GPS World

Author: Alan Cameron

  • Facts, Law, Table, Pound, Hand

    So it has come to this. LightSquared officers want the FCC to investigate Brad Parkinson.

    Senator Joe McCarthy is not a good look for them.

    A young attorney of my acquaintance, who also happens to be a contributing editor to this magazine, wrote me in this regard:

    “Lawyers have an old saying — when you don’t have the law on your side, pound on the facts; when you don’t have the facts on your side,  pound on the law; and when you don’t have either, pound on the table.”

    It appears that LightSquared has run out of technical solutions that it has variably proposed, without coming up with any to solve interference with the full range of GPS uses and users, and is now reduced to complaints about process. Engineering was never its strong suit, and there are many cautionary lessons to be learned from its near-run at GPS demolition. Financiers and lawyers can bring a whole heap of spectrum danger with just a little knowledge.

    In coverage of this issue over the past year, I have tried to keep the magazine and its various newsletters away from the posturing and saber-rattling on both sides, the stock-market speculations and the wireless industry tea-leaves reading, and stick instead to the facts: test results, official statements by government agencies, and so on. You gentle readers have plenty of other outlets for hyperbole and flights of imagination that you can go to for that sort of thing, and it’s never in short supply. I hope we have served you well.

  • Out in Front: Big Bang Cheery

    By Alan Cameron

    A supersize bunch of pent-up GNSS just bust out all over. GLONASS is fully operational for the first time in more than 15 years. At least one Galileo in-orbit validation satellite broadcasts the new E1 and E5 signals, maybe both satellites by the time you read this. Compass has completed its regional navigation constellation. The first GPS III satellite testbed arrived at its integration and testing site in Colorado. The Russian SBAS is climbing back onto the air again. And QZSS has been quietly making progress, almost unnoticed.

    For the first column since last February, I can write about something besides LightSquared.

    Oops, I did it again.

    But what a breath of sweet, fresh air.

    Maybe now we can get back to the real business of this community: building systems, integrating sensors, exploring applications, and making the world a better place.

    Can’t resist one last note about those creative financiers, now under Securities Exchange Commission investigation, over at LightSquared. A little bird overheard a certain someone say in mid-December, “I was at the FCC on Monday. The discussion was only about what happens after the LS bankruptcy. They are done with LS. This is all about positioning for litigation right now.”

    Of course it’s not all over yet but the kicking and screaming. Companies have powerful lawyers and white houses have long tentacles into federal agencies.

    Be that as it may, I promised to talk about GNSS, the whole GNSS, and nothing but the GNSS.

    We, and by that I mean you, on three continents, are just kicking the milestones over. I’ve never seen a month in which so much progress was made on all fronts: GPS, GLONASS, Galileo, Compass, and QZSS. It has been my experience that a step forward for one system is often matched by a step back or at least sideways for another. It is after all a system of systems, and complex systems are by nature fraught with potential for temporary setback.

    Knock on wood, interoperability moved further toward our grasp in the period November 28 to December 16, 2011, than during any other comparable span. We sometimes talk about a coming Golden Age of GNSS. We just witnessed the Golden Growth Spurt.

    A brief note: With this issue, I assume the responsibilities of publisher of this magazine, as well as editor-in-chief. With colleagues Chris Litton (associate publisher, international account manager), the invaluable Tracy Cozzens (managing editor), and Charles Park (art director), we are collectively worth slightly south of three digits of GNSS experience. Count on us to keep a steady stream of business and technical news coming your way, and to keep this forum open for your views and opinons.

    Got something to say?

    Tell me about it.

  • Out in Front: Feds Playing Footsie

    I’ll be the first to say that I don’t know how Washington works.

    I don’t know if Washington works, but that’s another story.

    Lacking that knowledge, and a competent lawyer to pepper my filings with the requisite “Vaughn v. Rosen, 484 F.2d 820 (D.C. Cir. 1973), cert. denied, 415 U.S. 977 (1972) . . . claims of nonsegregability must be made with the same degree of detail” language, all my Freedom of Information Act (FOIA) requests for agency communications to the National Telecommunications Administration (NTIA) failed. My FOIA won-lost record stands at 0–7.

    The reason cited by the Department of Transportation for withholding 11 documents and blacking out in their entirety the two pages that it thoughtfully provided was that being any more forthcoming might “cause harm to the government’s deliberative process.” If government told the people what it was up to behind closed doors, the people might object. Shades of Tammany Hall. “I’ll decide what is in the best interest of the electorate.”

    Several government agencies, responding to a tasking by the National PNT Executive Committee, sent their thoughts on LightSquared and GPS to the NTIA, which shares responsibility for spectrum with the Federal Communications Commission. At last notice, the NTIA had not forwarded these communiques to the FCC, and it sure does not want to share them with anyone on the outside. The NTIA was first to rebuff my FOIA, followed by others. Only Interior and NASA provided substance, but in both cases the documents had already been released by a House committee.

    The Citizens for Responsibility and Ethics in Washington (CREW) knows the system a lot better than I do. Its well (or at least copiously) worded FOIA to the White House Office of Science and Technology Policy for documents related to LightSquared elicited several boxloads of same.

    A nonprofit organization, CREW uses research, media outreach, and litigation to force officials to act ethically and lawfully, and to bring unethical conduct to public attention.

    CREW is combing through the voluminous documents, as you may now also do. So far, I’ve seen effusive emails from White House staffers to corporate folks they may or may not already know, fawning all over themselves about economic benefits and job creation that a new generation of wireless technology might bring.

    Not a word yet about downside or job loss that undermining an infrastructure cornerstone will produce. In an election year, point to new or hypothetical blooms and hide the detritus.

    This just in: LightSquared formally notified the FCC that any determination must not be based on “the subjective views of the federal agencies involved.”

    Now I wonder what kind of thrall the company thinks it holds the FCC in, to instruct it so?

  • Out in Front: Catch a Wave

    Expecting guidance from FCC regulators by year’s end? LightSquared purports to do so, but a more measured evaluation finds a December decision unlikely.

    The current test cycle — hopefully not the final one — just reached its end on November 4 at White Sands Missile Range, under the Air Force’s watchful eye. That testing focused only on “cellular and personal/general navigation” receivers as specified in a September letter from the National Telecommunication and Information Agency. According to unconfirmed reports, this round of testing did not include the JAVAD GNSS precision receiver with a new filter prototype, although LightSquared lobbied strongly to have the potentially bacon-rescuing device included.

    Even if allowed, that move would have been highly premature, and ultimately misguided and misguiding. The 33 other high-precision and network GPS receivers that underwent May testing would all have to be retested, with the new filter incorporated somehow in each one, before any meaningful conclusion about technical feasibility could be drawn. Then retrofit cost issues would have to be addressed. Months of work remain before any fair and complete evaluation can occur.

    A National PNT Engineering Forum summary of the cellular and personal/general navigation testing at White Sands is expected by November 30. A complete report may not appear until December. An FCC decision that same month, or the next, or the next, would be speedy and premature beyond any precedent that even the trigger-happy commission has yet set for itself.

    As a basis for a decision on the waiver, the cellular and personal nav testing is still insufficient. At least one, probably two more rounds of testing — at bare minimum — involving the recent proposed filter fixes and a complete range of high-precision receivers should take place before putting national security, infrastructure, hundreds of thousands of jobs, and hundreds of billions of dollars of public and private-sector investments at risk.

    This doesn’t mean everyone not directly involved in testing can chill.

    This is a political and very high-stakes financial struggle, not just a series of complex technical issues. Decisions when they are made will reflect political  considerations and financial motives as well as technical test results.

    Everyone who cares about the outcome should sit down today and write letters or e-mails to their three congresspeople — two senators and one representative — stating strongly and clearly their views and reasons. Even if you have written before. Congress is the only place currently that any form of leverage can be exerted.

    We are riding a wave of change, and precariously at that. While keeping our balance, we must continually gauge the water, the wind, our own stamina — and warily watch the great white sharks that are circling.

  • Faster than a Speeding Light Particle

     

    We published a news story recently suggesting that Albert Einstein, the Mighty Hip Einie, got one thing wrong, or at least not quite totally right: the universal upper limit constituted by the speed of light. Precise-timing GPS receivers in a Geneva lab helped indicate that subatomic neutrinos can travel at a velocity just a smidge faster than the speed of light. Someone at a burning idea factory in the Netherlands riposted that the scientists erred in their conclusion because they failed to take into account the relative movement of the GPS clocks in space and thus miscalculated the neutrinos’ time of flight. We hereby refute that assertion with our heavy-lifting Innovation columnist, Richard B. Langley.

    The original news story, derived from a breathless announcement out of the European Organization for Nuclear Research (CERN) in Geneva, Switzerland, reported that Septentrio’s precise-timing GPS receivers PolaRx2eTR synchronize the time bases at CERN and Gran Sasso Laboratory in Italy, 730 kilometers away, for the OPERA experiment. Researchers at the two labs synchronized to an accuracy of a couple of nanoseconds and then measured transit speeds of 15,000 neutrino events in a neutrino beam between the two sites.

    Light moves at 299,792,458 meters per second. Let’s see, doing the math, that’s 299,792.5 kilometers per second, divide into the distance from Geneva to Gran Sasso, carry the one, cross the fingers, spit downwind, gives 0.002435017553808 seconds. Two-and-a-half thousandths of a second. 24,350 nanoseconds. If the neutrinos got to sunny Abruzzo any sooner, well then, they were the new universe record-holders.

    It turns out, the little buggers made the trip 60 nanoseconds faster than that. Killing it. Just killing it. And poking a hole in the Mighty Hip Einie’s Special Theory of Relativity.

    “This result comes as a complete surprise,” said Oscillation Project with Emulsion-tRacking Apparatus (OPERA) spokesperson Antonio Ereditato.

    Then Ronald van Elburg of the University of Groningen in the Netherlands climbed into the ring. The OPERA project researchers did not take into account the relative movement of GPS clocks in space and thus miscalculated the distance, he said. “From the perspective of the clock, the detector is moving towards the source and consequently the distance travelled by the particles as observed from the clock is shorter.”

    Thus, according to van Elburg, the travel time measured by the GPS was shorter than the travel time measured in the reference frame on the ground. Accounting for the changing distances between the GPS clocks and the neutrino detectors would lengthen the observed time of flight by 32 nanoseconds on each end of the experiment, making for a total time delay of 64 nanoseconds — close to the interval that OPERA observed using the difference between the speed of neutrinos and that of light. Case dismissed.  Einstein restored.

    Unable to parse this myself, I asked Richard Langley of the University of New Brunswick whether it seemed reasonable.

    “No, I don’t think so,” Langley replied. “Special Relativity is already taken into account whenever GPS is used, whether for timing or positioning, which amounts to the same thing, since 1 nanosecond of timing error equals about 30 centimeters of distance error (simply using the speed of light). Of course, anyone can use GPS incorrectly or infer something incorrectly. There is an error (likely) somewhere but I don’t think it is in the “standard way” that clocks are synchronized using GPS. The error is either a timing error (unrelated to Special Relativity but perhaps related to the electronics and associated delays) or a neutrino-path-length measurement error. The OPERA folks have put online their internal reports on the calibration of the GPS time link between the neutrino emitter and detector:

    http://operaweb.lngs.infn.it/Opera/publicnotes/note134.pdf

    and on how the distance travelled by the neutrinos was determined:

    http://operaweb.lngs.infn.it/Opera/publicnotes/note132.pdf

    I haven’t had time to read these reports yet but it appears, at face value, that the work was quite thorough.

    “By the way,” Richard said, “there have been a number of relevant articles in GPS World over the years. And we do apologize that some of these are no longer available digitally, due to a trashing of this site by its former owner, Questex Media Group.

  • Out in Front: C’mon, People Now

    In this hour of crisis, in this hour of need, I would recall for you the immortal words of the Brotherhood of Man, as reprised here by their disciples, Sonny and Cher:

    For united we stand,
    Divided we fall,
    And if our backs should
    ever be against the wall,
    We’ll be together,
    Together, you and I.

    Or will we?

    The LightSquared crisis has been and continues to be the most perplexing and fascinating episode I have followed in 11 years of covering the GNSS community. Fascinating because it has so many political and societal implications, as well as tangled-up technical, application, and business issues. In the end, it’s all about money. Money and power.

    It further fascinates me from a sociological point of view. The way the unfolding of this process has affected the GNSS community, in particular the subset of that community that is the GPS industry in the United States, strikes many reverberating chords.

    At first glance, we can say that the crisis has pulled a diverse community together, united it against a common foe. Witness the work of the Coalition, the agreement among the TWG sub-groups, the NPEF, the chorus of supporting letters and comments in the FCC docket, and so on. This is true — but only to an extent.

    I believe the opposite is also true: it has exposed cracks or fissures within the community, driven wedges into those cracks, and widened the cracks into gaps. It has exploited natural divisions that exist because GNSS technology is so widespread in applications and variegated in types of users. The process threatens to fracture the industry, and the community, further. That’s alarming.

    In the early going, response was fairly uniform: how can LightSquared and the FCC do this? How can we stop them? Thus the Coalition to Save Our GPS was formed. The Coalition has functioned very ably, but in fact it represents only one segment of the community: the high-precision segment. It is staffed and directed, to my knowledge, largely by Trimble and John Deere with some help and assistance from the off-shore and aviation segments. There is participation and membership from other areas, but generally, high precision drives it.

    This is also largely true of the GPS Industry Council. I am making broad generalizations that are surely inaccurate, to a degree. The GPS Industry Council earlier served the community in the pre-LightSquared negotiations of 2002 and continues to do so today alongside the Coalition It is similarly oriented towards the interests of its principal members.

    The high-precision bias, if you will, of the scenario became apparent to me when I tried to recruit webinar speakers and contributed editorial pieces from the other end of the GPS community: consumer and handheld receiver and cell-phone chip manufacturers. These companies, among whom I number Qualcomm (which long ago snapped up SnapTrack), Broadcom (acquired Global Locate a few years ago), and CSR (now owns the company formerly known as SiRF), declined to participate, speak out, or become involved in any public way. They seemed content to stand on the sidelines, watching. A newly appointed Qualcomm board member of the PNT Excomm Advisory Committee recused himself from participation in LightSquared-related activities.

    Why? Money. These companies are much closer to, in many cases are business partners with, the wireless carriers and the cell-phone manufacturers who have stock in seeing 4G happen and broadband roll out across the land. The L1 GPS companies feel they have to be fairly careful about how they proceed.

    As one person from such a company told me, “I think we tend to have a positive view, which is contrary to everyone else. This was a political issue, not a technical one, and the political wheels were in motion for a long time. Now, it’s up to us to decide how to deal with it. Whine and cry that we were cheated and duped, or seize the day and do what we are good at: engineer our way out.

    “It’s interesting how much this industry likes staring at its own navel, rather than looking (or listening) to other points of view. It is what I call ‘violent agreement’.”

    No matter how violently you may disagree with this view, it is vital that you be aware that it exists within the same group that you are part of.

    So we have the beginnings of a split, of something that could become a gulf, between the high-precision and the consumer segments of the industry.

    On the second hand, we have the military, many of whom — now these are the oldtimers — are secretly pleased by the travail the industry and civil users are going through. Because they never really liked sharing GPS with the civils anyway. However shortsighted, impractical, and shoot-yourself-in-the-foot this attitude may seem, it also exists, and is held by powerful, influential people.

    Third, some people within and without the GNSS community accept some or all of the LightSquared claims: that there’s no problem, or if there is a problem then filters can solve it, that alternative solutions are ready-to-hand or can be found through diligence. You may disagree, violently or non-violently, with these believers; you must still take them into serious account.

    Finally, JAVAD GNSS has announced a partnership with LightSquared and declared that “LightSquared not only can coexist with GPS, it complements it.” The company has always set an independent course, but this breaks new ground.

    What to do?

    My colleague Eric Gakstatter perceived the need for a more broad-based organization, an all-inclusive industry and users association, which the GPS Industry Council patently is not, however earnestly it has tried to serve that purpose in the absence of anyone else to do so.

    Almost simultaneously, Glen Gibbons wrote a column in his magazine proposing just such an association. “The need for more effective, continuing organization and representation of the GNSS community — manufacturers, service providers, and users — seems clear. . . . Common interests abound, and I’m not just referring to the RF issues that fuel the present furor,” he stated.

    We have an assortment of forums already: the Civil Global Positioning System Service Interface Committee, industry councils in the United States, Europe, and Japan, the Institute of Navigation. But these bodies cannot represent nor accomplish — it is not in their respective charters to do so — all that must be represented and accomplished.

    Building and maintaining a new entity will not be easy, because the GNSS community is more diverse, and I venture to say more divided, than we may like to admit. A consensus-driven organization of divergent interests is a very ornery thing; just ask the European Union about its efforts to mount Galileo.

    A coalition of like-minded folks united around one issue differs greatly from a broad organization assembling diverse points of view. The GPS community may never speak with one voice, even in the matter of its own survival. But other courses of action lie open to us.

    Test Till You Drop. The new phase of Lower 10 testing extends into November. After that, the JAVAD filter technology must be widely distributed, as soon as it is available, to all interested parties and rigorously tested to determine its validity and, equally important, its extrapolability to other proprietary receiver technologies well established in the field. I dare say there are many further aspects that must be thoroughly investigated and analyzed before anybody asserts that “We’re not [doing] anything that creates problems for GPS safety and service.” Because Julius Genachowski said we can’t.

    Long after the unfounded claims and the tortured analogies have lapsed into dust, the laws of electromagnetic
    behavior will go on working, as they have always done. And very admirably at that.

    C’mon, people now,
    Call on your physics.
    Everybody get together,
    Try to use your analytics,
    Right now.

  • Compass ICD in October; Harmonizing GNSS

    China’s GNSS, Compass or Beidou, intends to publish its signal interface control document (ICD) in October. Representatives of the system made an unprecedented showing at ION GNSS in Portland, and referred frankly to “internal deliberations” that may be at the root of much of the public uncertainty about the system’s planned structure and timeline. Meanwhile, representatives of other navigation satellite systems also delivered updates on their status and plans. Everyone is concerned about LightSquared interference, but everyone continues to move forward.

    This month’s column is a two-parter: a guest appearance by Len Jacobson, editorial advisory board member for GPS World magazine and president of Global Systems and Marketing Inc.  Len writes on the “Harmonizing GNSS” aspect, the briefings by all systems and their efforts to achieve compatibility and interoperability. Then I’ll return with an account of the Compass panel that formed part of the CGSIC meeting immediately preceeding ION.

    len_jacobsonHarmonizing GNSS

    by Len Jacobson

    Representatives of the International Committee on GNSS (ICG) participated in briefings and a panel discussion at the ION-GNSS Conference in Portland on Thursday, Sept. 22, 2011. The ICG is a committee formed under the auspices of the United Nations Office of Outer Space Affairs. The purpose of the panel was to acquaint the audience with the activities of the ICG and to allow the global and regional satellite navigation systems providers to describe their policies and efforts with regard to interoperability and compatibility among the various GNSS and to advise how multi-GNSS services could be harmonized.

    Rick Hamilton from the U.S. Coast Guard Navigation Center organized the panel, and Jeffrey Auerbach, from the same U.S. Department of State (DOS) office as the U.S. ICG representative Dave Turner, moderated it.

    The first speaker was Sharafat Gadimova, from the ICG Executive Secretariat. She described the functions and make-up of the ICG and suggested visiting their web site www.icgsecretariat.org for further information. The next meeting of the ICG is scheduled for December 4–9, 2012 in China.

    David Turner, the deputy director of the Office of Space and Advanced Technology in the DOS, reiterated the President’s 2010 Space Policy and in particular the addition emphasizing international cooperation and more use of foreign systems by the U.S. government to enhance GPS. Turner co-chairs Working Group (WG)-A on compatibility and interoperability. He discussed a Multi-GNSS Monitoring Network using new and existing GNSS monitoring receivers and networks. He stated that the various GNSS geodetic and timing references can be found on the ICG web site.

    Dr. Sergey Revnivykh, deputy director-general, GLONASS Information and Analysis Center, stated his desire that all GNSS be considered equal. In this sense, Russian policy differs from U.S. policy, which considers GPS as the premier GNSS. Dr. Revnivykh discussed the GLONASS System of Differential Correction and Monitoring (SCDM), the Russian version of WAAS. It will augment both GLONASS and GPS. He had to leave after his presentation so was not able to participate in the ensuing panel discussion.

    Independently, we have learned from GLONASS communications that the launch of GLONASS-M No. 42 from Plesetsk is scheduled to take place on October 1 at 20:19 UTC. The launch of GLONASS-M Nos. 43, 44, 45 from Baikonur may occur as early as November 2. The launch of GLONASS-M No. 46 from Plesetsk is now scheduled for November 22. The launch  of the next-generation GLONASS-K1 No. 12 from Plesetsk will likely slip to 2012. Additionally, Luch-5A, a Russian geostationary communications satellite that includes an SBAS payload, will launch together with Amos-5, a Russian-built Israeli communications satellite, on December 10 from Baikonur.

    Next we heard a short briefing by Xavier Maufroid from the Galileo Implementation office of the European Commission in Belgium. He stressed compatibility with all services, and then interoperability. He stated that the European Union (EU) is concerned about LightSquared (LS) because LS transmissions could affect Galileo reception in the United States and also could expand to provide a similar disruption in Europe if they were to expand into that area. And if not LS, then someone else could attempt a similar broadband service over Europe with the same potential to interfere with Galileo. He later added that 7 billion euros are budgeted for Galileo between 2014 and 2021.

    From the Chinese Electronics Technology Group came Dr. Xiancheng Ding, the deputy director-general. He described Beidou (Compass) as having nine satellites with five more to be launched in 2012. This will provide regional service by the end of 2012, including over Australia and New Zealand. Beidou has a communications capability for short messaging, which is needed in rural China.

    Dr. Ding said the Beidou signal interface control document (ICD) would be released soon. Other sources indicate it to be as early as October 2011. He indicated that Beidou is fully funded for phase 2 (regional system) and will probably be funded for phase 3 (global system).

    The final briefer was Dr. Satoshi Kogure from the Japan Space Ageny. He gave a QZSS update similar to one given in other ION GNSS sessions.

    During the panel interchange and answers to questions from the audience, various combinations of signals were discussed as needing to be compatible. That is, to not interfere in same frequency band and to comply with International Telecommunications Union (ITU) regulations. Specific signal pairs mentioned in this context included: GPS L1 and L5 with Galileo; Compass and future GLONASS CDMA; the QZSS LEX with Galileo; and others.

    A WG-A workshop proposed jointly to ICG to study the potential noise impact of too many satellites. By 2020, more than 100 satellites are expected to be transmitting the myriad of GNSS signals, with up to 35 in view at any one place. This could cause mutual interference, which in turn could cause degradation in the levels of service of the various GNSS.

    Dr. Kogure described a Multiple GNSS demo campaign sponsored in part by the Japanese Space Agency consisting of tens of receivers monitoring GNSS signals over Asia and the Western Pacific. For multi-GNSS testing there is better availability in these region as there are initially more GNSS signals in view. This experiment is a prototype of a multi-GNSS monitoring network with 20 QZSS receivers by March of 2012 and 40 by a year later. China will supply Beidou receivers to Japan for the multi-GNSS Monitoring Network in cooperation with the ICG. There will be a workshop on this topic in November in Korea.

    There is still an issue between China and the EU on frequency compatibility for authorized services, but Dr. Xiancheng said a technical solution is known. Negotiations are still ongoing.

    All members of the panel were cognizant of the LS problem and are focused on providing interference detection and mitigation for their GNNS.

    Compass ICD in October

    The long-awaited signal interface control document (ICD) for China’s growing GNSS will appear this month, according to representatives of the system who spoke in a “Compass: Progress, Status, and Future Outlook” workshop as part of ION GNSS and the CGSIC meetings in Portland in September.

    The ICD has been rumored to be available previously to receiver manufacturers within China, creating some disgruntlement among companies outside the country. One of the workshop panelists affirmed that GPS/Compass chips and receivers are being actively developed by many Chinese manufacturers and research institutes.

    The ICD announcement came among many valuable pieces of information presented during the pre-ION workshop, sponsored by the International Association of Chinese Professionals in Global Positioning Systems. The workshop was chaired by Jade Morton, professor of electrical and computer engineering at Miami University, Ohio.

    Dr. Xiancheng Ding of the Beidou Program Office described Compass as a demo system in transition to an operating navigation system. Two more satellites will launch in 2011, making a total of five new space vehicles this year,as part of a total “simple navigational system” of nine satellites that has been built up, and what is termed a “test system” over the Asia-Pacific region, to be complete by the end of the year.

    Five more satellites will rise into orbit in 2012, and the system will graduallly extend its coverage and improve its performance. Compass will start official regional service by the end of 2012, meeting user requirements in the Asia-Pacific region.

    ICD document v1.0 will be published in 2011, and probably in the month of October. It will be available for international download on the Compass website, www.beidou.gov.cn (as yet without an English version), also at www.compass.gov.cn.

    There was some disagreement among panelists as to the final targeted number of satellites in the system: either 30, or 35. Subsequent comments indicated that much of the structure may still be under discussion. The impression given was very much of a dynamic system in formation and growing rapidly.

    In a presentation on “preliminary Results of GPS/Compass Integrated Positioning and Navigation,” Dr. Uanxi Yang of China’s National Administration of GNSS and Applications reported integrated navigation with a Unicore UB 240 Compass/GPS receiver, and also mentioned a Shanghai Huace Compass/GPS receiver. Some systematic errors in Compass positioning were reported, and attributed to the sparse satellite distribution currently.

    Dr. Yang concluded with the exhortation, “Reasonable Wishes for Compass!” emphasizing the desire of the delegation to continue working hard on, but with realistic expectations for, the new system.

  • Out in Front: The Good, the Bad, the Incompetent

    Good-the-bad-and-the-ugly-WThe most efficient use of spectrum the world has ever seen benefits more than a billion people today. Two billion tomorrow, when modernized and interoperable GNSS gets real. This massive installed base constitutes a source of innovative advantage and invaluable good will for the United States.The latter arises from the high degree of trust and confidence in the United States and its stewardship of GPS, one of the most successful — and perhaps only — simultaneous foreign aid and domestic economic stimulus programs ever created.

    Smooth dealers operating inside a hedge, playing with other people’s money, want to make billions by raiding this national resource to provide video on cell phones to young audiences.

    The Federal Communications Commission has acted in ways inconsistent with reasonable public expectations of a federal rule-making agency. Early on, it gave the appearance of buying into the LightSquared agenda, issuing a ruling with undue speed.

    It has waived, explained, and proclaimed in ways that show an abject ignorance of radio frequency (there are conflicting reports as to whether agency technical staff was ever consulted by leadership prior to acceding to the LightSquared request) — and too clever by half. The chairman, rumored to be in line for the China ambassadorship, was careful not to sign the waiver himself, but have the deed done by a subordinate.

    In this act, they ignored the inherent conflict in two competing national policy objectives: the National Space Policy and the Broadband Memorandum. Rather than taking time to reconcile crucial guiding principles, the waiver plots its own course.

    The ruckus has gotten the president out on a limb, and now the agency must find a solution allowing him to crawl back before the election. Either that, or he and his advisors, including the FCC chair, will knuckle down and carry on regardless, saving political face in the short run while weakening national infrastructure and defensive capabilities.

    Never underestimate politicians’ desire to save face. In many ways, it’s all they’ve got.

    The best thing the GPS community can do during this quiet reloading period is to keep the letters and calls flowing to Congress: the safest and most fact-based action for the FCC is to conclude that the terms of the LightSquared conditional waiver have not been met and withdraw the license to deploy a terrestrial network in the 1525–1559 MHz band. This is the only approach fully consistent with both the National Space Policy and the Broadband Memorandum, as well as the FCC’s own regulations.

    At this point, any actions taken by the FCC are subject to unpredictable political considerations.

    Shootout at the cantina.

  • The System: 2 SOPS Takes Over Second IIF

    The U.S. Air Force 50th Space Wing’s 2nd Space Operations Squadron took command and control of the second GPS Block IIF satellite on August 19. SVN-63 (PRN 01) was set healthy on August 23.

    The total of 12 next-generation GPS IIF satellites built by Boeing will provide improved accuracy through advanced atomic clocks, a longer design life than legacy GPS satellites, and a new signal, L5, that will benefit civil aviation and safety-of-life applications.

    The Space and Missile Systems Center’s GPS Directorate at Los Angeles Air Force Base remained in control of the satellite during a 30-day on-orbit check-out period before hand off.

    The constellation is more robust and capable than at any other time in its history, the GPS Wing said. Members of 2 SOPS operate the largest Department of Defense satellite constellation via the Master Control Station and a worldwide network of monitoring stations and ground antennas.

    Recalls IIA to Duty. For only the second time in a quarter century, Air Force officials plan to transition a decommissioned GPS satellite back to active status. 2 SOPS staff noticed in late May that the clock on the GPS IIA SVN-30 was starting to malfunction. 2 SOPS engineers and counterparts at Boeing and Aerospace Corp. developed a plan to bring SVN-35 back in to service to replace the ailing bird. The 18-year-old satellite was decommissioned from active service in 2009 to make room for the eventual deployment of the latest GPS Block IIR vehicle; however, its navigational signal continued to function properly.

    “We keep on-orbit spares for exactly this purpose,” said Lt. Col. Jennifer Grant, 2 SOPS commander. “The robustness of our current constellation and the recent completion of the Expandable 24 architecture provide us with the flexibility to perform replacements like this with minimal impact to global users.”

    OCX Hits Bump: Does Not Pass Preliminary Design Review

    The next-generation GPS Ground Control system (OCX) under the direction of prime contractor Raytheon did not pass the recently concluded initial Preliminary Design Review (PDR).

    Not passing this critical PDR inspection so early in the OCX process and in the current fiscal environment (Congress has already trimmed the modernization budget and shifted elements to the right) constitutes a blow to the GPS modernization effort. It adds to the worry concerning the OCX-GPSIIIA gap having to do with the ability to launch the Lockheed-produced GPS IIIA space vehicles (SVs) and payloads that are scheduled to be ready for launch a full 14–16 months before the OCX ground system was originally scheduled to be able to control the launch.

    That timeline undoubtedly stretches to the right with this development.

    The PDR is a formal inspection by the government acquisition agency — the Air Force’s GPS Directorate in this case — of the high-level architectural design of the OCX automated systems and the associated C2 software. The PDR, critical for any military project but especially so for the new GPS Ground C2 system, is conducted to achieve confidence that the design satisfies the functional and nonfunctional requirements and conforms with the overall enterprise architecture. Overall project status, proposed technical solutions, evolving software products, and all associated documentation are reviewed at a high level during the PDR to determine completeness and consistency with contractual standards. The PDR also serves to raise and resolve any technical and/or project-related issues, and to identify and mitigate project, technical, security, and/or business risks affecting continued detailed design and subsequent development, testing, implementation, and operations and maintenance activities.

    Typically during a PDR the government has several choices concerning the outcome. It can:

    • Approve
    • Approve conditionally
    • Withhold approval
    • Disapprove or fail the program.

    In this case, the government chose to withhold approval and not approve conditionally or formally fail until all PDR action items are reviewed.

    LightSquared Interference

    For the first time in several months, there is little in the way of concrete news to report on this topic — as of press date August 24. The Federal Communications Commission weighs its options and scrutinizes the further data that it has requested: the number and lifespan of GPS receivers that will be interfered with, and the number of terrestrial base stations LightSquared plans to deploy. Here are highlights from the “LightSquared Watch” webinar on August 18:

    GPS is arguably the most efficient use of spectrum the world has ever seen; almost a billion people benefit from the GPS signal that is available today. This use represents a massive installed base and source of innovative advantage for the United States. Most importantly, it represents a high degree of trust and confidence in the United States and its stewardship of GPS.
    — Scott Pace

    Misinformation is rampant, and the pressure for action before analysis characterized the early stages of this process. History was reinterpreted, and the facts twisted to fit desired reality. We have heard lawyers’ assertions versus engineers’ judgements — with only the latter supported by verifiable data.
    — Jules McNeff

    Launches Round the World

    China launched a fourth inclined geosynchronous orbit (IGSO) satellite in the Beidou/Compass navigation system on July 26. Its orbit is currently centered on an East longitude of about 93 degrees, some distance away from the other three IGSO satellites. Plans call for completion of a 14-satellite constellation by 2012.

    A single GLONASS-M satellite was set to be launched on August 26. Five further GLONASS launches are planned this year: a triple and a single GLONASS-M launch in October, and the second GLONASS-K1 satellite in December.

    The first two Galileo In Orbit Validation satellites are set to be launched from French Guiana on October 20, with two more following them into orbit by mid-2012.

  • The System: LightSquared Interference with GPS

    And the Beat Goes on

    Developments in the LightSquared saga came fast and furious in June; highlights are listed below and briefly recapped in the adjacent news story. It will be dated by the time you receive this issue, as it went to press three weeks prior.

    For current events, see Top Story and Latest News, and the full versions of stories abridged here. The Navigate, Survey Scene, and GNSS Design & Test e-newsletters, free at env-gpsworld-integration.kinsta.cloud/subscribe, will keep you up to date.

    In chronological order, from late May to late June:

    • LightSquared Las Vegas Test Towers Flawed, FCC Filing Shows
    • House Bill Ensures FCC Takes No Action that Would Harm Military Use of GPS
    • Test Data Shows LightSquared Slams Medium, High-Precision GPS Receivers
    • PNT Advisory Board Finds Interference, Says Move It
    • LightSquared, FCC Rebuttals Distort Record
    • NPEF Report on Military Receivers Calls for FCC Recision
    • LightSquared Asks for, Receives Extension on Final Interference Report
    • Claims of LightSquared Solution Discounted
    • Air Transport Association Tells Congress to Protect GPS
    • Interference with GPS Poses Major Threat to U.S. Economy
    • LightSquared Applies to International Telecommunications Union for Global Signal

    Flawed Test Towers

    Results from a key round of field tests conducted near Las Vegas, Nevada, may show overly optimistic results regarding the effects of the LightSquared terrestrial signal on GPS receivers. According to a LightSquared addendum filed with the Federal Communications Commission (FCC) a week after the May 16 Working Group report, the company’s equipment broadcast during the tests at lower-than-planned levels for its eventual deployment across the United States. Further, LightSquared may not currently be prepared or equipped to broadcast according to the terms of its business plan or its conditional waiver.

    LightSquared does not appear to have developed the full software suite nor possess the full equipment to implement the plan the company says has been in preparation for many years. Critical testing was conducted under conditions that do not truly replicate what may be the case should the FCC allow the plan to go forward.

    House Bills Target the Waiver

    On May 27, the U.S. House of Representatives passed a bill stating that the FCC shall not provide final authorization for LightSquared operations until Defense Department concerns about GPS interference have been resolved. The bill then went to the U.S. Senate for its action.

    On June 23, the House Appropriations Committee approved action that would stop the FCC from expending any funds related to the LightSquared conditional waiver until all concerns have been resolved about interference with GPS. The amendment passed in a unanimous voice vote by the full committee, underscoring growing congressional concern about harm to GPS.

    The House actions and a letter to the FCC signed by 32 U.S. senators may presage a showdown over the issue between Congress and the president, who has promised increased broadband access. A 4G wireless network providing this access could be facilitated by LightSquared sales of service via its tower transmitters to wireless carriers. LightSquared has already signed a $20 billion, 15-year deal with Sprint.

    Tests Slam High-Precision Receivers

    Data from Las Vegas field tests show that wide-bandwidth, high-precision GPS receivers started feeling the effects of the LightSquared transmission about 1,800 meters from the tower. Medium-bandwidth high-precision GPS receivers started feeling the effects of the LightSquared transmission at about 1,200 meters from the tower. In each case, there was about a 200-meter buffer from when the GPS receivers started to feel the effects of the LightSquared transmission to the GPS receiver being jammed, at 1,600 meters and 1,000 meters respectively.

    GPS World has received further details of the tests but has not been authorized to publish them yet.

    Deere & Company, a major provider of precision agriculture equipment and services, notified the FCC on May 26 of substantial interference with its GPS receivers by the LightSquared signal. Deere receivers registered impact of and interference by the LightSquared signal as far away as 22 miles from a transmitter. Further, the company has found no practicable technical solution to the problem.

    PNT Advisory Board: Move ATC

    At its June 9–10 meeting, the National Space-Based Positioning, Navigation and Timing (PNT) Advisory Board found that GPS services cannot be assured if the LightSquared plan is approved, and that the only viable option for continued availability of GPS as well as new wireless broadband is to find another spectrum for LightSquared not adjacent to the GPS frequency.

    The formal recommendation reads: “The provision of GPS services cannot be assured if the LightSquared proposal for satellite and terrestrial broadband provision using the MSS L-Band receives final approval.

    “The only reasonable and viable option to continue ubiquitous availability of GPS and the provision of a new 4G wireless broadband capability would be for the FCC to assign an alternate frequency spectrum to LightSquared that has little or no probability of affecting the delivery or utilization of GPS/GNSS services.”

    During the discussion, one advisory board member, a former goveronor of the state of Wyoming, told presenter Jeff Carlisle of LightSquared, “Your definition of mitigation seems more tied to a legal argument than a common-sense argument.”

    Rebuttals Distort Record

    Claims by LightSquared’s Carlisle and FCC chair Julius Genachowski, that the GPS industry knew long ago about LightSquared’s plan for powerful terrestrial transmitters, contradict the truth. Examination of FCC filings show that the GPS industry knew about and agreed to a plan by a previous ownership of the company, for a different purpose, with a different business concept, and employing a completely different technological approach, one that would not have harmed GPS transmissions and disabled GPS users the way the current LightSquared plan does.

    The terrestrial broadband operations first unveiled in November 2010 cannot be described as ancillary to the purpose for which Lightsquared predecessors Motient, MSV, and SkyTerra received their spectrum and licenses — that is, to provide a service that was primarily a mobile satellite service. The November letter to the FCC described a new business model that turns the original concept on its head. LightSquared for the first time revealed plans to build a “nationwide network of 40,000 terrestrial base stations,” and stated that “the capacity of its fully deployed terrestrial network across all base stations will be tens of thousands of times the capacity of either of [its] satellites.”

    The deviations from established policy required to accommodate LightSquared’s new business model are not technicalities. They represent a fundamental change to a complex and interrelated set of rules that were carefully designed to protect GPS users from interference.

    The predecessor companies had to protect their own primary satellite operations from interference. The protection that their own satellite operations required was also sufficient — at that time — to protect GPS receivers. The terrestrial network and powerful signal LightSquared now proposes bear no resemblance to the operations the FCC authorized in 2003.

    Military Report Calls for FCC Retreat

    The National PNT Engineering Forum concluded after testing classified and GPS receivers under LightSquared terrestrial transmission conditions: “Significant concerns remain that operation of an ATC integrated service as originally envisioned by the FCC cannot successfully coexist with GPS.”

    The NPEF report calls for rescinding the FCC waiver for LightSquared terrestrial transmissions, conducting more thorough studies on impacts, and revisiting the 2003–2010 authorizations. The group tested a variety of military receivers under classified categorization, also known as “government receivers.”

    Final Report Withheld

    At the last minute of a June 15 deadline for the final Working Group report on interference, LightSquared asked for a two-week extension. Federal regulators granted the request, and the final report is now due on July 1.

    A spokesperson for the Coalition to Save Our GPS revealed that “The Working Group results show devastating interference to GPS and no proven method of mitigation. Delay will not change these results. These results are the same results the FCC had had before it granted the waiver.”

    Some Solution. Three days after requesting the delay, LightSquared announced it had solved the problem, by proposing to broadcast only from the lower end of its permitted spectrum band. GPS experts countered that this would still disable the functioning of high-precision receivers.

    Air Transport Opposes Waiver

    The Air Transport Association and the Aircraft Owners & Pilots Association told Congress that the only acceptable mitigation is for LightSquared’s operations to be moved outside of the L-band and away from GPS. “With so much of the early evidence showing that LightSquared’s proposed network would potentially endanger nearly every flight operating in U.S. airspace, it seems evident that no further development of this system can be allowed.”

    Going Global

    LightSquared has filed documents relative to the International Telecommunications Union, signaling intent to use its entire band at the full authorized power. The company’s goal appears to be to work internationally, circumventing U.S. regulation, to obtain permits to broadcast a terrestrial signal globally.

  • LightSquared, FCC Rebuttals Distort Record

    A claim frequently made by LightSquared spokesperson Jeff Carlisle, and recently by FCC chairman Julius Genachowski, that the GPS industry knew long ago about LightSquared’s plan for powerful terrestrial transmitters, would be a telling point — if it were true. But it is not. The verifiable fact is that the GPS industry knew about and agreed to a plan by a previous version of the company, for a different purpose, with a different business concept, and employing a completely different technological approach, one that would not have harmed GPS transmissions and disabled GPS users the way the current plan does. Calling the 2010 LightSquared plan the same as the 2003 Motient plan is running a wolf in sheep’s clothing.

    The GPS industry worked cooperatively with previous incarnations of LightSquared, known variously as Motient, Mobile Satellite Ventures Subsidiary LLC, and SkyTerra, to facilitate the provision of ancillary terrestrial component (ATC) service: a terrestrial service authorized by the Federal Communications Commission (FCC) as an ancillary component of an integrated satellite offering.

    [Definition of ancillary: Providing necessary support to the primary activities or operation of an organization, institution, industry, or system.]

    The Record. Since at least 2003, the FCC has contemplated terrestrial operations as an ancillary supplement to a primarily satellite-based service. And since 2003, the GPS industry has been aware of this, and cooperated with it. The plan involved no foreseeable harm to the GPS signal or millions of GPS users. In fact, its very design to protect its own satellite signals also protected GPS signals from interference.

    LightSquared’s predecessors — Motient, MSV, and SkyTerra, in succession — presented a series of technical proposals in limited proceedings, and the FCC accepted a series of incremental modifications of its technical rules, all against the backdrop of the fundamental requirement: that the terrestrial operations would be ancillary to and fully integrated with a primary satellite service. The GPS community evaluated changes in the technical rules in this context and did its best to cooperate in technical modifications that would apply to terrestrial operations subject to these fundamental constraints.

    More to the point, those predecessor companies had to protect their own primary satellite operations from interference. The protection that their own satellite operations required was also sufficient — at that time — to protect GPS receivers. Because of these companies’ self-interest in protecting their own satellite signals in-band, the GPS industry focused its efforts on limiting out-of-band emissions from the anticipated ATC operations to GPS reception in the adjacent spectrum band, as evidenced by the agreements reached between the parties involved.

    Ring in the New. The present situation is completely different. The current owners of LightSquared — entities affiliated with the New York hedge fund Harbinger Capital Partners — took over SkyTerra in March 2010.  That’s when everything changed.  A new senior management team, a new business plan, and a new technological implementation: 40,000 powerful terrestrial transmitters adjacent to the L1 band in which GPS operates. Nothing previously seen by the FCC or the GPS industry even hinted at this approach.

    LightSquared now proposes an extensive deployment of terrestrial transmitters, operating independently of its satellite offering, which will create interference to GPS far beyond what was contemplated by prior FCC policy and applicable rules. GPS operators understood and agreed that satellite operators in the Mobile Satellite Service (MSS) band could deploy terrestrial service on an ancillary basis to complement satellite-based services in areas where satellite reception was weak. But there was never any agreement to, nor awareness of, the kind of dense and very powerful terrestrial network that LightSquared now seeks to install.

    LightSquared spokesperson Carlisle paints his organization as involved in prior communication to and negotiations with the GPS community in connection with the ATC rules. This disguises an essential point. That was a different organization, with a different ownership and leadership, a different business plan, and a different technology to back it up.

    Carlisle himself says so in a November, 2010 update letter to the FCC, which is when the rumbling really began.

    “In the six years since LightSquared’s [initial terrestrial] application was granted, control of the company has been transferred and its business plans have evolved.”

    FCC chairman Julius Genachowski picked up the ball in a recent letter replying to Senator Charles Grassley’s concerns about LightSquared interference. “It should be no surprise to anyone involved in the LightSquared matter that the company was planning for some time to deploy a major terrestrial network in the spectrum adjacent to GPS.”

    If an untruth is repeated enough times in enough different places, it begins to pass itself off as the truth.

    Two to Ponder. The evolution of LightSquared’s business model involves two key elements, both of them at odds with established FCC policy, not to mention GPS viability — and thus not reasonably anticipatable by anyone.

    First, LightSquared’s proposed terrestrial broadband operations cannot be described as ancillary to the primary purpose for which its predecessors, Motient, MSV, and SkyTerra, received their spectrum and licenses — that is, to provide a service that was primarily a mobile satellite service.

    Second, a requirement for the ATC service in the MSS band was that any terrestrial service be integrated with the satellite service. LightSquared’s new business model contemplates no meaningful integration of terrestrial service with satellite service.

    The deviations from established policy and rules required to accommodate LightSquared’s new business model were not mere technicalities. They represent a fundamental change to a complex and interrelated set of rules and policies that were carefully designed to protect GPS users from interference.

    On Its Head. The November 2010 Lightsquared letter to the FCC described a new business model that turns the original concept on its head. LightSquared for the first time revealed plans to build a “nationwide network of 40,000 terrestrial base stations,” and stated that “the capacity of its fully deployed terrestrial network across all base stations will be tens of thousands of times the capacity of either of [its] satellites.”

    Under the only combined satellite/terrestrial service plan described in the letter, an end user would be provided with basic usage (that is, usage before additional charges apply) of one gigabyte of terrestrial wireless broadband usage but only 500 kilobytes of satellite date usage, less than what is needed to send a single email in many cases.

    It appears that the purpose of Lightsquared’s satellite service is, now, to provide ancillary service in remote areas not covered by the ubiquitous primary terrestrial network, or in the event that the terrestrial network is destroyed — exactly the opposite of what the FCC authorized and the GPS industry had understood and agreed to.

    In 2003, the FCC stated that: “We will authorize MSS ATC subject to conditions that ensure that the added terrestrial component remains ancillary to the principal MSS offering. We do not intend, nor will we permit, the terrestrial component to become a stand-alone service.”

    LightSquared now claims, and at least one FCC commissioner wants Congress to believe, that the GPS industry should have anticipated that what was bedrock when the FCC adopted its ATC rules would become quicksand by 2011. But there is no language in prior Commission orders that might have put the GPS community on clear notice that the rules of the game were likely to be changed in such a fundamental way.

    The Distortion. LightSquared has mischaracterized the GPS community’s earlier cooperation as permission to extend the technical rules, without further consideration, to the fundamentally different, new and far more threatening mode of operation now proposed by its 2010 re-incarnation.

    When the FCC first authorized ATC, it made it clear that in the event that services in bands adjacent to ATC operations, like GPS, suffered harmful interference, it would be the responsibility of the ATC operator, not the GPS provider, to cure that interference. If LightSquared cannot demonstrate that it will not cause – or that it alone will ameliorate – harmful interference to GPS operations, it must not be permitted to initiate service.

    A cursory examination of Carlisle’s and Genachowski’s backgrounds reveals nothing pertaining to engineering or technical knowledge. Both are lawyers. Such professional experience has proven to go far in Washington D.C., of course. That and a line of talk.

    Interestingly, Carlisle served as deputy chief and then chief of the FCC’s Wireline Competition Bureau from 2001 to 2005 — the period during which the earlier, less harmful ATC agreement was reached.  Carlisle managed the development of FCC policies on broadband and competitive entry into the local exchange market, and was the architect of FCC policies on bankruptcy of common carriers.

    Genachowski has a long-term and reportedly close relationship with President Obama, who appointed him to the FCC chairmanship.  His background as a Supreme Court law clerk has led some to speculate that he may play a strong role in determining legal strategy on FCC court cases. His official bio states that “Prior to his FCC appointment, Genachowski spent more than a decade working in the technology and media industries as an executive, investor, and board member.”

    The GPS industry is amply on record as supporting the goal of ensuring that all Americans have access to broadband services, and President Obama’s goal to make more spectrum available for wireless broadband operations. However, pursuit of those goals cannot jeopardize the many critical functions performed by GPS in the national economy, security, or defense, and the overall U.S. infrastructure.

  • The System: Third Report by LightSquared/GPS Technical Working Group

    Plus: Locata as Alternative PNT, Indian SBAS, Galileo Launch

    Slow but steady progress of the Working Group (WG) convened by the Federal Communications Commission (FCC) to study the GPS overload/desensitization issue is related in the group’s Third [monthly] Pogress Report, filed with the FCC on May 16. For the third consecutive time, the report contains little in terms of actual results of testing for interference/desensitization of GPS receivers by the proposed LightSquared terrestrial signal. It continues to carefully lay out the ground rules adopted by several subteams for testing the particular receivers in their domain. As of the date of filing, it reported, “testing is underway for six device categories and has been completed for the Space-Based Receivers category.”

    As related in May’s The System, the Working Group has self-divided into sub-teams.

    Aviation Sub‐Team. Laboratory testing was scheduled to be completed by May 20, conducted by Zeta Associates. The team’s report is being compiled, and some receivers were to be made available for field testing near Las Vegas.

    The Federal Aviation Administration (FAA) issued a flight advisory warning pilots that GPS service in one area of Nevada could be “unreliable or unavailable” May 16–27, during LightSquared testing. Tests were to be conducted in six-hour blocks.

    “Pilots are strongly encouraged to report anomalies during testing to the appropriate ARTCC to assist in the determination of the extent of GPS degradation during tests,” said the advisory.

    Cellular Sub‐Team. Two of the three laboratories engaged to perform radiated and conducted testing have added work shifts to complete their processes by the TWG’s deadline; the third lab is being configured. Forty-five models of GPS-enabled cell phones will undergo testing, following a detailed procedure described in Appendix D to the report.

    General Location/Nav Sub‐Team. This team recently added new members representing public safety users at the request of the National Public Safety Telecommunications Council (NPSTC). See related article, “LightSquared Interference with Emergency Service.“ The sub‐team has accumulated live‐sky GPS test data for use in dynamic testing scenarios, and plans further field tests in the Las Vegas, Nevada, area, described in Appendix G.

    High-Precision, Networks, Timing. The sub teams have completed testing of all devices in the NAVAIR lab facility. Some team members expect to have some receivers of the same models that have been tested by NAVAIR available for field testing in Las Vegas, and are working to develop test procedures for the field tests.

    Space-Based Receivers. The team completed its laboratory testing activities as reported on April 16, and is now reviewing the initial draft analysis of the impacts.

    Senate Letter

    Meanwhile, the U.S. Senate is showing increasing signs of life in response to the problem. As of May 23, a total of 32 senators had signed a letter to the FCC initially drafted on April 15 by two U.S. senators from the heartland, Pat Roberts (Republican, Kansas) and Ben Nelson (Democrat, Nebraska). The joint public letter urges action in the form of “asking the FCC to take all necessary steps to protect GPS.”

    What sway, if any, the Senate holds over the FCC, which forms part of the executive (presidential) branch of government, remains unclear. However, the letter does signal some heightened interest in Washington, presumably as a result of hearing from constituents. Kansas and Nebraska, of course, have large-scale farming activity, in which precision agriculture driven by GPS plays a significant role.

    The two original authors state that “the International Bureau, a sub-organization within the FCC, granted a conditional waiver to allow a single company, called LightSquared, to build tens of thousands of ground stations that may cause widespread interference to neighboring GPS signals.”

    The letter goes on to outline the many key roles that GPS plays in economic activity and specifically in “economic recovery,” public safety, aviation, and national defense. “Reliable GPS affects virtually every American,” Nelson and Roberts assert.

    They close by “calling on the FCC to ensure that GPS is not compromised in any way. To do so, the full commission must be involved and require LightSquared to objectively demonstrate non-interference as a condition prior to any operation of its proposed service. Anything less is an unacceptable risk to public safety.”

    The latest signer, Senator Chuck Grassley of Iowa, writes on his website that “Given the FCC’s haste so far, I worry that LightSquared will not have interference problems resolved before given the green light to become fully operational. Farmers shouldn’t have to worry that they’re planting the correct seed or applying the precise amount of fertilizer needed for the soil to optimally produce the crop, and ambulance drivers shouldn’t have to weather taking a wrong turn or driving into a ditch because a new system is scrambling their existing navigational technology.”

    Grassley adds, “If anything, the shadows around the LightSquared project should have led the FCC to proceed with caution rather than step on the gas. Yet the opposite happened. The agency originally planned to take public comment on a key regulation necessary for green-lighting the project for only one week. The commission relented and held the comment period open longer only after consumers and affected businesses protested.”

    Defense. Congressman Mike Turner included language in the National Defense Authorization Act (NDAA) that requires the Secretary of Defense to notify Congress if he determines there is widespread interference with the military’s use of GPS caused by a commercial communications service. Turner, the House Armed Services Subcommittee chairman on Strategic Forces, has legislative jurisdiction over space and satellite systems, and included the provision in his Mark of the NDAA.

    LightSquared Interference with Emergency Services, Public Safety

    Law enforcement, emergency medical service (EMS), and fire first-responders in the state of New Mexico who participated in LightSquared/GPS interference testing at Holloman Air Force Base have submitted reports verifying a negative effect of LightSquared transmissions on their GPS equipment.
    A cover letter from the New Mexico E-911 program director states that the reports “substantiate concerns that the LightSquared network will . . . jeopardize 911 and public safety nationwide.”

    The director of emergency services for Otero County, New Mexico, writes that “during the testing process the [ambulance’s automatic vehicle location] unit was limited to only being able to see 7 satellites at any location and upon moving just 50 yards from our position at the test site towards the [LightSquared] tower were diminished to 3 or 4 satellites and at 60 yards unable to establish any satellite connections. This is still approximately 1/8 of a mile from the tower.”

    The tests were conducted on April 15 and 16 of this year at Holloman Air Force Base, in a live sky environment.

    Locata Flight Results; ICAO to Weigh for Alternative PNT

    “The Need for an Alternative PNT” was presented to the International Civil Aviation Organization’s (ICAO) 10th meeting in Montreal, Canada, on May 19 by the Australian delegation, proposing a new method for alternative position, navigation, and time (APNT). ICAO accepted the paper, and the Locata technology it describes, placing it on the table as a potential back-up to GPS. The organization will take up the discussion at its next meeting in October.

    Locata Corporation of Griffith, Australia, also released preliminary post-processing analysis on data collected during its APNT flight trial on May 9. An aircraft fitted with a Locata receiver and several truth-reference devices recorded data for three hours while flying at approximately 7,000 feet. The Locata receiver tracked a ground-based network of six LocataLites, which provided positioning signals to cover an area of approximately 1,500 square kilometers. The aircraft flew pre-defined patterns that gave varying distances to LocataLites (3–49 kilometers) during the test.

    During this trial, the Locata first acquired and tracked LocataLite signals at a range of 51.9 kilometers, according to the company, which provided an early-stage assessment of the performance of the Locata pseudorange-based (code) solution against a high-precision carrier-phase differential GPS solution. Figure 1 shows the difference in East, North, and Height between the high-precision GPS truth carrier solution and the Locata code solution. Relative to the high-precision GPS, the Locata code solution has a 95 percent RMS in horizontal of 2.1 meters and 3.2 meters in vertical. The company attributed the larger difference in the vertical to worse dilution of precision in the vertical component for this specific physical deployment of its network. Over this test data analysis, the Locata’s average VDOP of 3.3 compared to an average HDOP of 1.5.

    One test objective, the company stated, was to obtain information on the significant tropospheric effects inherent in a ground-based system over these sorts of ranges. Further detailed analysis is now underway to measure and then reduce the residual biases present in the Locata code solution. For this first-pass data analysis these biases are approximately –0.8 meters in North and –1.1 meters in height. When these residual biases are further analyzed and reduced, Locata anticipates that the 95 percent RMS code-solution accuracies will improve to better than 1 meter horizontal and 2.5 meters vertical.

    Locata emphasized that this is an early-stage analysis of first flight tests, expressly designed to provide data for a better understanding of the Locata system’s performance characteristics in ICAO-type APNT applications, and for a USAF-contracted LocataNet deployment at White Sands Missile Range that will cover more than 6,500 square kilometers. Further flight trials are planned in the near future to refine the system.

    In Q3/2011 Locata expects papers to be published on carrier-phase performance observed over multiple flights, with presentations during ION 2011 Conference in Portland, Oregon.

    Figure 1. Difference in East, North, and Height between preliminary Locata pseudorange-based solution and high-precision differential carrier-phase GPS solution.

    Indian SBAS Aloft

    The Indian Space Research Organisation successfully launched a GSAT-8 satellite, carrying a GPS-Aided Geo Augmentation Navigation (GAGAN) satellite-based augmentation system (SBAS) transponder, on May 21, aboard an Ariane-V launch vehicle, from Kourou, French Guiana. The satellite will be stationed at 55 degrees east longitude.

    Galileo Picks October 20

    The first two operational/validation satellites of the Galileo project received a launch date of October 20 of this year. Antonio Tajani, European Commission vice-president for industry and entrepreneurship, predicted that this will keep the system on track for provision of “three early services in 2014/2015 based on an initial constellation of 18 satellites.”