Survey Perspectives – October 2007

October 25, 2007  - By 0 Comments

ION GNSS 2007 Report

I hope some of you had a chance to read my ION GNSS conference blog, as well as those of my fellow editors who attended the conference. I think Editor-in-Chief Alan Cameron’s brainstorm about this was very good, and I expect we will repeat next year. If you missed it, you can still view it on the GPS World Web site. It’s worth a few minutes of reading to get the flavor of what the hot issues were.

For this newsletter, I’m going to hit the highlights and comment on them, so fasten your seatbelt.

CGSIC  Meeting

Every year, the CGSIC (Civil GPS Service Interface Committee) holds two days of meetings before the ION GNSS conference; this year was no different. There were status briefings on the different programs, such as GPS and GPS modernization, GLONASS, Galileo, Compass, QZSS, WAAS/EGNOS, NDGPS and other activities. The CGSIC provides PDFs of the presentation on its site.

Satellite launch schedule. The GPS Wing plans to launch the rest of the IIR-Ms in FY08. One was launched last week, on October 17. Its designation will be PRN 15/SVN 55 when it’s declared operational in early November.

The next launch is scheduled for December. Then March 2008. Then June 2008. The launch schedule for the last one hasn’t been announced yet.

However, the GPS Wing said that they plan to launch the first Block IIF satellite (with L5 in addition to L2C) before they launch the last IIR-M. This will be interesting, because rumor has it that the Block IIF is waaaay behind schedule and has almost no chance of being ready in 2008.

Another interesting twist is that Lockheed was awarded a contract last Spring to enable a IIR-M satellite to broadcast an L5 test signal. Something about protecting the L5 frequency with the ITU (United Nations International Telecommunication Union) until the first IIF is ready.

GLONASS. For you GLONASS users (or potential ones), the future is brightening somewhat. I’ve been touting GLONASS for some time, and the reliability of operational satellites has been disappointing. One could say that this is due to the legacy satellites, which are averaging well under four years of operational life, but that isn’t the whole story. While the newer GLONASS-M satellites supposedly have a seven-year life guarantee, the track record for the GLONASS-M really isn’t that great. For example, of the three GLONASS-M satellites that were launched in December 2006, only one is operational today.

There are seventeen GLONASS satellites in orbit. Only eleven are operational. Seven are the newer GLONASS-M models and four are the legacy models.

The bright spot is that six more GLONASS-M satellites are scheduled to launch by the end of this year—three this month and three more in December. The number of usable GLONASS satellites really needs to improve. GLONASS can’t seem to get above 13 operational satellites, and many times it’s been down to 9. Don’t count on the six new satellites to be operational in the near future. Sometimes, it takes more than six months after launch for them to be declared operational. I wish it wasn’t the case, but that’s a fact. Sometimes, I beat up on the GPS Wing for their slow pace, but after they launch one, it’s operational within thirty days—and it’s reliable.

The GLONASS folks also announced that they are migrating the datum used by GLONASS, named PZ-90, to the ITRF (International Terrestrial Reference Frame). The revised GLONASS datum is named PZ-90.02. It was implemented on September 20, 2007.

It doesn’t match ITRF05 exactly, but I understand their intent is to do so eventually. They publish the PZ-90.02 difference from ITRF05 as:

Delta X: -36cm
Delta Y: +8cm
Delta Z: +18cm
There is no rotation.

Lastly, the long-awaited news about GLONASS possibly migrating to CDMA (to be compatible with GPS and Galileo specs) was discussed. The decision seems final (except the final government stamp) that GLONASS will eventually offer a CDMA signal interoperable with GPS L1 (called L1CR) and GPS L5 (called L5R). Not much else to mention on this now because it’s years—even a decade—away from now, but good news for users nonetheless.

Galileo. There’s a lot to write about this, but also nothing to write. As users, we would benefit tremendously from Galileo. But it’s time to quit talking and start doing. That’s not to say they haven’t been doing; hundreds of millions of dollars are being spent developing Galileo, but the same discussions about the benefits are becoming stale.

The biggest, and possibly best, news is that the European Union is not considering the PPP (Private-Public Partnership) funding model any longer. Looks like it will be a publicly financed system, at least into initial operation.

To borrow a slogan from Nike: Just Do It.

NDGPS. I blogged quite a bit about this during the conference.

Not much post-ION conference information on NDGPS. I see that the invitation for public comment on NDGPS is now closed. Last I checked, there were only about 42 public comments. I read through most of them; about 25 percent were not relevant. There were some very good comments in support of NDGPS.

NDGPS is probably going to survive in one form or another. I think it’s likely that some stations will stay and some will go away. If that’s the case and the USCG picks up the 12 they say they will, then the reduction in coverage will be minimal. The other possibility is that once the purse-string folks understand the cost of shutting down a site, that may be a big enough deterrent that the DOT finds the budget dollars somewhere to keep them going.

Satellite-Based Augmentation Systems (SBAS)

WAAS. Finally, long-term WAAS geo configuration is settled. The two legacy WAAS geos stopped broadcasting a couple of months ago. Right after the ION conference, the WAAS ground software was upgraded to incorporate the new reference stations in Canada and Mexico. WAAS users in Southern California, Southern Texas, Maine and Minnesota should see improved performance. The FAA GNSS program manager, Leo Eldridge, also stated that they are considering adding a third WAAS geo at 125W longitude, but that would be 3-4 years down the road.

EGNOS. The European Space Agency says EGNOS is in Initial Operations Phase (IOP) and expects it to enter Long-term Operations Phase (Safety-of-life, Commercial Services) in a couple of years. EGNOS is usable now and there are three broadcasting GEO satellites. See my July 2007 column for details.

The ESA reports that EGNOS coverage will expand northward, and eventually into Africa.

MSAS. MSAS was declared operational on September 27, 2007. There are two GEO satellites identified as PRN 129 and PRN 137; if your receiver doesn’t recognize them, check with the manufacturer for a firmware update. Ground users should be able to benefit from MSAS in a broad area including Australia. Here is a coverage map:

Map of two GEO satellites - PRN 129 and PRN 137

Industry Developments

Javad GNSS. Ever the GNSS maverick, Dr. Javad Ashjaee came to an agreement with Topcon, and now both companies are free to compete in all markets as of January 2008. Ashjaee has plenty of experience competing in survey/construction, so I would expect to see his company introducing products to that market next year.

Septentrio. It’s not often that you encounter a new designer of high-performance GNSS receivers. This little-known Belgian company might prove to be a factor in the GNSS market. They’ve positioned themselves as an OEM supplier, much like Novatel, so you probably won’t see their name on a product that you use, but they may make the guts of a product you use. They just opened a U.S. office in Los Angeles, California, that is run by the guy (Chris Litton) whose father (James Litton) founded NavCom Technology, a competitor of sorts. Weird.

NavCom Technology . NavCom is a wholly owned subsidiary of John Deere Company that has been focused on providing precision agriculture solutions for their owner. Now, that may be changing. They’ve hired two salespeople to develop external sales to achieve “NavCom’s revenue and growth goals for GPS products and services in direct sales, government customers, system integrators, and OEMs,” according to their press release.

Some of NavCom’s key engineers developed the first Leica survey receivers while at Magnavox, so they have the technical capability. But creating a better mousetrap in the survey/construction market isn’t necessarily the name of the game. They’ve got to have a solid dealer network, and that isn’t easy.

Leica/Novatel. No big surprise here: Leica (Hexagon) bought Novatel for $390M ($50/share). Novatel has been Leica’s sole source of GNSS technology for several years. If you bought Novatel stock five years ago for a couple of bucks a share, you did well. Also, the Topcon/Sokkia acquisition is still waiting for Japanese government approval, and with Novatel being Sokkia’s source of supply for GNSS technology, Sokkia is in a really weird position.

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GPS World staff

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