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  • 50+ Leaders to Watch in GNSS

    Researchers, program managers, industry executives, and innovative product developers must chart a path to success through a challenging landscape of change in global navigation capabilities and expansion in markets.

    Who are the leaders who will move the industry forward in 2006 and 2007? What strategies will they employ and what risks will they undertake? In this special report, GPS World looks ahead to identify the key influentials most likely to impact the industry this year and next.

    As distinguished and accomplished as these individuals are, they are not the only leaders moving the industry forward. Far from it. If we used the entire length of this magazine, we might have room enough to profile all the people deserving this level of recognition. So, our selection had to be a bit, well, selective. And it may be arbitrary on many counts. But we will do it again, and there will be time and room enough to include more new faces in recognition of the fast-growing nature of the GNSS industry.

    Our only rule in compiling this gallery was that the members of the magazine’s Editorial Advisory Board, who nominated most of those shown here, were themselves excluded from appearing, even though they all exemplify leadership and vision, with long careers and many important projects underway. In the end, we had to violate even that rule, as so many advisors nominated two of their number, that we did include them.

    You will hear more from these individuals — in the pages of GPS World, in technical conferences, in top-level industry and agency meetings. Whenever you have the chance to hear or talk with them, take it.

    Suman Ganguly

    President | Center For Remote Sensing, Inc.

    Ganguly assembled a group of researchers under the banner of Center For Remote Sensing, Inc. (CRS), a relatively small firm, and has carried out advanced GPS technical R&D, developing the first (or one of the first) software GPS receiver. CRS pioneered software radio technology before 1990, in communication and radars supported by the Defense Advanced Research Projects Agency and the National Science Foundation. CRS adapted these technologies for software navigation systems and currently supports advanced navigational system developments (including a variety of receivers and simulators) for several Department of Defense organizations. Involved with various software-based navigation systems, software radars, software communication systems, and related areas, Ganguly plans to continue innovating in all areas of GNSS and related fields.

    Michael E. Shaw

    Director, National Space-Based Positioning, Navigation, and Timing (PNT) Coordination Office

    As head of the new PNT Coordination Office, Mike Shaw takes a more independent role as arbiter and coordinator of U.S. policy, gaining a reputation among Assistant and Deputy Secretaries as the go-to-guy for the straight talk on GPS issues. “In light of the unprecedented growth in GNSS constellations and signals, our goal in the Coordination Office is to support the U.S. National Space-based PNT Executive Committee in improving U.S. policy and management framework governing GPS and its augmentations to ensure that this technology continues to fuel the engine of economic growth and opportunity in the United States and throughout the world.”

    Tim Murphy

    Technical Fellow | Boeing Commercial Airplane Group

    Involved in many aspects of communications, navigation, and surveillance to support future air traffic management, with a particular focus on GNSS, Murphy has helped deploy and test GNSS landing systems (GLS) using Ground Based Augmentation Systems (GBAS, also known as Local-Area Augmentation Systems, or LAAS) in several places around the world. He’ll move ahead with new operational procedures to improve airline operational efficiency and safety through use of Required Navigation Performance (RNP), much of it enabled by GNSS. “And Boeing will continue to support the extension of GBAS standards to include new levels of performance that can support GLS CAT II/III operations.”

    Elizabeth Cannon

    Professor and Head, Department of Geomatics Engineering Schulich School of Engineering | University of Calgary

    Calgary has become a key source of highly-trained GPS/GNSS specialists for both industry and other advanced research institutions. While directing studies and actively recruiting new graduate students, Cannon’s own research currently focuses on precise vehicle positioning systems that integrate GPS with low-cost inertial systems and dead-reckoning sensors. “We will also continue to analyze the new GPS (particularly L5) and Galileo signals to determine how we can best exploit these signals for precise positioning.”

    Stephen Verhoeff

    President and Chief Executive Officer CSI Wireless

    “We are excited about our future in this business as applications for GNSS mature and new ones emerge. We have learned over more than 15 years of involvement in this industry that product development, adoption rates, market awareness, and human understanding of technology all take longer to develop than what we first expect. Within this context we look forward to 2006 and 2007 as more capability is put into space, and as we drive more innovation into this market that we serve.”

    Patrick McDougal

    Vice President, Corporate Development | Inmarsat

    Inmarsat’s mobile satellite services are already integrated with GNSS, as the satellites re-broadcast GPS corrections for both EGNOS and WAAS. And Inmarsat will have overall management leadership in the newly formed Galileo Operating Company. “Due to open standards, interoperability, and converging technologies, the distinction between communication networks and positioning services will fall by the wayside,” says McDougal. “The opportunity for Inmarsat will be to tap into the revenue potential of these converging technologies. We know from our own provisioning experience that additional benefits such as increased position accuracy, system integrity, and service authentication are attractive to our customers. These benefits, to be offered by Galileo, will help to expand the market for GNSS and will further the use of mobile satellite communication networks as delivery infrastructure.”

    Stig Pedersen

    Senior Director of Strategic Marketing Thales

    “At Thales I study coming market and technology trends, but I also hope to influence them. My drive is to capitalize on trends like value-based GIS solutions and the increasing spatial awareness in the world, made more popular through products like Google Earth. These concepts can unlock the imagination of people who have never considered how GIS coupled with the latest communication technologies can enable better business. My goal is to increase the size of the market, at all levels, by implementing cost-effective, high-quality solutions that are easy for any business to adopt.”

    John T. Kelly

    Technical Director for Advanced System Development Sensor Systems Government Systems, Rockwell Collins

    “Amid the cornucopia of signals and whirlwind change, three constants exist. First, change is cyclic, and the historic pattern between reliance on external sources for navigation versus more autonomous means may peak shortly towards externally dependent approaches. Second, increased concern regarding security and fraud underscores the importance of access control and anti-spoofing, especially for militarized use. Lastly, adaptability and innovation are even more important to keep pace with change and to develop applications extending GNSS utility beyond its navigation-only roots.”

    Per Enge
    Headshot: Per Enge

    Per Enge

    Research Professor | Stanford University

    A key educator as well as researcher, Enge turns out a yearly crop of new PhDs whose R&D impact augments his own direct work. “My immediate goal is to complete the most challenging aspects of the safety analysis for the local area augmentation system (LAAS). Rare ionospheric events have proven to be the most vexing fault mode, and the Federal Aviation Administration-led team is closing in on the solution. My more long-term goal is to launch the Stanford Center for Position Navigation and Time, where we will foster the technology that will enable GPS operation in challenging signal environments — including obstructions and radio frequency interference.”

    Jocelyn Vigreux

    President | TomTom US A

    “TomTom will continue to push the envelope of innovation in 2006. Our focus has been and always will be navigation, however in 2006 TomTom will introduce products that not only help people get from A to B, but that help people get from A to B better, with a focus on personalization. Features such as the ability to listen to audiobooks, hear traffic and road conditions, and iPod compatibility are some of the ways TomTom incorporates personal lifestyles into our new navigation products. TomTom caters to the masses and plans to bring products to market that can be incorporated into everyone’s life.”

    Jim Sennott

    President | Tracking and Imaging Systems Inc.

    A small-business owner doing advanced GPS technical R&D, Sennott was one of the first to patent deeply integrated GPS receiver processing. “We will continue to offer our customers robust and highly accurate GNSS solutions in challenging reception environments: high dynamics, signal blockage, multipath, and jamming. Integration of selected GNSS engine and inertial measurement unit (IMU) sensor components with our Integrated Demodulation-Navigation and Optimal Diversity processors provides a cost-effective path for achieving desired accuracy, continuity, and integrity levels in military and civilian landing systems, test range truth systems, and vehicular guidance applications. In the coming year we look forward to upgrading our integration facilities and simulation tools to support the latest GNSS sensor and IMU technology to meet unique customer requirements.”

    Karen Van Dyke

    National Technical Expert for GPS | RITA/Volpe Center U.S. Department of Transportation

    “The U.S. Department of Transportation (DOT) faces challenges in harmonizing and coordinating research for improved use of GPS and development of augmentation systems. Currently, GPS activities are dispersed across the Operating Administrations. Without a management structure to coordinate research activities, there is the risk of duplication of effort and resources. The Volpe Center, as part of DOT’s Research and Innovative Technology Administration (RITA), will identify and track current GPS transportation applications and research activities across all DOT modal administrations; determine the GPS research activities that should be undertaken which are not being performed; identify current resources and resource gaps within DOT; identify where future GPS research efforts should be focused; and promote coordination and leveraging of GPS technical capabilities across DOT to prevent duplication of effort. RITA also will lead development of the national Positioning, Navigation, and Timing (PNT) Architecture effort on behalf of DOT.”

    Hans-Juergen Euler

    Leica Research Fellow | Corporate Technology and Innovation Leica Geosystems AG, Switzerland

    As Galileo materializes into an accessible system over the next few years, Euler plans a variety of activities using the signals provided in the in the German Galileo Test and Development Environment (GATE). “Then Galileo signal analysis paperwork meets reality. Leica Geosystems’ ideas for future processing approaches can be tested with actual combined GNSS signals. Future applications for our surveying and machine automation solutions will be even more distance-independent and robust because of combined satellite constellations.”

    Steven W. Berglund

    President and Chief Executive Officer | Trimble

    Trimble’s technology strategy has expanding GNSS capabilities at its core. The company released an L2C-capable product a full year before launch of the first IIR satellite capable of broadcasting that signal. Its R8 GNSS system and NetR5 reference station represent initial steps in product concepts that encompass GPS next-generation signals, GLONASS, and Galileo. Berglund says the company will continue to “anticipate satellite infrastructure improvements. Our plans for 2006 and 2007 are to continue to release new products consistent with this expanded GNSS architecture, contemplating the continued development of the Galileo system. Our goal remains that of offering solutions that meet our customers’ needs by using the best technology available, now and in the future.”

    Neri G. (Tom) Terry, Jr.

    Geospatial Information and Services (GI&S) Plans and Policy Officer U.S. Marine Corps Headquarters

    “One area we emphasize is full integration of the Global and National Spatial Data Infrastructure (NSDI) and GPS for our military operating forces and other users of GPS. To this end, representatives at all levels of government and the private sector are collaborating to implement a non-proprietary standards-based grid. This grid will serve as a language of location, optimized for local operations — enabling geo-addressing and a universal map index. This effort will reduce operational friction, improving the speed and efficiency of both precision operations and emergency response.”

    Javad Ashjaee
    Headshot: Javad Ashjaee

    Javad Ashjaee

    President and CEO | Javad Navigation Systems

    “In the last few years, I could not be as effective as I would have liked due to situations beyond my control. However, I am currently enjoying my independence and looking forward to a new beginning. I still spend about one-half of my time in Moscow. A frozen lake and abundance of snow there last winter introduced me to a new hobby, snowmobiling, and provided me with a nice break from work on technology. With new GPS signals, new GLONASS structures, and the Galileo ICD on the horizon, and my complete independence, I look forward to a new round of technology challenges. I have started a new venture and am fortunate to have a group of gifted colleagues with me. I am extremely excited about the possibilities that the coming years will bring.”

    Sang Jeong Lee

    Korean GNSS Task Force | Professor Chungnam National University, Korea

    In one of the world’s fastest-developing wireless and location-based services markets, Lee believes that “GNSS technology must add value to IT-related markets, especially to the wireless network market. Hence, GPS/Galileo receivers and assisted-GNSS technology will be developed.” Further, “in this kind of digital convergence market, safety should be one of the most important impact factors. In this regard, we will investigate interference mitigation technology and integrity monitoring schemes.” Finally, he will help develop plans for a regional integrity monitoring system to be deployed as part of the Korean national infrastructure.

    Rob Rovetta

    Senior Director of Product Management QUALCOMM CDMA Technologies

    With 150 million gpsOne cell phones and 500,000 Omnitracs units, QUALCOMM may be the world’s largest GPS manufacturer, by unit volume. “The adoption of GPS-enabled location services on wireless networks is accelerating in North and South America, Europe, Asia, and elsewhere around the world. QUALCOMM focus will be to expand the location services available to wireless users by enhancing our gpsOne positioning technology’s capabilities and further integrating position location into multimedia services. We will work closely with network operators, device manufacturers, and application developers and publishers to deliver a location-enhanced mobile experience to people everywhere.”

    Daniel Ammann

    Vice President of Research and Development, GNSS Software | u-blox

    u-blox is diversifying its portfolio to fit the needs of a wider clientele, from provision of assisted GPS (AGPS) and similar services through the development of specialist applications such as timing receivers to low-cost receivers for mass-market consumer products. Amman targets meeting ever-lower power requirements and shrinking die sizes, while incorporating next-generation navigation signals such as Galileo, L2C, and QZSS in multi-band, multi-system GNSS receivers. He will spearhead research efforts “exploring innovative ways of using non-GPS signals for navigation purposes as well as, as always, the challenge to achieve ever-higher sensitivity, accuracy, and reliability levels.”

    Logan Scott
    Logan Scott

    Logan Scott

    President LS Consulting

    “Location-based encryption and authentication provides an added layer of security by forcing users to be at particular locations and times to access or generate data. This is in addition to knowing the correct keys. Financial transactions, credit report security, medical records keeping, privacy protection, digital cinema transport, and military database protection are among the myriad applications. Currently I’m working with GeoCodex LLC on integrated GPS/cipher devices for use in a variety of security products. Authenticating the position solution using a variety of antispoofing techniques is one of the major challenges, particularly for the civil user.”

    Hideto “Duke” Takahashi

    Assistant General Manager, Space Business Strategy Aerospace & Electronics System Division | ITOCHU Corporation

    “With the launch of GIOVE-A and renewed Russian interest in accelerating GLONASS, it appears the global positioning, navigation, and timing (PNT) environment will emerge from GPS domination. Most states depending on these signals rely on external systems operators for PNT services. As PNT infrastructure dependence grows, it is likely that states will either want more involvement in the operation and control of these global systems or will pursue regional PNT alternatives. One such alternative is the Japanese Regional Navigation Satellite System (JRANS). A key strength of JRANS is that GPS signals will be used, but in the event GPS signals are not available, JRANS will continue to provide reliable PNT services for the entire Asian community.” While Itochu’s JRANS project has taken a back seat to QZSS for now, Takahashi and Itochu are still significant players guiding satnav developments in Japan.

    Martin U. Ripple

    Galileo Program Director | EADS Space Services

    An articulate and energetic force within the Galileo concessionaire hierarchy, Ripple has not been afraid to challenge the European Commission on issues that may be politically rational, but do not make sense from a business standpoint. He is a strong advocate of full U.S.-Europe cooperation to develop the combined satnav market. “Satellite navigation is on the brink of a new era in the same way mobile telephony was in the ’90s. I have seen during visits with car manufacturers, mobile phone integrators, and others what the future has in store, and these opportunities excite my finance heart and engineering soul. As an active part of the Galileo Concession team, I plan to implement many of the known (and unknown) satnav services with my partners and will strive to maximize satnav usage worldwide. The issue of interoperability remains my underlying conviction as there will be no global services without global standards.”

    Ann Ciganer

    Executive Director, Policy, U.S. GPS Industry Council Vice President of Strategic Policy, Trimble

    Ciganer has quietly but effectively advocated for every major GPS issue of the past 15 years, helping create the current export control regulations that allowed civilian GPS markets to blossom, and influencing development of the first Presidential Decision Directive in 1996. She identified threats to the GPS spectrum from mobile satellite services and ultra-wideband and formed coalitions with other industries to counter spectrum grabs by competing wireless services. “We will actively build on the cooperation that the industry established at the 1997 World Radio Conference to protect GNSS spectrum. Our goals are to preserve a stable GNSS noise floor to allow market-driven technology convergence, ensure a level playing field, and minimize trade barriers; actively participate in facilitating regulatory compliance such as on environmental issues that affect the industry; and promote GNSS productivity benefits worldwide.”

    Diane Cornish

    Director of Navigation Programs | Lockheed Martin Integrated Systems and Solutions

    “I have the privilege of leading a dedicated team with deep navigation expertise and commitment to the GPS mission. The team’s experience reaches back nearly 30 years to the development and deployment of the first GPS Operational Control Segment in partnership with the U.S. Air Force. On the GPS IIF program, we’re working closely with our prime, the Boeing Corporation, and the acquisition and operations USAF organizations to deploy the most comprehensive change to the Operational Control Segment since its inception. The upgrade will replace the legacy system with a distributed architecture that will provide the foundation for future capabilities and services. We’ll continue our stewardship of GPS into the coming decades through award of the next-generation space and ground systems. In the broader GNSS community, we’re excited about the possibilities for interoperability between GPS and Galileo and are forging partnerships to develop these opportunities.”

    Lee Ott

    Chief Scientist | OmniSTAR

    As part of Fugro, OmniSTAR has a long track record in positioning services. “We are fortunate enough to have a stable group of developers who have worked together since GPS was in its infancy, and our accumulated knowledge and experience in operating real-time systems gives a decided advantage. Our present HP and XP services offer unprecedented accuracy, and we are poised to take advantage of new GPS and Galileo signals as they become available. In addition, we are integrating GLONASS into our high-accuracy services to provide what we call All in Sky service.”

    Penina Axelrad

    Professor and Associate Chair Aerospace Engineering Sciences Colorado Center for Astrodynamics Research | University of Colorado

    Axelrad’s research explores the use of GPS bistatic radar to augment aircraft safety and make scientific measurements of the Earth from airborne platforms; her goal is to maximize the retrieval of information contained in GNSS signals reflected from Earth surfaces. “I am excited about new developments in the modeling and analysis of multipath that could be used to enhance the quality of the GNSS observations at permanent sites.” She helps educate the next generation of GNSS engineers and scientists through classroom teaching of satellite navigation material and involvement in multidisciplinary and multi-level research project teams. “I am also committed to using GNSS to strengthen the science, math, and engineering education of younger students by working with colleagues in math and science education to develop teaching materials that can inspire and reinforce fundamental science and math learning at the K–12 level.”

    Ray Simeon

    President | CAST Navigation

    Next-generation aircraft incorporate multiple tightly-coupled GPS/INS devices as part of their navigation systems. They also use these devices for radar, high resolution optical systems, smart weapons, mission systems, and so on. For simulating this type of environment in the lab, CAST is developing technology that will integrate multiple GPS and inertial navigation system capability into our simulators. The most critical challenge is addressing synchronization issues among all these devices as they would be on the aircraft.

    Frank van Diggelen
    Headshot: Frank van Diggelen

    Frank van Diggelen

    Vice President of Technology Global Locate, Inc.

    “Over the next two years, GPS will be designed into almost every new cell phone and many PDAs. As this happens, the innovations of the last five years are going to move into the mainstream — ephemeris over the Internet, sub-second time-to-first-fix, and the like will become standard. And, of course, the receivers we build in 2007 will not be just GPS anymore, but true GNSS with at least GPS + Galileo, and maybe GLONASS too. I plan to be contributing to all this. What I’m not planning on is much rest!”

    Martin Unwin
    Headshot: Martin Unwin

    Martin J. Unwin

    Head of GNSS/GPS Team | Surrey Satellite Technology Ltd (SSTL)

    Unwin’s team designed to spec, built, and delivered the GIOVE-A satellite on a faster track than conventional industrial procedures used for the GIOVE-B could accomplish. Although the efficient single-site SSTL is not typical of European space contractors, SSTL has demonstrated that it can deliver and is available for future business. “Using our in-orbit assets and with the University of Surrey, we will explore and develop advanced GNSS receiver technology for orbit determination on higher altitude and groups of satellites; robust and accurate attitude determination of space vehicles; remote sensing from space using GNSS reflections off the Earth’s surface; and receiver techniques and space applications of the new Galileo and GPS signals.”

    Colonel Richard L. Reaser, Jr.

    Deputy System Program Director Navstar Global Positioning System U.S. Air Force

    Leading the technical effort to negotiate an agreement with the European Union on Galileo commonality with GPS, Col. Reaser has a host of decision inputs that will influence future GNSS for civilian and military users worldwide. “We will soon launch the second GPS Block IIR-M satellite and begin fielding the Architecture Evolution Plan 5.2 Control Segment. We will award long-awaited GPS Block III Space Vehicle, Next Generation Control System, Modernized User Equipment, and Modernized Space Receiver contracts. We plan to field more aviation receivers certified to use military signals in the National Airspace System. Our new multinational agreement, GPS and Navwar Research Development Test and Evaluation Memorandum of Understanding, will provide for more international cooperation. I look forward to implementing a common navigation signal for GPS, Europe’s Galileo, Japan’s QZSS, and potentially the Russian GLONASS.”

    Curtis Hay
    Headshot: Curtis Hay

    Curtis Hay

    Director of Business Development Spirent Federal Systems

    “With the exciting changes in store for all of us come more opportunities and choices. My role is to anticipate and prepare for evolving requirements in test equipment as we see progress toward a Galileo constellation; more GLONASS satellites; more L2C, L5, and M-code-enabled GPS satellites; and continued growth of regional augmentation systems — and to satisfy our customers’ unique RF and inertial test requirements.”

    Carolyn P. McDonald

    President | NavtechGPS

    Building on 22 years of providing professional GPS/GNSS services, McDonald has her company poised to take their educational services to the next level with plans for E-learning seminar programs. New courses in 2006 for on-site training and public venues for government, military and corporate entities include Galileo Developments, Open Source GPS, and Advanced Receiver Processing of GNSS Signals. Navtech has formed a partnership with a European organization to present courses on that continent. “In 1988, someone said we had saturated the GPS training market, but in 2006 we see a bright future not only in training but also in GPS equipment sales, now the larger part of our company.”

    Paul Verhoef
    Headshot: Paul Verhoef

    Paul Verhoef

    Head of Unit, Galileo, Intelligent Transport Systems European Commission, DG TREN

    “The single biggest objective for 2006/2007 will be to put in place the public-private partnership, based on a concession contract, that will construct, deploy, and operate the Galileo satellite navigation system, and market associated services around the globe, by the year 2010. The foreseen launch of Galileo is changing the face of satellite navigation already and we are thrilled with the tremendous prospects of the technology.” Verhoef has frankly stated that Galileo needs U.S. companies and compatibility with GPS to be successful. He shows the will to cut through some of the bureaucracy that has characterized Galileo promotion and to create a cooperative environment with the United States, promoting compatibility of GPS and Galileo, as well as investment by non-European firms in Galileo equipment and applications.

    Nidhi Upparapalli

    Director of Mapping & Content | Thales

    “I drive both consumer and precision GNSS technology development. My most important work is related to delivering enhanced location-based content to users. Real-time services like traffic, weather, and predictive routing are key technologies that my team and I work on, as well as content enhanced with multimedia. But the real focus of my efforts this year is in content formatting and compression. When done well, this enables the convergence of content on multi-application GNSS devices. My work will enable you to soon carry a tiny, multi-application device that lets you position and navigate in whatever setting you choose and with an unimaginable library of location-based information and services at your fingertips.”

    Lee Vetter

    President | Integrated Guidance Systems, LLC

    “Smaller, smarter, more agile: GPS navigation’s current challenge is to extend air power’s dominance in precision guidance to smaller weapons and to our surface forces. We are witnessing the need for more precise guidance solutions to minimize collateral damage in urban close-combat settings. Jamming threats are increasingly diverse and proliferating. Our end-use customers have stated unequivocally that the war fighter is dependent on industry to achieve affordability commitments. Integrated Guidance Systems LLC, a joint venture of Honeywell and Rockwell Collins, is uniquely meeting this need by deeply integrating MEMS and SAASM technology in anti-jamming guidance and navigation solutions. Early units are hitting targets with in-spec performance at record-setting ranges. Integration of network communication links will provide the flexibility of retargeting and the intelligence of battle damage assessment, broadening the impact of GPS navigation well into the next decade.”

    Kanwar Chadha

    Founder | SiRF Technology

    “In 1995, we founded SiRF with a simple vision of taking GPS to the masses. Today, GPS-enabled location is becoming a part of consumers’ daily lives. The challenge is to meet mainstream expectations, which we in the high technology world tend to underestimate. Simply put, consumers believe that location capability ‘should be affordable and work reliably everywhere — no ifs, buts, or maybes!’ This means enhancing the location platform by improving reliability using all available sensors and signals including but not limited to GPS, Galileo, dead reckoning, and wireless; easing integration by making it smaller, lower powered and more affordable; and improving user experience through an ecosystem of location-enabled devices, content, services, and applications that makes them happy to pay for the service they want.”

    Raymond J. Swider

    Assistant for Position, Navigation and Time (PNT) and GPS Office of the Assistant Secretary of Defense for Network and Information Integration (NII) U.S. Department of Defense

    A long-standing fixture in the GPS policy community, Swider has been pushing the envelope and occasionally ruffling feathers, internally and externally, with innovative views and studies concerning ways to generate revenue to maintain the GPS constellation and introduce improvements and innovations sooner than planned. “My goals for this year are to assist NII in strengthening OSD oversight of the department’s PNT programs and policies. In particular, this means building a constructive relationship with the U.S. Air Force for keeping GPS modernization on track, ensuring that the National Security Space Office study on a future PNT architecture charts a path ahead for the department’s medium to long-term investments in PNT solutions, and working with the staff of the National PNT Coordination Office to support the goals and objectives of the National Space-based PNT Executive Committee for national level space-based PNT solutions.”

    Lionel J. Garin

    Chief Technical Officer | NemeriX SA

    An experienced industry veteran, Garin just took over the lead technical spot with this young Swiss fabless semiconductor company specializing in ultra-low-power RF and baseband integrated circuits. “The innovation cycle in the GPS industry has produced bursts of creativity approximately every four years. The latest breakthrough — assisted GPS — has brought this technology closer to the cell phone user. The next wave will blend multiple non-GNSS location technologies and federate them under GNSS to provide pervasive location anytime, anywhere. I am personally excited to be part of the next revolution coming up with Galileo.” Nemerix has opened a new R&D center in Silicon Valley to combine resident GPS expertise with its silicon technology.

    Eduardo Falcon

    Senior Vice President of Product Development Topcon Positioning Systems

    Falcon believes the future of the positioning industry depends on its ability to seamlessly integrate different technologies. “User dependency on satellite positioning will grow in all aspects of our lives. Accuracy is addictive,” he says, “so significant growth can be expected in the demand for higher accuracy positioning data provided on a constant basis, with standardized quality, regardless of local conditions. The availability of G3 (GPS, GLONASS, Galileo) technology positively impacts the ability to produce such solutions. However, the integration of GNSS with other technologies is key to producing dependable positioning with standard quality, at all times.”

    Grognard-W
    Headshot: Peter Grognard

    Peter Grognard

    CEO | Septentrio Satellite Navigation

    “In the next couple of years, the world’s community of GNSS users will enjoy many new exciting technical improvements and commercial possibilities. Septentrio is convinced that it is crucial for the success of the GNSS industry to enable early use of those new capabilities. Septentrio has a legacy of introducing receivers for new signals, such as EGNOS, L2C, and of course, Galileo. We have just introduced the AsteRx receiver, the first commercial fully Galileo-capable OEM engine, and we are committed to launching new innovative all-signals-in GNSS products in the coming months and years.”

    Ralph Garcia

    Director of GPS and Navigation Systems (GNS) | Raytheon Space and Airborne Systems Division

    “GNS applies its electronics-based technology to avionics, high anti-jam receivers and integrated GPS/INS (inertial guidance system) navigators for several high-profile weapon systems and military aircraft. The plan for 2006/2007 is to continue providing enabling solutions for platforms such as C-130 AMP, F-35 JSF, V-22 Osprey, AV8B Harrier, F/A-18 E/F, Standard Missile 3, Tactical Tomahawk, Paveway, Joint Standoff Weapon, and Miniature Air Launched Decoy. GNS is also developing advanced technology such as Miniature Navigation Demonstration and the next-generation Modern User Equipment.”

    Joel Houlton

    Vice President and General Manager, Missiles and Munitions | Honeywell Defense & Space

    “Our military customers continually challenge us to build up a GPS navigation system’s immunity to jamming and denial techniques. We have a number of GPS anti-jam approaches, fielded and under development, that address increasing thresholds for jammer resistance. The interrelationship of GPS and inertial navigation system (INS) operation is migrating from loosely coupled to deeply integrated. Front-end GPS antenna techniques are evolving to a complete digital architecture. Chip-scale atomic clock development will provide state-of-the-art timing stability and increased jamming immunity. With the array of military platforms and missions, GPS navigation is not a ‘one solution fits all’ business model. As a GPS navigation integrator, we have the flexibility to provide anti-jam organically or use outside sources. New platform starts generally require integrated solutions. Fielded products benefit from GPS/INS upgrades or add-on anti-jam antenna solutions.”

    Oscar Pozzobon
    Headshot: Oscar Pozzobon

    Oscar Pozzobon

    Technical Director, Satellite Navigation Systems | Qascom

    Examining satnav and security applications, Pozzobon has an entrepreneurial approach more reminiscent of Silicon Valley than of Europe. His ideas may challenge export control guidelines and trigger policy debates as the lines blur between commercial security or interference rejection and military anti-jam. “The drivers in the civil GNSS security market will be safety of life, secure tracking, trusted positioning, and secure time applications. We expect the GNSS security market to follow the IT security market: as use of IT technologies grew, the number and sophistication of attacks increased at alarming rates. We anticipate a similar trend in GNSS security.” The company will develop GNSS receiver security, GNSS signal security simulation tools, and the continued evolution of middleware for trusted GPS tracking.

    Per Ludvig Normark

    Chief Technology Officer | NordNav

    The first to introduce software-based satellite navigation at the commercial level, NordNav’s embedded software receiver uses host CPU to calculate position, saving space and processing power. “We are particularly excited about our contract with a Nordic mobile handset vendor to have the first software location-enabled mobile handset on the market before the end of 2006. We will then be well-positioned to expand in the Asian and North American markets.” NordNav also claims to be first to release a commercial receiver supporting the Galileo Open Service modulation; the Galileo Joint Undertaking tapped it to lead a pan-European consortium in 2006 to develop and release mobile safety applications based on Galileo.

    Philip Mattos
    Headshot: Philip Mattos

    Philip G. Mattos

    Chief Engineer, GPS and Navigation | ST Microelectronics R&D Ltd.

    “My 2006 goal is to see my ideas for high-sensitivity GPS, in personal research since about 2001 and in development at ST for the last two years, implemented in silicon and out into the field. This should bring to the high-quality market in cars and to the consumer market in handhelds a real indoor capability, rather than the limited lab or demo indoor operation of the past few years. My 2007 goal is to see those high-sensitivity products in volume, and then the Galileo designs working in the lab and starting to be designed into customer products as “Galileo-ready,” needing only software upgrade to work with the satellites as they launch. Working on Galileo study contracts from the late ’90s, before it had a name, seeing it come to fruition tracking a single satellite, then getting the first fix will be the culmination of a long and productive path.”

    Marco Falcone
    Headshot: Marco Falcone

    Marco Falcone

    System Engineering Manager | Galileo Project Office | European Space Agency

    “ESA’s absolute priority is to keep the schedule of the program on track to maintain user expectations and get into operations soon,” says Falcone. The agency will launch GIOVE-B, in the second half of 2006, to complete validation of critical payload technology in orbit, in particular the passive hydrogen maser frequency standard. Falcone will be responsible for critical design reviews of the main GIOVE-A and GIOVE-B subsystems in late 2006 and early 2007, leading to authorization to manufacture the operational system. He’ll help to ensure GNSS interoperability with GPS, in particular a common L1 signal for GPS III and Galileo and a GPS-to-Galileo time offset broadcast in the navigation message. And, he’ll participate in coordination efforts with GLONASS and QZSS.

    Phil Kelton

    GPS Military User Equipment Program Manager | Raytheon

    “The future of military GPS is bright! Technology progress and government policy changes have provided opportunities to develop military GPS modernized receivers with improved performance, improved security and reduced cost. Cell phone, personal computer, and gaming console developments have pushed ASIC technology forward while government policy changes have allowed for contractor-developed integrated security solutions. The potential exists to achieve true force-enhancing status for military GPS though the proliferation of low-cost GPS MUE.”

    Jon Ladd

    President and CEO | NovAtel

    Heading a Canadian company that has landed key contracts for reference receivers in national aviation ground networks in the United States, Japan, Europe, China, and India, Ladd has also guided NovAtel to a strong pole position in Galileo ground infrastructure — unique for a non-European company — and poised for future commercialization of Galileo technology. He plans “continued significant investment in core R&D innovation and integration — the combination of GPS with other satellite systems, as well as the integration of GNSS with other complementary technologies.” He cites the recent launch of the company’s next-generation OEMV family of receivers, capable of receiving multi-frequency, GPS and GLONASS as well as L-Band DGPS signals, as an example of what to expect.

    Michael O’Connor

    Chief Technology Officer | Novariant Inc. (formerly IntegriNautics Corp.)

    With the dramatic increase in use of high-precision GNSS for machine guidance and control, new opportunities emerge every day in agriculture, mining, transportation, asset management, and government. Pseudolite-based GPS augmentation technologies are now commercially available, and improvements in quality and quantity of signals-in-space lie right around the corner. We look forward to meeting the needs of these growing markets, with hands-free steering and visual guidance of farm vehicles; sub-inch, hands-free steering of container-moving gantry cranes in ports and rail yards; and pseudolite-based GPS augmentation systems for open-pit mining.

    Ron Hatch
    Headshot: Ron Hatch

    Ronald Hatch

    Director of Navigation Systems | NavCom Technology, Inc.

    With availability of three frequencies in GPS and Galileo nearing, Hatch’s current research includes “exploring the recently patented concept of smoothing one refraction-corrected composite phase measurement with a second. By resolving the ambiguities across two of the frequency differences and then refraction-correcting the results, a noisy measurement is obtained with no cycle ambiguity. This composite phase measurement can be smoothed with a second refraction-corrected measurement constructed to minimize the noise. As the smoothing progresses, the resulting increasingly accurate, refraction-corrected, ambiguity-resolved, phase measurement should enable real-time kinematic (RTK) accuracies across large distances.”

    Hiroaki Maeda

    Engineering Manager, Satellite Navigation and Positioning Systems Division, NEC Toshiba Space Systems Ltd.

    Maeda has key project responsibility for the Quasi-Zenith Satellite System (QZSS) over the Asia and Oceania region, envisaged chiefly as a GPS (and Galileo) augmentation providing a new integrated service, primarily for mobile land applications in Japan. He will help guide the system through its development phase in 2006–07, moving toward a first satellite launch in 2009. His research efforts also explore indoor navigation.

    Jean-Luc Issler

    Head of Transmission Techniques and Signal Processing CNES Toulouse Center Radio Frequency directorate Delegate to the Galileo Signal Task Force

    Issler’s top priorities are navigation signal design and processing and advanced navigation receivers. He is involved in the development of several GNSS receivers for space and ground applications. He predicts a generalized use of GNSS for spacecraft navigation, timing, and applications such as GNSS radio-occultations for meteorology, and is convinced of the software nature of future navigation technologic cores. With colleagues, he developed a GIOVE signal-performance evaluation system including top-level signal samplers and digitizers. The French Space Agency team also developed a very flexible GNSS signal generator, using an innovative concept that will be reused onboard Galileo.

    Marie Lage

    Owner | Dynamic Analytical Solutions

    Lage currently supports NavAir in their development of the U.S. Navy Unmanned Combat Aerial System (UCAS) program, leading the development of the Relative GPS-based landing system, which will provide the highly accurate navigation required for the autonomous landing of an unmanned vehicle the size of a tactical fighter, loaded with fuel and weapons, on a moving aircraft carrier. She also serves as chief engineer for the demonstration of Automated Aerial Refueling (AAR) for application to unmanned aerial vehicles (UAVs). The AAR program uses integrated GPS/INS with carrier phase ambiguity resolution to provide a precise navigation solution with the required integrity and continuity to support refueling operations.

    Carlo des Dorides

    Head of Concession Division | Galileo Joint Undertaking

    “I see two quite dense years ahead for the Galileo Project. The challenge is now to have the concession contract in force — financial close — within 2007. Indeed the choice to deploy Galileo adopting a project financing structure, namely a 20-year public-private partnership/concession, implies a complex contract negotiation to provide for balanced risk allocation, with the final objective to deliver the best value-for-money solution for the public sector. Certainly the Galileo project will represent a breakthrough not only in technology but also on the contractual paradigm at stake, which might disclose new frontiers to satellite programs and their exploitation objectives.”

    Winston Guillory

    Senior Vice President of Consumer & Business Sales | NAVTEQ

    A global provider of digital map data for location-based services (LBS) and vehicle navigation, NAVTEQ powers more than 60 million sets of driving instructions per day. Guillory launched the NAVTEQ Global LBS Challenge (www.LBSChallenge.com) for application developers in 2004, at a time when many doubted the real potential of the long-forecast but slow-developing market. The Challenge has elicited several promising new applications entering the market today. Guillory plans to inaugurate an LBS Developers Conference this fall, following up with further programs and map content to drive the value chains’ continued momentum.

    Christopher J. Hegarty

    Director for Spectrum Management | Center for Advanced Aviation System Development | The MITRE Corporation

    Co-editor of the second edition of standard reference text GPS Principles and Applications and a leading technical contributor to GPS and the Wide-Area Augmentation System (WAAS) in aviation, Hegarty will relinquish his role as editor since 1997 of NAVIGATION: Journal of The Institute of Navigation. He serves the Radio Technical Commission for Aeronautics (RTCA) as co-chair of Special Committee 159, Global Positioning System. “I expect to remain active advising the U.S. government on GPS and satellite-based augmentation system (SBAS) modernization, as well as the compatibility and interoperability of GPS with foreign systems including Galileo and GLONASS.”

  • Turn, Turn, Turn

    A number of factors have converged to promote the steady growth of in-vehicle navigation systems (IVNSs) within the automotive industry. When selective availability (SA) was set to zero on May 1, 2000, the performance of Standard Positioning Service (SPS) C/A-code receivers improved dramatically — virtually overnight. Users awoke the following morning and observed their receivers navigated remarkably better.


    Additionally, commercial efforts to survey and digitize the vast North American road network intensified in the early part of this decade, which led to greatly improved quality and reliability of digital map data in geographic information systems (GISs). These mapping activities continue today at the same brisk pace and promise to further reduce vehicle navigation errors due to faulty GIS data.

    Also, consumer familiarity with GPS technology has increased substantially over the past five years, spurring greater confidence in GPS-derived location data.

    In addition to these contributing factors is the primary driver behind the rapid growth in IVNS technology: The downward trend in C/A-code receiver pricing.

    In 1996, a typical handheld consumer GPS receiver cost more than $300. Today, a similar device sells for less than $100 and, at a slightly higher cost, may also contain a color display, a rich map database, and a serial interface to transfer the navigation data to an external application.

    Unit size, weight, and power consumption also have trended downward. The net effect of these individual factors has been to accelerate the use of GPS within the automotive industry.

    Road Obstacles. Nonetheless, significant technical challenges remain. A growing application of GPS/GIS technology involves providing timely and accurate turn-by-turn driving instructions to motorists. IVNSs may display these instructions on a map within the vehicle console and/or communicate the information verbally through spoken commands and street names, whichever the driver prefers.

    In either case, the systems calculate in advance the most-efficient route to the driver’s requested destination using a route generator. Route generation may occur within the vehicle client (referred to as onboard navigation) or may be performed on a remote server (offboard navigation), whereby a high-bandwidth wireless data connection downloads turn-by-turn instructions to the vehicle client.

    One of the application’s most difficult technical challenges is delivering reliable turn-by-turn navigation instructions in degraded GPS signal environments — in particular, the urban canyon environment found in most large cities.

    Tall buildings, tunnels, and other barriers frequently obscure line-of-sight range measurements to orbiting satellites, limiting the receiver’s ability to compute a fix. Reflected multipath is also a common phenomenon that degrades fix accuracy and introduces the potential for false driving instructions.

    Because many drive routes across North America pass through these environments, a reliable and cost-effective technical solution is required to overcome these challenges. Furthermore, a robust and repeatable method to test this system is needed to measure compliance with performance requirements across a broad spectrum of vehicles.

    Inertial Sensors. A common approach in the automotive industry to minimizing the effects of degraded sky visibility and harsh urban multipath involves coupling the GPS receiver with an inertial sensor such as a gyroscope.

    This dead-reckoning approach is supported by years of industrial research in applied Kalman filtering and sensor error modeling. However, there are two significant challenges to commercializing this approach for IVNSs:

    • 1. First, to ensure two-dimensional (2D) rate gyros operate properly, we must mount gyros tangent to the Earth’s sur face (that is, flat or horizontal). This is not always feasible given the orien-tations of some embedded vehicle navigation systems. We can partially obviate this constraint by employing additional accelerometer sensors, but this approach introduces substantial design and manufacturing complexity. Replacing the 2D-rate gyro with a 3D gyro also solves the mounting problem, but at a significantly increased expense.
    • 2. The second drawback of the gyro-based approach is its cost. Although the price of automotive-grade gyros gradually has trended downward over the past five years, a basic 2D device that satisfies strict automotive environ-mental requirements still costs a minimum of $10–12 in large quantities (more than one million). Current cost pressures in the automotive industry encourage suppliers and esigners to satisfy technical requirements at the lowest possible expense.

     Figure 1 ABS system diagram
    Figure 1 ABS system diagram

     

    For these reasons, automakers and their IVNS suppliers have recently begun pursuing the innovative alternative of using independent wheel-speed sensor (WSS) measurements from the front and rear axles to calculate changes in yaw rate.

     

    Wheel-Speed Sensors

     

    WSSs are a fundamental component of the antilock brake system (ABS), which is standard equipment on nearly all new vehicles. They generate electrical pulses at frequencies proportional to the rotation rate of the individual wheels and deliver these signals to the ABS controller as shown in Figure 1.

    Differencing the pulse rates between the left and right wheels allows an IVNS to calculate changes in vehicle heading. The system also can determine nondirectional vehicle speed by averaging the left and right signals.

    Figure 2 Wheel velocities
    Figure 2 Wheel velocities

    The generalized equations for yaw rate estimation are given as (see Figure 2):


     

    where the V xx terms represent the velocities at each wheel (first subscript: l = left, r = right; second subscript: f = front; r = rear) and tw r is the track width of the rear axle (the distance between the rear-wheel tire tracks).

    Similarly, yaw rate derived from the front wheels is defined as:


     

    where δ is the steering angle. Note the effective track width for the front wheels varies according to the radius of the turn. We must model this effect appropriately in software to accurately compute heading rate using data from the front wheels.

    Data Distribution. Use of WSS signals to perform dead reckoning is also appealing because ABS controllers transmit independent wheel-speed measurements at regular and frequent intervals over the vehicle local area network (LAN) that links together the various onboard microprocessors.

    Many IVNSs include a gateway to the vehicle serial data bus; therefore no additional input pins are required for these systems to receive the WSS electrical pulses. Obtaining these periodic wheel-speed data is simply a matter of modifying the LAN controller software within the navigation system to retrieve these messages and deliver them with minimum latency to the embedded GPS receiver in the desired format.

    Directional Accuracy. How accurately can an IVNS use WSS data to calculate changes in vehicle direction?

    Consider a vehicle with 27-inch (68.6-centimeter) -diameter tires (measured tread-to-tread) with nominal air pressure, rear track width of 62 inches (157.5 centimeters) and sensor resolution of 47 teeth per rotation. The worst-case resolution based on 1-pulse-per-second quantization error and sufficiently high data sampling rate by the ABS controller can be obtained as follows:


     

    By using WSS measurements from both wheel pairs simultaneously, we can improve this value by a factor of two, achieving a heading rate resolution of 0.84 degree per second. This measurement resolution equates to a maximum accumulated error of 13 degrees over one-quarter mile (0.4 kilometer) when traveling at 50 miles per hour (80.5 kilometers per hour). In practice, actual results are considerably better because uncorrelated jitter in the left and right wheel sensor data is smoothed out over time (see Figure 3).

    Figure 3 Sample wheel-speed sensor data. Epoch interval is approximately 53 milliseconds.
    Figure 3 Sample wheel-speed sensor data. Epoch interval is approximately 53 milliseconds.

     

    Design Challenges

     

    While the example above illustrates WSS dead reckoning performance under worst-case data quantization conditions, a num-ber of important variables must be factored into the system design to achieve reliable navigation performance under various conditions.

    Sensor Type. Automotive WSSs are classified as either active or passive. Active sensors are based on a Hall-effect transducer using an active magnetic pickup to convert wheel motion to an electrical signal.

    Active sensors have the advantage of performing well at extremely low speeds. Conversely, passive sensors use the principle of variable reluctance, in which the sensor teeth travel through a passive magnetic field at sufficient speed to generate a low voltage analog waveform (Figure 4).

     Figure 4 Passive wheel-speed sensor
    Figure 4 Passive wheel-speed sensor

    These types of sensors exhibit a deadband, or a discrete speed below which motion is undetected (typically 2 to 5 kilometers per hour or 1.2 to 3.1 miles per hour). This design limitation can dramatically degrade vehicle navigation performance if the dead-reckoning software within the GPS receiver is not designed to identify this condition.

    A challenging situation occurs when one wheel sensor is generating pulses while the opposite wheel sensor does not. This may occur, for example, when a vehicle initiates a gradual turn after being stopped at an intersection — for a brief period of time the inside wheel may not rotate fast enough to generate electrical pulses.

    The same situation may also occur if the wires carrying the electrical signals from the WSS pairs to the ABS controller are significantly different in length, causing further attenuation of the weaker signal.

    The temporary absence of sensor data that may occur in these examples might fool the dead-reckoning algorithm into underestimating the turn radius, consequently leading to an incorrect calculation of the vehicle heading. However, through careful, real-time analysis of the independent wheel-speed data, the system typically can detect this condition, thereby preventing mistakes in vehicle heading determination.

    Sensor Tooth Count. The number of sensor teeth that pass through the magnetic pickup dictates the number of pulses generated per rotation. Heavy-duty vehicles such as trucks and sport utility vehicles often employ sensors with higher tooth counts. Smaller passenger cars may use sensors with fewer teeth. Although higher tooth counts provide greater quantization of wheel-rotation rate, it is important to design the system to operate reliably when fewer sensor teeth are present.

    Tire Size. Changes in tire size occur constantly based on temperature, altitude, air pressure, and tread wear. Tires occasionally fail and must be replaced, often with a smaller-diameter spare.

    Furthermore, some owners prefer to install custom wheels on their vehicles. As tire diameter varies, the distance traveled per WSS pulse also varies.

    The dead-reckoning filter within the GPS receiver navigation engine must quickly adapt to all of these incremental changes in tire size to work properly under all conditions. This adaptation process is analogous to the continual estimation of gyro bias and drift terms in a traditional Kalman filter.

    LAN Variability. The ABS controller must transmit wheel-speed messages across the vehicle LAN at a minimum rate of 10 Hz to provide sufficient resolution for the WSS dead-reckoning filter to detect small changes in heading.

    Although this requirement is generally satisfied by most LAN architectures, not all new ABS controllers transmit wheel-speed data at an equivalent rate. Furthermore, there is broad diversity of LAN architectures and wheel-speed message formats between vehicles and vehicle manufacturers — requiring the LAN controller within the IVNS to flexibly adapt to the host serial data interface.

    To simplify the processing of dead-reckoning inputs to the GPS receiver, LAN messages typically are accumulated at one-second intervals triggered by the rising edge of the GPS 1-pulse-per-second pulse.

    It is important to note that wheel-speed LAN messages typically are not synchronized with an external timing source such as GPS. For example, a vehicle LAN designed to operate at a 20-Hz rate may actually transmit wheel-speed messages every 53 milliseconds — slightly slower than the 50 milliseconds expectation.

    Because wheel-speed inputs are accumulated at precise one-second boundaries, the pulse-count inputs to the GPS receiver may spike every few seconds, giving the appearance of sudden decelerations and accelerations of the vehicle. This is simply because the LAN transmit interval may not multiply evenly into one-second boundaries.

    This phenomenon is an artifact of message timing and will not affect navigation performance if it is managed properly in software. This effect is illustrated in Figure 5.

     Figure 5 GPS-LAN timing mis-synchronization
    Figure 5 GPS-LAN timing mis-synchronization

    Vehicle Chassis. Many important dead-reckoning parameters such as wheel track, wheelbase, center of gravity, sensor type, and minimum turn radius vary substantially from vehicle to vehicle.

    These chassis parameters can be calculated automatically by comparing the output of the wheel sensors to GPS-derived position/velocity information. GPS data are used to continuously calibrate sensor data, ensuring that changes in heading and velocity derived from the wheel sensors will remain accurate. Conversely, navigation data from the wheel sensors is weighted more heavily when GPS information is less reliable, such as within a dense urban environment.

    Wheel Slippage. Tires tend to slip on wet and icy roads. The same phenomenon occurs on gravel surfaces. Actively monitoring for this condition and discarding untrustworthy wheel data for short periods if a better data source is available can significantly mitigate this effect.

     Figure 6 GPS/WSS dead-reckoning accuracy in Chicago
    Figure 6 GPS/WSS dead-reckoning accuracy in Chicago

     

    Road Tests

     

    Because downtown Chicago contains particularly severe urban canyons (see photo), much of the navigation testing outlined in this article occurred within this city. Performance results for a vehicle in this environment are shown in Figure 6 and Figure 7.

    We based the accuracy statistics upon a series of drives conducted throughout a four-hour period and derived the data using an automotive-grade gyro-based truth reference. Note that we discarded some gyro-based truth files due to poor performance.

     Figure 7 2D ground plot (unaided GPS versus GPS/WSS dead reckoning)
    Figure 7 2D ground plot (unaided GPS versus GPS/WSS dead reckoning)

    The unaided GPS fix-density metrics achieved in Chicago are representative of a typical low-sensitivity GPS receiver in a severe urban environment. Note the significant improvement in fix density and 2D-position accuracy achieved through the use of WSS dead reckoning.

    Test Barriers. Although tests similar to those described above provide an excellent venue for collecting system performance data, a number of variables make it impractical to conduct repeated and extensive drive tests in geographically separated cities.

    Limited vehicle availability, varying GPS constellation geometry, unpredictable multipath effects, engineering resource availability, inclement weather conditions, and travel expenses make lengthy field trials by IVNS testers impractical. For these reasons, my company assisted in the development of an automated simulation capability to assess system performance for a wide class of vehicles under controlled multipath, obscuration, and satellite-geometry conditions.

    These simulations can be repeatedly executed for extended periods of time at the developer’s lab facilities. This simulation system is shown in block-diagram format in Figure 8.

     Figure  8 GPS/WSS dead-reckoning automated test setup
    Figure 8 GPS/WSS dead-reckoning automated test setup

     

    Simulations

     

    Procedures for creating a GPS/WSS dead-reckoning simulation are described below.

    First, we equipped a test vehicle with a generic GPS receiver capable of National Marine Electronics Association (NMEA) 0183 message-type output and a roof-mounted antenna.

    NMEA Messaging. We connected a specially designed LAN-data-capture utility to the On-Board Diagnostics level 2 (OBD2) port below the steering wheel to retrieve wheel speed messages, odometer data, steering wheel angle, and transmission status messages. This data-capture utility creates an ASCII file of serial LAN messages interspersed with once-per-second $GGA/$RMC NMEA 0183 sentences and text markers to indicate the rising edge of 1-pulse-per-second pulses.

    After remaining stationary in an open area for three minutes to ensure a 3D fix is achieved, we drove the vehicle for 90 minutes in open sky conditions with minimal obscuration. The test route contains a series of sharp left and right turns, several straight and curved road sections, forward and reverse maneuvers, and a varied speed profile. Upon completion of the test route, we switched off the data recorder.

      LA SALLE ST., downtown Chicago
    LA SALLE ST., downtown Chicago

    Motion Profile. Next, we used the recorded NMEA data file to create a 1-Hz motion profile for the GPS constellation simulator. We loaded the most-current almanac into the 12-channel simulator and initialized the scenario start time to the beginning of the test drive. We then set output power levels to the expected C/N0 values for open sky conditions with attendant radio-frequency (RF) cable loss.

    We then connected the LAN data recorder to the simulation equipment on the test bench and toggled it to "playback" mode. The rising edge of the first pulse from the GPS simulator 1-pulse-per-second output triggers playback to the receiver being tested. The playback tool is designed to maintain synchronization between 1-pulse-per-second updates and corresponding LAN data to within 10 milliseconds throughout the 90-minute scenario.

    Comparative Studies. While the simulation is in progress, the test PC logs the binary once-per-second messages from the receiver under test. At the conclusion of the scenario, we plot the receiver’s latitude and longitude values and compare them with the actual test drive. We conduct additional comparisons between the test receiver’s speed, heading, and C/N0 values, and the actual values observed during the test drive.

    If the test was set up correctly and the equipment operated normally, there should be virtually no difference between the simulated and actual results. Minor discrepancies may be observed due to expected differences in ionospheric and tropospheric modeling, receiver noise figure differences, and ephemeris variations.

    Controlled Testing. At this point, inten-tional multipath, obscuration, and power level variations can be deliberately introduced into the GPS simulator scenario. These effects are created to model tunnels, reflections from tall buildings, and limited sky visibility between intersections — conditions found frequently in large cities.

    These phenomena provide excellent, controlled test conditions for the dead-reckoning filter within the GPS receiver — the filter should weight WSS measurements more heavily when GPS pseudorange residuals are high, C/N0 values are weak, or the satellite signals are otherwise in doubt.

    Although this approach still requires data collection in a vehicle, the duration of the test is reduced to 90 minutes and we can repeatedly change the environmental characteristics of the scenario to model a variety of signal conditions. This method can be used to emulate a city such as Chicago without requiring travel to that location.

    Clean Data. At this point, the reader might ask why the data is not collected in a severe urban environment in the first place. Why is it necessary to collect open-sky data and to add artificial multipath, tall buildings, and tunnel effects later?

    The answer is that when the GPS simulator generates a scenario based on pre-recorded NMEA motion data, it creates the nominal satellite RF signals that correspond with those times and locations.

    Satellite C/N0 values, Doppler values, and code phases are all generated to correspond with that exact vehicle motion profile. If NMEA data were to be collected in a harsh environment such as Chicago, this motion file would be heavily corrupted by the same signal effects mentioned earlier (reflections and obscura). The GPS simulator would not know this, and would simply create the nominal satellite signals corresponding to those corrupted once-per-second locations.

    If we connected the navigation system under test to the simulator and LAN playback utility, the GPS signal characteristics would appear to be optimal throughout the route, interfering with the IVNS’s ability to distinguish good satellite signals from poor ones. This in turn would cause the IVNS to de-weight or to ignore the wheel-speed dead-reckoning inputs at times when their contributions to the solution were especially important. In short, these test results would be invalid.

    Sample simulation results are shown in Figure 9. The test vehicle in this example was a 2005 Chevrolet Equinox, traveling east toward downtown Detroit. Note that a smaller-diameter spare tire was deliberately installed on the right rear wheel prior to the test drive to assess the ability of the dead-reckoning filter to adapt.

     Figure 9 Actual GPS/WSS dead-reckoning data versus simulation playback
    Figure 9 Actual GPS/WSS dead-reckoning data versus simulation playback

    During the simulation, we deliberately switched off the GPS satellite signals prior to the Lodge Freeway tunnel and reintroduced them as the vehicle exited approximately one-half a mile (0.8 kilometer) later. In both cases (actual and simulation), the WSS data (including pulses from the right-rear spare tire) helped the driver accurately navigate throughout the tunnel.

     

    Conclusion

     

    Our customer developed an innovative approach to automotive dead reckoning using WSS data to calculate changes in vehicle yaw and tested the technique in many environments including downtown Chicago and Detroit.

    This augmentation technique will be an effective method to deliver accurate turn-by-turn driving instructions to customers requesting navigation assistance in difficult environments.

    The technique significantly reduced 2D position errors achieved in Chicago compared to unaided GPS, while improving fix density in challenging environments to 100 percent.

    We also have assisted with the development of a creative and reliable approach to thoroughly evaluate navigation performance on a variety of vehicles that requires only 90 minutes of local driving. This simulation capability will reduce test time required to certify system performance and will help identify technical problems well before product launch.

     Further Reading
    Further Reading

     

    Manufacturers

     

    The test drives referenced in this article were conducted using a 12-channel Oncore GPS receiver with WSS dead-reckoning input from Motorola Inc. (www.motorola.com) and a SiRFDrive II GPS receiver with WSS dead reckoning from SiRF Technology, Inc. (www.sirf.com). (Note: SiRF acquired Motorola’s GPS product line on June 1, 2005.) Spirent Communications (www.spirentcom.com manufactured the 12-channel GPS simulator used. Custom development tools manufactured by Danlaw Inc. (www.danlawinc.com) helped retrieve the ABS wheel-speed signals from the vehicle LAN, and reformat and deliver them to both GPS receivers.

    CURTIS HAY served as an officer in the United States Air Force for eight years in a variety of GPS-related assignments. He conducted antijam GPS research and development for precision weapons while assigned to the Air Force Research Laboratory, and managed the GPS Accuracy Improvement Initiative for the control segment while assigned to the GPS Joint Program Office. After separating from active duty, he became the lead GPS engineer for OnStar, a division of General Motors Corp. Hay currently serves as a senior systems engineer for Spirent Federal Systems (www.spirentfederal.com a supplier of high-performance GPS test equipment. He can be reached at [email protected]

    "Innovation" is a regular column featuring discussions about recent advances in GPS technology and its applications as well as the fundamentals of GPS positioning. The column is coordinated by RICHARD LANGLEY of the Department of Geodesy and Geomatics Engineering at the University of New Brunswick, who appreciates receiving your comments and topic suggestions. To contact him, see the "Columnists" section on page 6 of this issue.

     Richard Langley
    Richard Langley
  • Billions per Second

    “Remember that time is money.”

    —Advice to a Young Tradesman, 1748

    For those who take Benjamin Franklin’s admonition very, very seriously, there is now GPS. Network managers for financial institutions recognize that GPS provides the fastest, best, and cheapest source for exact time determination.

    In a white paper, “The Importance of Network Time Synchronization,” Paul Skoog of TrueTime, Inc highlights precise timing’s critical role in transaction processing (see ). Financial institutions from mortgage brokers to stock markets use millions of servers and workstations of all types and functions, networked together and executing a blinding rush of transactions, at rapid changes of value from second to second. In just one instance of everyday fluctuations, the chart above depicts the closing minutes of Intel trading on the New York Stock Exchange stock, November 14, 2001— at an average rate of six transactions/second, and up to 20 per second during intense trading.

    Frequently traders, both business and individual, call their brokering institution to dispute the recorded value of a transaction. In resolving these issues, the time of transaction is critical. Even more critical is the order of the transaction among thousands or millions of others.

    The National Association of Securities Dealers (NASD) now requires its 5,500 members in 82,000 U.S. branch offices to time-stamp all transactions within a 3-second accuracy or better.

    Brokers actually have a higher requirement than that, driven by the need to place transactions in a correct sequence of execution, particularly if there are many nearly simultaneous transactions. Since computer operations happen automatically and quickly, system clock resolution must be less than the minimum transaction composition and transmission time, leading to a need for 5–20 millisecond resolution.

    Computers compute. They do not keep time very well. Based on inexpensive oscillator circuits or quartz crystals, they can easily drift seconds or minutes per day. Many clocks continually drifting apart put network operations at risk.

    The use of GPS as a time-reference standard by financial houses from stock exchanges to offshore banks constitutes another reason the Heritage Foundation advises designating GPS as a critical infrastructure: it underpins the aggregate financial network — and, some might argue, Western society itself.

    Future Stock

    Gerard Lyons, Jim Duggan, and Paraic Quinn at Ireland’s University of Galway are investigating current and possible future applications of distributed time-synchronization to enable transaction timestamping in an agent-based system. They have set up a “Stratum-1” (defined as microsecond-accurate) Network Time Protocol (NTP) server, used by other NTP servers and clients in Europe for time synchronization.

    These researchers state that “tightly-coupled, vertically-integrated supply chains are giving way to more fluid ‘value constellations’ connecting suppliers, intermediaries and customers through real-time information conduits.” They predict the development of “virtual enterprises, temporary networks of companies that come together quickly to exploit fast changing opportunities. An intelligent electronic broker might create a virtual enterprise to execute a single transaction.”

    In this vision of future e-commerce, timing is everything .

    Manufacturers

    The New York Stock Exchange, the World Bank, and other financial institutions utilize TrueTime’s (now Symmetricom) TimeVault product line of NTP servers. Datum (also part of Symmetricom) and Spectracom Corporation, among other companies, also supply NTP servers to financial houses. The University of Galway’s timeserver uses Trimble’s Acutime 2000 GPS synchronization kit.

  • GPS Inside – March 2002

    NovAtel Names Ladd CEO

    NovAtel Inc. of Calgary, Alberta, Canada, appointed Jonathan W. Ladd as president and chief executive officer, effective February 19, 2002. Jim Close, chairman of NovAtel, named Ladd to succeed David Vaughn, who had filled the positions since February 2001. Vaughn will continue in a consulting capacity.

    Ladd recently served as senior vice president engineering and president at Magellan Corporation’s Russian subsidiary, Ashtech A/O, and has held other senior management positions at Magellan.

    NovAtel also appointed Charles R. Trimble to the company’s board of directors. Trimble co-founded Trimble Navigation Limited and served as its president and CEO from 1981 to 1998. He holds four patents in signal processing and several in GPS, and currently serves as chairman of the U.S. GPS Industry Council (USGIC). He has a masters degree in electrical engineering from the California Institute of Technology.

    Spirent’s PPS Simulator: U.S. Subsidiary Targets DoD

    Spirent Communications has announced the formation of a subsidiary, Global Secure Systems, to provide classified GPS simulation products to the U.S. Department of Defense. These will include equipment capable of generating the Precise Positioning Service (PPS) signal and the new military M-code.

    A wholly owned business group of UK-based Spirent plc, Spirent Communications has established Global Secure Systems under a proxy agreement with the U.S. Defense Security Service to enable the company to compete for U.S. government contracts that require classified security clearances.

    Global Secure Systems will be based in Yorba Linda, California, and led by a three-member team with extensive experience in U.S. security and defense operations. Ellen Hall, president and CEO, has more than 20 years experience in the aerospace industry, most recently as vice president of L-3 Communications’ Interstate Electronics Corporation. Former U.S. Secretary of the Navy Larry Garrett will serve as chairman of the board for the new company. Jack Devine, previously deputy director for technology and systems at the U.S. National Security Agency, will also sit on the company’s board.

    Steve Naylor, formerly Spirent Communications’ government sales manager, will serve as vice-president of business development for Global Secure Systems.

    Currently, Spirent Communications claims to hold about 65 percent of the GPS satellite simulator market on sales of products developed by its Global Simulation Systems division development team based in Paignton, Devonshire, UK, and headed by Peter Boulton.

    Spirent currently supplies unclassified simulators to the GPS Joint Program Office (JPO) and other U.S. defense agencies, which then enhance the equipment with classified hardware and software. The Global Secure proxy agreement will allow the company to build and deliver complete PPS-capable equipment, says Hall.

    Spirent Global Simulation already markets PPS-capable products to European members of NATO who have signed a memorandum of understanding with the JPO. Global Secure hopes to have a pseudo-M-code simulator available soon and a full M-code simulator on the market within the next year or so.

    GPS Rides Cable Cars, Olympic Trains

    The city of San Francisco has contracted with NextBus Information Systems of Emeryville, California, to provide real-time arrival information for its public transit system’s (MUNI) fleet of a thousand-plus buses and trains. Even San Francisco’s 19th-century cable cars will carry the GPS-based system. NextBus systems track selected routes in 20 U.S. public transit systems, but San Francisco now becomes the first city to equip its entire fleet. The $9.6 million contract calls for installation on all lines within five years, and includes 430 electronic information signs at transit stops across the city.

    Each bus or train will carry an AirLink Pinpoint unit combining a 12-channel Conexant Jupiter 11 GPS receiver with a cellular digital packet data (CDPD) modem to track and transmit location, vehicle ID, current route assignment, and other data to the NextBus information center. (SiRF Technology acquired Conexant’s GPS chipset business in July 2001 and now supports the Zodiac chipset within the Jupiter receiver. Conexant continues to make the Jupiter board.)

    NextBus estimates vehicle arrivals at stops along the line by factoring in actual position, intended stops, and typical traffic patterns.

    Passengers can view vehicle location and estimated arrival times on electronic signs at transit stops, on wireless devices such as PDAs and cell phones, and at the NextBus website. They can reduce waiting times and exposure to weather, and receive web alerts when their bus reaches a certain distance from home or office. A 2001 Delaware trial increased route ridership by 13.5 percent. The system also increases transit managers’ ability to respond to unexpected events in real time.
    NextBus operated a three-month trial run in San Francisco in summer 1999, along the #22 Fillmore route. After positive rider response, the city asked NextBus to extend the service to metro trains and to include transit information on the Internet as well as at the stops.

    Winter Olympics. The million-plus train riders at the 2002 Olympic Winter Games in Salt Lake City rode to their events informed by a tracking system from GeoFocus, of Boca Raton, Florida. Hardware installed by Utah Transit Authority on its light rail cars includes two Ashtech G8 receivers on each of 33 cars, plus 24 “rovers” aboard loaner cars borrowed for the Olympics. The system provides audio and text messaging at 20 stations, notifying passengers when the next train will arrive.

    Geofocus, a Sumitomo Corporation subsidiary, also installed its TrainTrac system on 264 trains serving 11 commuter lines in the Chicago METRA System in December 2001. These units incorporate Trimble Lassen SK2 receivers.

    Chinese GPS Group

    The International Association of Chinese Professionals in Global Positioning Systems (CPGPS) is a new non-profit professional organization whose members are Chinese and other interested professionals from academic institutions and industrial sectors in Asia, Australia, Europe and North America.

    The association’s electronic publication, the Journal of Global Positioning Systems, will deliver research findings, report progress, and exchange ideas. The CPGPS will also develop research programs and establish a newsletter for advice, consultation and debating of GPS issues. For further information see the organization’s web page www.cpgps.org.

    IEC SAASM, Missile Defense

    The Interstate Electronics Corporation (IEC) division of L-3 Communications has introduced its TruTrak 12-channel Selective Availability Anti-Spoofing Module (SAASM)-based GPS receiver for military applications. TruTrak meets high-G platform requirements but is also configurable for range, avionics, or handheld navigation platforms. The company states C/A and P(Y)-code signal acquisition of less than three seconds. Derived from IEC’s projectile receivers, it may be operated tightly coupled to an optional 6-DOF external inertial measurement unit, allowing very narrow bandwidth tracking in the presence of intentional or incidental interference.

    TruTrak will track up to 12 satellites simultaneously. (The GPS Receiver Survey in the January issue of GPS World erroneously identified it as a 6-channel receiver.)

    Meanwhile, IEC has also received a three-year, $6 million contract to support the Ground-based Midcourse Defense Segment (GMDS) under the U.S. Army Strategic Missile Defense Command. IEC will supply 30 digital GPS translators and two GPS translator processors, engineering, logistics, and field launch support. The GPS translator units will support GMDS by providing post-mission flight measurement and range safety tracking of simulated warhead and booster stages of interceptor kill vehicles.

    NEC Puts SiRF in Driver’s Seat

    SiRF Technology and NEC Electronics (Europe), based in Dusseldorf, Germany, have announced a licensing agreement to integrate SiRF’s GPS technology into NEC’s integrated circuits designed for the automotive marketplace. The partnership targets oncoming multimedia navigation systems in standard as well as luxury cars.

    NEC will integrate the SiRFstarII GPS baseband core to location-enable its automotive products, the first of them a low-cost navigation companion chip, incorporating an ARM7TDMI core with on-chip GPS and signal preprocessing capability for a host central processing unit. The companies plan sample chip availability in the third quarter, with volume production likely by the end of the year. NEC also plans to develop non-automotive applications based on the SiRFstar technology.

    Z/I, Applanix Units Score

    Aerial photography provider Simmons Aerofilms has selected the POS Z/I 510 position and orientation system with inertial measurement unit from Z/I Imaging, the joint venture of Intergraph Corporation and Carl Zeiss. The system is Z/I’s OEM version of the Applanix POS/AV-DG, with NovAtel’s Millennium GPScard.

    Integrating inertial sensors, GPS, and post-processing software, the system measures the camera’s absolute position and orientation angles of each image with stated accuracy of 5–10 centimeters and 20–30 arcsec respectively. The unit allows direct georeferencing of aerial photographs without aerial triangulation and with minimal ground control, reducing overall costs.

    Shaanxi Meihang Digital Surveying group, China’s largest surveying, remote sensing, and mapping enterprise, has chosen Z/I’s Digital Modular Camera (DMC) for urban construction, field archaeology, disaster investigation, and other applications. The differential GPS-equipped DMC uses eight synchronously operating cameras to mosaic converging panchromatic images for reported ground resolutions better than two inches. The DMC uses a NovAtel OEM4 receiver for position and a 12-channel Garmin receiver for navigation.

    CSI Ag, GIS Entry

    CSI Wireless has launched its SERES GPS receiver/antenna combination for precision agriculture, geographic information systems (GIS), and mapping applications. In addition to GPS, the unit uses dual-channel tracking to receive signals from the Wide Area Augmentation System (WAAS) and the European Geostationary Navigation Overlay System (EGNOS). The unit’s 12-channel Zarlink receiver reportedly delivers sub-meter horizontal accuracy with differential GPS (DGPS). Measuring 4.1 32.7531.1 inches, SERES can function as the positioning element of a precision guidance system or as a backpack-
    mounted unit providing data to a hand-held unit for GIS or mapping.

    Leica GeoMoS

    Leica Geosystems has introduced its Geodetic Monitoring System (GeoMoS), a software package for precise deformation monitoring and analysis. Designed to support single-sensor monitoring stations or multi-sensor networks for bridges, tunnels, dams, mines, volcanoes, and high-rise buildings, GeoMoS integrates data from GPS receivers, strain gauges, and meteorological sensors into a single network. It monitors real-time movements and issues alerts of any movements beyond pre-defined tolerances.

    The European Navigation Conference (GNSS 2002) takes place May 27-30 in Copenhagen, Denmark, hosted by the European Group of Institutes of Navigation and the Nordic Institute of Navigation. Conference themes include GNSS status, architecture, and implementation; Galileo; interoperability and standardization; navigation infrastructure and development; system applications and user experiences; political and institutional issues; and future developments. For details e-mail <[email protected]>, or see web site.

    The Ninth GNSS Workshop (2002 International Symposium) has issued a call for papers for a conference scheduled November 6-8 in Wuhan, China. Themes include GPS/GNSS status, modernization, and augmentations; navigational and positioning infrastructure; receiver and antenna technology; and applications in range of fields. Email abstracts to <[email protected]>, or fax them to +86-27-87876495-13, before April 30.

    Trimble, located in Sunnyvale, California, announced total revenue for 2001 of $475.3 million. Fleet and Asset management revenues were 12 percent, Components Technologies 12 percent, Agriculture 5 percent and Portfolio Technologies 7 percent. Trimble raised $46 million in a private equity placement in 2001, sold its airline operations, and acquired the Spectra Precision Group and software developer Tripod Data Systems.