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  • GAARDIAN Consortium Wins GPS/eLoran Integrity Research Project

    A business and academic consortium led by Chronos Technology has received a major grant from the U.K. government sponsored Technology Strategy Board for a £2.2 million (approximately $3.3 million) research project to improve the safety and security of location-based applications such as marine navigation and road transportation.

    The consortium has dubbed the project GAARDIAN, or GNSS Availability, Accuracy, Reliability and Integrity Assessment for Timing and Navigation. Over the next 30 months, the consortium will be developing a system for mission and safety critical applications that will certify the accuracy, reliability, and integrity of positioning, navigation and timing systems, namely GPS, enhanced Loran (eLoran), and GLONASS.

    “GPS is fast becoming an unseen, embedded and low cost commodity. The challenge to the user community is that it may not appreciate the fact that subtle failures of the GPS signal could have disastrous or expensive consequences in mission or safety critical applications,” said Charles Curry, managing director of Chronos Technology. “The impact on GPS from threats such as jamming, spoofing, space-weather, multipath and other types of interference is likely to increase over the coming years due for example to easier availability of jamming technology or more esoteric phenomena such as increased sun-spot activity. The GAARDIAN project aims to create a data gathering system that will enable any user to monitor the health of the GPS signal in the vicinity of use on a 24-7 basis in real time.”

    GAARDIAN will use the Universal Time Coordinate-traceable timing signal from the GLAs’ eLoran station at Anthorn in Cumbria, United Kingdom, along with analysis of the GPS signal data to authenticate GPS reception wherever it is needed for mission and safety critical applications. The challenge is to gather and filter large volumes of GPS and eLoran data continuously in multiple, complex and disparate environments without losing content, according to Chronos.

    “This is an exciting project that will exploit the complementary benefits of satellite and terrestrial systems to reduce risk and so improve safety and security at sea and protection of the marine environment,” said Sally Basker, director of research and radionavigation for the General Lighthouse Authorities.

    The consortium brings together seven private, public, and academic organizations: Chronos Technology, BT Design, the General Lighthouse Authorities of the United Kingdom and Ireland, the Imperial College London, the (U.K.) National Physical Laboratory, the Ordnance Survey of Great Britain, and the University of Bath

  • Right Oblique . . . March!

    A complex base-mapping project spawns new techniques — and brings the power of oblique imagery to the military.

    By Art Kalinski, GISP

    When I started basic training and learned the marching command “right oblique march,” little did I know that the term “oblique” would become a capstone of my GIS career. As most readers know, I was a career naval officer who set up the Navy’s first GIS in the mid-eighties. After military retirement and graduate work at the University of North Carolina, I served as the Atlanta Regional Commission (ARC) GIS Manager until I retired early to join Pictometry last year.

    I did so because, much to my surprise, oblique imagery was not being used by the military. In Atlanta, we saw such a dramatic improvement in the effectiveness of first responders using oblique imagery that I felt compelled to help bring this technology to our troops in the field. The first major oblique imagery project that I managed was imaging all Marine Corps Bases in the continental United States.

    The United States Marine Corps contracted Pictometry International and the engineering firm PBS&J to image every USMC base in the continental U.S. with high-resolution ortho and oblique imagery. The imagery was captured from late 2007 through early 2008 and delivered to Marine Corps headquarters for installation in the East and West Coast GeoFidelis GIS systems. Capturing the imagery was uneventful, except for scheduling flights around base exercises and a solving a technical issue that was keeping us from shooting the high-altitude Marine Corps Mountain Warfare Training Center in Bridgeport, California.

    We assisted with the installation of the imagery and software at the East and West GeoFidelis computer centers in a CITRIX environment. After the installation, eighteen user-training classes were held at ten Marine Corps bases.

    Students in the USMC user-training classes learned about oblique imagery, the viewing software, and ESRI ArcGIS integration.
    Students in the USMC user-training classes learned about oblique imagery, the viewing software, and ESRI ArcGIS integration.

    The contract also called for a Public Works Implementation Plan and a Fire Protection Implementation Plan. Several other projects — including a 3D interactive model for security use, an oblique mosaic of a base to replace a large wall photograph lost in a major fire, and a proof of concept demonstrating the integration of oblique imagery with TerraGo GeoPDFs — were also completed.

    Quality Control

    I personally reviewed all the imagery for completeness of coverage, and individual images were spot-checked for image quality. The initial Quantico imagery had too much snow cover to be useful; it was reshot later in the season when the snow had melted. Snow obscures ground details, and the white reflections create excessive contrast that diminishes the visibility of adjoining features.

    All imagery from five directions — north, south, east, west, and ortho — had complete coverage, with the exception of the west view imagery of Miramar. Heavy winds had caused the aircraft to drift off course, resulting in a gap in the oblique imagery from the west view. The other views fully cover the two-square-mile area, and although this falls within quality standards, it will be reshot later this year. This is an error rate of only .02 percent.

    Technical Difficulties

    Oblique imagery had never been collected at the high altitudes needed to photograph the Mountain Warfare Training Center, located about 30 miles east of Yosemite Park. The problem was that the hard drives used to record the imagery couldn’t operate above 10,000 feet. Hard-disk magnetic recorders require a minimal air density in order to separate the record heads from the magnetic media with a microscopic air layer. Low air pressures at 14,000 feet cause the record heads to “crash,” or come in contact with the magnetic surface of the record media. Significant engineering time and experimentation ultimately solved the problem.

    The initial solution was to use pressurized rotating media with high-altitude specifications. This solution functions at up to approximately 16,000 feet above mean sea level, but is not fully reliable. The drives also have slower transfer rates, so more drives were needed in the aircraft for efficient capture. There are other limitations of the rotating technology that are not desirable for a long-term solution, but the capture was accomplished. Engineers are currently testing a more promising technology for high-altitude capture using high-speed, solid-state drive technology. Early examples of this technology proved to be too slow for efficient capture, but new versions of the equipment are showing more promise.

    There were concerns that a CITRIX deployment of the imagery and viewing software could have speed problems. Additionally, the Marine Corps is moving to ArcServer technology, so engineering time was devoted to alternative solutions. Engineers developed thin-client viewing software that could be used if needed.

    Something New: An Oblique Mosaic

    During the course of the contract, a feasibility question was raised: Was it possible to merge individual oblique images to create a base-wide oblique image? This idea was prompted by the loss, during a building fire, of a large traditional aerial photograph. Engineers developed a technique to tile and seamlessly merge multiple oblique photographs to form what looks like a single high-altitude — yet high-resolution — oblique image. This was especially challenging since oblique images don’t edge-match easily; each image has a different perspective, with each pixel being a different size and not rectangular in shape. Those challenges were overcome, and a single base-wide oblique image was created to replace the destroyed aerial photograph. Since the large mosaic was created from many low-altitude, high-resolution obliques, the final large oblique image had very fine resolution throughout.

    3D Models

    One of the deliverables requested under this contract was an interactive 3D model of a high-visibility location in the Washington D.C. area. The location presents security and logistics challenges, so an interactive 3D model will be very useful. The “wire frame” model was created from multiple oblique images by Precision Light Works (PLW) with a semi-automated process similar to stereo pair analysis.

    Once the wire frame is created, the same imagery is automatically draped on the 3D model to create not only a photo-realistic model, but a photo-accurate model — meaning that features are accurately located on the models. The 3D model created by PLW can be used in various software viewers, including Google Earth. Some 3D viewers can also do measurements within the 3D model.

    Public Works Report

    PBS&J worked with Pictometry engineers to develop an implementation plan using oblique imagery for public works applications. One public works application surfaced because there was a need to conduct a survey of runway approaches to determine whether trees had grown into the glide paths or if unauthorized construction had occurred within the glide paths.

    The traditional method to accomplish this task was with survey crews sighting and measuring objects on site — a time-consuming task. The ability to measure heights of vertical features made oblique imagery a natural choice for this application. PBS&J tested the concept and demonstrated the feasibility of doing surveys with the imagery, but more work will be needed to test the accuracy of this method and ultimately receive certification.

    Fire Protection and Emergency Response Report

    Another use of oblique imagery, which received significant publicity, is its use as a planning tool for firefighters en route to a fire. The imagery permits the firefighters to get the lay of the land, measure distances to fire hydrants, and view accessibility.
    Many counties using the oblique imagery have statistically measured a reduction in fire attack time of 60 to 90 seconds.

    This is a significant improvement, and the Marine Corps wanted to provide this advantage to their firefighters. The contract called for a firefighting implementation plan, and we had veteran Battalion Fire Chief Wayne Harper on our team to develop one. Paper reports have always left me cold, so I asked Harper, Why not deliver a functioning laptop, similar to those used by other firefighters, as a deliverable with the plan? We did exactly that, and delivered a fully functional Toughbook laptop configured with oblique imagery, GIS data, and software that could be used in fire trucks for tactical planning. This hands-on working example went further than just a paper report, and should facilitate the installation of similar capabilities on all USMC fire trucks.

    Taking the Lead

    Usually the Marine Corps is at the “tip of the spear” in world conflicts and combat situations, but rarely are they in the lead when it comes to technology. With this oblique imagery project, the USMC has certainly moved to the forefront with oblique imagery technology.

    Although not part of the Marine Corps contract, the development work done to complete the contract underpinned potential war fighter applications. The research and testing clearly points the way to make this technology available to deployed combat units in-theater in an operational mode that could provide near-real-time imagery to ground troops. To this end, Pictometry recently signed an alliance partnership with a leading defense contractor to work on a number of related military projects.

    Photos: Art Kalinski

     

  • Survey & Construction Newsletter, Early November 2008

    Questions from the Webinar:
    Is Dual-Frequency GPS — As We Know It — Becoming Obsolete?

    First of all, I’d like to thank everyone who attended my webinar a couple of weeks ago. I received many, many questions during the presentation and answered a few of these during the event, but there was no way I could handle them. But most were very good questions that deserve answers, so I’ve devoted this column to answering those I couldn’t address at the time.

    Oh yeah, kudos to you who attended; it was the most well-attended webinar to date for GPS World! I really enjoyed it and look forward to the next one in February or so of 2009. The focus on this last webinar was about the Department of Defense decision to discontinue supporting P(Y) on GPS L1 and L2 for civilian users after December 31, 2020.

    You can view the archived presentation here.

    Col. Mark Crews (ret.), former GPS Chief Engineer, is now retired but was kind enough to comment on some of the following questions that were submitted during the webinar, along with Don Jewell, GPS World’s Military and Government editor, and Richard Langley, the magazine’s Innovation editor.

    I should note that it has come to my attention that it is possible the U.S. government might be able to create a “work-around” before 2021 so that the Civil P(Y) sunset date becomes a non-issue. In other words, your legacy dual frequency GPS receivers may end up operating past December 31, 2020 without any problems. Be assured that I will stay on top of this issue and keep you (the readers) up-to-date on any changes regarding Civil P(Y) sunset.

    Question #1: Do you think that there will be a program to convert units to new technology like the television change to digital?

    Gakstatter: With respect to a government subsidy of sorts? I don’t believe there will be.

    Question #2: How do these codes affect the data gathered? And how is the new code going to differ?

    Gakstatter: I assume you’re referring to post-processing. L2C and L5 are completely new codes so more data is being collected. It really won’t affect that way you collect data in terms of the user interface. Length of data collection sessions will probably be shorter.

    A couple of years ago, I wrote an article about the benefit of the new codes. Some of the information in the article is dated now, but it is still fundamentally relevant. You can view the article here.

    Question #3: Explain how civilian receivers such as the Ashtech Z-12 tracks the P(Y) code.

    Gakstatter: I can’t speak specifically as to how Ashtech’s Z-Tracking technology works, but fundamentally I believe it reconstructs the full L2 carrier wavelength in addition to cross-correlating the P-code with L1 and L2.

    Question #4: How will this affect L1-only receivers using base corrections and getting RTK accuracy?

    Gakstatter: It won’t affect L1-only receivers.

    Question #5: Will the new codes be better under heavy canopy or forested areas?

    Gakstatter: L2C and L5 should improve operation in and around trees, but that’s not necessarily a good thing. Don’t be fooled into thinking you can operate reliably at the centimeter level under heavy tree canopy. That will never happen with only GPS. As I stated in the webinar, the real solution for that environment is the integration of other technologies such as pseudolites, inertial navigation, gyros, lasers, etc. I think those technologies will eventually be small and cheap enough to integrate into a GPS/GNSS receiver to allow seamless operation in GPS-impossible environments at the centimeter level.

    Also, more help than L2C and L5 would be the addition of more satellites via GLONASS and Galileo. In this case, I believe that quantity trumps quality. Yes, L2C and L5 are better, but it doesn’t matter how good they are if the receiver can’t track them because of obstructions.

    Question #6: Are these upgradeable or will we have to buy complete new equipment sets?

    Gakstatter: It depends on the product you have and the level of manufacturer support. If you recently purchased a GPS L1/L2 receiver, I would suspect the manufacturer will probably offer an upgrade to at least L2C without having to completely replace your receiver.

    If your L1/L2 is several years old and the manufacturer has discontinued support of that product, then the best you can hope for is some sort of trade-in credit towards the purchase of a new system.

    Question #7: Would a receiver that could track L1, L2, L2C, and L5 obtain a worse fix on just L2C and L5 alone?

    Gakstatter: I have no idea. In theory, it should perform better than the L1/L2 receivers of today because of better code structure, increased signal strength and better ability to mitigate ionospheric error. The frequency separation of L2 and L5 is not as great as that between L1 and L2 (or L5), so the dual-frequency iono correction potentially might not be quite as good. However, there won’t be enough satellites broadcasting L2C/L5 for at least another decade, so we won’t know until then!

    Question #8: Are receiver providers creating units that can be upgraded, or will we be looking at a complete setup replacement (as soon as we are using the stated three codes)?

    Gakstatter: Most major manufacturers of survey receivers have models that can track and use L2C, since that’s a signal that’s being broadcast today. Some say certain models are L5-ready. Likely, those will need to be tweaked with firmware when the actual L5 signal broadcasts.

    Question #9: Is there a simple-to-understand one page document that may explain all of this to a procurement agent so they know what to consider when purchasing GPS equipment? Does the same exist to pass onto engineers?

    Gakstatter: Hmmm … not that I know of, so I’ll try to create one. Email me in a month or so at [email protected].

    Question #10: Will this change have any effect on our equipment before 2010?

    Gakstatter: No. The semi-codeless sunset date is set for December 31, 2020. The only changes happening before 2010 are that a couple of more Block IIR-M satellites will be launched. The IIR-M broadcasts L2C in addition to L1 C/A. Also, in 2009 the first Block IIF satellite will be launched. The Block IIF will broadcast L2C and L5 in addition to L1 C/A.

    Question #11: Will there be new criteria for CORS?

    Gakstatter: The National Geodetic Service (NGS) is updating their GNSS strategy and moving toward supporting all broadcast signals (GPS and others). You may want to take a look at their five year and ten year plans.

    Question #12: Is there likely to be a gradual degradation in the L2 signal availability in the years approaching the sunset date as the older satellites are lost from the system and replaced by the newer birds?

    Gakstatter: I defer to the GPS World’s military and government editor Don Jewell and retired GPS Chief Engineer Col. Mark Crews (ret.). Both say there will be no degradation of the L2 signal, gradual or otherwise.

    Question #13: I had read an article that basically stated more frequencies would yield higher accuracies, especially vertical, over more satellites. Is this an accurate statement?

    Gakstatter: I don’t believe just adding more signals to the same number of satellites will significantly improve accuracy. I believe that more satellites (thus improved satellite geometry) is the best way to improve accuracy, especially vertical. With a full constellation of GPS, GLONASS and Galileo, the number of satellites in view and the PDOP numbers would be incredibly good for high precision users.

    Comment from Dr. Richard Langley, Editor of GPS World’s Innovation column:

    Recall that delta-subscript v = VDOP x delta-subscript p where delta-subscript p is the measurement accuracy (pseudorange or carrier phase), if we can reduce delta-subscript p, then we can also reduce delta-subscript v. So yes, reducing VDOP with more satellites will help more but improvements in signal structure and receiver technology will also help. L5 signals, for example, should have lower multipath contamination and also less noise at low elevation angles.

    Question #14: Why does L5 require a new antenna?

    Gakstatter: It is broadcast on a significantly different frequency (1176.4 5Mhz) than L1 (1575.42 Mhz) and L2 (1227.60 Mhz).

    Question #15: What effect will this have on static processed data?

    Gakstatter: None with respect to the user interface. Behind the scenes, more data is collected and the algorithms of the post-processing software will change significantly. You may see a slight improvement in accuracy. .

    Question #16: So how do you make yourself ready?

    Gakstatter: I’ll be writing more about this in the future. Like I said in my webinar, twelve years from now is a long time. There is no rush to take action.

    Question #17: With reference to my last question (Question #13), presumably no more L2 birds are being launched in the future; what is their expected lifespan?

    Gakstatter: All planned GPS satellites include L2. It’s important to note that L2 isn’t being rendered obsolete. The government is simply reserving the right to change P(Y) on L2 which was originally designed for the military.

    L2C code is the future of L2 for civilian users.

    Question #18: Do you expect the government/public/DOT VRS CORS systems to be upgraded and established with L2C and/or L5 by the sunset date for the L1/L2 signal?

    Gakstatter: I’d refer you to the NGS 10 year plan with respect to CORS. Otherwise, it is up to each individual public or private network (RTK or otherwise) to ensure their network is prepared to handle the sunset date of December 31, 2020.

    Question #19: Let’s say I have my semi-codeless system L1/L2 and everything is fine on January. 1, 2021, but on January 2, 2021 I have an issue. What’s my alternative at that point?

    Gakstatter: You might be able to use L1-only for post-processing, but you may even have an issue with that.

    Question #20: If not planning to already, let listeners know what to spec now in new purchases to ensure equipment will work past 2020.

    Gakstatter: I will work on that.

    Question #21: Do antennas (ex. Trimble Zephyr) become obsolete, or just the receiver board itself? Or do both components become obsolete?

    Gakstatter: It depends on which Zephyr model you are referring to. The newest Zephyr 2 supports:

    • GPS: L1, L2, L5
    • GLONASS: L1, L2, L3
    • Galileo: E1, E2, E5, E6

    This antenna will not be affected. In fact, all GPS dual-frequency antennas of today will be fine in tracking L1 and L2C. Only if you desire to utilize L5 might you need a new antenna.

    Question #22: What happens to the old satellites? Do they just burn up as their orbit degrades and they approach earth?

    Gakstatter: I deferred to the GPS World’s military and government editor Don Jewell and retired GPS Chief Engineer Col. Mark Crews (ret.):

    There are definitely some people who believe that we should de-orbit all our satellites, but unless the satellite is just a few hundred miles above us in a Low Earth Orbit (LEO), it is simply not possible. The GPS satellites orbit in the Medium Earth Orbit (MEO) regime which is 20,200 kilometers (~12,000 miles), on average, above the surface of the Earth. When a satellite becomes too old or fails for some reason, it is boosted into a slightly higher orbit plane which puts it out of the way of any operational GPS satellites.

    In recent years, through solid engineering and strategic thinking, some of the GPS satellites that were still functional, but would have normally been boosted up to a higher orbit, have been left in the operational MEO orbit plane and put to sleep or in standby mode for future use. Just recently some of these older GPS satellites have been reactivated. If we were to allow the satellites orbit to naturally decay from MEO, we will have been in our graves for thousands of years by the time they reach the Earth’s atmosphere, where they would burn-up on reentry.

    Further comment from Dr. Richard Langley:

    There is also the potential for collisions of dead satellites from different constellations (GPS, GLONASS, Galileo, etc.) as a result of the satellites drifting out of their assigned orbit bands over the next 100 years or so. The GLONASS folks are studying this and it was mentioned during Sergey Revnivykh’s presentation at the ION GNSS 2008 CGSIC meeting.

    Question #23: Are there receivers on the market now anticipating the change?

    Gakstatter: Yes, there are many survey receivers on the market right now that can utilize L2C and are prepared for L5. They are typically the premium-priced receivers offered by the manufacturers.

    Question #24: Can you give a brand/model example of a GIS sub-foot receiver that might be affected?

    Gakstatter: Trimble GeoXH, ProXH.

    Question #25: Will L1 receivers using real time reference networks (e.g. Trimble GNSS VRS) be affected?

    Gakstatter: I don’t believe there will be any affect.

    Question #26: How will the CORS network be affected?

    Gakstatter: Please refer to the NGS 10 year plan. I believe the NGS is preparing well for the transition. However, NGS doesn’t have control over most of the CORS stations. That’s a different story.

    Question #27: Can you talk in general about accuracy comparison of the new L2C and L5 capabilities with current legacy RTK accuracy? Will we still need base stations?

    Gakstatter: I touched on this in the webinar a bit. I don’t believe you’ll see a substantial increase in accuracy. I think you’ll see a substantial increase in reliability and robustness of the positions.

    The way to achieve greater accuracy (vertical in particular) is more observations (eg. GLONASS and Galileo).

    Question #28: Would GPS World plan on researching GPS manufacturers and their products that DO NOT support L2C at this time? We sell NovAtel OEMV and they have L2C, but what about the OEM4 we sold two years ago? An article on this would be nice as I can’t find it on their spec sheet.

    Gakstatter: I think this is a good idea and the subject has been raised before. I’m not sure when it will happen, but I believe I will do something along these lines.

    Question #29: Do you have any recommendations for a small startup land survey company? Wait for the new technology to come out or purchase what’s out there now?

    Gakstatter: Well, I think it’s more of a business issue than a technology issue. I’ll make a bunch of assumptions when answering. Personally, I’d try to keep your capital investment as low as possible at this point.

    If you only need post-processing, then a pair of L1-only static receivers is a relatively small investment (well under $10,000). Or, one GPS dual frequency receiver will do, and use an online positioning service like OPUS.

    If you need RTK (real-time, centimeter-level positioning for staking/topo), then the price tag goes up. Do you have access to an RTK network? If so, then you only need an RTK rover and a data plan from a wireless provider like Sprint, AT&T, T-Mobile, etc.

    If you need RTK and no RTK Network access, then you’ll need a RTK reference station also. Again, the price tag goes up. Another piece of equipment to consider (maybe in lieu of GPS) would be a robotic total station.

    It all depends on what kind of projects your company will be involved in the majority of the time.

    Question #30: Comment: GPS tech changes significantly every 1.5 to 2 years, while the useful lifetime of a receiver is on the order of 6 to 8 years. Proper planning will make this a non-issue.

    Gakstatter: In general, I agree there’s plenty of time to plan for the transition. However, the fact is that some GPS equipment purchased in the early 1990’s is still working today and some legacy equipment purchased today will still be operating twelve years from now. This is especially true for survey receivers because the price tag is so high.

    Question #31: Will my L1/L2 receivers still be able to collect L1 data for static computations?

    Gakstatter: I believe they will, but caveat emptor.

    Question #32: If I upgrade to L2C and not L5, what will my limitations be?

    Gakstatter: You will be no worse off than you are today.

    Question #33: Can we expect an increase in vertical positioning accuracy with the new L2C and L5 frequencies?

    Gakstatter: I don’t believe so. For better vertical accuracy, the best bang for your buck will be more satellites (eg. GLONASS, Galileo). However, as stated in the answer to Question #13, there will be some gain in accuracy due to improvements in the code structure of both L2C and L5.

    Question #34: Are the new satellites capable of maintaining our legacy signals, or is it totally out of the question?

    Gakstatter: It’s not that the government wants to eliminate any signals, but rather they reserve the right to alter the military P(Y) signal on L2. After December 31, 2020, it may behave just like it does today or it may not, so yes, they do have the capability to have the satellites behave as they do today.

    Question #35: Comment: I’m like your friend who expected his last purchase to carry him through to retirement. The way my retirement account is growing (negatively) I may still be carrying a range rod when this change occurs.

    Gakstatter: I empathize. Maybe I’ll join you.

    Question #36: will we still need two receivers to use RTK techniques?

    Gakstatter: I also talked about this question during the webinar a bit. Yes, there will still be a need, but I think it will be more ubiquitous than it is today, primarily because of the proliferation of RTK networks and wireless communications technology. Because of this, I think you’ll see the need to operate your own RTK reference station diminishes significantly.

    Question #37: How will this affect my processing software, such as Ashtech Office?

    Gakstatter: Well, you’ll be okay until December 31, 2020. If there is an upgrade path that supports L2C, that might be a good move if your receiver supports L2C.

    Question #38: How much will it cost, upgrading to L5?

    Gakstatter: Please check with your local dealer or the manufacturer of your equipment.

    Question #39: Does adding L1C into the mix have a great advantage?

    Gakstatter: With respect to interoperability with Galileo, yes. With respect to the L1C code itself, it will be superior to its predecessor, L1 C/A, much like L2C/L5 and offer enhanced code and carrier tracking.

    Question #40: With L2C only (no L5), is the cross correlation with the L1 C/A or will there be a new code on L1 as well?

    Gakstatter: There is no new code on L1 at present. The two civilian codes are L1 C/A (the original) and L2C. On Block III GPS satellites, L1C is planned. Basically, a new and improved L1 C/A.

    Question #41: How much is the difference between maintaining the legacy signals and not maintaining the signals?

    Gakstatter: Again, I deferred to the GPS World’s military and government editor Don Jewell and retired GPS Chief Engineer Col. Mark Crews (ret.):

    I assume you are talking about the difference in costs here, but this is really not a question pertinent to this issue, as we are currently not planning on doing away with any current signals. Both the L1 and the L2 signal structure, coded and codeless, will still be broadcast for the foreseeable future. The issue is that, after December 31, 2020, the flex-power capability may cause temporary problems in codeless and semi-codeless civilian receivers for periods of time while the satellites are in flex-power mode.

    However, your question is pertinent in the general sense, as there are new GPS signals and frequencies coming on-board and there are those who believe that some of the old signal structures should be abandoned for the newer more capable signals. So far there have been no decisions made to abandon any of the current signals, only to make them stronger and more robust, with more anti-jam and anti-interference capabilities, which is one of the functions of flex-power that serves the war fighter.

    There is also the possibility that flexible power mode will be modified by 2021 in such a way that it will not cause a L2 phase shift and affect civilian receivers that are using semi-codeless techniques.

    Question #42: Is there a minimum baseline requirement for differential processing (RTK or otherwise) with dual frequency receivers? Will the change from L1/L2 to L1/L5 alter this?

    Gakstatter: The minimum baseline won’t change. There really isn’t one for dual frequency GPS ,although very short baselines sometimes fare better with L1-only rather than L1/L2.

    With regard to legacy L1/L2 vs. L1/L2C/L5, I believe you’ll have more robust solutions with the latter, and longer baseline processing will be enhanced.

    Question #43: If we need dual frequency receivers for survey quality, wouldn’t three frequencies enhance ambiguity resolution and/or accuracy and precision?

    Gakstatter: I believe ambiguity resolution will be enhanced (e.g. quicker and more reliable) due to better ionospheric correction with three frequencies. With regards to accuracy, I don’t see a significant improvement. As I mentioned before, the best way to enhance accuracy/precision (especially vertical) is signals from more satellites (e.g. GLONASS, Galileo, or GPS).

    Question #44: After the sunset date will dual frequency not work at all, or just give bad data? How will we know if the signal has changed?

    Gakstatter: Your receiver won’t be able to correctly resolve the integer ambiguity because of the phase shift. You won’t know until it happens. It’s not a permanent state either. Legacy receivers may work just fine for periods of time, but then may not for periods of time.

    Referring back to the answer to Question #41, it is also possible that the US Government will find a way to resolve this situation where we will not see a phase shift at all.

    Question #45: Will this enhance my L1 handheld accuracy at all?

    Gakstatter: No. L1 C/A will remain the same.

    Question #46: Comment: I know several surveyors who need to hear this conference. It was great. Please publish on the ‘net for access or email to us for distribution. Thank you.

    Gakstatter: Thanks for listening and taking the time to comment. Pls feel free to forward this email or the links embedded in this email to those whom you think are interested. You can take in the webinar via the archived version here.

    If I didn’t fully answer your questions or if it spawned more, please don’t hesitate to email me more questions and comments.

  • AeroScout Debuts GPS/Wi-Fi Tracking at U.S. Air Base

    AeroScout Inc. has unveiled a combination GPS and Wi-Fi asset management system that has been selected by the U.S. Air Force 309th Aerospace Maintenance and Regeneration Group (AMARG) for its 110 million-square-foot outdoor facility at the Davis-Monthan Air Force Base in Arizona.

    The system includes battery-powered tags that use both GPS to determine location outdoors and Wi-Fi to transport asset location and other information over a customer’s network, according to AeroScout.

    The large-scale deployment will initially include 1,000 AeroScout GPS Wi-Fi tags for essential support equipment. The 309th AMARG stores thousands of aircraft and aircraft parts at the outdoor facility at Davis-Monthan outside Tucson, Arizona. In addition to tracking the precise location of essential support equipment, the AerosScout system will provide automated inventory reports, the company said.

    The system will leverage the facility’s existing Wi-Fi network and 42 access points with high-gain antennas, which are also used for data communication. Using AeroScout’s MobileView 4.0 software, staff will be able to search for, locate, and manage essential equipment, according to the company.

  • GEOINT Transitions to the Future

    By Art Kalinski, GISP

    Attending the GEOINT 2008 conference was like drinking from a fire hose: too many superb sessions by top leaders in the field, and more than 120 exhibitors on the show floor. In a short amount of time, this community has transformed itself. Just three years ago there were many contractors offering data and imagery, but very little in the way of integration and analysis tools. This year almost all efforts were pointed toward integration, with fast evaluation and response.

    Keynote speaker Retired Air Force Lt .Gen. James R. Clapper, Jr.
    Keynote speaker Retired Air Force Lt .Gen. James R. Clapper, Jr.

    The opening session keynote speaker was the current Undersecretary of Defense for Intelligence, retired Air Force Lt .Gen. James R. Clapper, Jr. He addressed the need for integration of intel sources and explained how difficult it is to achieve, because of security concerns about sharing data among agencies and coalition forces. He expressed apprehension about managing the flood of data — how will we sort out meaningful information from the torrent? Clapper discussed the growing uneasiness over our vulnerability to cyber attacks, and noted that new developments in biometrics make identification of terrorists easier, but complicate the ability of our forces to infiltrate hostile groups.

    General Clapper then compared the Cold War, which presented us with an enemy that was static and predictable, with the irregular warfare of today. Gone is the old environment that permitted the intel community to take days to identify and evaluate threats; now we must identify threats in mere hours by observing patterns of life and individual behavior. Clapper stated that we have become very good at precise attacks, but we still have a long way to go to prevent attacks.

    Integration on Display

    In the exhibit hall there were countless examples of improvements to existing technology, with many efforts toward data integration. There were also a few new developments on display.

    Image_003
    BAE Systems created a significant buzz — including strong mention by another keynote speaker, Maj. Gen. John M. Custer — with its new SOCET GXP system. The system grew out of SOCET SET and breaks down the wall between image analysis and geospatial analysis to an environment that the company calls Extreme Analysis. It combines imagery, geo data, metadata, attributes, and analysis tools into one unified package.

    Image_004Lockheed Martin demonstrated a very interesting capability. Starting with 3D models created by PLW with Pictometry imagery, Lockheed transforms the models with complex algorithms to reflect night-time views or varying weather conditions, with very realistic results.

    Speaking of Lockheed, the aerospace company used the conference to announce that it has signed an agreement to collaborate with Pictometry. The two companies will develop next-generation visualization tools for both domestic applications and in-theater, near-real time oblique imaging and 3D model creation using manned and unmanned aircraft.

    FortiusOne demonstrated its Web-based service that bridges GIS and GeoWeb services with very user-friendly tools that access a huge global database of coverage designed for non-GIS-trained users. The Web service not only permits the viewing of maps and data, it also allows viewers to add their own data. One example was flood maps that could be enhanced with local data and then saved as printed documents or PDFs.

    I also saw a demonstration of Zebra Technologies’ holographic video table, which displays full-motion video as a 3D hologram similar to the still holograms that Zebra has previously developed. While viewing the holodeck-style platform, I half-expected to see Princess Leia appear and ask for help. The technology is still a long way from prime time, but it was amazing to see full-motion video as a hologram.

    Getting Results

    The most impressive keynote session was given by Maj. Gen. John M. Custer, Commander of the U.S. Army Intelligence Center at Ft. Huachuca. He was probably the most passionate speaker, and clearly had a sense of urgency about his mission. He heads the intel training efforts for the U.S. Army, and described how they transformed training of intel people to be as realistic as possible so that soldiers leaving the training can hit the ground running.

    General Custer addresses the crowd during his keynote speech.

    That’s one thing about military training that impressed me early in my career: they have to get results. You can’t pretend to get a ship under way, you have to actually do it on schedule. You can’t philosophize about getting rounds on target, you have to actually do it. Having an education background, I was completely dumbfounded when I joined the Navy and saw 19-year-old kids do more effective teaching than I had experienced in high school and college. There is no better example than the work done at Ft. Huachuca.

    General Custer played a very fast-paced video showing the results; it depicted intel specialists in the field supporting their own unit under fire. They were receiving intel from many sources — satellite imagery, database from interrogations, intercepted communications, aerial imagery, down-linked video, and video from field robots in hostile fire locations — all of which were integrated and analyzed into actionable intelligence that saves lives and accomplishes the mission.

    Getting there was not easy, and the General had to overcome many hurdles, including getting live data feeds so the soldiers could train on current, real-life data. Custer’s goal was to have a training environment that was absolutely indistinguishable from the actual combat environment. He indicated that all tools are moving from thick clients to thin clients and that UAVs are playing and increasing roll in the battlefield. Brigades will be working with up to 32 UAVs, with 18 of them in the air. As a result, their data centers will be dealing with petabytes of data. Custer cited an interesting statistic he developed. He observed that in each war cycle since WWII the number of troops was only 10 percent of the previous war, but the needed data bandwidth increased 100-fold.

    The video was powerful, and Custer shared how he had personally presented the flag at over 25 military funerals to grieving widows and parents — a life-changing event. I can tell you from personal experience that he is absolutely correct. It’s one thing to attend a funeral of someone that has lived a long and fulfilling life. It’s totally different to see very young children standing in front of the boots and helmet, knowing that they will never know their dad who died for his brothers and to keep the rest of us safe. General Custer received the longest, strongest standing ovation that I’ve seen in years.

    As I looked around at the crowd I reminded myself that these are the people that have been instrumental in preventing another major attack on this county. I was reminded of the Irish Republican Army after a thwarted bombing of 10 Downing Street. The spokesman was quoted saying that Scotland Yard was lucky this time, but the Yard will have to be lucky every time — and the IRA will only have to be lucky once. I’m hoping that with everyone’s hard work we will make our own luck.

  • More Data Formats, LizardTech Support Among EarthWhere 4.3 Updates

    SPADAC has launched version 4.3 of EarthWhere, its spatial data management product that provides streamlined, enterprise-wide access to geospatial data, according to the company.

    Since SPADAC’s acquisition of EarthWhere in 2007 from SANZ, a former provider of data storage and data management solutions, SPADAC’s product development group has worked to enhance the product and provide technical support to its EarthWhere customers, reportedly resulting in a 79 percent growth in customer product implementations.

    “We work closely with customers to identify product enhancements and new functions that will improve their organization’s ability to more quickly and effectively ingest, catalog, explore, and provision data,” said Peter Borissow, SPADAC product manager for EarthWhere. “The added benefits now available to customers through EarthWhere 4.3 are a great example of this, and we’re already planning to make several more optional modules available over the next six months.”

    Updates in EarthWhere 4.3 include:

    • additional data formats, including Landsat TM/ETM+ in NLAPS format, FORMOSAT-2, and WorldView-1. Version 4.3 also adds more than 200 HARN projections to support customers using aerial-based imagery, according to the company.
    • ActiveIngest, a task-based ingestion engine, received a Java-based graphical user interface that provides enhanced reporting statistics, cross-platform support, and progress status.
    • an administrative option that facilitates the movement and relocation of source data files and a new tool that helps users find and delete duplicate data source entries.
    • a new one-click installer for free installations and upgrades through two packages that wrap all third party dependencies and the core base install.
    • an optional LizardTech module that provides the capability to output data products in MrSID (MG2/MG3) or JPEG 2000 format for an additional cost. The EarthWhere base product currently supports only reading and cataloging of MrSID (MG2/MG3) or JPEG 2000 format.

  • Webinar: Is Dual-Frequency GPS – As We Know It – Becoming Obsolete?

    On October 28 GPS World survey and construction Editor Eric Gakstatter will be discussing the U.S. Department of Defense GPS Wing’s proposal to discontinue supporting Civil P(Y) semi-codeless on GPS L1 and L2 after December 31, 2020 — rendering a massive amount of high-precision GPS equipment obsolete. The webinar is hosted by GPS World and sponsored by Magellan GPS.

    What You’ll Learn:

    • A discussion of the semi-codeless technique they are referring to.
    • Who’s affected.
    • Which receivers are affected.
    • How it might impact your organization.
    • What options you have if you own legacy dual-frequency GPS equipment.

    Who Should Attend:

    The seminar will be targeted to professionals in high-precision positioning:

    • Land surveying
    • Aerial surveying
    • Hydrography
    • Exploration
    • Geodesy
    • Photogrammetry/remote sensing
    • Construction
    • Mining
    • Civil engineering
    • Natural resource management
    • Cartography/mapmaking
    • Utilities/public works
    • Environmental management
    • High precision guidance in aviation
    • Military and government

  • Puzzling Over PDFs

    By Art Kalinski, GISP

    GeoPDFs have become a very valuable tool for the GIS community, but it has been a slow evolution. My first exposure to GeoPDFs came about five years ago, when I saw a new GIS map-publishing medium offered by Layton Graphics. The local Atlanta firm started out as a microfilm copy specialist, then slowly moved into digital media. While I was in the GIS shop at the Atlanta Regional Commission (ARC), I would occasionally get a visit from one of their salespeople, but they really didn’t have anything we needed.

    As time progressed, Layton Graphics evolved further into digital publishing, and eventually into the Adobe Acrobat format. I continued to get an occasional visit, and I always gave them 10 minutes of my time. As the years progressed, however, I grew in age and my patience shrunk proportionately, so when I received a visit from them again in 2003 I barely gave them three minutes.

    But to quote my uncle, “Eventually even a blind pig will find an acorn.” The sales rep showed me a new Layton Graphics product based on Adobe technology — and it fit a real need perfectly. For the first time, my perfunctory meeting grew into two hours as I invited more and more ARC staff members to sit in on this new product demo.

    What Layton Graphics — now known as TerraGo Technologies — had created was the GeoPDF format, plus tools that manipulated the files in Adobe Reader. It was a brilliant new geospatial publishing medium. For those of you who are not familiar with TerraGo, let me explain the features that caught my attention.

    For years, we published our ARC GIS data on CDs (primarily as Shapefiles) and included a copy of ArcExplorer for those users who didn’t have a GIS. The problem with providing raw GIS data to inexperienced users is that it typically resulted in cartographically poor maps, many of which were truly terrible.

    ESRI’s Map Publisher partially solved that problem by permitting the creation of a GIS-based map as an MDF, which retained the original cartography of the publisher. The only problem was that the user had to download Map Reader, the MDF, and all the GIS data layers. Additionally, if there was a problem with Map Reader pointing to any of the data, the map would not print. Some of those problems were solved in later versions, but it is still not as elegant a solution as TerraGo’s: a single file viewable in Adobe Reader.

    In ESRI’s ArcGIS, users create maps using the data layers, colors, and symbology of their choice. When the GeoPDF is created using TerraGo Publisher (previously known as Map2PDF), the desired “look” will be maintained, but it won’t be a dumb map; the file is actually a self-contained GIS viewing environment. Users can zoom in and out, pan, and — using the table of contents to the left of the map view — turn layers on and off. There is even a query tool that permits the display of attributes as users click on the geographic features. The map layers can be GIS vector data or background ortho imagery. All these manipulations can be performed using the ubiquitous, free Acrobat Reader from Adobe.

    The thing that makes the GeoPDF so remarkable is that the GIS map layout, and all GIS data, travels as one single file: no lost or mis-pointed data! It’s foolproof for the receiver, and is very intuitive even for users not trained in GIS.

    But it doesn’t end there if the receiver is willing to download TerraGo Desktop, a free collection of even more sophisticated tools. The solution, which until recently was known as the GeoPDF Toolbar, offers users the ability to publish and collaborate on the same GeoPDF file via the Internet (annotations created on the map are viewable by all linked viewers). They can also measure distance, area, and direction, and view vehicle locations if GPS tracking data is available.

    This interactive collaboration capability really got my attention for homeland security and first-responder applications, especially in mutual aid situations. Just imagine creating a compact GIS project of a disaster location, then quickly sending the single GeoPDF to anyone responding, even those who are unfamiliar with the area or with GIS software. The annotations can be saved as Shapefiles, which makes the GeoPDF an ideal data collection environment.

    TerraGo designed the GeoPDF format with an extensive capability to store and catalog large and complex datasets. That’s one reason why the Army Corps of Engineers has published its entire collection of world maps as GeoPDF files. The National Geospatial-Intelligence Agency is another federal user taking advantage of the format.

    Discerning Differences

    There has been a Kabuki dance going on between TerraGo, ESRI, and Adobe as they try not to step on each other’s intellectual-property toes. TerraGo and Adobe worked together to get GeoPDF support in Adobe Reader. Adobe and ESRI partnered to extend the ISO 3200 specifications for PDFs to include geospatial. In the meantime, TerraGo is creating GeoPDFs from ArcMap and ESRI is creating PDFs with the proposed geospatial extension to ISO 32000.

    Now that TerraGo isn’t the only option anymore, the question for many of us is, What’s the difference between TerraGo’s GeoPDFs and geospatial PDFs created by ESRI software? For simple map creation, the answer is: not much. The Adobe solution and the TerraGo solution are very similar now that TerraGo has signed an alliance agreement with Adobe.

    By opening the door, TerraGo hopes to reach many more users to promote the added functionality of their Desktop tools. Specifically, the added functionality enables users to perform the following tasks:

    • Use drawing tools to mark up maps and collaborate between users in remote locations. The remote users don’t need GIS software or special training.
    • Convert the mark-up graphics to GIS data. This makes a GeoPDF a very simple, low-cost field GIS data collection tool. There’s no need for additional GIS licenses to do simple field data collection. This same capability permits the export of the data as Shapefiles or KML files.
    • Create complex linked collections of maps as map books, or combine many maps into a large mosaic.
    • Retain and enable hyperlinks to other documents, files, and HTML sites.
    • Display AVL (automatic vehicle locator) GPS data to show the movement of vehicles on the GeoPDF map.

    In addition, according to users of both types of files, many of the common capabilities seem to be more robust and work better in the TerraGo environment. For example, there are more problems selecting attributes in an Acrobat map than in a TerraGo GeoPDF. TerraGo has had years of experience to refine its solution and create more robust, reliable tools.

    The simple conclusion is that both options perform the key job of creating cartographically sound maps in a GIS viewing environment. Both are georeferenced. Both provide attribute query. Both provide the ability to turn layers on and off, pan, zoom, measure distances, and obtain coordinates. The subtle differences only become noticeable as you use both solutions. Whether you require the additional capabilities of a TerraGo GeoPDF — such as the collaboration and Shapefile creation — will ultimately depend on your needs.

  • Survey & Construction Newsletter, Late October 2008

    Well, if the economy is going to tank …

    … at least our industry outlook is pretty good for the next five years. Hmmm … I guess I should clarify, because the survey/construction business is clearly slowing here in the United States (I probably don’t need to tell you that). But, if you want to look at a bright spot through all of the gloom and doom of today’s global economy, the GNSS industry is looking really good for the next five years.

    Ok, I first need to apologize in advance for the shameless self-promotion, kind of. I co-authored a market research report on high precision GNSS which we just completed. The report covers the period 2008-2012 and discusses market growth, technology, trends, etc. for only high-precision (10cm or less) GNSS. Not just receivers themselves, but associated services such as augmentation (RTK Networks), distribution (dealers) and others.

    Just in the course of writing this column twice a month, I often find myself humbled when writing about GNSS issues. The “more I learn, the more I learn how little I know” cliché really applies here. Authoring the report was no different and perhaps even more challenging because of its 214-page length and breadth of topics covered. It really opens one’s eyes as to how far GNSS has weaved its way into our lives and, even more enlightening, how far it still has to go.

    Another thought: I just received an email from the people upstairs asking for bullet points to take to the budget meetings in hammering out the 2009 GPS World magazine budget. I really started thinking to myself; GNSS is one of the few industries I can think of that, even in a horrible global economy, is still going to experience growth over the next five years. We are fortunate indeed. Seriously, think of the executive running Starbucks. Imagine their forecasts for 2009? The first place people will look is to save is that $4 per day.

    Looking at the hard numbers, the global value of GNSS goods and services in 2008 will end up being approximately $3 billion (all figures are in U.S. dollars). It’s predicted that it will grow to $6 billion to $8 billion by 2012. $6 billion is realistic growth, assuming a global economic downturn and softening of some commodity prices, which is already happening. A particularly bright spot is the robust agriculture market, where there is renewed growth in precision agriculture for GNSS, primarily in high-end RTK applications.

    Looking at the above graphic, the compound annual growth rate (CAGR) in a realistic or expected scenario is 19 percent, while the optimistic CAGR is 23 percent. A significant portion of that growth is driven by widespread adoption of GNSS as a productivity tool. GNSS is transforming from a niche tool used in niche industries to an essential productivity tool in global industry sectors such as mining, agriculture and construction.

    Breaking the growth down further, the traditional GNSS markets you are familiar with will experience the slowest growth: 16 percent to 21 percent CAGR. That’s to be expected given the steady adoption rate over the last twenty years.

    Machine control applications will experience a growth of 23 percent to 28 percent CAGR. This isn’t a big surprise, as you’ve probably experienced the adoption of this technology in your daily work if you haven’t been involved with it yourself.

    The highest growth area will be precision GNSS data services with a CAGR of 33 percent to 38 percent. This includes the GNSS reference station infrastructure and wireless communications needed to deliver data services over a region, such as with RTK networks and RTK clusters. Technology innovation and development will enable precise positioning with less complexity and lower cost, thus encouraging adoption and stimulating growth.

    The steady shift in user demographics, continued evolution of space-based systems and precise positioning techniques combined with the growth of dedicated precision GNSS infrastructure and associated services are a recipe for a dynamic and rapidly changing business environment.

    So, if you’re looking for a bright light in the darkness of global financial instability, GNSS is one to talk about – and you’re right in the middle of it.

    If you want to read more about the report, there’s a 20-page abstract you can download from GPS World’s site by clicking here. You’ll have to fill out a short form in order to download the PDF, but the price is right, as in free.

    Back to the Subject of Solar Activity

    This is one of the more humbling subjects I’ve written about. As I mention above, as much as I write and try to stay on top of subjects, I seem to be a step behind at times. Fortunately, readers offer their help in times of need.

    John Sumption from Colorado commented on my last column regarding solar activity. He opined:

    It’s well worth noting that Solar Cycle 24 has not lived up to any of its advanced billing. In fact, so far, it’s been quite a dud.

    A maximum in 2011 is now virtually impossible. A maximum in 2012 is unlikely. The 11-year solar cycle usually comprises four years of rise time to maximum, and seven years of fall time to minimum. Solar Cycle 23 maximum was in 2000. It has already been eight years of fall time, and Solar Cycle 24 has so far been anemic at best. Yesterday and today a couple very small sunspecks appeared, too small and insignificant to be officially counted, and they have already faded to invisibility.

    There is active discussion across the blogosphere about Solar Cycles 23 and 24 and the possible implications. The official NOAA/NASA panel predictions you mention are expected to be “updated annually” as they say on the website. In conjunction with a Space Weather Workshop in May, the panel simply reiterated its predictions, there being insufficient data on which to base a significant change.

    As you know the panel originally issued a split decision; six of the panelists predicting larger than normal, six predicting smaller. The lack of Solar Cycle 24 activity continues to outpace the official predictions, and so far, even the six low-side forecasters seem to have overestimated Cycle 24.

    An updated prediction from this group should not be expected before Spring 2009. However, theirs is not the only forecast. IPS, the Australian Space Weather Agency, recently acknowledged the lack of activity and pushed their forecast another six months down the road.

    Jan Janssens maintains a table which contains most of the published predictions. Note that this table has not been updated in the past 12 months, as Solar Cycle 24 continues to behave unexpectedly, and forecasters have little or no additional insight on which to base new predictions.

    You’ll see in the table, no. 8, by Maris et al, reasons that Solar Cycle 24 will be small, because of the loss of energy through intense solar flares during the declining phase of Cycle 23.

    One of the most highly-experienced solar forecasters, Ken Schatten, has been wondering if the energy lost to the solar wind through low-latitude coronal holes – which are unusual at solar minimum – has left the sun with too little energy to produce more energetic spots.

    Finally, an unpublished paper (but you can find it on the web) by Livingston and Penn of the Kitt Peak Observatory notes the trend of decreased contrast between sunspots and the sun, and that if the trend continues, sunspots would vanish entirely by 2015.

    Now, you can choose to agree or disagree,  but I think John’s correct in that, so far, Solar Cycle 24 is not gearing up to be what pessimists (or optimists, depending on your attitude) that it might be. Further, he adds:

    I also should have mentioned this – from a NASA media teleconference last week about the Ulysses solar probe mission. I think the results would tend to support Schatten’s idea of the sun having an energy “leak” somewhere.

    Thanks for the insight and links, John.

  • ITC to Review SiRF/Broadcom Patent Imbroglio

    The U.S. International Trade Commission (ITC) has said it will review the determination of one of its administrative law judges that previously found that SiRF Technology infringed on patents held by Broadcom subsidiary Global Locate.

    The ITC judge ruled in August that certain SiRF products, including SiRFstarIII and SiRFInstant GPS architectures, infringed upon six Global Locate/Broadcom patents; the judge later recommended to the ITC that it issue a ban on the import of related SiRF chips into the United States.

    Both SiRF and ITC staff filed appeals independently of one another seeking a review of the ruling. Now, the ITC has said it will review claims on three out of the six patents, according to SiRF.

    The commission has requested written submissions from the parties involved to address the form of remedy, if any, that should be ordered. According to the notice, if the commission contemplates some form of remedy, it must consider the effects of that remedy upon public interest, SiRF noted.

    The final ITC ruling, slated for December 2008, is further subject to a 60-day presidential review period and can then be appealed to the Federal Circuit Court of Appeals.

    SiRF, Qualcomm Play Nice

    Apparently SiRF and Qualcomm want to avoid the legal snafu in which SiRF and Broadcom are currently embroiled. SiRF also announced that it and Qualcomm have signed a mutual Patent Non-Assertion Agreement covering each party’s patent portfolio.

    “We believe that this agreement between leading innovators of A-GPS enabled location technology will help expand the market for location-enabled products, services and content, while enabling each of us to compete in the marketplace based on product merits,” said Kanwar Chadha, SiRFs founder and vice president of marketing.

    It’s been a busy week for SiRF; on Wednesday it took the wraps off its SiRFlinkIII, a single chip that combines a GPS RF front end with a Bluetooth 2.1 + EDR controller.

  • Expert Advice: Turning from Challenge to GNSS Opportunity

    Paul Verhoef
    Paul Verhoef

    Presented here is a lightly abridged version of the plenary address by the European Commission’s Head of Unit for Galileo, Paul Verhoef, at the ION GNSS conference in Savannah, Georgia, September 16.

    After a brief Galileo snapshot of current status, I will proceed as requested with predictions of life in a multiple-GNSS world. We have secured an additional budget of €3.4 billion mainly for developing and launching the Galileo constellation, with the key objective of a full operational capability in 2013.

    Here let me talk about our second test satellite, GIOVE-B, launched on April 27. This bird is healthy and flying according to its specifications, although I hear there was a small problem that caused the satellite to go into safe mode. The engineers are currently testing the signals and using the flight and mission data to fine-tune the last parameters for the manufacturing of the 30 satellites of the constellation.

    In July the European Space Agency (ESA) launched the procurement for the Full Operational Capability (FOC). As of last week, we have a shortlist of eligible bidders for sector primes, and ESA will now start the second phase. The list will be published in the next few days. I would like to add that we have opened up this procurement internationally in accordance with the European Union’s (EU’s) World Trade Organization commitments, and with some exceptions for areas of the system that contain classified technologies. The net results will be that EU prime contractors will be able to ask for authority to use non-EU suppliers and subcontractors.

    We foresee Galileo to become operational in 2013. In the mean time, the European Geostationary Navigation Overlay Service (EGNOS) will make up the first element of the European GNSS. Just to recall, EGNOS is the augmentation system improving the accuracy of GPS and warning users of possible outages. EGNOS currently covers Europe, but extensions are being considered.

    EGNOS is in its final qualification stage. Its performance is excellent, within 100 percent availability recorded over about nine months now. The European Commission intends to contract a private operator to operate and maintain the system starting next spring. In parallel, certification for aviation use is under way with the target of end of 2009.Let me now turn to market issues that take us through the issue of a multi-constellation world.

    In Europe the emphasis has been redirected from focusing on direct revenues for the potential operator toward the possibilities to boost business, research, and the markets for GNSS applications both in Europe and worldwide.

    IP and Applications. With this new direction in mind, we are now working on two sectors: intellectual property and application issues.

    Intellectual property policy is high on our work plan for later this year and next year, and an analysis advancing on impact of various options in this context. We seek a solution balancing in a fair manner three objectives:

    • fair treatment of industries, EU or non-EU,
    • reasonable return to taxpayers’ money, and
    • ensuring the timely and sufficient availability of Galileo user receivers and downstream services at FOC.

    Against the results of a recent stakeholder consultation, we are pursuing a second closely market-related initiative, an Action Plan which spells out Europe’s objectives and plans to develop applications for GNSS.

    This will not be a marketing strategy for the European GNSS, but a list of actions that the public sector should take to support the development. For example, promote interoperability of road tolling systems in the EU and facilitate receiver development.In one word, European satellite navigation programs are on track, and we are excited that we have left behind the stormy times, and we hope that we are going to sail in calmer waters in the future.

    Spacescape Evolution

    This brings me to the GNSS fortune-telling part, as requested.

    There will be at least four global systems and at least a half a dozen regional systems in Europe, the Americas, and Asia.

    How will this affect GNSS?

    The end users have everything to gain. I like to believe those that say that Galileo — even at the paper stage eight years ago — was one of the catalysts for innovation in this sector. We will soon have four for the price of one in your next multi-constellation receiver.

    The obvious effect is that new applications will emerge as ever-more robust PNT (positioning, navigation, and timing) data penetrates service packages ranging from logistics to law enforcement.

    One cellphone maker summarized the situation for the manufacturers and end users as something between fantastic and awesome. The downstream industries are possibly the big winners, at least in the medium term, until the market reaches a saturation point and consolidation picks up pace.

    What about us GNSS providers? What’s in it for us other than footing the bill?

    Tougher Customer Requirements. We GNSS providers will need to think hard about things such as backward compatibility, trade-off management of conflicting requirements, manufacturer friendliness and, not least, listening to the users.

    We should reduce the time-to-market for new products and ensure a comprehensive and global customer support. At some point soon we need to seriously address the issue of third-party liability.

    Regulatory Work. GNSS providers believe that limited and carefully targeted regulation in satellite navigation is actually useful. Examples speak for themselves: public authorities in all four global GNSS nations have taken or plan to take regulatory measures affecting the use of GNSS. Examples: E-911 in the United States, E-112 and livestock transport in Europe, government use in China, and so on.

    Competition. Let’s face it: however governmentally, non-commercially, or multilaterally we run our systems, I do believe in the human desire for fame and reward. Each of us will want to be at least that little bit ahead of our neighbor, whatever parameters are used.  In that situation the customer will be the king and can shop around — at least if competition is not distorted with system-specific mandates, cartels, or the like.

    Trade Policy. From international competition there is usually a short way to trade policy and disputes. While trade discussions are useful, I hope we can stay clear of disputes as much as possible, as they divert resources from “the main thing.” So far that has worked quite well, yet we may need to put more efforts into verifying whether the current trade regime is sufficient and the playing field is actually level.

    Spectrum. Linked to all these developments are the various aspects of radio spectrum, some mentioned earlier today already.

    There is the increasing compatibility challenge caused by scarce spectrum, shortcomings of the International Telecommunications Union (ITU) mechanism for GNSS, and the desirability of common center frequencies, wider bandwidth, and so on. In short, a lot of work ahead of us.

    Cooperation. As you heard in my words, international cooperation will need to underpin this environment in order to ensure proper functioning of the systems.

    Evolution of Policies

    While the European Commission may be Programme Manager, it is the transport departments of the EU and its 27 member states that actually are behind Galileo. They have done this for specific purposes: they want to use it.

    Our research, space, foreign policy, and, believe it or not, finance colleagues tend to push this cart with us — usually in the same direction. As Galileo gets closer to the operational capability, the interest of the other departments, institutions, and stakeholders in Galileo and GNSS in general is likely to increase.

    It is here in the United States where you have accumulated the longest experiences in this field. As we have heard, transport and other non-military policies have started to weigh more in the management of GPS over the years.

    GLONASS is also diversifying with a higher civilian content. Our colleagues in Asia are moving forward with civil applications of higher density.

    I foresee two trends:

    • First, whatever the policy mix behind the various systems, we can observe today an element of GNSS patriotism, alive and kicking. We all want our own systems and for quite legitimate reasons. That trend is likely to continue for some time still in the form of states or groups of states deciding to build their own regional or even global systems or integrity networks. In this business, added security or sovereignty qualifies as return on investment just as well as service quality, new jobs, or straight cash.
    • This is not the only trend in town. And yes, there is a counter-current hatching in the United Nations International GNSS Committee (IGC). Already the conception years of this new forum have created somewhat the “we are in the same boat” atmosphere among GNSS providers.

    The point is that the IGC is becoming the place for all the providers and users to discuss GNSS coordination issues across several sectors (the ITU, International Maritimie Organization [IMO], and International Civil Aviation Organization [ICAO] are sector- or issue-specific).  We have already seen signs of reaching the limits of bilateral coordination, for example, regarding compatibility and interoperability in a multi-constellation world. Deliverables from the IGC so far are encouraging, and the forum helps in communication and transparency between the participants.

    I would expect to see cooperation emerging among the providers in constellation and ground-segment management from a pure cost point of view. It is like owning a sports car; as the mileage accrues over the years, the talk shifts from tuning options to maintenance bills.

    Conclusions

    The evolution of GNSS is bound to foster new applications; the quantum leap in available satellites and services will give end users and manufacturers sizeable benefits. The GNSS providers will need to adapt to this new reality and volatility and have a vision of what it is we actually want to achieve. Considerable investments in security will be needed at different levels of the systems.

    That said, where policies are concerned, we will probably be witnessing two conflicting trends: GNSS patriotism and multilateral action through the IGC.

    In the GNSS provider states, the mix and evolution of the national policies guiding GNSS development varies considerably. The tendency is towards enlarging, however, the group of stakeholders (government or other) involved in policy-making towards more and more user sectors.

    In any case, in Europe we finally believe that satellite navigation is facing a fabulous future: technology trends such as personal computing, mobile communications, and the Internet come to mind.

    We need to turn this challenge into an opportunity. There are many global issues to which satellite navigation can bring a small but important contribution such as climate change, reduction of CO2, reduction of fuel consumption, search and rescue, and much more. Ladies and gentlemen, I would like to thank again our hosts for giving me the opportunity to present our intentions with this conference, and I thank you for your attention.

  • Survey & Construction Newsletter, Early October 2008

    Solar Activity: Is There Aspirin for This GNSS Headache?

    Like the hurricane/cyclone/typhoon seasons that occur every year around the globe, one fact of life about GNSS is space weather and the solar cycle. For professionals who use GNSS on a regular basis, it’s easy to forget about it since it’s not an annual event. In fact, those of you who have been using GNSS for only the past five years haven’t experienced it at all. Why? It’s an 11 year cycle, and it’s starting to heat up.

    How does Solar Activity affect GNSS?

    There are many, many papers on this subject that can offer you a lot of depth on this subject; just google “solar cycle GPS.” In my Eric Gakstatterish sort of way, I’ll write a brief description of how it affects GNSS.

    The effect on GPS signals as they pass through the ionosphere is the largest single source of error that we see in GNSS today. Essentially, free electrons contained in the ionosphere affect the propagation of the signal as it passes through. Since the signals are traveling at the speed of light and GNSS is based on nanosecond timing, it doesn’t take much interference to introduce error.

    For a graphic and more detailed information on the ionosphere, click here.

    Modeling the Total Electron Content (TEC) of the ionosphere is something you may have heard of when reading about GNSS. TEC is directly affected by solar activity, and thus the solar cycle.

    The solar cycle is an 11-year cycle of solar activity. Following is a nice graphic from the U.S. National Oceanic and Atmospheric Administration (NOAA) that’s on their Solar Cycle 24 web page. Solar Cycle 24 is the name of the solar cycle we are entering into.

    From the graphic above, you can see the height of the next solar cycle will occur in the 2011-2012 timeframe. That’s when the TEC will be the most dynamic and the most difficult to model. You might also note that there are two prediction curves (along with their uncertainties); this is because even the experts can’t agree on just how big the next cycle will be.

     

    Which GNSS users will it affect the most?

    GPS L1 (single frequency) users will be affected the most. GPS uses a rough model, often referred to as Klobuchar (a scientist’s name), in an attempt to the model the ionosphere and minimize the effect for single frequency users. When the model closely resembles the actual TEC, then the TEC has minimal effect on single frequency accuracy and you are a happy user. When the actual TEC is much different than the Klobuchar estimate, that’s when the problem occurs. It’s sort of like that moment when you figure out you estimated 200 man-hours on a project that will take 500 man-hours … oops.

    During the low point of the solar cycle is when the TEC is easiest to predict. Looking at the chart above, we are currently at the low point and really have been in a nice place since about 2004. Over the next two or three years, it’s going to change dramatically as the character of the cycle is such that it rises sharply in the beginning.

    Autonomous GPS (using no correction source) accuracy has been very good these past couple of years (2-3 meters under ideal conditions). Because it’s been so good, some of you are relying on it for mapping. The increase in solar activity will affect you the most.

    You will see some really funky data.

    For those of you professional single-frequency GPS receivers who have built up confidence in your sub-meter mapping receivers, you need to be particularly aware. It would not be out of the ordinary for your DGPS-corrected position to have an error of more than 10 meters. That includes WAAS, DGPS beacon, commercial DGPS services, and post-processed solutions. In theory, if the accuracy of DGPS corrections (SBAS, DGPS) deteriorates sufficiently, you should be forewarned. However, how your particular piece of equipment handles that warning is up to each manufacturer.

    Practically speaking, those errors aren’t going to occur on a daily basis. That would only occur during extreme solar storms. In fact, that order of magnitude will probably be quite rare, but certainly additional error in the 0.5-meter or 1-meter range will be more common than what you see now. The fantastic performance we are seeing today from autonomous GPS as well as SBAS isn’t just because of improved technology; it’s also due to the fact that we are in low point in the solar cycle.

    Users of dual-frequency GPS receivers and multiple-frequency GNSS receivers will be affected less, but still affected. Ambiguity resolution will take longer (or not be achievable at all) during periods of heightened solar activity. However, these systems will fare better than their single-frequency brethren as multiple frequencies and shorter baseline distances typical of multiple-frequency users make it much easier to model the TEC.

    Interestingly enough, this solar cycle ,with its effects diminishing after about 2016, should be the last one where we will have such concern. Think about it: it will be 2023 or so before Solar Cycle 25 starts to crank up. At that time, L2C, L5 and GPSIII will be in full bloom, not to mention Galileo and GLONASS, so the ability of our GNSS equipment to model and mitigate the effects of TEC will be much more advanced than it is today.

    What can you do about it in the meantime?

    First of all, educate yourself and understand your equipment’s exposure to solar activity. Here are some great links.

    GPS World article from May 2003

    NOAA Solar Cycle 24 Prediction issued April 2007

    NASA feature article on the beginning of Solar Cycle 24

    www.spaceweather.com

    My esteemed GPS World colleague Richard Langley from the University of New Brunswick has also tackled this subject; he can provide you with the Richard Langleyish, scientific perspective.

    Next, towards the end of 2009, make it a point to start checking up on solar activity. A great place for Europeans to do this is at the Royal Meteorological Institute of Belgium’s website. The U.S. National Weather Service also operates the Space Weather Prediction Center. Also, note that for those users along the equator, your area is more susceptible to dynamic TEC changes.

    There is no doubt you will hear more and more about the impending solar cycle as it ramps up: more research, more data collection, and more analysis. Some space weather experts say this cycle will be worse than the last, some say it won’t. However, there’s one thing they all agree on: we won’t know until it’s here.