The American Surveyor

Conference Review: GNSS – Guess Who’s Coming to Dinner? – Part 2

Geopolitical Posturing at the 3rd Meeting of the International Committee on GNSS

“We can lick gravity, but sometimes the paperwork is overwhelming.”
– Werhner von Braun

GNSS constellations – two in the sky, two on the ramp, and possibly three more in the hangar; it is going to get crowded up there (not to mention in the inner workings of future receivers). How these systems will (or will not) play with each other is subject less with technical issues as it does with “geo-geo-political” posturing. In the May 2009 print issue of American Surveyor; part 1 of this article, we examined the subject from the perspective of the December 2008 meeting of the International Committee on GNSS (ICG), the premier forum for the constellation providers to get together, make official statements, compare notes, schmooze, and posture. And we look at what the repercussions that such posturing may (or may not have) on the surveying industry…

GPS – Old (and new) Reliable
An overview of U.S. policy was given by Michael Shaw, national PNT (position navigation and timing) office director and with a constellation overview by David Goldstein of the UASF. What else can they say?: no news is in some ways good news when it comes to a system that is up and running, outstandingly reliable, and very much on track for  planned upgrades.

L2C should be fully deployed by 2016, L5 by 2018, and L1C by 2021. On the subject of the future of the P/Y code, the U.S. delegation declined to be quoted directly, deferring to the official national register notice (http://edocket.access.gpo.gov/2008/E8-11148.htm) but offered a clarification that the signal would not necessarily be “switched off” in 2020, but that it may be discontinued in its current form at that time (or possibly continued in an altered form).

The U.S. delegation offered up many questions to the other delegations on the subjects of compatibility and interoperability.

Glonass – Back in the Black
Another great summary from the affable Sergey Revnivykh of Ruscomsmos was all smiles coming so soon after the announcement of a multi-billion dollar (don’t ask me how many rubles that is) injection of state funds into the accelerated launch program (up to 24 by 2010).

In an overall light hearted presentation, the closest such a stuffy audience came to a belly laugh was when Sergey showed a slide of the Glonass Organizational Chart; lifted and adapted directly from the U.S. PNT Organizational Chart to make a point that the drivers and stakeholders are the same in both “dual use” systems.

An overview was given of the SDCM augmentation system in development (think WAAS in Russian) and more on the news that the Glonass system will likely some day move from the FDMA (channel access method) to the CDMA system used by GPS. But on that note he qualified that by indicating that it might take a long time; “I would not wait so long” he said (cautioning us to not hold our collective breaths). Note: at time of printing Mr. Revnivykh has since made statements at subsequent GNSS meetings in Europe alluding to actual timelines for CDMA implementation.

Offline I asked Sergey about the news that a recent bill in Russia has characterized Glonass as both “critical infrastructure” and “mandatory” for some state uses. He said “if we pay for this system we should expect our people to use them”. He further clarified that this was on the grounds of not only cost-benefit, but consistency, and public safety.

India – Two More Systems
India is steadily working on a regional augmentation system GAGAN (think WAAS in Hindi) and yet another new ranging system IRNSS. The first satellite of 7 in strictly regional IRNSS should go up in 2009. The final configuration should be 3 in geostationary orbit and 4 in an inclined geosynchronous orbit keeping all within radio range of the sub-continent.

Japan’s QZSS
The proposed 3 satellite constellation will be of the HEO method (described in last month’s part 1 of this article). It is mainly designed as a timing and augmentation system, with the advantage of having at least one satellite very high in the sky, seeable in urban canyons, but not foreseen as a standalone ranging service. It had recently been reported that tracking results of a test satellite have shown better than expected results (for HEO stats) in returning precision orbits.

QZSS is being designed, according to the Japanese delegation, with “Complete compatibility and interoperability with existing and future modernized GPS signals” and an experimental signal that should be interoperable with the proposed Galileo E6 signal. QZSS will likely only be visible to a very narrow slice of the continental U.S. but that the inclusive research may someday prove useful to U.S. concerns.

Galileo & EGNOS
EGNOS is an augmentation system of 3 GEO (see description of GEO in previous article) satellites that service Europe and much of Africa and has been in service since 2005 (think WAAS in Euros). It is designed to augment GPS and eventually Glonass and Galileo.

The summary of Galileo had more to do with organizational changes than dramatic technological milestones. The model for services is still in flux. There will be a free and open segment, a safety of life segment, a public regulated service, and (possibly) a commercial service. The specter of a commercial service and the uncertain timeline for release of the Interface Control Document (ICD) leaves the potential manufacturers a bit of a lurch as to how to proceed. Let’s hope there is some concrete news soon.

Nigeria
All kidding aside, there is a legitimate Nigerian space-based program that began with NigeriaSat-1 in 2003. This earth observation satellite has made a great difference to a country wrestling with tremendous sustainable development issues, as well as substantial valuable natural resources. There is a serious exploration of yet another new regional augmentation system as well.

End User Round-Up
The ICG wanted to provide as wide a view of end uses as possible emphasize  the drivers for upgrade of existing constellations and development of new ones.  These presentations can be found online at: http://www.unoosa.org/oosa/SAP/gnss/icg/icg03/presentations.html
Two presentations on high precision, decidedly on the technical side were from Dr. Stuart Riley, Engineering Product Development Manager for Trimble, and Dr. Javad Ashjaee (see sidebar) who both touched on successes and challenges in adding new constellations to product lines.

The biggest eye opener on the subject of high-precision positioning was the FIG report on the cost-benefits of high precision using Australia as a case study. Matt Higgins, FIG Vice-President presented the astounding figures; the largest gains would be from agriculture and mining. He quipped that if the idea of an RTN covering the entire continent of Australia were entertained it might cost several hundred million dollars, but that the entire network cost would be offset in carbon credits alone, and total savings would be in the billions.

Of several presentations on the benefits to science from GNSS, one by Dr. Kaye Shedlock, Earthscope Program Director at the National Science Foundation (Plate Boundary Observatory, or PBO is the multi-million dollar GPS offshoot of Earthscope) lauded GNSS for providing actual surface movement data (contrasting the purely computed movements from traditional seismic methods). Segments of the sometimes stodgy seismology crowd have been slow to embrace GNSS.

Captain Joe Burns of Unite
d Airlines outlined more than a dozen systems employed by aviation that already integrate GPS for improved safety and fuel savings and that GPS will likely be the element that frees up aviation from the restrictive “route” systems.

One of the most telling testimonials was that from Greg Turetsky of Sirf, a manufacturer of GPS chips for consumer and other products. He spoke of consumer adoption on the scale of hundreds of millions of units. Now so widespread, consumer GPS is not a matter anymore of “do you have GPS?” and it is “how many GPS units do you have?” He was very clear in his view that for the consumer, multiple constellations may hold little added value beyond redundancy, only so many channels are of direct economic benefit.

When asked further about the direction the consumer GNSS product developers might be taking with respect to new constellations, Greg Turetsky went on to contrast the concepts of hardware based receivers and software based receivers. The software receiver (of the near future) does all signal processing on a more standardized processor and requires only a minimum amount of front-end hardware; therefore adoption of new services would in theory be less expensive to less time consuming to roll out. It makes one wonder if the producers of the survey-grade gear are seeking the same path, or alternately if those that work towards software based solutions (outside of current production lines) may be able to roll out a new wave of low cost survey receivers?

World economy, oil, and angst
Mention of current world economic woes may have only been in passing in the course of the formal presentations, but dominated many “offline” discussions. For instance an interesting contrast to the jubilant announcements in the fall of the $2.5B commitment towards the Glonass program from the Russian Federation (during the peak period of oil prices) with the offline comments by some members of the Russian delegation that the recent drop in the oil market puts a lot of programs into question. What a difference a few months can make. Officially though, things are full steam ahead for Glonass.

Alternate takes on how the economic woes may impact the various constellation initiatives ventured into the “silver-lining” realm. Some speculated that the economic woes may provide even more incentive to invest in systems that will result in lower costs overall. One thinks of the drive to find “shovel ready” projects; perhaps it is timely to start funding “better shovels”?

What does this all mean for surveyors?
For the consumer and other low precision users, the multiple constellations may not have a great benefit beyond having a “backup” system. The value would be further diminished if these systems were not interoperable (let alone interchangeable) and even less valuable if there were fee structures for direct use or added as premium on the manufacture of the consumer units.

But for the surveyor the extra constellations may solve some of our biggest challenges, canopy, availability, time to fix, spacing of reference stations, and other solutions that may materialize as some more of these systems go online. What we have available to us is truly amazing with GPS alone, and GPS upgraded may solve many of these challenges on its own, but prepare to upgrade sometime in the future to take advantage of these changes. There are many other factors influencing error when we work in sub-centimeter precisions beyond that which multiple constellations may provide, just how much benefit this “constellation of constellations” can offset the inevitable higher costs remains to be seen. But it will be very interesting to find out.

Sidebar
In his mostly heavy-technical presentation to the ICG, Javad Ashjaee addressed a developer’s perspective on how to approach the integration of new constellations into design of new gear. His approach, similar to those touted by other manufacturers is to add “placeholder” (for lack of a better word) channels into the new gear with the hopes that these may be “activated” in some manner when those signals hit operational thresholds. While the Interface Control Document (ICD) documents (final operational specs that manufacturers would need to incorporate new signals) are yet to be made available for none but the two fully operational constellations, manufacturers have at least a skeletal view of the upcoming systems.

Just how much after-the-fact engineering and software development will be needed to integrate if/when the ICD’s become available is anyone’s guess, but Javad and others are pretty confident that they are well prepared.

The otherwise deeply technical presentation was punctuated by Javad pulling various elements of his new line of gear out of his pockets. The audience got a kick out of this and I noticed a few pleasantly startled looks when he revealed the little device that can fit under a hard hat for sub-foot resource mapping work. The presentation remained essentially informational and did not slide completely into a sales mode; this was after all an academic environment.

Later I did ask Javad about elements of his current strategy for the U.S. survey market, particularly about his offer of “pay-half-now-and-pay-half-later-when-business-picks-up”. He stated that part of his motivation was to offer something for the U.S. surveyors in this time of economic downturn as he feels that they have been very good to him in his various ventures and that as a U.S. citizen he also supports by running domestic production facilities.

I asked if some might abuse the terms of the unique financing arrangement he replied “Of course there will always be a few that do, some losses are always expected. The big department stores all anticipate a certain percentage of loss.” He went on to explain that all agreements are handled directly so that each situation can be evaluated quickly and that surveyors in general are an honorable group of folks.

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