Qutoes of the Quarter
“The civil aviation world is now fully aware (that) GPS ‘sole means’ naviga-tion is a dead issue. GPS is a supple-mental system. VOR/DME, DME/DME, ILS and MLS can be used as stand alone systems and can be used without GPS. They are primary systems.” Consultant and former FAA Administrator Langhorne Bond.
“It’s time now for the FAA to elimi-nate the ‘paralysis of analysis’ and get on with the (WAAS) program. It’s time to set the course for satellite naviga-tion ...” Dennis Roberts, VP, Aircraft Owners and Pilots Association.
“Among all the economic stars gen-erated by technology sectors over the past decade, GPS has become a genuine superstar.” Dr. Neal Lane, head of White House Office of Science and Technology Policy.
Congress Slashes Funding for GPS, NDGPS and FAA
Fiscal 2000 was not a very good year for GPS civil users on Capitol Hill.
Congress zeroed out all funding requested by the Administration for the Department of Transportation’s (DoT) share of GPS modernization for civil users, a total of $17 mil-lion, part of the FAA budget. Lawmakers also cut in half the funding requested by the Federal Railroad Administration for the National Differential GPS system (NDGPS), cutting it from $10.4 million to $5 million for fiscal 2000, and moving it to the Federal Highway program. Despite efforts at further damage control, Congress whacked $30 million out of the FAA’s request of $110 million for the GPS-based Wide Area Augmentation System (WAAS). And budget cutters didn’t spare the companion Local Area Augmentation System, killing the $4 million sought LAAS. The Pentagon, in contrast, got most of what it requested for GPS operations and capital improvements, with the exception of one item: $31.8 million for advance pro-curement of one more Block IIF spacecraft, which Congress deleted.
“They clocked the GPS civil side,” one mournful observer put it succinctly. “We’re not getting the message across. We will have to rely on the military to carry the load for the time being.” At the ION GPS ‘99 conference in September, keynote speaker Neal Lane, Assistant to the President for Science and Technology, lamented the loss of modernization funding. In strong terms, Dr. Lane said, “We will miss a window of opportunity that could delay GPS modernization by up to five years and significantly increase the cost of civil GPS enhancements. These delays will create new opportunities for others..., reducing the markets for GPS-based products and services. Hundreds of thousands of U.S. jobs, billions of dollars in sales worldwide, and U.S. leadership in a critical information technology are at stake. But so far, these arguments have not convinced Congress to act responsibly.” In the same timeframe, the GPS Interagency Advisory Council (GIAC) unanimously agreed to a statement warning that the Europeans may preempt the L5 frequency part of the modernization program, if the United States fails to use it. The GIAC letter, signed by Chair Charles W. Challstrom, and sent to Dr. Lane, said the European Union was considering use of the L5 frequency of 1176.45 MHz for the Galileo system and in-orbit testing by late 2003. “GIAC is concerned that ... GPS will be forced to demonstrate a non-interference approach before L5 can be implemented on GPS (because) Galileo will be the existent system on that spectrum,” Challstrom wrote. “This could further delay, or possibly prevent, implementation of L5... .”
Never Say Never
As Congress prepared in November to leave town for the year, DoT had several fallback options to attempt restoration of some funding losses. It could look to the year-end reconciliation bill, an annual omnibus spending bill where Congressand the Administration reconcile some differences that they failed to consider when separate appropriations bills passed earlier. Or agency officials could seek to restore funding in a sup-plemental money bill, probably in the next ses-sion of Congress in January. The most likely action, however, may be to reprogram funds from within departments; this may find the greatest applicability to the modernization program, and LAAS. Further, the Administration will return next year with FY2001 DoT budget requests for GPS modernization (an estimated $40 million proposal is said to be before the Office of Management and Budget now), as well as for NDGPS and for WAAS/LAAS.
Congress expressed various reasons for making the FY2000 cuts. In the cases of the modernization and NDGPS funding requests, it chiefly cited problems of having one agency carry the budget burden for a program that actually serves multiple agencies, a persistently vexing issue in federal budgeting structures. But lawmakers merely voiced the age-old complaint; they didn’t suggest how interagency funding for the programs could be accomplished. Nor did the Administration offer in a timely manner a method for other agencies to help pay for the programs, as requested last year by Congress. Meanwhile, personnel were being sought to staff a new executive secretariat of the Interagency GPS Executive Board (IGEB), part of a major organizational move designed to define and strengthen the role of GPS in the federal government. The permanent new office will provide a centralized point for interagency policy on GPS. Stephen Moran, former senior advisor at the White House Office of Science and Technology Policy, withdrew his name to head the office to accept a position with Raytheon Corp. Beyond this, GPS backers informally are stepping up efforts to conduct informational and educational initiatives to alert lawmakers to potential foreign competition, to better inform Congress of the mounting benefits of GPS to the national economy, and the need for Congress to support progressive programs that enhance the utility of the global GPS system for both civil and military users, worldwide.
Congressional Fellow Being Sought, Student Aid Discussed, ION GPS '99 Reviewed
With arrangements for establishment of a Congressional Fellow Program well underway, the ION is now actively soliciting nominations for the first Fellow who will receive ION support for work in science and technology on Capitol Hill.
At a meeting of the ION Strategic Planning Committee in Nashville on September 16, a goal was set to make a final selection by June 2000. Richard Greenspan is heading the selection committee. ION Headquarters is circulating a letter to all corporate members to solicit candidates; it was suggested that it might also be attractive to a professor on sabbatical.
Ken Holland, chair of the Congressional Fellows Committee, said a final report on the program would be made at the January 2000 ION Council meeting. Meanwhile, Holland reported he presently was modeling the program along the lines of similar programs at the IEEE and AIAA. He anticipated a salary for the first Fellow of $4,000 per month, and an additional $2000-to-$3000 for moving expenses. Holland is providing Greenspan with selection criteria.
For the successful candidate, there will be a training course hosted by the American Association for the Advancement of Science in Sep-tember 2000. The fellowship would officially start in January 2001.
At a meeting of the Satellite Division Executive Committee in Nashville on September 17, Phil Ward provided a progress report on the program to pay expenses for establishing GPS as the instrumentation standard for the National Aeronautical Assn. (NAA). The NAA runs speed trials and certifies aviation speed records.
The Division so far has allocated $10,000 to subsidize the expenses of graduate students and to help acquire GPS equipment for the NAA project, and an additional $20,000 may be needed in the future.
In other actions, Sally Frodge, ION GPS ‘99 program chair, noted that student paper win-ners liked being mainstreamed into the regular technical sessions at the conference this year for the first time, rather than being categorized separately as student presentations. Ron Hatch, Satellite Division chair, said a proposal is being prepared by Frodge, Elizabeth Cannon and John Lavrakas to produce GPS lesson modules for classroom use; it will be considered at the next meeting of the Satellite Division Executive Committee in January. Lisa Beaty, ION director of operations, reported that, in response to a Division initiative, the resumes of some 20 stu-dents were bound in books and distributed to exhibiting companies at the conference that requested them. A decision on a proposal to hold a job fair for students, however, was post-poned, pending further consideration at the next meeting in January.
ION GPS ’99 Reprise
In all, the ION GPS ‘99 conference in Nashville in September was successful, according to reviews during the Satellite Division Executive Committee meeting. Program Chair Frodge said some sessions had standing room only and that many persons asked to be session chairs next year. Larry Hothem is program chair for the next meeting in Salt Lake City in 2000; Frodge will be general chair. Hothem, GPS publicity chair this year, said he felt some progress had been made, compared with previ-ous years, under the Division’s new public rela-tions program.
At the Strategic Planning Committee meet-ing on September 16, it was suggested ION look into ideas for sessions in the future on machine automation, GPS applications in cellular tele-phones, in precision farming, as well as spon-soring a session on Congressional policy and funding and on ultra wide band applications.
From the Editor
A letter from Brig. Gen. Robert A. Duffy (USAF, ret.) to the ION seeks to set the record straight on some of the numerous military contributions to navigation in space. Duffy is a former ION president, and former president and CEO of the Charles Draper Laboratory, Inc. He was prompted to write by ION Historian Marvin May’s “Milestones” column in the spring issue of this Newsletter. The letter, in part, follows.
A sociologist might point out that recent technology advances reflect the combined efforts of many individuals and companies to such an extent that one cannot identify individual contributions as easily as in the list of pre-war accomplish-ments. Moreover, one could argue that we are too close to events to recognize what will be the lasting accomplishments of the last 50 years. This being said, I would like to supplement Marvin’s list with the following observations.
Recalling that the need to navigate submarines without reference to celestial measurements was the stimulus for much of the technology advances, the development of stable vertical references under sponsorship of the ‘Gun Club’ of the Naval Ordnance fraternity ... led to the magnifi-cent long-term underwater navigation sys-tems first demonstrated by Stark Draper, Joe DeLisle and others at the MIT Instrumentation Lab.
This capability was implemented operationally by Zike Barrow’s people at Sperry on Draper’s design. Autonetics followed with an adaptation to the submarine environment of their design of the auto navigator for the NAVAJO aerodynamic missile’s guidance system developed under Air Force C and N Lab sponsorship that was led by Frank Banta and John Hepfer. John Moore’s group at the North American Aviation Co.’s Aero Physics Lab played fundamental roles in the applica-tion of gas bearing instruments to both fighter auto-navigators under Henry Singleton, and cruise missile guidance. These culminated eventually in the superb guidance and control equipments for Minuteman missiles...
The Apollo program and follow-on astronautical systems developments were strongly influenced by Draper himself and at times more by his disciples. Cliff Duncan, a young Navy officer who earned his Doctorate in Instrumentation under Draper at MIT, led a NASA group responsible for the Apollo GN&C development and operational support during the missions to the moon.
Milt Trageser, a brilliant inventor on Draper’s staff at MIT, had sold the Air Force on an idea for the Mars Probe in the mid-1950s, and had fabricated a design with a complete stellar-aided guidance system (an AF classified contract). When NASA aired its plan for Apollo, Draper himself proposed a design for navigating a manned capsule to the moon, and return, utilizing the work pioneered by Trageser as a basis. Draper proposed that he would accompany the equipment to be sure it worked as he intended it should.
The first contract issued by NASA on the Apollo program was awarded to MIT for the development of a guidance and control system as Draper proposed. Dave Hoag, a former ION president, adapted the Navy’s Polaris guidance hardware to the Apollo requirements, and Hal Laning and Dick Battin, both ION Thurlow Award winners, devised the guidance laws to be implemented in the on-board computer and married to NASA’s mission control radio network. The extraordinary record of manned space flight safety and unmanned exploration of the solar system rests on these pioneering activities.
I am sure that ION members remember other pioneering achievements with at least as much awe as I have attempted to convey. I wish that there were a means to do justice to them all.
It was signed, very truly yours, Robert A. Duffy.
A History: What Makes GPS Tick
Dennis Galvin, chief projects engineer for satellite programs at Boeing, finds that “advancements of space components in the 1960s, particularly in the size and weight reduction of atomic clocks, provided the enabling technology that allowed the DoD to proceed with the space-based proof of concept of radionavigation.”
But atomic clock technology is but part of the story. In a paper at the GPS ION ‘99 conference, Galvin traced milestone events in the history of the GPS space segment.
The Block I spacecraft, built by Rockwell, were the proof of concept vehicles, he noted. Rockwell won the contract over RCA in 1974 for eight spacecraft, later raised to 12. (Rockwell subsequently won the contract for 28 production Block II/IIAs).
Initially, Rockwell gathered many of the engineers who had built the second stage (S-11) of the Apollo launch vehicle to work on the GPS project, under the leadership of Richard Schwartz. “Some of the enabling technologies that Schwartz brought from S-11 were various structural techniques, such as bonding, honeycomb structure and materials processing,” Galvin relates.
He outlined in his paper some of the unique features that contributed in the design and development during 1970s to the success of the space segment, as follows.
Navigation Subsystem —
Further, a design feature that shapes the radiated power almost uniformly over all regions of the earth’s surface allows users viewing a satellite low on the horizon to enjoy the same received power as a user directly under the satellite. Introduced by Rockwell in the Block I, the same antenna design is used on the Block II/IIAs and the current Block IIRs.
Atomic clocks, then an art more than a science, are at the heart of the navigation subsystem. Schwartz found a small company, Efratom, Costa Mesa, CA, whose founder, Ernst Yeager, had developed a commercial ground-based rubidium clock, Galvin recounts. Rockwell’s Autonetics Division removed the physics package of the terrestri-al clock, modified it, wrapped it in new elec-tronics, repackaged it and qualified it for a space environment, according to Galvin. Cesium later was added to the last four Block I satellites.
Attitude Control Subsystem —
Scientists at JPL noted a small navigation change in the Block IIs as they exited the sun’s shadow twice a year during eclipses. To compensate, GPS managers built in a small continuous yaw maneuver, known as a noon turn, whenever a satellite is in shadow, the author explained.
Thermal Subsystem —
Satellite Hardening —
The paper dealt with other factors that helped frame the success of the GPS constellation, including those dealing with power subsystems, testing, and others. In sum, Galvin said GPS satellites, based on original requirements, have succeeded in providing twice the accuracy, twice the power and twice the life during this century.
Snapshot on Spectrum
An Update on Two Key Spectrum Issues
By Sally Frodge
Spectrum is an extremely valuable resource — it is worth the time it takes to assure that adequate spectrum is in place to support vital systems such as GPS. Debate on spectrum issues— even on domestic issues — most likely reaches international audiences and can have impact on decision-making both within the U.S. and abroad.
Spectrum engineering and policy is a challenging area. Many of the real issue points are steeped in decibels (dB) and equations — not everyone’s forte. Yet, it is critical to understand the relationship of these issues to the GPS industry, an industry that has grown exponentially over the past decade through use of GPS and its radio frequency signals. Decisions on spectrum issues can and will affect not only how business is conducted but may possibly impact the bottom line of a company.
Protection of the GPS spectrum is not something that can be taken for granted; it needs to be actively worked. The Federal Aviation Administration (FAA), RTCA, Inc., Airline Transport Assn. (ATA), some airlines and others who have been particularly active protecting the civil spectrum for aviation use have provided a significant benefit to the non-aviation community — the value of which is probably very difficult to fully appreciate. In addition, the GPS Industry Council, various companies, and some within academia have also been extremely active in protecting GPS spec-trum to the extent of filing comments with the Federal Communications Commission (FCC). One point about spectrum protection is very clear — it is an enduring issue that requires constant vigilance. Competition for spectrum is very acute and is only growing in intensity.
Though many current spectrum issues potentially involve or affect GPS, this is an update on just two areas: ultra wide band (UWB) technology and its interference potential to GPS; and a brief synopsis of GPS issues coming before the International Telecom-munications Union (ITU) World Radio Conference (WRC). On the horizon are many other spectrum issues such as spectrum auctioning, Enhanced 911 services, other sources of in-band, out-of-band or near band interference, standards development, L5, et cetera. The over-all health of the industry is certainly in part reliant upon those who are actively working these and other spectrum issues.
Ultra Wide Band Technology and Potential for GPS Interference.
Recently, the FCC granted waivers to a portion of the Part 15 rules to three manufacturers of ultra wide band (UWB) technology. Further information on waivers can be obtained at www.fcc.gov/oet/waivers/. Some UWB technology can interfere with the acquisition and tracking of the GPS signal. Note that some implementations of this UWB technology span over 200 MHz of spectrum — right across L1, L2 and the proposed L5. It is anticipated that the FCC will take action within the next year to address this issue, most likely within a rule-making process.
It is necessary for the GPS community to characterize the potential levels of interference with credible data in order to have the regulatory process move forward in an informed manner. The application areas these UWB devices hope to fill are quite diverse. Some examples are collision avoidance for cars and other vehicles, detection of anomalies in bridges and road surfaces, detection of bodies in buildings, communications as well as others. Since these could become quite widespread and some UWB devices are known to cause interference to GPS, it is critical that this issue get appropriate attention.
The upcoming International Telecommunications Union (ITU) World Radio Conference (WRC) is scheduled for May-June, 2000 in Istanbul, Turkey. The ITU is the international regulatory body for spectrum management. Each member (that is, each paid up member nation) has one vote.
Prior to each WRC, a Conference Preparatory Meeting (CPM) is held to summarize the agreed upon preliminary views on all agenda item issues that will be discussed at the upcoming WRC. The language in the CPM text is very important since it may be the only background information some WRC delegates receive on certain issues. The meeting to finalize the language on the preliminary positions for WRC-2000 was held during the last two weeks of November in Geneva, Switzerland. A great deal of work was done to negotiate the appropriate CPM text language on not only the GPS issues but for other spectrum issues of importance as well. Even though it is critical to get the appropriate language in the CPM text, it represents only preliminary views — meaning these views can change even up to the last minute on the floor of the WRC debates. The key issues for GPS that will be discussed at WRC-2000 are discussed below.
MSS and GPS L1 Sharing Issue (Resolution 220), WRC-97 Agenda Item 1.9.
During the last WRC in 1997 (WRC-97) a new allocation was sought for mobile satellite ser-vices (MSS) from 1559-1567 MHz. The debate at WRC-97 led to “Resolution 220”. It called for a period of study to determine the feasibility of GPS and MSS sharing of 1559-1567 MHz through reallocation of that band to MSS on a Co-primary basis. Through multiple international technical studies, it was determined that sharing is not feasible. This is good news for anyone interested in the success of a Global Navigation Satellite System (GNSS). GPS is an accepted component of the GNSS per the Inter-national Civil Aviation Organization (ICAO).
The conclusion that sharing is not feasible was based upon international studies determining that MSS interference can occur to GPS navigation signals, thus potentially degrading safety-of-life aviation services using the GPS L1 signal. Clarification of the bandwidth for civilian applications (±20 MHz, registered band-width ±24 MHz) and pseudolite studies in the lower portion of the band were useful in driving to this conclusion. The pseudolite studies repre-sent the larger issue of expansion of radio navi-gation satellite service (RNSS) systems in the band and future evolution of GPS.
Nevertheless, the issue is still very much alive — INMARSAT’s withdrawal of interest in this spectrum does not stop the ITU action. Since WRC-97, a great deal of work has been accomplished on this particular issue. This has raised awareness and has gained support to not share the GPS L1 spectrum with MSS. INMARSAT-UK initiated this proposal at WRC-97. The subsequent withdrawal of interest by INMARSAT in this spectrum has caused some to believe the issue is settled. This is not so. Even though INMARSAT has withdrawn support for this proposal, the ITU process is in motion. CEPT and APT, the European and Asia-Pacific communications consortiums, respectively, supported some form of Resolution 220 at WRC-97. Should CEPT or APT withdraw their support for Resolution 220 this year, it certainly would be significant news; nonetheless, the issue would still remain open until the vote is finished at WRC-2000 suppressing Resolution 220.
Space-to-Space Allocation, WRC Agenda Item 1.15.2.
The United States is seeking to add a space-to-space allocation to the existing allocations for the bands containing L1 and L2. These allocations would support existing space operations and promote growth in space-based activities. These allocations move towards enabling future automation for earth-orbiting satellites that would result in cost and performance benefits. Growth of the space industry and how it is to move forward will be a dominant part of the next decade’s spectrum debates.
L1 and Fixed Services
L1 and Fixed Services allowed in the 1559- 1610 MHz band by footnote, WRC-97 Agenda Item 1.15.3. Footnotes allow services other than RNSS in the 1559-1610 MHz band on a secondary basis in 25 countries and on a primary basis in 44 countries. This agenda item seeks removal of the fixed services from the 1559-1610 MHz band. Removal will allow that country full use of GPS L1 services. This effort has gone well and many of these footnotes will be removed. The U.S. seeks support in removing unnecessary footnotes from the 1559-1610 MHz band to make way for unrestricted aviation use of GPS as part of the pro-posed Global Navigation Satellite System (GNSS) of the near future.
The Proposed GPS Civil Signal for Safety-of-Life Applications, WRC-97 Agenda Item 1.15.1: GPS is almost a quarter century old. The U.S. is moving ahead to modernize the system. Part of that planned effort is the inclusion of Coarse Acquisition (C/A) code on the L2 frequency and addition of a new civil frequency, L5, the latter centered at 1176.45 MHz. To better meet the civil requirements for a modernized GPS, the proposed L5 signal is at much great power than L1 (+6 dB) and has a greatly improved code structure over C/A-code. The U.S. is seeking an RNSS allocation to accommodate L5. Extensive technical analyses have shown L5 will not interfere with any existing systems in the 960-1215 MHz Aeronautical Radio Navigation Service (ARNS) band. A number of inter-related factors were integral to the selection process. It is important to note, however, that in today’s environment there is considerable pressure on spectral resources, and there is no frequency band lying fallow that is suitable for RNSS use. L5 reflects the results of many discussions and the work of many groups, including the government, academia, industry and others such as RTCA. In addition to higher power and improved code structure, L5:
This requirement, consistent with the objectives of the ICAO, would provide GPS L5 with regulatory protection similar to that existing at GPS L1, and ensure a stable, controlled, worldwide environment for GNSS operations.
Discussions for the selection of L5 considered such factors such as satellite vehicle constraints, no-interference and minimizing impacts to existing systems, operational environment considerations, aviation use versus non-aviation use, and others. After considerable trade studies and technical analysis and consideration of frequency bands from 900 MHz to above 5 GHz, 1176.45 MHz was determined to be the best candidate.
Again, the debates on these issues will continue with this round of discussions culminating at the upcoming WRC-2000 in Istanbul. Until WRC-2000 is over, the outcome on these issues will not be known; they are open agenda items. Spectrum protection requires sustained vigilance. Spectrum managers and engineers are the front lines of any spectrum-based system like GPS. Their efforts, and all who support them, are critical to the success of any spectrum-based system.
Author Sally Frodge is with the U.S. Department of Transportation, Office of the Assistant Secretary of Transportation Policy, Radionavigation and Positioning staff.
Secrets of the Swallows of San Juan Capistrano
What shape is the shadow tip path becoming at the swallows departure from Buenos Aires?
A: concave up
B: concave down
C: straight line
First you must know that the swallows return to San Juan Capistrano yearly at spring. The shadow tip path cast by any prominence generates a family of conic curves during the course of the year and is concave up during the winter degenerating to a straight line on the verequinox and becoming concave down during the summer (the reverse is true in southern hemisphere). At spring or the fall, the plane containing the axis of the Earth is perpendicular to its orbital plane and its radius to the Sun. At this time there is no tilt toward the Sun and the shadow tip path curve has degenerated to a straight line. The rest of the year there is a varying tilt component toward the Sun that results in a unique conic curve (hyperbolas, parabolas and ellipses) as seen in Figure 1. Figure 1 illustrates the conic curve that is generated depending upon the relationship of the declination of the Sun and the latitude of the observer or the declination of the Sun and the inclination of the receiving surface to the horizontal plane.
The shadow tip path geometry is a function of the declination of the Sun and the latitude of the observer. Figure 2 depicts a cross section of the Earth with the Sun S on the observer’s meridian. The observer’s zenith is at Z and his latitude L is arc QZ. If the polar distance of the Sun (90°-d) is equal to the observer’s latitude, the shadow tip path will be a parabola; at higher latitudes it will be an ellipse and lower, a hyperbola. In any event these curves flatten to a straight line as the equinox approaches. The case shown illustrates the Sun at the summer sol-stice with declination of 23.5° and the lati-tude of the observer 67.5° (when the latitude equals the Sun’s polar distance).
The shadow tip path cast by the Sun resulting in a hyperbo-la is shown in Figure 3. The locus of the shadow tip path of the Sun was recognized as the basis of a sun dial and calendar early in history. Additionally the properties of the shadow tip path can be used as the basis for a solar compass as well which is depicted in Figure 4. The solar compass depicted allows the observer to determine true North and the local apparent time. The solar compass is held level and rotated until the tip of the shadow, cast by the raised index, is touching the day of the year curve shown on the face of the compass enabling the observer to read the direction of true North and the local apparent time.
The answer is C: a straight line.
Dorrie, Heinrich. 100 Great Problems of Elementary Mathematics: Their History and Solution. New York: Dover Publications, Inc. 1965.
Rohr, Rene. J. Sundials, History, Theory and Practice. Toronto: University of Toronto Press, 1965.
ION Annual Awards Nominations Open
Members are encouraged to submit nominations now for one or more of the prestigious Annual Awards given by the ION for excellence in navigation. The awards are:
Official nomination forms, along with brochures on the background and purpose of each award, are available from the ION national office by phone, 703-683-7101, or e-mail: email@example.com. Nominations must be received by February 23, 2000.
The awards and accompanying engraved bronze plaques will be presented at ION’s 56th Annual Meeting, June 26-28, 2000 in San Diego, California. ION urges you to participate in the nomination process so that a representative group of deserving individuals from the navigation community will receive appropriate recognition.
In addition to the above awards, the winner of the Samuel M. Burka Award — for outstanding achievement in the preparation of papers advancing navigation and space guidance — chosen by the editorial panel of ION’s journal, NAVIGATION, will be honored.
ION GPS '99 Keynoter and Plenary
GPS Satellites Outlive Design
Brig. Gen. (S) James Armor told attendees at the ION GPS ‘99 conference in Nashville that the Air Force has extended the life expectancy of the Block IIA satellites in the GPS constellation from an original 7 years design life, to 10.5 years. “And I wouldn’t be surprised if it were extended again,” he added.
Armor, outgoing Program Director for the GPS Joint Program Office (JPO) was one of the speakers at the plenary session opening the conference held Sept. 14-17. Keynote speaker, Dr. Neal Lane, head of the White House Office of Science and Technology Policy, recounted the numerous societal contributions of GPS over the past 30 years, and spoke hopefully of the improvements to come under the modernization program.
Members of the Plenary panel, moderat-ed by Dr. Scott Pace, Rand Corp., included Daniel Salvano, FAA, John Ryan, Air Tran-sport Assn. of America, Roderick Van Dam, Lufthansa, Joseph Canny, U.S. Department of Transportation, John Bowdler, Australian Department of Transport, and Armor.
The bad news of longer satellite lifetimes, Armor conceded, was the fact that the planning date for the launch of the first Block IIF has been moved out to 2005. “The good side is it does give us a little more time to finish the upgrades to our control segment,” he continued, “but it does delay ... our modernization deployment.”
Armor said the Block IIR satellite damaged by rain — “what we call Wetsat” — is being repaired, and “hopefully, we’ll fly it sometime.” On modernization, Armor said the proposed new L5 signal design produced by the RTCA is “a gang-busters signal. It’s really terrific.” There still remains a chance, he said, that some modernization features can be incorporated in the last nine of the Block IIR series.
Dr. Lane looked at the future, then shifted to sharp criticism of congressional actions that cut modernization funding for fiscal year 2000. “In the future, we will see GPS receivers smaller than credit cards, and affordable enough for use in almost any vehicle, cell phone, or pocket phone,” Lane declared. “With every square yard on earth measured and labeled with an address, and with computerized databases available that give latitude and longitude as well as address, it’s conceivable that no one will ever again need to ask directions.”
Addressing the audience on modernization, Lane said: “Scientists and engineers like you constitute one of the largest, most valuable, yet least-heard constituencies in America. Our elected representatives need to understand that investments in the future of science and technology are investments in the future of our country, and are investments that Americans are willing to make.”
In his valedictory, Armor called the annual ION Satellite Division conference “a tremendous forum for us to exchange ideas and learn, and frankly, be inspired by all the commercial creativity displayed here and sci-entific and engineering innovations that we see presented.
“I would encourage all of you to hold the vision, and in fact demand the vision of a single world standard for global positioning and timing and know that you are changing the face of civilization.”
Spilker Wins Kepler Award
Dr. James Spilker Jr. received the coveted Johannes Kepler Award for his outstanding contributions to satellite navigation at the climax of ceremonies during the ION GPS ’99 conference in Nashville in September.
Spilker, a founder and former chairman of Stanford Telecom, was instrumental in the design of the current GPS modernization package, placing a second C/A signal centered on the L2 frequency, and creating a third more powerful civil signal called L5 at a proposed new frequency of 1176.45 MHz.
Earlier, Spilker conceptualized and designed the CDMA signal structure for GPS that is in use today. He is author or co-author of two widely used books on digital communications and GPS technology, and author of numerous papers on satellite systems, spread spectrum and navigation technologies. Spilker got his Bachelors, Masters and Doctors degrees from Stanford. He is a Life Fellow of the Institute of Electrical and Electronics Engineers, a Fellow of the ION and a Member of the National Academy of Engineering.
For Four Days Nashville Was Center Of Globe
The four-day ION GPS ‘99 conference, the largest in terms of sessions and papers presented, drew attendance from more than 30 countries, and SRO crowds at some of the more popular panel discussions. The 12th International Technical Meeting of the ION’s Satellite Division assembled for the second year in a row in Nashville — the self-styled foot-stompin’ country music capital of the world — Sept. 14-17.
Total attendance, subject to post-processing, reached 2035, slightly higher than the previous year. More than 300 papers were presented during the five-track sessions. One attendee, in a good news/bad news post-conference comment, said there were “so many good sessions at one time, I was sorry I couldn’t attend more.”
Vendors filled the exhibit space, occupying the equivalent of 157 booth spaces. Exhibitors already are lining up for next year’s conference, ION GPS 2000, to be held at the Salt Palace Convention Center, Salt Lake City, September 19-22.
Best Paper Awards for ION GPS ’99
SESSION A1: GEODESY, ENGINEERING & DEFORMATION MONITORING
Deformation Monitoring Scheme Using Static GPS and Continuously Operating Reference Stations (CORS) in California: M.A. Duffy, C. Whitaker, Metropolitan Water District
SESSION B1: INTERFERENCE & FREQUENCY COORDINATION
A Comparison of CW and Swept CW Effects on a C/A Code GPS Receiver: K.D. Johnston, AFIT
SESSION C1: WIDE AREA AUGMENTATION SYSTEMS
The Sensitivity of Category I Precision Approach Availability to GPS Satellite Constellation: P. Tran, J.-S. Wu, J. Lewellen, Raytheon Systems Company; J. Angus, Claremont Graduate University
SESSION D1: RECEIVER SYSTEMS & TECHNOLOGY
Optimum Semi-Codeless Carrier Phase Tracking of L2: K.T. Woo, NavCom Technology, Inc.
SESSION E1: SPACE SYSTEMS & APLLICATIONS 1
First Autonomous Rendezvous Using Relative GPS Navigation by ETS-VII: I. Kawano, M. Mokuno, T. Kasai, National Space Development Agency of Japan
SESSION A2: LAND SYSTEMS & PUBLIC SAFETY
New Differential and RTK Corrections Service for Mobile Users, Based on the Internet: H. Hada, Nara Institute of Science and Technology; K. Uehara, J. Murai, Keio University; I. Petrovski, S. Kawaguchi, H. Torimoto, DX Antenna
SESSION B2: SPECTRUM/WRC PREPARATION
Bandwidth Requirements for an Additional Radionavigation Satellite Service Allocation: K. Sandhoo, C. Hegarty, The MITRE Corporation; A.J. Van Dierendonck, A.J. Systems; R. Reaser, DOD; S. Frodge, DOT; D. Milbert, NOAA/NGS; M. Biggs, B. Mahoney, FAA, E. Drocella, NTIA
SESSION C2: LOCAL AREA AUGMENTATION SYSTEMS
GPS Ephemeris Verification for Local Area Augmentation System (LAAS) Ground Stations: S. Matsumoto, S. Pullen, M. Rotkowitz, Stanford University, B. Pervan, Illinois Institute of Technology
SESSION E2: SPACE SYSTEMS & APPLICATIONS II
Preliminary Orbital Results from the SGR Space GPS Receiver: M.J. Unwin, M.K. Oldfield, S. Purlvigralping, Y. Hashida, P. Palmer, I. Kitching, Surrey Space Center, Signal Computing Ltd
SESSION A3: ENGINEERING, CONSTRUCTION & MINING
Optimization of GPS on Track-Dozers at a Large Mining Operation: J.A. Flinn, S.M. Shields, Phelps Dodge Morenci, Inc.
SESSION C3: TIMING SYNCHRONIZATION & INFRASTRUCTURE
GPS Timing in Electric Power Systems: K.E. Martin, Bonneville Power Administration
SESSION D3: MILITARY APPLICATION & ANTI-JAM TECHNOLOGIES
Small Affordable Anti-Jam GPS Antenna (SAAGA) Development: K. Falcone, G. Dimos, C. Yang, Mayflower Commu-nications Company, Inc.; F. Nima, S. Wolf, Sensor Systems, Inc.; D. Yam, J. Weinfeldt, P. Olson, U.S. Army CECOM
SESSION E3: ALGORITHMS & METHODS
A Performance Analysis of an Integrated GPS/Inertial System Using Tightly Coupled Integration Methods: Y.C. Lee, D.G. O’Laugh-lin, The MITRE Corporation
SESSION A4: MARINE NAVIGATION & POSITIONING
Testing of a Multi-Reference GPS Station Network for Precise 3D Positioning in the St. Lawrence Seaway: L.P. Fortes, G. Lachapelle, M.E. Cannon, The University of Calgary, Canada; G. Marceau, S. Ryan, S. Wee, Canadian Coast Guard; J. Raquet, U.S. Air Force Institute of Technology
SESSION B4: GNSS, GPS & GLONASS POLICY ISSUES
A Modernization Deployment Strategy to Meet Military and Civil Needs: C.W. Kelley, D. Martoccia, Boeing
SESSION C4: ATMOSPHERIC EFFECTS
The Performance of Virtual Reference Stations in Active Geodetic GPS-Networks Under Solar Maximum Conditions: L. Wanninger, Geodetic Institute, Dresden University of Technology
SESSION D4: PSEUDOLITES
Integration and Testing of a Wide Band Airport Pseudolite Prototype: J. Warburton, M. Dickinson, FAA William J. Hughes Technical Center; D.W. English, J. Liu, ARINC SITE Laboratory
SESSION E4: CARRIER-PHASE POSITIONING & AMBIGUITY RESOLUTION
Resolving Carrier-Phase Ambiguities On-The- Fly, At More Than 100 km From Nearest Reference Site, With Help From Ionospheric Tomography: O.L. Colombo, USRA/NASA GSFC; M. Hernandez-Pajares, J.M. Juan, J. Sanz, Universitat Politecnica de Catalunya; J. Talaya, Institut Cartografic de Catalunya
SESSION A5: GIS & MAPPING
GRINGO: A RINEX Logger for Hand-Held GPS Receivers: C.J. Hill, M. Dumville, T. Moore, The University of Nottingham
SESSION B5: GPS MODERNIZATION
Civil GPS/WAAS Signal Design and Interference Environment at 1176.45 MHz: Results of RTCA SC159 WG 1Activities: A.J. Van Dierendonck, AJ Systems; C. Hegarty, The MITRE Corporation
SESSION C5: AVIATION APPLICATIONS
Inflight Detection of Errors for Enhanced Aircraft Flight Safety Using Digital Terrain Elevation Data with an Inertial Navigation System, Global Positioning System and Radar Altimeter: R. Gray, F. van Graas, Ohio University
SESSION D5: GPS REFERENCE & INFORMATION FUSION
3-D Perspective Displays for Guidance and Traffic Awareness: C. Jennings, K. Alter, A. Barrows, P. Enge, J.D. Powell, Stanford University
SESSION E5: ATTITUDE DETERMINATION
GPS Attitude Determination by Adaptive Kalman Filtering: R. Campana, L. Marradi, LABEN S.p.A.; S. Bonfanti, Dip. di Ingegneria Aerospaziale
SESSION A6: AGRICULTURE
RTK-Based Vehicle Tracking and Unmanned Operation for Agriculture: M. Farwell, G. Lachiewicz, D. Caldwell, ITT Industries, Inc.; M. Abousalem, Magellan Corporation
SESSION B6: GNSS ARCHITECTURE- AVIATION & SATELLITE NAVIGATION
Improved GPS Satellite Constellation Availability Model: R.A. Slattery, K. Kovach, ARINC
SESSION C6: AVL & ASSET MANAGEMENT
The GPS Fleet Management and Information System for Bus Companies: M.A. Molina, GMV Sistemas S.A.
SESSION D6: MILITARY & COMMERCIAL APPLICATIONS FUSION
GPS Signal Offset Detection and Noise Strength Estimation in a Parallel Kalman Filter Algorithm: B.J. Vanek, USAF; P.S. Maybeck, AFIT; J.F. Raquet, USAF/AFIT
SESSION E6: SPACE, CONTROL & NETWORK REFERENCE
Atomic Clocks for Space Applications: F. Emma, European Space Technology Centre; G. Busca, Observatoire de Neuchatel; P. Rochat, Temex Neuchatel Time
Exit to Applause
The ION GPS/GLONASS Interoperability Working Group (IWG), chaired by Pratap Misra, disbanded following a two-day workshop held prior to the ION GPS ‘99 conference in Nashville in September.
An international roster of speakers participated in the workshop, held Sept. 13 and 14, where data gathered as part of the International GLONASS Experiment (IGEX-98) were reviewed and analyzed. During more than six months, data on the GLONASS system were collected in a cooperative effort involving 68 stations in 25 countries (see Fall ‘98 ION Newsletter, p. 5).
Dr. Misra reported to the Executive Committee of the Satellite Division that the group had achieved its objectives. He left with the plaudits of the Committee, and the sincere appreciation of the ION.
GPS Around the Globe
Another Block IIR Launched
The launch of the second Block IIR GPS satellite, postponed in September because of Hurricane Floyd, went off smoothly from Cape Canaveral Oct. 7. Flung into orbit on a Delta II, the satellite was undergoing in-orbit checkout tests of the navigation payload in November, prior to being placed on opera- tional status. It was slotted into plane D of the GPS constellation.
The 2370- pound satellite, built by Lockheed Martin, has a 10-year design lifetime. The Air Force has contracted for 17 more Block IIRs; the R stands for Replenishment satellite. Boeing has a contract to build the Follow-on Block IIFs.
The IIRs have improved performance, inter-satellite links to maintain autonomous operation longer without ground control corrections, and longer life. The next Block IIR launch is tentatively scheduled for April 2000.
Meanwhile, Col. Douglas L. Loverro has taken over as system program director, Navstar GPS Joint Program Office (JPO) to head the $19 billion GPS program that maintains the largest satellite constellation in the Department of Defense. Loverro, a 1976 Graduate of the Air Force Academy (BS, chemistry), replaces Brig Gen. (S) James Armor who was reassigned as vice commander of the Warner Robbins Air Logistics Center in Georgia. Loverro also holds an MS in physics from the University of New Mexico. The JPO, part of the Space and Missile Systems Center, is located at Los Angeles Air Force Base.
Japan Launch Fails
Japan’s $97-million Multi-functional Transport Satellite (MTSAT), which carried a GPS-compatible navigation package, was destroyed in a launch failure on Nov. 15. The MTSAT was to support a future air navigation system, similar to the WAAS system being developed by the U.S. Federal Aviation Agency, and Europe’s EGNOS system.
An H-2 rocket, Japan’s largest launcher at 263 metric tons, veered off course when the liquid-fueled first stage engine shut down prematurely. Range officers destroyed the vehicle 7.7 minutes into the mission. It was the second consecutive failure of an H-2; the previous failure came when a $375 million data relay satellite payload was thrown into a useless orbit during a faulty launch in February last year.
The MTSAT loss deals a setback to global WAAS-like coverage for the aviation industry. U.S. Space Systems/Loral built the bird under a contract for one spacecraft.
GPS in the Handset
The deployment of GPS as a location technology for mobile phone users has long been under study and development. Now, the technology is moving to the two-way paging market.
Loc8.net of Seattle and Glenayre of Charlotte, NC, have partnered to develop new two-way paging devices that use embedded GPS chips to offer positioning services to consumers and commercial users, according to GPS World Newsletter. The devices will use Snap-Track Inc. GPS technology for wireless callers. Glenayre is also develop- ing a locator device to track parcels, vehicles or other belongings.
Service Mandatory in Phones
In the mobile phone market, an FCC mandate that requires companies to provide location services for E-911, or Enhanced emergency calling, by October 2001 is driving the market scramble to develop location technology for the steadily growing number of mobile handset users. The FCC rule is aimed at permitting central 911 operators and dispatchers to locate cellular callers within 125 meters in emergencies.
Motorola, SiRF Technology, Snap-Track, Zoltar and others are developing systems using GPS in the handsets. Competing systems utilize network-based techniques, using equipment at base stations to achieve location solutions based on the communications signals from the handsets.
Huge Consumer Market
Cellular phone service continues to be a booming business, a potentially huge consumer market for GPS equipment vendors. The number of wireless subscribers has soared, from 2.5 million 10 years ago, to 76.3 million now, according the Cellular Telecommunications Industry Association. Meanwhile, GPS already has been integrated with an increasing number of cellular phones in vehicles. Hertz, the world’s largest car rental company with 550,000 vehicles in 140 countries, for example, has more than 20,000 GPS-based car navigation systems installed in vehicles in the United States. It plans to expand its fleet in the U.S., Canada, France, Germany, the United Kingdom and elsewhere in the coming year.
A recent study by the Strategis Group of Washington, DC, found that revenues to mobile phone companies for location- based services will leap from $30 million this year to $3.9 billion by 2004, GPS World Newsletter reported. Much of this is due to the FCC mandate. GPS technology is expected to have a share of that market, particularly in rural areas, but so far there has been no single solution favoring GPS-based or network-based techniques. Some service providers are considering a combination of the two as the optimum solution.
GMount Everest Rises to New Heights
Mountaineers scaled Mt. Everest last May to measure the world’s highest mountain with GPS equipment and found it had grown seven feet since the last official survey in 1954. Further, scientists concluded that Everest appears to be moving slightly but steadily north- eastward, about 3 to 6 millimeters a year, as India continues to be shoved under Nepal and China along the great fault system that created the Himalayas.
The revised elevation of 29,035 feet (8,850 meters) was announced by Bradford Washburn, renowned moun- taineer and explorer at a meeting of the American Alpine Club held at the National Geographic Society (NGS) headquarters in Washington on Nov. 11. Mountaineers Pete Athans and Bill Crouse reached the summit in Nepal on May 5 with five Sherpas, according to an account by the NGS. “We climbed through the night so that we could be on top in the warmest part of the day,” Athans is quoted. “It was pleasant on top of the world that morning, just a little wind and 12 degrees F below. The equipment worked without a problem.”
The expedition was financed by Boston’s Museum of Science, Trimble Navigation, NGS and others. Observations were made from the summit for 50 minutes. The measurements were made in conjunction with other GPS receivers running simultaneously on Everest’s South Col, the highest permanent, bedrock survey station in the world established at 26,000 foot elevation; lightweight Trimble GPS receivers running on lithium batteries that operate in temperatures 40 degrees F below freezing are part of the survey station, the NGS reported.
Athans is the only Westerner who has reached Everest’s summit six times. More than 180 persons have been killed in attempts to scale the world’s most formidable land height. Two Sherpas carried the GPS equipment to the peak. Washburn said the U.S. National Imagery and Mapping Agency and China’s National Bureau of Surveying and Mapping accepted the new elevation.
News in Brief
GPS receivers are now being sold in Staples. Magellan and Staples have teamed to offer Magellan’s Blazer 12 receiver, GPS 315 and MAP 410 receivers, and DataSend and MapSend CD software. The new product line “complements other wireless products used on the road, such as cellular/PCS phones and pagers,” explains Doreen Romano, Sr. vice president and manager of Staples general merchandise, furniture and technology.
The Australian Marine Safety Authority has installed 12 DGPS beacon systems around coastal areas to provide improved navigation accuracies of 10 meters or less for shipping, as well as for some land users. The stations use Leica 12-channel MX 9400 receivers. Similar publicly broadcast GPS-enhanced services are now available in most European coastal countries, in China, India, South Africa, the UK, United States, Canada, and other countries.
Multi-Mode Receiver. Production models of integrated units that enable precision landing flexibility for aircraft are gaining greater market share. Rockwell Collins says 1,100 aircraft are now equipped with its MRR, and 7600 more are on order by 76 air carriers. The MRR provides instrument landing system (ILS), optional microwave landing system (MLR) used in parts of Europe, and enhanced GPS-based positioning, navigation and landing functions — all in one combined unit. The system has been certified for Boeing and Airbus Industrie aircraft, and a version for use in U.S. military aircraft.
Air Force specialists who control the GPS system at Schriever AFB, CO, disagree with a Defense Department Inspector General report cautioning about Y2K readiness. First, they’ll be Y2K compliant by Dec. 1, they say; (2), they have fall-back software patches being added to the control center just in case; and (3), they can always use calculators and sharp pencils that work fine.
Inmarsat has named Richard Storey as president and CEO, replacing the current CEO, Warren Grace. Storey, who holds a Masters in Business from the University of Chicago, will held guide the global mobile satellite consortium toward private ownership and the issuance of its first stock offering to the public, the latter scheduled for the second quarter of 2001.
Exploding Market. Companies are developing hardened GPS receivers that fit in rockets and artillery shells for precision weapons delivery. Rockwell Collins recently completed trials with the UK military of a direct-Y-code receiver on an artillery shell that can acquire and track GPS signals in six seconds while withstanding 15,000 g forces and spin rate of more than 260 Hz. Similarly, Interstate Electronics Corp. is developing a GPS receiver to fit in the nose of U.S. Navy and Army rocket-assisted 5-inch projectiles; it is coupled with inertial units for added anti-jam capability.
The European section of the Civil GPS Service Interface Committee (CGSIC) meets in the Conference Hall of the Praha Hotel in Prague, Czech Republic, Dec. 2-3.
Harold S. Burns, inventor of radio navigation systems and founder of Electro-Marine Corp. in Falmouth, MA, died at age 81 at a nursing home in Sandwich, MA on Sept. 8. Burns helped develop radio-nav systems for aircraft during WWII that evolved into the Loran system. He held nine patents and was a recognized authority on magnetic compasses and applied electromagnetism.
Inmarsat is issuing RFPs in December for three new 4th generation spacecraft, at an estimated cost of $1.4 billion, to be launched in 2004. Each spacecraft will have 200 spot beams, each beam capable of providing 432 kbps (kilo-bits per second) service, and 19 wide-area beams. Inmarsat, the global mobile satellite operator based in London, was privatized in April, and plans to issue an initial stock offering in 2001.
From the ION Historian
One of a Series of Columns By ION Historian Marvin May
An Inertial Navigation Test Facility
During the late 1950’s, some of the coldest years of the Cold War, that engineers at the Navy’s Aeronautical Instruments Laboratory (AIL) recognized that development and testing of higher performance inertial navigation sensors and systems would require a unique, dedicated test facility. Navy aircraft systems, in particular, required rapid turn on, and were subject to high vibrational levels with harsh temperature and humidity variations. Subsequent to a nationwide site survey that focussed on seismologically quiet criteria and proximity to bedrock, the Navy’s Bureau of Weapons approved a $1,150,000 contract which was let in 1961 to construct a new physical facility meeting the exacting environmental requirements of inertial development. By late 1963, AIL’s new Inertial Facility, located in Johnsville, Pennsylvania, was near completion. The main building (see figure) is a geodetic, domed circular building approximately 155 feet in diameter. Amongst the unique characteristics of the building are: a) an outer wall and center hub with vibration isolation material between the upper and lower footings to attenuate building generated vibrational disturbances, b) a concrete floor constructed of individual slabs of concrete with 3 / 4 inch expansion joints between slabs to reduce the vibration transmitted from one part of the facility to another, and c) the housing of all basic utilities within a separate, isolated Mechanical Building. The focal point of the facility, is the Inertial Sensors Laboratory, which is located below ground level to enable the test piers, stable bases upon which inertial sensors are mounted, to be bonded to the bedrock. There are 12 granite test piers, each of which is directly bonded to bedrock with a polysulfide epoxy compound. The configuration of the piers is short and squat. This shape was chosen to minimize the horizontal vibration caused by the inverted pendu-lum effect that can occur with tall narrow piers. The laboratory floor is isolated from the test piers to further reduce noise disturbances to the equipment under investigation. Independent measurements verified that the cultural noise levels on the piers as well as the long term angular stability of the piers were well below the most restrictive inertial sensor error budget specification.
From 1964 to 1996, the Inertial Facility was used to test many of the Navy’s developing inertial sensors as well as aircraft and ship inertial navigation systems. Amongst the gyroscopes tested were early ring laser and electrostatically suspended gyroscopes which were being developed to replace the existing generation of mechanical gas bearing gyroscopes. Among the first major programs undertaken was the Carrier Aircraft Inertial Navigation System (CAINS) which originally used gas bearing gyroscopes. After a series of reorganizations transferring control of the Inertial Facility from the AIL, to the Naval Air Development Center and then to the Naval Command and Control Ocean Surveillance Center, the latter was closed in September 1996 as a result of a Base Realignment and Closure Action. No government reorganization or realignment, however, could affect the stability of the building. The facility is currently being leased by the Navigation Research and Development Center of the Applied Research Laboratory of Pennsylvania State University and was transferred from the Navy via the Department of Education through a Public Benefit Education Conveyance at a commemorative ceremony on November 10, 1999. Presently, the facility is being used to test advanced fiber optic and microelectromechanical gyroscopes which may replace the existing generation of ring laser and electrostatically suspended gyroscopes.
ROCKY MOUNTAIN SECTION. The Section held its bi-annual din- ner at the Air Force Academy Club on Nov. 12. The featured speaker was State Senator Douglas L. Lamborn.
DAYTON SECTION. Michael Berarducci has replaced Danny W. Keen as chair of the Section, and also replaced John Galloway on the Bylaws Committee.
SAN DIEGO SECTION. Walter Schoppe has volunteered to serve as chair of the Section.
SOUTHERN CALIFORNIA SECTION. Clyde E. Edgar has volunteered to serve as chair of the newly formed Section in Los Angeles.
National Geodetic Survey
The National Geodetic Survey (NGS) develops and maintains the National Spatial Reference System (NSRS) using advanced geodetic, photogrammetric, and remote sensing techniques. NSRS is a consistent national coordinate system that defines latitude, longitude, height, scale, gravity, and orientation, and how these values change with time, across the United States. This information is essential to support public safety, coastal stewardship, economic prosperity, and environmental well-being. It ensures the reliability of transportation, navigation, communication, defense systems, boundary and property surveys, land recorrd systems, mapping and charting, public utilities, coastal zone management, natural resource map-ping, and a multitude of scientific and engineering applications. NGS also conducts the coastal mapping program, which includes surveying the U.S. coastline and providing precise positions of the shoreline and other features.
NGS is responsible for the photogrammetric mapping of all U.S. coastal regions, including the Great Lakes and U.S. territories. NGS provides information needed for safe air transportation, including information used to develop instrument approach and departure procedures and to investigate aircraft accidents.
NGS also provides federal leadership in developing specifications and standards for conducting geodetic surveys, coordinates the development and application of new surveying instrumentation and procedures, and assists state, county, and municipal agencies through a variety of cooperative programs.
7-12: 2000 RTCM Annual Assembly Meeting; Paradise Point Hotel San Diego, CA Contact: W. T. Adams, RTCM Tel: 703-684-4481 Fax: 703-836-4229
29-31: 7th Saint Petersburg International Conference on Integrated Navigation Systems; St. Petersburg, Russia Contact: Dr. George Schmidt, Draper Laboratory E-mail: firstname.lastname@example.org or Prof. V. Peshekhonov, Russian Academy of Navigation and Motion Control, E-mail: email@example.com
Close Window / Return to ION Website