GNSS Satellite (GIOVE-A)


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Tuesday, 19 January 2010

GNSS Picutre Galery

Just a short post this time but an interesting one! Here we provide some links to interesting pictures and videos from different GNSS systems.

Galileo info.
A look at the navigation payloads on the satellites being assembled at EADS Astrium in Portsmouth, England, a video from the BBC.

Glonass launch from December 14, 2009
Roscosmos has announced the successful launch of the Proton rocket carrying three GLONASS-M satellites (in Russian).

The launch occurred on time at 10:38 UTC, on December 14, 2009.

Pictures of the launch.

Video 1 of the launch from RT (Russia Today).
Video 2 of the launch from RT (Russia Today).
Video 3 of the launch from TV Roscosmos.

Beidou/Compass info
The Chinese Government opened a Beidou/Compass Web site today at 12:00 local time "to promote greater public participation and understanding of the Compass navigation satellite [system] development, launch, operation and application." The site is presently in Chinese only.

Beidou/Compass-G1 was launched at 00:12 Beijing Time on 17 January = 16:12 UTC

China Central Television video of launch:

Hope you like these!

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Monday, 4 January 2010

Galileo IOV Schedule

First of all a very happy and prosperous 2010 to all of you!

In 2009 saw very little concrete progress within the Galileo project. Behind the scenes a lot has happened, e.g., the cooperation between the EU and ESA has been improved and a lot of progress was made in the negotiations for the full orbit constellation (FOC) contracts. However, from a (scientific) user point of view this is not very concrete progress at all.

A significant issue with the Galileo project is the lack of an open communication principle. In 2009 I was really positively surprised about how open the GPS system has been regarding the issues with SVN-49. This is quite different from the way how the Galileo project is treating things. This is very surprising and even more so if one considers that GPS is still very much a military system whereas Galileo is a civil system. Thus one would expect much more open communications from Galileo!!

Secondly, also the data policy from the Galileo project is not really transparent. Since 2005 GIOVE-A has been in orbit and ESA has been gathering data from this satellite, and its brother GIOVE-B, using a network of 13 Galileo Experimental Sensor Stations (GESS). In principle this data is available to all ESA "trusted users", a status one can apply for on the ESA GIOVE web site. However, I know several institutes that have applied but never received this status. This is really disappointing, especially since a open data policy would most likely lead to much more interest, and consequently investigations and progress, from the scientific community. The currently employed "closed data policy" is very likely more harmful then helpful for the project. Several world leading scientist who would be interested in studying the Galileo, or rather GIOVE, data do not have access to the data. In this sense the Galileo project is very similiar to the Chinese COMPASS project.

So this brings us to the status of the Galileo IOV phase. In this phase 4 satellites will be launched in two launches. Both launches will be from Kourou using the the Russian Soyuz launcher. The four IOV satellites should, in principle be very similar to the final Galileo satellites. In Summer 2009 the IOV schedule foresaw that launch 1 would take place around September 2010 and launch 2 around February 2011. However, ever since the schedule has been slipping. Of course slipping schedules are quite normal in the space business but the lack of communications around it in the case of the Galileo project are untypical and make people wonder about the reasons for the delays. The latest rumours I have heard, and so far these rumours have always been true, is that launch 1 for the Galielo IOV is now scheduled for May 2011. The reason(s) for this (huge!) delay are completely unclear. But, we can speculate a bit about them....

Interesting is that in the FOC negotiations it seems that for building the satellites the consortium around OHB now seems to be winning against the "favourite" EADS consortium. The OHB consortium includes Surrey Satelite Technology Ltd which was responsible for the very successful GIOVE-A satellite. GIOVE-A was build on-time and within budget. And that was a truley great performance as time was the most critical factor in that case. The performance of EADS in building GIOVE-B was quite in constrast to the this with very significant delays and huge cost overruns. So if we put 1 and 1 together and start speculating a bit, it could very well be that the EU and ESA are a bit disappointed with the EADS performance both from GIOVE-B as well as now for the IOV satellites and are thus now favouring the OHB consortium for the FOC phase. It can also be just "politics" but the GIOVE-B and IOV satellites projects are certainly not one of the "best" we have seen. So there is some room for speculation here.....

Of course, in case the OHB consortium wins this will lead to a very inhomogeneous Galileo satellite constellation as the OHB satellites will most likely be quite different from the EADS IOV satellites. Also most likely the FOC constellation will be build in different phase with different generations of satellites. So when Galileo reaches FOC at least 3 different types of satellite will be in orbit.

In any case these are interesting times but before we see any real Galileo satellites in orbit my bet is that we will have to wait until 2011. So for 2010 the highlights we may expect will come from GPS and GLONASS. The GPS system is going to launch its, long overdue, first Block IIF satellite (currently scheduled for May) whereas the GLONASS system is going to launch its first GLONASS-K satellite (scheduled for the end of 2010).

Meanwhile I hope the Galileo project will become a bit more open both in its communication policy and, even more importantly, in its data policy.

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Thursday, 24 December 2009

GNSS Year in Review 2009

So what happened in the GNSS world in 2009!?

Well....not as much as we hoped for but some progress was made. Most progress was made "behind the scenes".


The most exiting and most "visible" was the launch of the GPS satellite SVN-49. This satellite brought new signals to the GPS system as it carries an experimental payload that allows the transmission of the new (future) GPS signals on the L5 band. The L5 experiment was bitterly needed because of the significant delays in getting the GPS IIF (F for Future) satellites ready. Thus the GPS system was at risk of loosing the L5 frequency allocation if they would not get a satellite up and "beeping" on the L5 frequency. The European Galileo system faced, and still faces, a similar challenge for which the launched the Giove-A and Giove-B experimental satellites. Unfortunately, the experimental character of the SVN-49 satellite actually caused some unexpected ill effects on the satellite on which we reported in our BLOG. This is the reason the satellite is still unhealthy although it is planned to turn the satellite healthy soon. However, the satellite will never perform as good as the other GPS satellites due to its anomaly. Besides SVN-49 also SVN-50 was launched marking the last GPS Block IIR-M satellite launch. The next GPS satellite to be launched will be the of the Block IIF type, currently scheduled for May 2010. An other "sad" event in 2009 was that SVN-35 was taken out of service. This satellite was special as it was one of only two GPS satellites that carries a Satellite Laser Ranging reflector array. The loss of this satellite is a grave loss for the scientific world especially because currently no SLR reflector arrays are foreseen on the GPS Block IIF nor on the first batch of the GPS Block III satellites. Hopefully the second batch of GPS Block III satellites will correct this "oversight" of the GPS system.


The most solid progress was made by the GLONASS system. Firstly, one of the three satellites launched in December 2008, GLO-729, is carrying a brand new SLR reflector array design which is 1.5 times better then the previous arrays. This is very exiting because it allows daylight tracking of this satellite which is an absolute "first" in the GNSS world. So far GNSS satellites could only be tracked by the SLR stations during the night. Furhtermore, an other successful triplet launch took place on December 14, 2009. However, also the GLONASS system did have its problems this year. One of the new satellites launched in 2008, GLO-726, developed a problem with its signal generator. As the satellites planned for launch in September 2009 used signal generators from the same batch as this faulty satellite the September launched was cancelled in order to check the satellites and replace the signal generators. The satellites are now scheduled for launch in February 2010. Nevertheless, the progress of GLONASS remains remarkable and they have managed to stick to the schedule that was laid out in 2005! In the space business that is an really astonishing accomplishment!


On the Galileo front things have been very quiet. Giove-A and Giove-B remain to operate which especially for Giove-A is a great accomplishment as it is well past its design life time. However, the schedule of the In Orbit Validation (IOV) seems to remain a "running target". In June the first launch was planned for September 2010. Meanwhile, rumours say the launch has been postponed until May 2011. The reasons for these delays are completely unclear and a more open communication policy would do the project a lot of good. The same holds for the data policy. Since 2005 Giove data has been gathered but the data is only available to ESA "trusted users". Unfortunately, it is practically impossible to obtain a trusted user status with ESA. So the Giove data is only accessible to a very limited number of institutes and thus limits the scientific analysis of the data. Under the surface a lot of things are happening in the Galileo project. The cooperation between ESA and the EU has been improved although it is certainly still not optimal. And a lot of progress has been made for awarding the contracts. The contracts should have been awarded early in 2009 but the process has, not unexpectedly, taken longer then planned. So also for 2010 visibly nothing much will be happening with Galileo. We will have to wait until 2011, at least.


Some progress was made for the COMPASS/Beidou system but since no data is publicly available I can not say too much about it. To my understanding there is still only 1 MEO satellite (MEO is the typical GNSS orbit) and a couple of GEO satellites. One additional GEO satellite was launched but also one was lost and was drifting through the GEO orbit causing quite some concerns for other GEO satellite operators (GEO is the orbits used for most telecommunication satellites). A "wild" satellite in this orbit is very dangerous and can cause a lot of damage.

The Japanese regional QZSS system is making good progress. The signal generator is currently undergoing in space testing as it is being flown on a GEO satellite. The first satellite will be launched in 2010. In principle three satellites are planned but currently funding for only 1 satellite exists.

The only thing remaing to be said is....
Merry Christmas

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Wednesday, 2 December 2009


So it is time for an update on GLONASS.
As you may have noticed meanwhile the September has been canceled. There have been all sorts of speculations and it was difficult to get any hard facts. As far as we have been able to figure out the reason for canceling the launch lies in the fact that the GLONASS 726, in orbital slot 22, developed an unexpected problem and has consequently been unhealthy since quite some time. The problem seems to be with the signal generator on board of the satellite.

Now you may wonder, what does that have to do with the September launch. Well, as it turns out the three satellites scheduled for launch in September make use of the same signal generator. So as it is "better to be save then sorry" it was decided to send the satellites back to the factory to check, or more likely replace, the signal generators in all three satellites.

We originally thought that this would then also impair the December launch. However, we have been told that the satellites for the December launch used a different version of the signal generator and thus the December launch is "on track". In fact the last of the three Glonass-M navigation spacecraft intended for cluster 41 was delivered to Baikonur on November 27, 2009 by the JSC Academician M.F. Reshetnev Information Satellite Systems. The first two satellites were delivered to the spaceport on 17 and 23 November and are currently in preparation for launch. The launch date is set for December 18. A bit earlier then the normal "Christmas" launches around the 25 and 26 of December.

The September launch is now scheduled for February 2010.
If both of these launches work out as planned GLONASS will get very close to its full operational capabilities (FOC). The picuture gives the current GLONASS status which is already pretty good.

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Monday, 21 September 2009

GLONASS Launch Delay

*** UPDATE *** UPDATE ***
The GLONASS launched is delayed because of a problem with one of the three GLONASS-M satellites. The new launch data is October 29, 2009.
*** UPDATE *** UPDATE ***

The preparations for the next triplet GLONASS-M satellites scheduled for September 25, 2009, are progressing. Roscosmos is releasing interesting videos and pictures from the preparations. This is really exciting since this is, according to my knowledge, the first time that pictures like this are released officially by Roscosmos. A very good and positive development!

Furhtermore, last week the frequencies of two active GLONASS satellites were changed. For the two "antipodal" satellites in plane one, with GLONASS numbers 701 and 728, the frequency channel was changed from 1 to -4. This is an indication that the September launch will put 3 new satellites in plane 1. This is not surprising since it carries the two oldest satellites in the constellation, 701 from December 2003 and 712 from December 2004 with 701 being the first and therefore oldest GLONASS-M satellite. The "modernized" GLONASS satellites that live significantly longer then the first generation GLONASS satellites.

For those wondering what "antipodal" means. In GLONASS these are two satellites that fly in the same orbital plane but with an 180 degrees angle between them, meaning they are on opposite sides of the world. Several years ago the GLONASS system has been kind enough to have given back half of its frequency allocation because those frequencies were interfering with astronomical observations. However, for the GLONASS system, where the satellites are identified based on having different frequencies, this caused a small problem since there were no longer 24 different frequency channels available. However, since satellites on opposite ends of the Earth will not be observed simultaneously by an Earth bound observed the GLONASS system introduced the concept of using the same frequency channel for "antipodal" satellites.

Personally I am very much looking forward to the launch at the end this month as it will further improve the GLONASS performance and bring it very close to the GPS performance. In my "high accuracy" work (I deal with millimeters) we can now clearly see the benefit of using GPS and GLONASS compared to using just GPS.

Happy positioning and timing!

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Tuesday, 8 September 2009

GLONASS Launch Preparations

This is something really cool so I just had to put this link here for you all to see. This link shows the preparation of one of the GLONASS-M satellites that is being prepared for launch. The launch is scheduled for Septermber 25, see my earlier post.

This video has been posted on YouTube by Roscosmos, the Russian Space Agency.

Check it out is is really cool!

Personally I am very much looking forward to the launch at the end this month as it will further improve the GLONASS performance and bring it very close to the GPS performance. In my "high accuracy" work (I deal with millimeters) we can now clearly see the benefit of using GPS and GLONASS compared to using just GPS.

The GNSS future looks bright!

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Wednesday, 26 August 2009

GLONASS Launch Schedule Update

As in 2008 the GLONASS schedule promises again two triplet launches this year. The first one to take place on September 25, just like in 2008. The second is planned for the meanwhile "traditional" Christmas launch around the end of December. The first satellite for the September launch has been shipped to the Baikonur spacedrome and launch pad in Uzbekhistan. The two other satellites will follow in late August and early September.

Currently there are 18 healthy dual frequency GLONASS satellites. With the two triplet launches of this year the constellation should reach the "magical" number of 24 satellites which is the amount of satellites needed to reach to so-called "full orbit constellation" (FOC). However, for FOC each of the three orbital planes of the GLONASS system will need 8 satellites. Currently the planes have 5, 5, and 8 respecitively. So most likely the launch in September will be used to populated plane I which has the oldest satellites. The December launch will then repopulate plane II.

Plane I has two rather old satellites, by GLONASS standards, one from 2003 (SVN-701 in slot 6) and one form 2004 (SVN-712 in slot 7). These might die before the end of this year. The offical planned FOC data is by the end of 2010. In 2010 two more triplet launches are planned again in September and December.

The really exiting part of that will be the launch of the the new platform, the GLONASS-K satellite. One of the 3 satellites to be launched in December 2010 will be a GLONASS-K satellite. The most important features of this new GLONASS satellite generation are:
  • Longer life time, design life time of 10 years
  • Much lighter satellites reducing launch costs and enabling launches with Soyus rather then with the huge and costly Proton launcher
  • Addition of GPS-like CDMA signals.

The addition of CDMA, in paralel to the GLONASS original FDMA signals, will make GLONASS interoperable with GPS (and Galileo). This will enhance the interest and usage of GLONASS even further then its already rapidly spreading usage.

The GNSS future looks very interesting and very bright!

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