Where is GNSS heading

We currently only have GPS flying complete and after many years working with GLONASS (at ESA/ESOC we are one of only two worldwide Center’s estimating GLONASS orbits continuously for over 7 yrs), I am not too optimistic that GLONASS will deploy a complete constellation anytime soon. We have been going from GLONASS constellation of 14 to 11 to 14 to 12 satellites for all these years the types of satellites change, as the old ones are decomissioned and new ones launched, but the numbers are very stable, and its not positive so far!

So we just have GPS and the politics of the GPS upgrades and the longevity of the satellites has kept new features and upgrades from being introduced. Maybe the problem was the obsolete GPS Control System which is being upgraded in Sept/Oct 2007 (I will write more about this soon). It is possible that the new control system will allow the constellation to better manage increasing number of satellites so that the new satellites waiting on the ground can be launched soon.

In general, though, I am not positive that this will happen due to overall decisions based on this so-called ‘launch on need’ policy. This idea is not to launch unless it is needed due to an incomplete constellation. Of course we are far away from having an incomplete constellation, on last count we have 31 satellites flying, the old PRN23 has just been introduced as PRN32 and only PRN15 appears unused. So at this rate we will not see significant new capabilities until many more years go by!

To me this is really unfortunate but also an opportunity for our Galileo. IF we can somehow get Galileo up and running in the next 5 to 6 yrs with its extra frequencies and measurements it could be possible that LBS (Location Based Services) companies will adopt them and make Galileo the GNSS leader. GPS will be the backbone of any LBS system, to be sure, but any added edge that using Galileo can add would make the European constellation a very important player in the GNSS world much faster than expected. This would also help to change the GPS attitudes and so that all new satellites get launched and introduced as quickly as possible.

What do you think?

One Response to “Where is GNSS heading”

  1. nacho Says:

    The problem is that we have seen these exciting GLONASS developments before and nothing ever happens, more satellites get decommissioned than are launched leading to a difficult situation for constellation support.

    Today we received this meesage which proves my point:

    This week, 5 GLONASS satellites were decommissioned:
    794 in orbit slot 2
    789 in orbit slot 3
    711 in orbit slot 5
    792 in orbit slot 21
    798 in orbit slot 22
    These satellites had been set unhealthy for varying periods of time, since
    9 July 2006 in the case of 711 to as recently as 17 November 2007 in the case
    of 792.

    The 3 new satellites launched on 25 December 2007 still await commissioning.

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