months, minus ionosphere estimates which c…
> As far as I can tell, Galileo has nothing like this. They have a small buffer of future ephemeris data, but the ground segment failure here was so long that it completely ran out. Their approach seems to be full accuracy or why even bother.
It's probably easier to say "our system being down won't be catastrophic" when it's one of 4+ systems rather than one of one, like GPS was.
Also probably not inaccurate to say that the US military cares more about what happens after the nukes start falling than the ESA does.
Re: The July Galileo Outage: What happened and why
#45Is 1cm accuracy part of Galileo system already operational? If so, why our phones and other devices cannot utilise it yet?
[deleted]
Re: The July Galileo Outage: What happened and why
#46My current impression from reading this article is that SpaceX could create a better GNSS than Galileo in a year as a side project - not because of their cheap launches, but because of their diy development culture. I am stunned by the level of organizational inadequacy of allowing such critical parts of the system to be developed by not just a contractor but a chain of subsidiary contractors, with feedback cycles th…
Perhaps a good lesson that the opposite of “move fast and break things” is “move slowly - but still break things”.
Move slowly and be unable to fix things fast.
Re: The July Galileo Outage: What happened and why
#47Just wanted to give you a little bit more info. I work for the Spanish company that has developed the OSPF, GMV, and although I'm not currently involved at all in this project, from what i know, the following statement: "around 5% of the Galileo capacity is lost to software problems likely in the Orbit Synchronization Processing Facility (OSPF), run by GMV." is not fully true. The OSPF receives data from sources (Fro…
Hi - thanks for this (author here). What I mean is, currently, around 5% of the satellites on average broadcast NAPA status. I did not refer to the big outage with this statement, I mean to ongoing developments. Or perhaps you are referring to the same thing & in that case it is entirely possible that the NAPA flag gets raised because the ephemeris is being generated from stale data. Do you know? Thanks!
Re: The July Galileo Outage: What happened and why
#48Re: The July Galileo Outage: What happened and why
#49The "instantaneous violations" link is dead -- I was hoping to learn what that means!
back up, thanks! It is on our experimental node. What is means is: the Galileo service definition regards a 'dilution of position of >6' to be problematic, but only if this happens for more than 77% of the time. The instantaneous bit is "well it is >6 NOW".
Re: The July Galileo Outage: What happened and why
#50Earlier quoted context omitted.
I gather the US GPS system has "Autonav mode" where each satellite has long-term ephemerides, allowing 60 days of reduced-precision operation if the ground segment fails. Does Galileo have no such thing, or had the errors propagated into such data by the time someone sounded the alarm?
The 60 day long-term ephemerides were the older sytem. Autonav on the current GPS satellites is considerably fancier - basically, the satellites carry out ranging measurements between each other and compute their own updated clock and ephemeris solutions on the satellites themselves in a distributed fashion. Specced to provide essentially full accuracy for something like six months, minus ionosphere estimates which c…
Hi makomk,
(author here)
Indeed, Galileo has nothing like this. The GPS solution sounds exceptionally fancy, and it may go a long way to explaining where all those billions of USD/year go :-) Do you know if it has ever been tried for real? Thanks!