GPS World

Tag: From the Editor

  • Out in Front: Apply the Seat of the Pants

    Alan Cameron
    Alan Cameron

    Not “fly by,” but “apply.” As in W. Somerset Maugham’s advice to aspiring young writers: Apply the seat of the pants to the seat of the chair.

    Get grounded. Confront the blank page, the typewriter, or the less preferable modern equipments (because instant electronics short-circuit orderly brain function) for a period of silence and contemplation. Above all, think. Then, and only then, communicate.

    Some serious word-eating now ensues. In last month’s editorial, I faulted the Architecture Evolution Plan (AEP) GPS ground control software update 5.5C for wreaking havoc with fielded receivers, both military and civil. Website news stories that I subsequently posted bore headlines driving this misconception home.

    I was wrong. Subsequent analysis by more knowledgeable and expert people has established that, yes, havoc was wreaked, but not by the software update. The deficiency resided in the factory-installed software of the respective receivers. See The System story on page 12 for details.

    In my only defense, I state that I was groping in the dark. Very incomplete word, secondhand no less, arrived just as we were preparing the issue for press. No official announcement came from the Air Force during the days that followed. We understand that internal brouhaha was brewed, stern words were uttered and written, but ultimately it was determined that the fault lay in the user segment, not with ground control or vendors thereto.

    We have it on good authority that the GPS Wing maintains, and will presumably continue to maintain, that the AEP update was absolutely perfect with no software glitches. But the Wing also realizes that none of the receiver manufacturers had any idea how the update was going to be implemented, as in what pages would be affected, and if there would be new data in places where it had not been loaded before.

    A grudging admission emerges that there may be some ambiguity in the receiver interface control documents (ICDs), and that those may need some tightening up sometime soon.

    We return to the theme of communications, in this case clear ones between the GPS Wing and the various user communities: civil, commercial, and military. For GPS to maintain its place as the world’s gold standard, there must be clear — and timely — communication between the Wing and its customers. All customers. Dual-use.

    So far, there’s no No. 2 system trying harder in this regard. But why leave the door open?

    A controversial suggestion: beta versions of future AEP updates could be released to a predefined subset of receiver maufacturers, who would test and report back concerning any glitches that occurred when their receivers saw the new software and simulated nav message for the first time.

    Work with the customers.

    I’m off to take my own medicine now.

  • Out in Front: Rocky Road to Robustness

    The news arrived after this issue had gone to press, so I pulled back this column to write about it. By early February, it will be oldish news, and further details will have appeared on our website.

    The crux: another pitfall for the GPS constellation.

    The system’s command and control operational software update uploaded in late 2009 has started wreaking some havoc with installed military receivers across many fielded platforms, as well as with some civil receivers. Whether major or minor havoc, I don’t pretend to know yet. The concept of selective availability anti-spoofing module (SAASM) figures in it, though now I’m toeing classified turf.

    Whatever the control features may be, they are designed to work with authorized military receivers that have successfully passed security tests prior to fielding. But actual live introduction of the new software has produced different results than those seen in testing: some receivers in question are intermittently not tracking Y-code.

    Corrective action could encompass either the Air Force rolling back the update or revising its software, or manufacturers modifying software within the receivers — thousands or perhaps tens, hundreds of thousands already in the field.

    The conscientious, hardworking engineers at the GPS Wing had barely recovered from the SVN49 debacle, or perhaps not even, as a work-around has yet to surface. Now this.

    In the category of small comfort, they are not alone. Recently manufactured GLONASS satellites have significant signal-generation problems. A new Compass satellite on orbit may no longer be controllable. And while Galileo inches forward, European political and industrial bickering perseveres. Ah, the bickering . . . .

    Despite these distractions in the sky and elsewhere, we should all keep our heads down, noses to the grindstone, fingers to the keyboard — and eyes on the prize. A radio-frequency signal in space, like Heinlein’s moon, is a harsh mistress. Very exacting, very demanding. Occasionally punishing. Ultimately rewarding.

    This Just In. By the time you read these words, the Loran signal may be dead and gone from U.S. territories. Thanks to the Coast Guard Commandant, the Secretary of Homeland Security, and those in the administration — perhaps the president himself — who know or care nothing about secure PNT, and who braggadaciously proclaim, “Back-up? We don’t need no steenkeen back-up!”

    Meanwhile the Air Force Chief of Staff has started saying it is critical for the military to “reduce its dependence on GPS-aided precision navigation and timing” because of its vulnerability, and supporting officers confirm that GPS has been jammed or interfered with recently.

    Do these people talk to one another? Surely they must.

    The PNT Key. More robustness will always be a good thing. Once I have two coded signals on widely spread frequencies, I’m well on my way there. This is not just within the narrow band allocated to GNSS, but across many radio frequencies, many technologies.

  • Out in Front: GPS World, 20 Years Young

    GPSW_20th_LogoThis magazine, the very one you hold in your hand or peruse digitally, hereby celebrates its 20th birthday. Hooray!

    Since its inception in 1989 and first appearance in the public eye in 1990, GPS World has provided — and continues to provide — technical and business information on global navigation satellite systems (GNSS) to engineers, product designers, manufacturers, researchers, system developers, executives, and high-level managers around the world who incorporate global positioning, navigation, and timing (PNT) technologies into their corporate strategies, operations, and product offerings to maximize profit and performance.

    Many things have changed since our birth: changes in the world, changes in GPS itself and now in GNSS, and changes in this magazine.

    The book has repositioned itself over the years from its early focus on applications to the present comprehensive yet detailed grasp of design concepts at both the space system and integrated circuit level.

    We can still say, as Glen Gibbons wrote in the inaugural issue, “Perhaps the most remarkable thing about GPS today is the enthusiasm that we find

    everywhere among people involved with the field. We want to share that enthusiasm with our readers. GPS — our world and welcome to it.”

    Double-Decade Insights

    Langley_new-mug_REV_lmRichard Langley: in the fall of 1989, GPS World’s founding editor, Glen Gibbons, approached Dave Wells, Alfred Kleusberg, and me — faculty members in the then Department of Surveying Engineering at the University of New Brunswick — about editing a “technology/product development column” in a new magazine. Since readers would have marked differences in their knowledge and expertise in the GPS area, “the column should deal with issues that have broad application and interest and are presented in terms that are accessible to as wide a range of readers as possible,” he wrote. The column was to be called simply Innovation.

    We decided that Alfred Kleusberg and I would manage the column, with Dave Wells serving as one of the inaugural members of the magazine’s Editorial Advisory Board. I took over sole responsibility for the column in 1997.

    Many Innovation columns have been tutorials including the one in the very first issue of the magazine. Written by Dave Wells and Alfred Kleusberg and titled “GPS: A Multipurpose System,” it used three different positioning scenarios to explain how GPS could provide positioning accuracies all the way from a Selective Availability-constrained 100 meters down to the sub-centimeter level. It also outlined GPS’s ability to determine platform attitude with multiple antennas and its use for accurate time transfer.

    The Innovation column has run continuously in every issue of the magazine except for August and December, when it gives way to the Almanac GNSS information pages. Next April’s column will be the 200th!

    Ed Aster, Founding Publisher: 20 Years Ago, GPS World almost didn’t happen. The idea of a magazine focussed on an unknown technology shrouded in military guise was turned down by 10 publishers before the idea was thrown at me while developing our international offices in Chester, England. It immediately made sense, as long as you had long eyes. A technology that has changed the world almost as much as the invention of the telephone. Who woulda thought. GPS leads the world and allows all countries to benefit from its quite simple premise, “Where am I?”

    GPS World: That Was Then

    During the last decade of the 20th century, the U.S. Global Positioning System achieved full operational capability. Prior to and after that key 1995 event, the technology saw active use and growth, primarily in the fields of surveying, mapping, and high-precision positioning. The technology most often took the form of a GPS receiver, frequently a stand-alone box, although active research and development into smaller form factors and integration with other technologies began.

    A 1996 Presidential Decision Directive reiterated GPS’ global availability for peaceful use. Russia’s GLONASS became irregularly active.

    Marking the practical — that is, the true — start of the GNSS era, the first integrated GPS+GLONASS RTK surveying system appeared in 1997: the GG-24 from Ashtech. The first GPS IIR (for replenishment) satellite rose that year, proving that satnav was not only here to stay, but to improve.

    Europe’s Galileo became a topic of earnest discussion.

    Double-Decade Insights

    McNeff_Jules_boxJules McNeff: Twenty Years ago, GPS was just a promise. The first Block II satellite was not yet a year old. GPS was known to only a few. It had not contributed to victory on the battlefield; it had not revolutionized earth science nor changed the way businesses and people conduct their daily activities. Now it has done all of that. It has awakened a global awareness of precise and ubiquitous position and time and of their value as essential elements of every human endeavor.

    I look forward to its next 20 years with the same anticipation and excitement I felt then.

    GerardLachapelleGerard Lachapelle: The Launch of the Block II satellites, starting in February 1989 after a hiatus of more than three years, was the most remarkable, exciting news of the time. By January 1990, six satellites had been launched with four more to come throughout 1990, an impressive accelerated schedule that had a major impact on equipment manufacturers, technology, performance, and users. It accelerated investments in research and development, and in long-term planning of major users and suppliers of positioning services.

    GPS would be a reality! The world has never been the same since!

    First Advertisers

    These companies advertised in the inaugural January 1990 issue — and we thank them!

    Three Full Pages

    • Ashtech

    Two Full Pages

    • Trimble

    Full Page

    • McDonnell Douglas
    • Magellan
    • Geodimeter
    • Wild Leitz
    • Interstate Electronics Corp.
    • Ball Aerospace
    • Oscilloquartz
    • Navstar
    • Stanford Telecom
    • Plessey/ITT
    • GE Astro Space
    • Odetics
    • CAST
    • ITT Defense

    Fractional Ads: Holden GPS, Sensor Systems, Racal, Alcatel, FTS/Austron, Allen Osborne Associates, Datum, McIntosh & McIntosh, Intermetrics, Piezo Crystal, Van Martin Systems, Navtech Seminars, GEOSurv.

    Map these companies onto their present names/ownership and enter to win the editor’s Happy Anniversary to Us Prize! Send your answers to [email protected].

    GPS World: This is Now

    During the first decade of the 21st century, the GPS industry entered early maturity and saw action in an ever-increasing number of fields: avionics, transportation, wireless communication, burgeoning consumer devices, and location-based services. Emphasis in product design shifted to the board and chip level, and GPS chips began “disappearing inside the application,” going inside other boxes fo
    r integration with other technologies.

    GLONASS declined, then rose again; Galileo got underway in fits and starts; international regional augmentations began.

    GPS World held its first Summit for 1001 GNSS VIPs with a top-level panel during the 2002 ION-GNSS conference, and a second Summit in 2004. It became the Leadership Dinner in 2006, with a Great Debate in 2007, a GNSS Election in 2008, and Brad Parkinson’s “True History of the Origins of GPS” in 2009. In each case, proceedings were subsequently shared with all our readers.

    The magazine became more than a magazine, redesigning its website to track developments in ever-diverging industry sectors, and launching e-mail newsletters focused on these specialized interests, followed by discussion forums, webinars, video interviews, job listings, and more.

    Double-Decade Insights

    ashkenazi_vidal_boxVidal Ashkenazi: As a geodesist, I consider GPS as the natural follow-on to satellite triangulation-trilateration and Transit Doppler (in the 1960s), when navigation and timing were added to straight positioning, and geodetic concepts of accuracy and reliability (renamed integrity) were adopted. We still had some difficulties in convincing the navigation community of the need to adopt a precise geodetic coordinate system (like WGS84), instead of just latitudes and longitudes.

    The imposition of Selective Availability led civilian ingenuity to come up with differential GPS, carrier-phase, and RTK. Who could have predicted in the 1990s that countless GPS applications would develop, benefiting business, governments and citizens everywhere?

    StephenC_BOXStephen Colwell: I started GPS World back in 1989. With a $1,200 investment and business plan in hand, I struggled through 43 investor presentations until finally receiving an approval nod for funds to launch the magazine. What I remember most during these times was invariably a potential investor would say “Now explain this to me again — what is GPS, and why does it need a magazine?”

     

    LONG HAULERS
    These memoirs come from founding members of our Editorial Advisory Board who still serve in that capacity! Jules McNeff is now vice president, strategy and programs, Overlook Systems Technologies; Gérard Lachapelle is professor and CRC/iCORE chair in wireless location, Department of Geomatics Engineering, University of Calgary; Vidal Ashkenazi is CEO, Nottingham Scientific Ltd. Other advisors still on board from that first issue are Paul Cross, Larry Hothem, William Klepczynski, Keith McDonald, and Brad Parkinson.Richard Langley is, as ever, a professor of geodesy and geomatics at the University of New Brunswick; Ed Aster is a vineyard owner and entrepreneur in New Zealand; Stephen Colwell writes a monthly e-mail column on the Consumer OEM sector; Glen Gibbons is a publisher in his own write, familiar to many readers.

    GPS World: Behold the Future

    Alan-CameronIn this nascent decade, the GNSS industry will enter its full maturity as truly an indispensable utility for everyday life, at individual consumer, industrial enterprise, and government organization levels. Multi-technology circuitry, which now integrates positioning with other capabilities on a single chip, will only continue its astonishing march.

    Galileo and GLONASS will achieve their promise, and Compass will join the family, forming together with GPS a veritable system of systems with highly accessible and accurate coverage and availability even in challenging environments. GPS itself will modernize, strengthen, and expand its considerable capabilities.

    As ever, GPS World will be there, up close and personal with the technology and the business, providing eyewitness accounts by researchers, product designers, program managers, and end users.

    The magazine will continue serving its international readers and advertisers, accomplishing its mission through an integrated information system of print, e-mail newsletters, websites, webinars, and videos, all communicating critical intelligence to decision-makers and technical experts.

    GPS World’s media platform, designed for and dedicated to industry’s use, is a searchable, application-specific knowledge base of GPS/GNSS-related technologies that is mapped to the markets and needs of the community’s core purchasing audience.

    Despite its name — and names may change — the magazine has never limited itself to coverage of the U.S. Global Positioning System. We chronicle the development of all GNSS: Galileo, GLONASS, and Compass; of augmentations WAAS, EGNOS, MSAS, NDGPS, QZSS, GAGAN, and GRAS. We track the integration of GNSS with other PNT technologies, such as inertial, laser, Loran, and radio frequency fields such as wireless communications, RFID, Bluetooth, ultra-wideband, and others.

    While busy writing and talking, we are also busy listening. We encourage online comments to articles appearing at env-gpsworld-integration.kinsta.cloud. We’ve started one technical discussion forum, Tech Talk, and plan to have another, on chip and circuitry design, flying within months. We administer a LinkedIn network for GNSS professionals to communicate interests, leads, queries, referrals, and open positions; our Facebook page enables members to create unique user content to build meaningful and resource-full discussion.

    We have unparalleled personal reach in every industry sector. You’ll find one or more of GPS World’s dozen correspondents and business development consultants at every important technical and business conference. Come right up and give us a piece of your mind. Please.

    GNSS — your world. We feel privileged to play a key part in it. — Alan Cameron, Editor-in-Chief

     

     

  • Out in Front: From IAIN to 101

     

    This is one of those mind puzzles that challenge you to transform one word to another in as few moves as possible.

    No, it’s not. But it does constitute a journey of sorts. I made it in a few minutes, while listening to David Last give the keynote address at the 13th World Congress of the International Association of Institutes of Navigation.

    Departure point: ballroom of the Clarion Hotel, Stockholm, Sweden, late October. Destination: GPS 101, an online webinar for engineers from PNT-related (as in, kissin’ cousins) disciplines, sometime in the near future.

    Last described the United Kingdom’s Royal Institute of Navigation (RIN), of which he is president, as “a failing business in a booming industry.” He added that many institutes of navigation struggle with falling membership and declining revenues, if not outright losses. Contrast this with huge satnav growth, and the exploding numbers of  “products that are more powerful, more user-friendly, more cost-effective, every time we have met.” Rising industry, falling professional associations.

    My concern here is not the well-being of institutes, but the global technical awareness possessed by engineers and designers from a range of industries whose products now seek to incorporate position, navigation, and/or timing. Phones, cameras, cars, binoculars, road tolling, parole anklets, and so on.

    This magazine reaches and educates those far-flung technical personnel, in addition to our readers already working in and supplying the surveying, aviation, military, marine, mapping, precision agriculture, and other more traditional positioning fields. I think we do so very successfully.

    But I was surprised by the low level of awareness evidenced by participants in July’s webinar, “The GPS Constellation and More,” with Colonel David Madden, GPS Wing Commander. Presumably attendees came from among our readers and web visitors, but some of their questions were beyond (or below) elementary. Editor Don Jewell, who moderated that webinar, saw the need for a GPS 101 course, and I fully agree.

    We don’t intend to compete with companies or institutes offering technical tutorials. Rather, to offer a stepping stone up to those tutorials, and to leverage our free and extensive global reach to engineers everywhere.

    Returning to the RIN president for Last words, “What was once a specialized set of professional techniques has expanded into an industry with hundreds of millions of users. Navigation is a unique place where bright engineers — hardware and software — work alongside systems analysts, geographers, surveyors, geodesists, mapmakers, and those who design, manufacture, market, and support navigation equipment, and those who use their products as practitioners. These people are today’s navigators.”

  • Out in Front: An SVN up for Grabs

    Wednesday evening, September 23, Savannah, Georgia, 5:30 to 7:00 p.m., Session P2b — a date that will live in GPS history. The 400 to 600 of us who were there to witness it will never forget it. The SVN-49 Review Panel.

    Unprecedented puts it mildly.

    The ION program read: “SVN49 (GPS IIR-M 20) was launched in March of 2009 to support GPS constellation sustainment as well as to bring into use the new third civil signal, the L5. During the early orbit check out of this satellite, out-of-family measurements were observed impacting the legacy GPS L1 and L2 signals. The panel will review the background, current status, issues, and options moving forward with SVN49.”

    Col. David Goldstein, chief engineer, GPS Wing, gave a frank and open history and description of the situation. The panelists explained the options under consideration for partial fixes — a complete fix and eradication of the pseudorange error is not possible — and added a few remarks, but were mostly there to answer questions and provide perspective in response to opinions from the floor.

    It reminded me — now this is a leap — of a climb I led in days of yore up Mt. Kilimanjaro. Or escorted, really; the Swahili-speaking Tanzanian porters did all the leading. About two days in and a third of the way up, we realized that because of a schedule change we had made earlier for longer safari in the Selous, we didn’t have quite enough time to climb the mountain in the accepted manner and still make it back down for the once-weekly flight out. So over muesli and mangos the next morning in the A-frame hut, I just threw it open to everyone and said, “It’s your trip. What do you want to do?”

    Folks said later that in decades of group travel, they’d never seen the like.

    Basically, that’s what Col. Goldstein, Col. Madden, and the GPS Wing did. Just threw it open. “It’s your signal. What do you want to do?”

    The most likely solution may involve a partial adjustment to the signal, and then setting it useable with the caveat that it will not perform to the same degree of accuracy as other satellites, nor uniformly for all receivers.

    Javad Ashjaee of JAVAD GNSS had an interesting suggestion, which basically amounted to what my teenagers sometimes tell me: “Deal.” That is, just turn it on, and away we go. Use the anomaly to study multipath phenomena. Of course, he is in the enviable postion of having, or producing, receivers that can separate out the so-called defined multipath element.

    However it pans out, I commend the GPS Wing for taking such an open, public, and when you come right down to it, honest approach. I  heard a bit of grumbling behind the scenes that some protocols were not adhered to in going so public. But you know what? That’s how things get done, as opposed to bogging down under cover.

    And that Kili thing. We did make it up the mountain. Some of us. Sick as all getout from the altitude. Glad to come down. But we made it. Same’s gonna happen with this SVN.

  • The View From Here: Mapping Harmony

    By Glen Gibbons

    The Global Positioning System has provided more than a few ironies in its relatively short existence: A system so accurate that, until last year, government policy required operators to degrade the quality of the open C/A-code signal. A navigation instrument more accurate than the maps across which navigators plotted their courses. Early GPS-based car guidance systems that displayed vehicle location in the middle of buildings or lakes.

    But, as with so many other aspects of daily life, what may have seemed funny before September 11 is no longer a laughing matter..

    The need for a better correspondence of location information is underscored by the urgency being given to the Federal Communications Commission’s (FCC’s) five-year-old mandate for enhanced 911 (E911) services. E911 provides mobile telephone users with the same automatic location information (ALI) of emergency calls now en-joyed by users of wireline phones at fixed sites. The benefits of ALI for getting police, firefighters, and ambulances to an emergency quickly are obvious..

    The first phase of E911 implementation — identifying the nearest cell site from which a call comes — only covers less than half of the U.S. population. Implementation of Phase II, which requires much more accurate real-time positioning, was scheduled to begin October 1. Last month, however, the FCC granted extensions to five national wireless carriers for initiating their Phase II plans. The agency still expects carriers to provide all mobile phone users with E911 coverage by the end of 2005..

    Three wireless carriers will employ handset-based assisted-GPS techniques in providing ALI that must be twice as accurate (50 meters versus 100 meters) as the “network-based” positioning that the other carriers have selected. (This should prove interesting in the marketplace. Because the E911 capability imposes no direct cost on customers, why would consumers choose non-GPS equipment and carriers offering substantially less accurate service?).

    Little of the E911 delay stems from unavailability of GPS technology. Upgrading software at switching servers is the primary cause for postponements sought for handset-based systems. Even with the lower accuracy standards, however, carriers with network-based solutions pleaded for more time to get their positioning technology to work..

    After the communications and positioning kinks are worked out of the E911 systems, public safety and commercial location-based service providers will still face an operational dilemma. That is the mismatch between positioning techniques and mapbases and differences among maps discussed earlier. Cartographers have long understood that variations among coordinate systems and datums can make the same latitude/longitude mean different things to different people. But until GPS came along, navigation and tracking techniques were so much cruder that such cartographic variations disappeared inside the error ellipse of the positioning systems..

    Under Phase II, emergency call centers (public safety answering points or PSAPs, in FCC parlance), public safety agencies, and E911 callers need to be on the same page. Use of proprietary mapbases with incompatible grid designs in either paper or electronic format is a recipe for disaster. It will create coverage ambiguities near PSAP boundaries (Which agency should handle the call?) and lead rescuers tens or even hundreds of meters away from injured or imperiled callers. Yet a distinctive reference grid seems like a much less important proprietary feature for competing map vendors than the other information and cartographic design built into their products..

    The Public X-Y Mapping Project has proposed one solution to this mishmash of maps: adoption of a U.S. National Grid (USNG) for Spatial Addressing. The USNG would effectively match up with the Military Grid Reference System (MGRS), taking advantage of that public domain systemyy?s use of the Universal Transverse Mercator (UTM) grid. MGRS is one of the most common datums residing within GPS receivers and could be made the default mode for E911 calls, according to Jules McNeff, one of the mapping project’s principals and a well-known GPS advocate.

    Agreement between civilian and military mapping standards in these days of homeland security concerns probably wouldn’t be a bad idea. And the benefits, of course, would carry over into the commercial realm of value-added location-based services, too..

    The interagency Federal Geographic Data Committee’s standards working group recently recommended adoption of USNG as a preferred national standard. “Effective implementation of USNG on maps and in GPS receivers is the single most important thing [that we] can do to improve emergency response operations nationwide almost immediately,” says McNeff. Readers interested in exploring the USNG proposal can find more details on-line at and.

    Whether it’s USNG or another universal reference system, GPS manufacturers, public safety agencies, commercial service providers, mapmakers, and the general public have a common interest in achieving a GPS-friendly national spatial standard.

  • Apocalypse 911

    By Glen Gibbons

    “Limited only by our imaginations.”

    People like to say that about uses of GPS, or what some-one would do if they won the lottery, or a child’s options when released from school into an endless summer.

    But sometimes it’s good for our imagination to have limits. Some things our hearts and minds are better off not being able to visualize.

    Consider our recent horrors. Nazi death camps. Hiroshima. Cambodia’s killing fields. Genocidal Tutsis and Hutus. And now the twin towers of the World Trade Center. The Pentagon in flames, for crying out loud!

    One moment, an idea was unimaginable; the next, it’s historical fact — indelible, inescapable, unforgettable. The world has changed, and we along with it. The new millennium has cut its teeth on the edge of a sword.

    Probably John of Patmos would have preferred not to have had his imagination stoked by revelation 2,000 years ago. Yet there it was: the fourth seal, a pale horse and rider, his companions loose in the world, wielding death by sword, famine, pestilence, and wild beasts. Four horsemen, but riding under a single banner of terror.

    Many must feel the apocalypse is bearing down on us now, like the planes bearing down on those three buildings in New York and Washington. Even the date has an ominous numerological coincidence: September 11, 9-11, the same numbers that were punched frantically into cell phones as events rushed toward their horrible destiny.

    So, we find ourselves as though on the edge of a precipice, crevasses opening ahead of and behind us: irrevocably separated from what now seems a sweetly peaceful past, the way forward blocked by an abyss of certain dangers and uncertain risks.

    The already stuttering economy has mimicked those tumbling structures in New York and Washington, although the collapse has been nowhere near as devastating or profound. We have gone down into a valley – emotionally, economically – and it may be a long way till we climb back out.

    In this long journey back to the light, however, I expect that we will find GPS has become more a part of the recovery than a victim of the decline. Why? Because it is such a fine tool.

    In the present circumstances, of course, the first uses of GPS that come to mind are the military ones. The guided missiles, the handheld and vehicle-mounted navigators, GPS/wireless locators for downed pilots, precision munitions like those discussed in an article elsewhere in this issue. Yet even as an aroused world tries to extricate the sources and agents of terror from a global body politic, we will find broader uses for GPS.

    The Volpe Transportation Systems Center report on the vulnerability of transportation infrastructures relying on GPS, released the day before the terrorist attacks, will evoke even stronger resonance now. Security has become the watchword not merely for a day, but for the foreseeable future.

    Consequently, we’ll see a lot more GPS surveying, mapping, and machine control systems at work in securing physical assets. We’ll see increased efforts to ensure the use of GPS timing that underlies the world’s synchronized telecommunications infrastructure, the Internet, power systems, local and wide area computing networks. We may even see some innovations in emergency automatic landing of aircraft seized by hijackers, as discussed in an essay in this issue.

    But I suspect that the biggest incentive that these tragic events will provoke in GPS applications will be in its use in tracking people and assets. Figuratively reaching out and touching someone, as the well-known wireless marketing slogan puts it, is no longer enough. To more completely assuage the anxious undercurrents that these events have set in motion, we’ll need to be able to reach out and locate someone, or let someone know our own location. So, too, our public modes of transportation, our material goods in transit, will demand even greater real-time knowledge of their location and status.

    Yes, a chasm has opened before us. And yet, to come safely across to the other side, it doesn’t matter how deep the abyss is, but rather how wide. Our actions in the months and years ahead can widen or narrow the gap separating the world from a better future. In that regard, we should consider the words of German philosopher Friedrich Nietzsche, “He who fights with monsters might take care so that he doesn’t thereby become a monster. If you gaze long into an abyss, the abyss gazes also into you.”

    The United States has been grievously injured, innocent people wrongfully killed. Yet every nation has some cause to cry out for justice; every human being has a right to be delivered. To navigate this perilous terrain, will require better guidance than even that available from GPS.