Quotes Of The Quarter
"I guarantee you that the U.S. DoD did not foresee that its GPS would be hijacked by the civilian economy. But it happened, and the world's politicians and diplomats need to solve this problem now There are two issues to be addressed: GNSS vulnerability and sovereignty." Langhorne Bond, aviation consultant and former head of the FAA.
"An urgent decision is needed: the U.S. is committed
to developing GPS and reinforcing its global dominance. Unless Europe gives
a firm political commitment now to developing a European system, to be in
place at the same time as the next generation of GPS, it will simply be
too late." European Commission paper on proposed Galileo global satnav
1999 Nominations for Officers of The Institute
The following nominations were submitted by the 1999 Nominating Committee for officers of The Institute of Navigation. The ION's National Nominations Committee was chaired by Capt. Ben Peterson and included two representatives from each region. The nominations are as follows:
Per Enge, Stanford University
Executive Vice President:
Duncan Cox, DBC Communications
Karen Van Dyke, DOT/Volpe Center
Larry Hothem, US Geological Survey
Eastern Vice President:
Stephen Malys, NIMA
Jay Spalding, USCG R&D Center
Central Vice President:
Michael Braasch, Ohio University
Boyd Holsapple, USAF AFRL/SNAR
Western Vice President:
John Lavrakas, Overlook Systems Tech.
Len Jacobson, Global Systems & Marketing
Eastern Council Member-At-Large:
Capt. Jim Doherty, USCG-Navcen
Marvin May, ARL-Penn State Nav. R&D Center
Central Council Member-At-Large:
John Raquet, Air Force Institute of Technology
Trent Skidmore, Ohio University
Western Council Member-At-Large:
Dan Crouch, USAF/Holloman
Mohamed Abousalem, Magellan Corporation
Capt. Stew DeVilbiss
Capt. Christopher Shank, USAF National Recon. Office
Chris Bartone, Ohio University
Tim Murphy, Boeing
Sally Frodge, DOT/OST
Richard Barker, John E. Chance & Associates
Cdr. Len Allen, USCG-Navcen
Frank Mullen, Draper Labs
Pursuant to Article V of The Institute of Navigation's Bylaws, "additional nominations may by made by petition, signed by at least 25 members entitled to vote for the office for which the candidate is nominated". All additional nominees must fulfill nomination requirements as indicated in the ION Bylaws and the nomination must be received at The Institute of Navigation National Office by April 23, 1999.
Ballots will be mailed by April 30. Election results will
be announced during the 55th Annual Meeting being held June 28-30, 1999,
in Cambridge, Massachusetts. The newly elected officers will take office
on July 1, 1999. Election results will be reported in the ION Newsletter.
GPS Policy: Past Accomplishments and Future Opportunities
By Stephen G. Moran
GPS has been fully operational and providing high-quality, dependable navigation, positioning and timing services for civil and military users throughout the world for almost six years now. In that time it has been integrated into virtually every U.S. military platform and has become essential to many U.S. and allied military operations.
Civilian use of GPS has outpaced military use far more rapidly than anyone ever expected, to the point now that over 75 percent of all GPS receivers are non-military. There are over 3 million civil GPS receivers in use worldwide today, and that number is increasing by over a quarter million every month. Sales of GPS equipment and services, which exceeded $4 billion in 1998, are expected to quadruple by 2003.
Much of this rapid growth in the market for GPS equipment and services is due to the myriad new ways in which GPS is being applied to everything from agriculture to zoology. But part of this growth is also due to the positive way the public perceives GPS as a stable source of valuable information. We like to believe that this public perception of GPS is at least partially the result of the stable government policies that are embodied in the President's March 1996 Decision Directive (PDD) on U.S. GPS Policy.
A few months after the release of the PDD, the Administration started the first in a series of foreign government consultations aimed at establishing GPS as an international standard. U.S. GPS delegations traveled to Japan in the summer, to the European Union (EU) in the fall, and to Russia in the early winter to begin discussions on GPS. Since those initial meetings, we have held ten rounds of formal consultations, resulting in a Joint Statement on GPS cooperation with the government of Japan and important progress in our understanding of EU and Russian perspectives on GPS, GLONASS, and other potential regional or global navigation satellite systems (GNSS).
In 1997, two separate Presidential Commissions made a number of important recommendations related to GPS. The White House Commission on Aviation Safety and Security, which was chaired by Vice President Gore, looked at ways to improve aviation safety and security, as well as the technological changes coming to air traffic control, and what should be done to take best advantage of them. The President's Commission on Critical Infrastructure Protection looked at the infrastructures that constitute the life support systems of our nation, determined their vulnerabilities, and proposed a strategy for protecting them into the future.
Included among the more than 60 recommendations contained in the Gore Commission's February 1997 Final Report were four recommendations directly related to GPS. The Commission called for stronger strategic leadership for civil users of GPS, additional civil GPS precision ranging signals in space, a second civil signal in the next generation of GPS satellites, and protection of GPS signals from intentional and unintentional interference.
Significant progress has been made in implementing the Gore Commission's GPS recommendations. A month after the release of the Commission's Final Report, on the first anniversary of the PDD, the Interagency GPS Executive Board met for the first time. This Board was established by the PDD to manage GPS and its U.S. government augmentations. The first item on the agenda for this meeting was a discussion of how to implement the Gore Commission's GPS recommendations. By July 1997 the Departments of Defense and Transportation (DoD and DoT) had signed a Memorandum of Agreement committing the departments to identify a frequency and transition plan for the second civil signal by March of the following year. As for the other recommendations, the FAA has included additional ranging signals in space as part of their Wide Area Augmentation System (WAAS) plans, and the Administration is taking a number of steps to reduce the risk of interference to GPS. These steps include protecting the spectrum in which GPS operates, adding additional civil signals to the system, and increasing the power of one of the new signals.
Like the Gore Commission, the President's Commission on Critical Infrastructure Protection also had a number of GPS recommendations in its October 1997 Final Report. Most of this Commission's recommendations centered around the vulnerability of GPS to interference. The Commission raised the issue of using GPS as a sole means of navigation for civil aviation and other safety-critical applications, and recommended that a risk assessment be conducted of GPS vulnerability to both intentional and unintentional interference before committing to that path.
In October 1997, the President's policy received strong Congressional support, with passage of the FY 98 National Defense Authorization Act. This bill directly reflected much of the PDD language and, perhaps more importantly, when signed by the President it established in law (P.L. 105-85) our policy of providing GPS services "for peaceful civil, commercial, and scientific uses on a continuous worldwide basis free of direct user fees." This was an important step towards putting to rest international concerns about future changes in our policy on user fees.
Closing out 1997 was another important event for GPS the 1997 World Radiocommunication Conference, or WRC 97. At WRC 97, international mobile satellite interests proposed to reallocate a portion of the frequency spectrum adjacent to the current GPS civil signal for shared use with mobile satellite services. We considered this proposal to be a threat to the continued safe operation and growth of GPS worldwide, and worked closely with other delegations to reach an agreement to postpone its consideration until the next Conference in 2000 to allow more time to study the implications of the proposal.
Following WRC 97, we asked the Department of Commerce's National Telecommunication and Information Administration to lead the U.S. government's technical preparations for WRC 2000 in this area, and the State Department to lead an outreach campaign to more fully inform foreign governments about GPS and to urge them to take this into account in developing their positions for WRC 2000. We will continue this process until the WRC 2000 conference, and anticipate that an increasing number of countries will come to share our views on the need to protect the GPS spectrum.
February 1998 marked a major milestone for European interests in satellite-based navigation, with the release of an EC report laying out its strategy for securing a full European role in the development of next generation global navigation satellite systems and access to related markets for equipment and services. The EC strategy ultimately led to the recent EC recommendation that Europe develop an independent, but fully GPS-compatible, global navigation satellite system.
The following month marked a major milestone for the future of GPS, with Vice President Gore's announcement that two new civil signals would be added to future satellites, and that, like the current GPS civil signal, the new signals would be provided free of direct user fees. This announcement signaled the beginning of a major effort to modernize GPS to meet the needs of civil users worldwide into the next millenium, and was the precursor to his announcement this year of the proposed FY 2000 GPS modernization initiative.
In September, President Clinton and Prime Minister Obuchi concluded a Joint Statement on GPS Cooperation following their summit in New York. This statement, which culminated a year and a half of U.S.-Japan consultations on GPS, reiterated the U.S. intention to continue providing civil GPS services on a continuous, worldwide basis free of direct user fees, and stated Japan's intention to work with the U.S. to promote GPS as a worldwide standard. The statement also laid out a set of basic principles for cooperation and established a framework for more detailed discussions in the future.
The U.S. took another major step towards establishing GPS as an international standard in October last year by introducing an Open System Architecture concept for GPS in consultations with the European Union. The idea for this Open System standard was developed by the GPS Joint Program Office as a way of accommodating potential future regional or global satellite-based navigation systems that conform to the GPS technical standards for timing, geodesy, and signal structure. A number of policy principles were advanced as part of the Open System standard, the key ones being open signal structures to promote competition in developing user equipment and applications; no direct user fees for basic civil and public safety services; and cooperation in ensuring that adequate frequency spectrum is available and appropriately protected internationally.
In December, the White House reached a decision on the frequency and financing approach for the third GPS civil signal. This signal will be located at 1176.45 MHz, in a band that is already allocated internationally for aeronautical radionavigation safety services. Cost and operational impacts on existing military systems operating in this band will be worked out over the coming months. This decision formed the basis for the Vice President's January announcement of the GPS modernization initiative contained in the President's FY 2000 Budget.
In January 1999, the Vice President announced a major new initiative to modernize GPS as part of the President's Fiscal Year 2000 Budget. We believe this initiative will meet the growing needs of both civil and military GPS users well into the next millenium. The initiative requires an investment of over $400 million over the next six years between the Departments of Defense and Transportation (this is over and above the annual GPS procurement, operations and maintenance costs). What we will get for that investment are two new signals for civil users; a new military signal structure; and upgrades to the ground control system to accommodate the new signals.
January also saw the release of the FAA co-sponsored independent risk assessment of the use of GPS for civil aviation, conducted by the Johns Hopkins Applied Physics Lab, and co-sponsored by the FAA, the Air Transport Assn. and the Aircraft Owners and Pilots Assn. The results of that assessment confirm that GNSS can be safely used as the "sole means" of navigation, and that in the future it is capable of becoming the "sole service" navigation system which will not require a back-up system. The FAA is conducting a detailed review of the report and plans to take action with respect to each of its recommendations.
To close out January, the GPS Joint Program Office completed its certification of the GPS satellites, ground control system, and military user equipment for both Y2K and GPS End-of-Week Rollover compliance. This means that GPS users around the world can rest assured that the GPS system will not encounter problems this summer when the GPS week counters reset to zero, or this winter when the date rolls over to 2000. However, civil users are responsible for ensuring that their civil receivers will not have problems. Both the Air Force's GPS Joint Program Office and the Coast Guard's Navigation Center have included information on their websites to help in this process.
Finally, just a few weeks ago the EC issued its recommendation that Europe should proceed with development of its own global navigation satellite system, named Galileo. Recognizing the importance and growing global use of GPS, the EC has recommended that Galileo be fully GPS-compatible. To establish the revenue streams needed to finance Galileo, the EC is considering various approaches, including new GNSS receiver taxes and fee-based, value-added services. In this way, the EC plans to, in its own words, "develop and export a new global standard." Although we continue to believe that GPS and its augmentations will meet the future needs of civil users worldwide, we recognize that development of a seamless, interoperable system with a European component could potentially have additional benefits. We have a number of questions and potential concerns about the specifics of the Galileo proposal, including its proposed regulatory approach to generating revenues, and will pursue these in our ongoing consultations with the EU.
The U.S. Coast Guard has declared its Maritime Differential GPS beacon system fully operational. The Coast Guard's development of DGPS is a great success story. Starting with a great idea and a shoestring budget, they have developed a system that has been replicated in more than 31 countries worldwide. And they are now expanding the system nationwide so that civil users throughout the U.S. can look forward to navigation and position information accurate to better than 10 meters within the next few years.
The International Telecommunications Union's Working Party 8D, which has purview over a number of GPS-related spectrum issues, will hold its final meeting in April in preparation for this fall's WRC 2000 Conference Preparatory Meeting. The issues on the table for GPS include shared use of spectrum with mobile satellite services, protection of GPS signals in the space-to-space direction, and allocation of spectrum for new civil signals.
ICAO's GNSS Panel will also meet in April to approve GNSS Standards And Recommended Practices (SARPs). This is an important milestone for moving GPS forward as a basis for international air traffic management systems of the future. One question still on the table for this meeting is how SARPs for GLONASS will be treated.
Although the FAA recently announced a 14-month delay in the commissioning of WAAS, the system will actually begin broadcasting differential GPS corrections and integrity messages this summer over the continental U.S. and in oceanic airspace. Japan plans to launch its first Multifunction Transport Satellite this summer, so effectively two-thirds of the earth could begin receiving satellite-based differential GPS and integrity monitoring services from satellites by the end of the year. The third component of this seamless global satellite augmentation system is the European Global Navigation Overlay System (EGNOS). The recent announcement by the EC that all the bilateral agreements needed to implement EGNOS are now in place is a welcome affirmation of Europe's commitment to this important system.
Looking even further ahead, 2000 also promises to be an interesting year for GPS. WRC 2000 will take up the entire month of May in Geneva; WAAS Phase I will be commissioned in September; and the first annual review and determination on the continued use of GPS Selective Availability will be conducted in October.
It is our hope that this review of past, present and future GPS issues is helpful in putting recent activities in perspective. We have made a great deal of progress since the President's GPS policy was released three years ago. Because of the President's leadership on these issues, and because of the Vice President's active engagement, the U.S. is clearly at the forefront of an exciting revolution in the future use of GPS for civil, commercial and scientific users worldwide.
The author, Stephen G. Moran, is in the Executive Office
of the President, Office of Science and Technology Policy.
Text of FAA Press Release on GPS Risk Assessment
Washington, Jan. 29 - The Federal Aviation Administration (FAA) said today that an independent risk assessment of the Global Positioning System (GPS) conducted for the FAA and others found that with some improvements, augmented GPS can be "the only navigation system installed in the aircraft and the only navigation service provided by the FAA."
"We're encouraged by this finding. It tells us we're on the right course and GPS navigation is achievable," FAA Administrator Jane F. Garvey said.
The planned augmentations include the Wide Area Augmentation System (WAAS) and the Local Area Augmentation System (LAAS), both developed by the FAA, which use geostationary satellites and a network of ground stations to improve the accuracy, integrity, and availability of the GPS satellite navigation signals.
The six-month assessment was conducted by the Johns Hopkins University Applied Physics Laboratory of Laurel, Md. It was co-sponsored by the Aircraft Owners and Pilots Association, which represents general aviation aircraft owners and pilots, and the Air Transport Association, representing the scheduled major U.S. airlines.
Garvey thanked the Hopkins study team for "identifying the necessary improvements and for helping lay out a plan for implementing them." However, she cautioned that a "significant amount of cooperative effort with the aviation community, including the Department of Defense (DOD), and additional investments will be required to make the needed changes."
Garvey said the revised schedule for Phase I will provide additional time to make the recommended improvements for the later stages of GPS/WAAS. Recently, the FAA delayed the commissioning date for Phase I of WAAS by 14 months to allow more time to complete development of a critical software safety package that monitors, corrects, and verifies the performance of the WAAS system.
One of the primary purposes of the study was to assess
the risk to the augmented GPS signal from intentional interference, or jamming,
and unintentional interference, such as heightened solar activity and interference
from certain commercial TV and VHF broadcast signals. Essentially, the
study found that a combination of procedural and technical measures to mitigate
the effects of both types of interference are achievable and must be implemented
as part of the future augmented GPS system to ensure acceptable performance.
The report also identifies the need for closer cooperation with the DOD
in investigating more efficient combinations of DOD and the Department of
Transportation systems, including the possibility of additional GPS satellites.
(Johns Hopkins study results are at www.jhuapl.edu/transportation/aviation/gps/)
Text of White House Press Release on GPS Modernization
Washington, DC, Jan. 25- Vice President Gore announced today a $400 million new initiative in the President's balanced budget that will modernize the Global Positioning System (GPS) and will add two new civil signals to future GPS satellites, significantly enhancing the service provided to civil, commercial, and scientific users worldwide.
"The United States is proud to be a leader in the development of the Global Positioning System - a wonderful example of how technology is benefiting our citizens and people around the world," Vice President Gore said. "This initiative represents a major milestone in the evolution of GPS as a global information utility, and will help us realize the full benefits of this technology in the next millennium."
This initiative is only the most recent step in an ongoing public-private effort to make GPS more responsive to the needs of civilian users worldwide. National and regional GPS-based networks are now being created by governments and industry around the world to help guide everything from planes, trains, ships, and cars to tractors, snowplows, earthmovers, and mining equipment.
As announced by Vice President Gore last March, the second civil signal will be located at 1227.60 MHz along with the current military signal, and will be available for general use in non-safety-critical applications. The President's Budget supports implementing this new signal on the satellites scheduled for launch beginning in 2003.
Key to the overall modernization initiative was a recent White House decision on the frequency for a third civil signal that can meet the needs of critical safety-of-life applications such as civil aviation. The third civil signal will be located at 1176.45 MHz, within a portion of the spectrum that is allocated internationally for aeronautical radio navigation services, and will be implemented beginning with a satellite scheduled for launch in 2005. This initiative will cost $400 million over six years. The date that new services will be available to users will depend on the actual launch dates, orbiting sufficient numbers of satellites to provide useful services, and maintaining operational capabilities.
When combined with the current civil signal at 1575.42 MHz, the new signals will significantly improve the robustness and reliability of GPS for civil users, and will enable unprecedented real-time determination of highly accurate position location anywhere on Earth. This new capability will spur new applications for GPS, further expanding the rapidly growing market for GPS equipment and services worldwide.
The Inmarsat Council, composed of representatives of the 87-nation global satellite consortium, voted in February to privatize on April 15 this year. Nominations for company directors were being solicited. Upon formation, the new company plans to sell stock in an initial public offering (IPO) within two years.
The Administration's fiscal year 2000 (FY00) budget carries $17 million for the Department of Transportation's (DoT) first payment toward the modernization of GPS. It is the first time DoT has contributed to GPS funding. The FY00 amount is DoT's share that year of the $400 million that Vice President Gore said would be needed to finance two new civil signals, update ground control systems and add new military capabilities as well. Modifications to the JTIDS military system are not included in the $400 million modernization estimate.
Downed military pilots may in the future be able to transmit their GPS positions in secure voice or data messages with jam-proof and spoof-proof combat survivor evader locator radio (CSEL) equipment. A GPS receiver application module (GRAM) for jamming and a selective availability anti-spoofing module (SAASM) are being procured by the military for future CSELs.
Sensors aboard GPS satellites that detect nuclear explosions were triggered during the Leonid meteor shower in mid-November, but there were no outages in any of the 60-some military satellites in orbit operated by the Air Force 50th Operations Group. "There weren't even any minor incidents," said Col. Michael Kelly at Schriever AFB. The Air Force made no effort to reposition or reorient any of its arsenal of communications, navigation, reconnaissance and tracking satellites to avoid the comet's trailing particle showers. The next Leonid peak is Nov. 18 this year.
Pentagon contract auditors may be making a sow's ear out of a silk purse. They complained of 6-7 percent cost overruns for Joint Direct Attack Munitions (JDAM), the Air Force's program to add GPS/INS kits to weapons that, for example, can transform a dumb bomb into a weapon with 3-meter accuracy. But the AF initially expected to pay $50,000 per kit, according to Aviation Week, and Boeing subsequently said it would charge only $15,000 for a kit.
MS aloft. Mobile communications satellite systems are proliferating in space. The Iridium system, which inaugurated commercial service in November, has 66 satellites in orbit; the company already is designing second generation replacement satellites. Orbcomm, a subsidiary of Orbital Sciences, has placed 28 satellites in low orbit in service. Globalstar has contracted with Boeing for seven Delta II launch vehicles to loft 28 more satellites into orbit through the first quarter of 2000; eight Globalstar satellites already have been stationed in space (see photo).
Inmarsat explains it backed off its proposal for shared use of a portion of the GPS band for mobile satellite communications (MSS) because of "very different sharing constraints with future GNSS systems." The item, however, still is on the agenda for the next World Radio Conference (WRC) in Geneva in 2000. The U.S. FAA, therefore, is preparing a vigorous campaign for WRC2000 to block any proposals by other MSS operators to share spectrum, and to have the 1559-1610 MHz band designated for exclusive aviation navigation use.
NASA plans to shift the Space Shuttle fleet to GPS/inertial navigation to improve the vehicles' landing capabilities. Meanwhile, an integrated GPS/inertial system is being placed on the International Space Station, as well as its Crew Return Vehicle, for positioning and attitude data, and precise timing for station operations.
Langhorne Bond, former FAA Administrator, has been selected to receive the Glen A. Gilbert Memorial Award, given for lifelong achievements by an individual in the field of aviation. The award will be presented at the 44th annual convention of the Air Traffic Control Association in San Diego in September.
Russia is placing in service three new GLONASS satellites, launched aboard a single Proton rocket on December 24.
Orbital Sciences Corp., a Dulles, VA, aerospace company, has taken a leading role in the production of GPS-based automatic vehicle location (AVL) systems for mass transit bus and rail systems, and fleet management systems, with the purchase in January of Raytheon Company's AVL business unit for $21 million.
Sales of GPS products and services will soar to near $15 billion by 2003, compared with $3.9 billion at the end of last year, according to a market study by Aviso Micro Technology, Tempe, AZ. The study tracks growing integration of GPS in mobile telephones, vehicle navigation systems, and other technologies.
A new CORS station (Continuously
Operating Reference Station) operated by the New Jersey Institute of Technology
(NJIT) in Newark provides differential GPS error corrections to users through
the Internet. It is equipped with a Leica 12-channel dual-frequency SR9500
receiver. The station is part of the CORS network managed by the National
Geodetic Survey (NGS). CORS data is used for a variety of post-processing
applications. Data from the new station is available free on a NJIT website,
as well as the NGS CORS website.
Who Will Fill the Gap?
The ION Council has named the first ION Fellows, a new category of ION honorees, chosen for their contributions to advancements in the arts and science of navigation.
At a meeting during the Annual Technical Meeting in San Diego in January, the Council approved the nominations, offered by Dr. Richard Greenspan, Chairman, Nominations Committee, for the following 30 Fellows, ten regular or active Fellows, and 20 posthumous Fellows.
Regular Fellows: David Allan, John Bellamy, Grover Brown, Roger Easton, Edward McGann, Bradford Parkinson, James Spilker, Thomas Stansell, Eric Swanson and William Tull.
Posthumous Fellows: Victor Carbonara, Charles Stark Draper, Sherman Fairchild, Kenneth Fertig, Norman Hays, Samuel Herrick, Mary Janislawski, Elrey Jeppeson, Paul Jorgenson, Richard Kerschner, Edwin Link, Alton Moody, Tom Nicholson, John Pierce, William Polhemous, Wladimir Reichel, Thomas Thurlow, P.V.A. Weems, Vernon Weihe and Walter Wrigley.
At present, only 10 regular Fellows can be elected per year. There was discussion that many more deserved entry this year, and that consideration should be given to increasing the number of Fellows in future years.
In other business, the Council endorsed a report by Ken Holland to establish a Congressional Fellow Program to provide science and engineering opportunities on Capitol Hill. An ad hoc Congressional Fellow Committee was named to recommend a member of Congress whose office would sponsor the Fellow, review possible candidates for the position and suggest a budget for the program. The Committee, headed by Holland, is to report back at next year's Technical Meeting.
At a joint meeting of the Executive and Strategic Planning Committees the following day, a five-member 2000 Program Committee was named to make arrangements for the participation of the International Association of Institutes of Navigation (IAIN) with the ION in jointly sponsoring a conference to be held next year in San Diego, June 26-28. It will be the IAIN World Congress, held in conjunction with the regular ION Annual Meeting. Discussions dwelled on the role of the U.S. ION as host of the IAIN conference, and financing of the IAIN. The Program Committee will evolve into a Steering Committee to look into drafting a charter for the IAIN, and determining how the U.S. ION will support the IAIN in the future.
The following Chairs were named for upcoming meetings:
The Committees voted to hold a Y2K workshop on how the
issue effects navigation following the Annual Meeting in Cambridge, MA this
summer. It will be held in the DoT auditorium at the Volpe Transportation
Center, July 1.
GPS Modernization For The Military
By Col. James B. Armor, Jr.
Much attention has been given recently to Vice President Gore's announcement that the United States has finally decided on the placement of both a second and third civil GPS signal. However, planning for improvements of GPS for the military is also underway as a major part of the GPS Modernization program. The military effort is primarily focused on protecting the ability to use GPS should an adversary try to deny that capability. Solutions to this deficiency have been addressed by the Department of Defense (DoD) in the Navigation Warfare (Navwar) program. Started in 1996, Navwar covers near term (pre 2006) military user equipment enhancements and long term satellite changes.
The Air Force's Air Combat Command (ACC) has led the analysis of alternatives to identify the best solutions. That analysis will conclude this spring and the results are being documented as new requirements in a GPS Operational Requirements Document (ORD) jointly sponsored by ACC and Air Force Space Command (AFSPC). The new ORD should be validated through the DoD requirements process by late spring.
Acquisition and budget planning have occurred simultaneously with the analysis of alternatives and the determination of military requirements. The DoD is currently working to complete an acquisition strategy to satisfy the new requirements. The strategy is scheduled for completion in July, pending the validation of the ORD.
Though the specific results of the analysis of alternatives and the ORD are both classified and not finalized, the general intent is unclassified and unlikely to change. The intent is to satisfy the demand for near term improvements by upgrading the user equipment on high priority DoD systems. These "high priority" systems are the systems that will be affected most by an adversary's effort to deny GPS. The objectives of the upgrades are to provide direct acquisition of P(Y) code and increase anti-jam performance.
As a long-term solution, changes will also be made to the military signals to ensure continued exclusivity of the signal for the military and to provide for simple, direct acquisition of a military signal. Additionally, the signal strength will be increased as a straightforward means to counter the effects of jamming. The satellite changes are not part of the near term solution since it is impractical to change a sufficient portion of the satellite constellation before 2006.
Near term user equipment upgrades vary with the particular weapon system's mission and the performance of the its current GPS equipment. Depending on the system, either antennas or receivers, or both, will be replaced. Anti-jam and direct P(Y) code acquisition technologies for user equipment are in various stages of production readiness. Significant investment into research and development will be required to mature some of the technologies.
Key upgrades that are being planned include the proliferation of nulling antennas, development of beam-steering technologies, addition of adaptive narrowband filters, tight coupling of GPS with Inertial Navigation Systems (INS) and Doppler Navigation Systems (DNS), direct P(Y) code acquisition and widespread use of the Selective Availability, Anti-Spoofing Module (SAASM), the military's most advanced GPS security module. The upgrades to the high priority platforms will occur throughout the next decade. Other lower priority military systems will be upgraded with Navwar improvements at opportune times when the systems are scheduled for other GPS upgrades.
Plans for military signal changes are well along as a result of the joint civil/military effort to determine the general signal structure for new civil signals. Remaining signal characteristics regarding the specific modulation, acquisition code structure, data message structure and possible changes to ensure secure control of the new signal are scheduled to be defined by July. The GPS Joint Program Office (JPO) is managing the military signal design effort with engineering support from the National Security Agency, Aerospace Corporation, Mitre Corporation and several other contractors.
When the Interagency GPS Executive Board decided to host a new civil signal on L2, they located the civil signal at the center frequency to allow for a new "split spectrum" military signal at both edges of the GPS L1 and L2 spectrum allocation (see Figure 1). A split spectrum military signal enables several Navwar objectives. The new signal allows for direct acquisition of the military signal. This avoids initial acquisition of a signal through the C/A code that may not be accessible at certain times and locations due to efforts to deny civil GPS signals to adversaries. A split spectrum signal also permits new techniques to prevent use of L1 and L2 civil signals with minimal fratricidal impact to the new military signals. And finally, the new signals can operate at a higher power level without interference to the civil use of the C/A code. Therefore, to accommodate these Navwar objectives, the military is focusing its signal design efforts on building a new signal, referred to as the "M-code", that is spectrally separate from the civil signals.
The on-going signal design effort is assessing a number of alternative split spectrum modulations, as well as acquisition and data message concepts. It is also considering new security control mechanisms for the M-code. A decision process is being developed to select the signal alternative that provides the greatest capability to the military. Data from analysis, simulation and brassboard testing will be used to select the best signal. Most of the details of the M-code signal structure are classified and can't be addressed in this article.
The GPS JPO expects several years of M-code development and test will be required to finalize the signal content and determine the signal performance. Minor changes to the signal may occur as a result of the rigorous testing. A signal specification will not be released to user equipment manufacturers until after this signal testing, probably in the 2004 timeframe.
This initial signal testing is currently planned to be limited to ground testing. However, if the ground testing doesn't provide enough confidence in the signal performance, space based testing will be conducted before the M-code signal specification is released. The objective is to release the new signal specification as soon as the DoD can guarantee the signal performance. Early specification release will allow early production of M-code capable receivers and a quicker transition to the new M-code.
An obvious means to counter jamming of military receivers is to increase the strength of the GPS military signal. Therefore, the JPO is considering several means to raise the signal strength. Increasing the power of the Earth coverage signal is possible, but due to limitations in producing and managing power on a satellite, this method provides only a minimal increase. However, a high gain antenna can produce significantly greater signal strength in a smaller area of conflict, so several high gain antenna concepts were considered as part of a study with the GPS Block IIF contractor. The specific means of increasing military signal power will be determined this summer as part of the overall acquisition strategy. We anticipate that satellite technologies will evolve so the signal strength could be increased even more in the future.
Many military users are concerned with the effects of signal changes on their current equipment. In response, AFSPC and ACC have identified backward compatibility as a high priority so the current investment in both civil and military GPS receivers will be protected. The current C/A and P(Y) signals will continue to be transmitted for the indefinite future. In fact, increasing the power of the P(Y) code signal is being considered.
The first satellite that will transmit the new M-code is expected to be launched in 2005. Our initial plan is that this will be the seventh GPS Block IIF satellite. The third civil signal, L5 at 1176 MHz, is expected to be available on satellites starting with launches in 2003. None of the acquisition strategies being considered for GPS Modernization will delay or accelerate the current GPS satellite replenishment schedule.
Of course, new receivers will be required to process the new military signals. The DoD realizes that many changes to GPS receivers are likely in the next decade for Navwar upgrades, a new military signal, possible avionics upgrades for aircraft, to replace aging receivers and other still unknown changes.
To allow for efficient, cost effective upgrades to military receivers, the GPS JPO is sponsoring the development of the GPS Receiver Applications Module (GRAM). The GRAM establishes a common, card based GPS receiver standard. A GRAM standard currently exists for an avionics form factor and the GPS JPO has contracts with several developers to create a similar standard for ship, handheld, projectile and precision guided munition form factors. Therefore, M-code will be available to users in future GRAM receivers in most form factors. Users that already have GRAM receivers will be able to easily upgrade their receivers with an M-code capable GRAM card.
In summary, plans for modernizing GPS for the military are progressing. Specific requirements and funding and acquisition strategies to satisfy those requirements will be finalized by the end of this summer. Both user equipment and satellite changes will likely be required to meet the military's primary objective: protecting the ability to use GPS should an adversary try to deny that capability.
Col. Armor of the Air Force is System Program Director,
Navstar Global Positioning System
FRP98 Nears Release
By James V. Carroll
After a long process influenced by significant policy developments, the 1998 Federal Radionavigation Plan (FRP) is nearly ready for departmental approval and publication. The FRP is the definitive source for U.S. government policy on the use of radionavigation systems operated by the federal government. The systems include GPS and its augmentations, radiobeacons, ILS, VOR/DME, Loran-C, and TACAN. Published every two years by the U. S. Transportation and Defense departments, the next revision to the FRP is scheduled to be ready in spring 1999.
Radionavigation users now targeted by the FRP include not only air and marine navigators, but also land vehicle navigation users and those involved in such activities as surveying, weather research, time synchronization, mapping, and many other civil activities that exploit radionavigation systems. Recent FRPs reflect the greatly expanding use of GPS and its various augmentations. Important augmentations include the FAA's Wide Area Augmentation System (WAAS) and Local Area Augmentation System (LAAS), and the U.S. Coast Guard's Differential GPS (DGPS) radiobeacons.
In arriving at this point, the FRP needed to reflect developments that affected key federally operated radionavigation systems. These include decisions to: delay the installation of the first phase of WAAS, identify two new civil GPS frequencies, delay "phase-down" of many ground-based approach navigation systems, and maintain and operate Loran-C until at least the year 2008. These developments are reflected in the approval copy of the new FRP.
The initial operating capability of WAAS now will begin in the year 2000. The delay of about a year is attributed in part to difficulties with some of the software. The WAAS full operating capability consequently has slipped to the year 2005, with a further qualification tying this date to "achieved system performance." Nevertheless, early WAAS flight tests have been encouraging. LAAS milestones remain largely intact.
WAAS was designed to support operations down to and including Category I approaches. LAAS, a local-area GPS augmentation, was designed primarily to support Category II and III precision approaches, although it also is designed to supplement WAAS on Category I approaches. In order for these systems to achieve operational status as sole means systems, the FAA must demonstrate their ability to satisfy navigation performance requirements (accuracy, continuity of service, availability, and integrity).
Study Affects RFP
A GPS risk assessment conducted by Johns Hopkins University's Applied Physics Lab reached the main conclusion that GPS augmented by WAAS and LAAS can support the FAA's navigation performance requirements in the National Air System as the only navigation system installed in the aircraft and the only navigation service provided by the FAA. In a bit of a retraction from earlier expectations, the study declares that unaugmented GPS is capable of meeting navigation requirements only for oceanic flight, if the constellation is increased to 30 satellites. However, the study does state that appropriate configurations of GPS and WAAS will support Category I precision instrument approaches, and that enhanced GPS/LAAS configurations can support Category II and III operations.
Since some of the study's recommendations were based on fully implemented civil frequencies, it appears that the present ground-based approach navigation aids will enjoy a longer life than previously planned. The 1998 FRP calls for the initiation of phase-down of ground-based aids (excepting TACAN, the military counterpart of VOR/DME) to occur in the year 2005. This date is tied to WAAS performance. The date for initiating TACAN phase-down had not been finalized at the time of this article, but it is expected to be designated in the 1998 FRP.
Another event impacting the FRP is the announcement by Vice President Gore, in March 1998, that a second non-safety-critical CA-coded civil signal is to be provided at the GPS L2 frequency (1227.60 MHz). In January 1999, the Vice President also announced the selection of a third civil signal at 1176.45 MHz, part of the spectrum allocated for aeronautical radio navigation services. The third civil signal can meet critical safety-of-life applications required by civil aviation. GPS satellites scheduled for launch beginning in 2003 will be able to broadcast the second civil signal, and the third signal can be implemented on satellites scheduled for launch beginning in 2005. The full GPS constellation is not expected to be updated with the new civil capability until at least 2010.
While the conclusions of the Johns Hopkins study appear to relieve the FAA from the burden of requiring the implementation of supplemental navigation systems, many in the national and international navigation community continue to argue strongly for such backups. FAA Administrator Jane Garvey has stated her belief recently that GPS will be a primary means of navigation, rather than a sole means. Backup systems could include inertial navigation systems, a barometric altimeter/GPS combination (which may be able to meet navigation requirements through nonprecision approach for GPS unaugmented by WAAS or LAAS), Loran-C, or a combination of systems.
The status and future use of Loran-C remain uncertain, although the 1998 FRP will present recent decisions to push back its minimum termination date by eight years. Booz-Allen and Hamilton performed a cost-benefit analysis of Loran's ability to serve as a supplemental system to GPS during en route and nonprecision approach flight phases. The study concluded that there are positive benefits to including either the present, refurbished, Loran or "enhanced" Loran. Enhanced Loran exploits recent advances in receiver and signal processing technology, improvements in antenna design and installation, transmitter design and operation improvements, expanded coverage, and an ability to broadcast DGPS corrections.
Congress approved funding in 1999 for capital improvements to Loran-C, and has planned further funding in fiscal year 2000 for future upgrades. Loran-C continues to be used with regularity by mariners and general aviation pilots. It also continues to provide timing services.
Status of FRP
Following two user meetings on the FRP held last winter, a series of Working Group meetings were held to update the 1996 FRP, in part by assimilating and incorporating various policy updates. The FRP Working Group was composed of about 20 representatives of the major agencies responsible for the content and production of the FRP: parent DoT, DoD, USCG, FAA, and DOT land transportation agencies and projects such as Federal Highways Administration, Federal Railroad Administration and Intelligent Transportation Systems.
At this writing, the FRP process was being reviewed by relevant federal agencies. Final review and acceptance by DoT and DoD Secretaries must be completed, followed by publication and distribution. When the FRP is approved, it will be posted immediately by the USCG Navigation Information Service,  313-5900, or http://www.navcen. uscg.mil. For free paper copies of the FRP, available several weeks later, Fax request to: J. Carroll, Volpe Center for Navigation,  494-2628.
The author is with the Volpe National Transportation
Systems Center, Cambridge, MA.
Risk Assessment Raises Risks at FAA
The Federal Aviation Administration (FAA) is assessing actions to use augmented GPS-based systems on aircraft as a primary means, but not as a sole means, of navigation in U.S. air space for about the next decade. It is keeping open options on the need to retain substantial backup ground radionavigation support for an indefinite period.
The FAA uses primary and sole means as defined by the International Civil Aviation Organization (ICAO). Broadly, primary is an on-board system that does not meet all availability and continuity requirements and is used with operational restrictions. Sole means has no restrictions. Both refer to avionics, not ground-based aids.
FAA policy on GPS was still evolving in March following two contrary events in January: an FAA setback in an announcement that it was delaying phase one implementation of the troubled Wide Area Augmentation System (WAAS) by 14 months until September 2000, and a favorable independent risk assessment that found that augmented GPS can serve as the only system for aviation navigation.
The WAAS delay, the FAA said in a statement, is "to allow more time to complete development of a critical software safety package that monitors, corrects and verifies the performance of the WAAS system." Phase one of WAAS is designed to provide enroute navigation and to enhance GPS accuracy to provide a capability for Category 1 approaches. The augmentation signals to be broadcast through two Inmarsat satellites in this initial stage will be limited in coverage to about one-half the continental United States.
The risk assessment study was performed over six months by the Applied Physics Laboratory (APL) of Johns Hopkins University in Laurel, MD, on behalf of the FAA, the Air Transport Association (ATA), representing commercial air carriers, and the Aircraft Pilots and Owners Association (AOPA), representing general aviation. The study affirmed in general that an improved and augmented GPS can "satisfy the performance requirements to be the only navigation system installed in an aircraft and the only service provided by the FAA for operations anywhere in the National Airspace System (NAS)."
But that finding was conditioned on the successful implementations of WAAS and a high grade version of the FAA's Local Area Augmentation System (LAAS), a 24-satellite GPS constellation plus four geostationary satellite augmentation signals, improvements in receivers, pseudolites at airports for LAAS services, and other improvements. At the same time, the study said that an unaugmented GPS could not provide sole means navigation except in the less stringent oceanic regions, and then only with a 30-satellite constellation.
Further, the study noted that unintentional interference could be caused by TV broadcasts on channel 23 in the vicinity of airports, by commercial VHF radios such as used for vehicle fleet dispatch, and perhaps by some military radar. The more serious threat, however, the report says, arises from intentional jamming. The report concluded that these risks were manageable, using a combination of procedural and technical measures, and other changes, to ensure that performance standards in the national airspace are met. Two other forms of potential interference - ionospheric propagation and ionospheric scintillation - were deemed predictable and manageable, particularly with introduction of a second civil frequency. The current modernization plans, however, will not provide even 18 GPS satellites with second civil frequencies until about 2010, perhaps later.
The report provided a needed boost to the WAAS and LAAS programs. WAAS in particular has been plagued by delays and criticized for cost overruns. Despite the favorable study results, the FAA reacted warily.
FAA Administrator Jane Garvey, while praising the study, cautioned that a "significant amount of cooperative effort with the aviation community, including the DoD, and additional investments will be required to make the needed changes." Federal officials subsequently at an ICAO meeting in Brazil told conference attendees there that GPS will be primary, but will not be approved for sole means navigation for some time, and will require backup.
The ATA and AOPA recommended "rapid implementation of WAAS and two additional geostationary signals; collaboration with the user community on a national GPS plan; greater civilian control in the management of the GPS system; and accelerated implementation of procedures and policies to produce early operational benefits."
The report drew some criticism that it was too narrowly focused on satisfying only U.S. civil aviation concerns, that it failed to address jamming by international terrorists, that it relied on one space-based system that could experience system-wide catastrophic failures as opposed to limited or local outages experienced by existing individual ground-based aviation radio systems. European sources renewed criticism that the risks of the U.S. military turning off GPS were not addressed; some ICAO members were frustrated over U.S. hedges about clearly declaring GPS as a sole means of aviation navigation. The FAA, meanwhile, held meetings in February in a continuing evaluation of its plans to transition to a totally space-based navigation system. (An full Web version of the study's results is available at www.jhapl. edu/transportation/aviation/gps/.
Europe Steps it up a Notch on GNSS
A European Commission (EC) report urges the establishment of an independent Global Navigation Satellite System (GNSS-2), separate from but fully compatible with GPS, to be called Galileo. Members of the European Union (EU) next are expected to make key decisions concerning the report's recommendations this summer, including methods of financing the proposed global civil system, estimated to cost $2.5 billion to $3.3 billion. After a series of meetings in which the U.S. rejected joint participation in GPS, the EC report said it was now critical that Europe launch its own worldwide civil satellite navigation system to ensure that it maintains control over systems vital to Europe's safety, that European industry be able "to compete in this lucrative market," and that Europe had clear access to technological developments.
Minimum 10-Meter Accuracy
"The recommended approach is to develop a Galileo which is global in coverage from the outset and independent from the US GPS, but fully interoperable with it," the EC report says. Russian involvement is invited, and use of the Russian GLONASS system would be a major advantage because of the valuable frequencies already allocated. But it cautions that it remains to be seen if "this can be established on a satisfactory basis."
Technical parameters are described in broad terms: a system using core constellations of either 21 MEO (medium earth orbit similar to GPS/GLONASS) satellites or 36 MEO satellites; the 21-bird system, combined with GPS, would meet European requirements for a minimum 10-meter accuracy, while the 36-bird system would meet requirements fully and independently. The signal structure would be compatible with GPS, but enhanced to improve European service.
Key to the report was the proposal for a public/private partnership, with government providing about one-half the financing to launch the system and industry the remainder. The possibility of revenues was advanced, from levies on receivers, to added charges for "restricted access service," the latter presumably differential corrections and/or additional liability coverage.
The proposal faces a lengthy approval cycle ahead. It must
be okayed by the Transport Ministers Council in April, later by the European
Space Agency ministerial council, and then considered by EU heads of state
at a summit in June. Germany is expected to take a lead role in Galileo,
up to a 30 percent stake, according to Aviation Week magazine. Industry
participation, however, depends on the level of confidence the private sector
develops in the project.
Federal DGPS System Expands
The low-budget, high-tech U.S. coastal Differential GPS (DGPS) network, and the expansion of that system inland into a nationwide DGPS system, won the plaudits of top federal officials at ceremonies held at the Coast Guard Navigation Center in Alexandria, VA, March 15.
Principle speakers included Secretary Rodney Slater of the Department of Transportation, Coast Guard Commandant James Loy, Morley Wingrad from Vice-President Gore's office, and Capt. James Doherty, Commanding Officer of the NavCen.
Maritime in Full Service
The DGPS system of more than 55 reference stations ringing the U.S. coast, Great Lakes and navigable inland waterways broadcasts GPS corrections to serve shipping. It provides maritime commerce with the data to achieve GPS accuracies of less than 10 meters, more often 1-to-3 meters, meeting requirements under most conditions for approaches and entrance to high-traffic harbor areas. The U.S. Coast Guard system set world standards; more than 30 countries have developed similar DGPS maritime networks.
Since 1966, it has functioned under initial operational capability. At the ceremonies, the Coast Guard declared full operational capability for the DGPS system. At the same time, at the flick of a switch, the first eight stations in the growing Nationwide DGPS system (NDGPS) to serve inland U.S. areas came on the air for initial operation to highlight the expansion of the free federal positioning/navigation service to a universe of new users.
Expanded National Network
At an estimated capital cost of $37 million, small by federal standards, the government plans to install some 67 new reference stations to blanket the continental U.S. and major areas of Alaska (the Anchorage-Fairbanks corridor and elsewhere) with reference stations capable of serving a variety of users, including safety-of-life applications in rail and highway transport and emergency police and medical services. A government benefit study discovered more than 20 federal agencies alone with public safety needs that can be met by NDGPS; the study found a cost/benefit ratio of 1-to-140.
The Coast Guard, which is building the system and has operational control through its Alexandria, VA, NavCen, hopes to complete work on eight to 12 stations this year. Funding has grown from $2.4 million approved by Congress under an amendment sponsored by Sen. Daschle last year, to $5.5 million for the current FY99; President Clinton has asked Congress for a total of $10.4 million in FY00.
Planners hope to complete the system the entire NDGPS by the end of 2002. Of the total system, some 57 sites will utilize former Air Force GWEN, or Ground Wave Emergency Network, stations. Officials estimate a net savings to the government of $16 million, calculating savings to the AF in decommissioning costs, and to civil agencies in converting existing structures rather than procuring new land and facilities.
The eight stations ceremoniously activated - all GWEN facilities
- are at Whitney, NE; Savannah, GA; Appleton, WA; Driver, VA; Penobscot,
ME; Hartsville, TN, and Clark, SD.
From The Editor
When she first came into the world -- on Valentine's Day, Feb. 14, 1989 -- she was not expected to live beyond 7.5 years. But 10 years later, she, nicknamed "Cupid", was healthy and robust, and had traveled around the world 7,300 times. 'She' is the maiden Block II GPS satellite, launched in 1989 on the first of the Delta II series of launch vehicles.
Eight Block II satellites, four launched in 1990, are still in service. "Cupid", or SVN14, is the oldest working GPS satellite. The Air Force 2nd Space Operations Squadron, and prime contractor Boeing, celebrated the 10th anniversary event at Schriever AFB, formerly Falcon AFB. "The GPS program has exceeded all initial expectations," Lt. Col. J. Kevin McLaughlin, Squadron Commander, said at the observance. "The extended lifespan reflects on the quality in design and manufacture of the Block II satellites."
While this is good news for downtrodden taxpayers and harried AF system operators, it underscores one of the current dilemmas of the modernization movement: when will civil and military users enjoy the benefits of added signals and other improvements? In the article in this issue, Who Will Fill The Gap?, the answer is that it may be 10+ years before the first of the next generation Block IIF is launched carrying a second civil frequency. Given the longevity experience of the Block IIs, as well as anticipation that the current Block IIRs, 20 of them, may also enjoy a long and lasting prosperity, the answer seems conservative. Only one IIR has been orbited.As the article points out, an estimated added $150 million would put a second frequency on the last 12 Block IIRs. This is about one-tenth the cost to build and launch those same 12 satellites, relatively small compared to the gain in benefits that could be realized earlier, by both civil and military users.
Keith McDonald, a former ION president and current president of the International Association of Institutes of Navigation, made a sort of back-of-the-envelope calculation of the benefits denied. In a letter to the panel of the Satellite 99 Conference in Washington, McDonald pointed to market surveys by the Commerce Department, by the GPS Industry Council and others. They generally agree that the U.S. GPS industry will grow to an $8.5 billion business by 2000, and to an estimated $30 billion business by 2005, "and similar growth is expected through the decade," McDonald noted. "The cumulative size of the GPS industry for this time period -- the decade 2000-through-2009 -- is more than $300 billion."
Figuring a very conservative federal tax bite of merely 20 percent, GPS industry employees alone would pay Uncle Sam more than $60 billion in personal taxes over the same decade. The total cost of GPS spacecraft, launch vehicles, control segment and all other costs to keep GPS healthy and operating during the same time, McDonald estimated, appear to be about $4 billion to $5 billion. "The bottom line is that GPS is paying for itself and returning 10 times that amount to the U.S. Treasury," McDonald concluded. Of course, these tax revenues flow to the general fund, not directly to DoD or DoT to pay for GPS improvements. At budget time, these departments face severe overall spending restrictions, thus, they are reluctant to earmark substantial expenditures for GPS enhancements.
Nevertheless, a case has been made. Do we hear the abacus
beans clicking now at the Office of Management and Budget?
Loran Loop Antennas Reduce Noise in Aircraft Tests
Loop antennas used with Loran-C receivers were shown to dramatically reduce the problem of electrical noise in loran navigation performance during recent controlled tests with aircraft, raising hopes of using loran as an aid to the FAA's GPS-based Wide Area Augmentation System (WAAS).
Tests under extreme p-static conditions, the corona caused by static discharges usually at the trailing edges of wings and the airframe in rainy weather, demonstrated Loran-C receivers with loop antennas suffered little degradation in loran reception or navigation performance.
Receivers with aviation-quality whip antennas, long a problem in aviation, suffered drops in signal-to-noise ratios of greater than 25 dB. The identical receivers hooked to loop or magnetic-field antennas suffered a drop of only 2 dB, insignificant to navigation accuracy.
The tests were conducted by Illgen Simulation Technologies, Goleta/Santa Barbara, CA, a firm specializing in navigation and communications testing and software development. Loran equipment was supplied by LOCUS of Madison, WI, and Megapulse of Bedford, MA. Ohio University provided the PA-32-301 aircraft.
From The ION Historian
Navigation is often defined as both an art and a science. It is difficult to fully appreciate this duality, or perhaps, ambiguity, until one peruses the strikingly elegant book by Dr. Peter Ifland entitled, "Taking the Stars, Celestial Navigation from Argonauts to Astronauts". This is a lavishly illustrated volume published in 1998 by the Mariner's Museum of Newport News, Virginia and Krieger Publishing Co. of Malabar, Florida.
Two panoramas converge in this exceptional volume. One is a parade of utilitarian but often ingenious devices for celestial navigation stemming from the ancient Arabian kamal, the cross-staff and back-staff, the astrolabe, and the marvelous variations on the divided celestial circle-the half-circle, quadrant, quintant, sextant, octant, and their relatives. The other panorama is a historical chronology of the great craftsmen and inventors of celestial navigation instruments, such as Thomas Godfrey, Captain John Davis, and John Hadley.
The book reflects the author's deep respect for the artistry and technical skills of the makers of the celestial instruments, emphasizing the almost ritualistic aspects of taking star sights. Many of the instruments illustrated in this book are from the author's personal collection that can now be seen at the Mariners' Museum, Newport News, Virginia. It has application to the scholar, the collector, and the avid student of navigation methods and lore. While its main showcase is the almost 200 colorful, close-up, never-before published photographs of instrumentation from private collections and the world's great maritime museums, it also includes voluminous historical and descriptive information on celestial techniques, and on each device.
Art & Science
Intertwined are the elements of art, as in the elaborate engravings on the octant crossarms, and the contributions of science, as in the detailed explanations of the sight geometries. The first two chapters chronicle the mainstream of device development from a historical perspective. Each of the following chapters addresses a principal feature of navigation instruments such as the optics, the scales, and the artificial horizons. Often omitted from any education curricula are the failures; however, Dr. Ifland has collected and illustrated the inadequacies of earlier designs that subsequently stimulated attempts at improvement. Later chapters address the use of similar equipment for angle measurements associated with surveying and distance finding. The last chapter shows the application of aircraft and spacecraft sight reduction techniques using instrumentation employed aboard World War I and II aircraft, as well as the Gemini IV space flight.
The volume concludes on a nostalgic and somewhat melancholy note. In the epilogue, the author notes that superior technology ultimately will prevail. He writes: " With the advent of GPS and other high-performance electronic satellite navigation systems that are fast and inexpensive, require no operator effort, and give a continuous read-out of position to within a few meters, using a sextant to take the stars is surely obsolete. Perhaps the death knell for celestial navigation was sounded in May 1998 when the United States Naval Academy announced it was discontinuing a course on celestial navigation and the use of the sextant that has been taught since the Academy's founding in 1845. Sooner or later, air and nautical almanacs will no longer be published and there will no longer be a need for hand-held instruments for taking the stars." Somewhat sadly, this may mean the demise of art in navigation.
We are looking for unneeded or excess inertial navigation equipment for historical and educational purposes. These would include accelerometers, gyros, platforms, synchros, inertial platforms, gyrocompasses, inertial measurement units, etc. With all the moving and consolidation going on in DoD, there should be some available. Private contractors may be eligible for a tax write-off. Please contact, Historian at firstname.lastname@example.org (Tel 215-682-4003; Fax 215-682-4023).
Alberta Chapter. The November 12 meeting at the University Club, University of Calgary, featured talks by a representative of Leica and a member of the government's Western Economic Diversification (WED) department. Richard Andres of Leica described Leica's System 200 and 300 component systems, and the SR399, SR9400 and SR9500 receivers. Rick Barber reviewed activities of WED that support small businesses in economic development in Western Canada. New officers elected for the year at the Jan. 14 meeting are Dr. Gerard Lachapelle, Chair; Randy Hrynyk, Vice Chair; Dave Thomson, Treasurer, and Scott McCarron, Secretary.
Dayton Section. The Section held a luncheon meeting at the Wright-Patterson AFB Officers Club Feb. 11. Dr. Michael S. Braasch, Asst. Professor, Electrical Engineering, Ohio University, as guest speaker presented a report on advanced receiver processing techniques for GPS multipath mitigation.
Houston Section. Two experts on harnessing geographic information systems for petroleum exploration spoke at this year's first quarterly meeting of the Section, a dinner at Rudi Lechner's Restaurant sponsored by Nortech Geomatics USA. Jonathan Stigant, Chevron Petroleum, gave a report entitled, The Impact of Geodesy and GPS on GIS Data Management in International Oilfield Operations. The second speaker, Todd Porter, GeoWorks Co., provided an overview of complex data sets that go into a successful GIS exploration system for improving efficiency and quality of land, TZ and OBC field seismic operations.
New England Section. The 11th evening meeting of the Section, held at the Volpe Center in Cambridge Jan. 21, featured two speakers. R. Michael Garvey, Frequency and Time Systems, a division of Datum, Inc., described the capabilities of atomic and quartz timekeeping, including the use of cesium beam as the standard for GPS because of its accuracy and long-term stability. Walter Guinon, Draper Laboratory, demonstrated the Bio-Kinematic Navigator, which provides interim navigation to persons on foot even when GPS signals are blocked by forest, buildings or interference by inputting the measured step displacement of each step; reacquisition times also are speeded up so even a brief glimpse of a signal can produce a fix.
Southern New Mexico Section. New officers for the year are Dan S. Crouch, Chair; Lt. John Brady, Vice Chair; Andy J. Chasko, Secretary, and Keneth R. Wernle, Treasurer, according to outgoing Chair, Fred Nadeau.
Rocky Mountain Section. Volunteers from the Section provided classroom instruction and hands-on demonstrations of GPS equipment in seminars held for 6th, 7th and 8th grade students at Eagleview Middle School in Colorado Springs Feb. 10. About 100 students aged 11-to-13 in the talented and gifted division came to two sessions, a first-ever event conducted by the Section in its efforts to establish itself as the premier group providing leadership and instruction in navigation in the Rocky Mountain area. Four new Garmin 12 GPS receivers acquired by the Section through the assistance of the ION National Office were used in the school demos. Special Events Director Mike McKnight organized the event. Volunteers who took off time from their jobs and joined Chair Mike Cimafonte for the back-to-school day included Daniel Knezha, Robert Cass, Ted Driver, Tom Mullikin and Pat Sharrett. The meeting site for the March 18 Section gathering was provided by United Airlines at their United Training Facility. Members were encouraged to make efforts to increase attendance at the meeting. -Information provided by Michael Cimafonte, Chair.
NEWS FLASH ALERT
MSS OUT-OF-BAND EMISSIONS LIMIT FOR GPS AND GLONASS BEING SET IS IT ADEQUATE? IF IT IS NOT, WIDESPREAD INTERMITTENT INTERFERENCE COULD RESULT. CAN YOU LIVE WITH THIS? IF NOT, COMMENT TO THE FCC NOW.
The Federal Communications Commission (FCC) has finally come out with the Notice of Proposed Rule Making (NPRM) on the out-of-band emissions from Mobile Satellite Services (MSS) in the 1610-1660.5 Megahertz (MHz) band. This limit may not be sufficient to protect all uses of GPS, since it was developed by the aviation community. It sets the wideband limit of
-70 dBW/MHz and narrowband at -80 dBW. The GPS and MSS sets must be separated by 100 feet or greater. If this limit is not strict enough, it could cause widespread, intermittent interference to GPS operations. Some tests have indicated that certain GPS receivers will be interfered with by this limit, indicating it is not stringent enough. This NPRM is now in the public comment period until May 3, 1999. Comments should be made to the FCC. If you do not comment, this standard will most likely go forward domestically and internationally. See the Dept. of Transportation's USCG Navigation Center website (www.navcen.uscg.mi/) under "RNAV SPECTRUM ISSUES" for further information on this issue.
Included with this NPRM are other critical issues, such as Enhanced 911 (E-911) services on global communications. Thus far, the FCC has resisted making E911 a requirement for all satellite providers. The NPRM title indicates that the main focus for the FCC is on Global Mobile Personal Communications (GMPCS) by Satellite. While GMPCS is important, it should not be instituted at the expense of another existing service, particularly one as important as GPS. The NPRM (FCC 99-37; IB Docket No. 99-67, RM No. 9165) can be obtained from the FCC website at: www.fcc.gov/Bureaus/ International/Notices/1999/
U.S. Naval Observatory
The U.S. Naval Observatory performs an essential scientific role for the United States, the Navy, and the Department of Defense. Its mission includes determining the positions and motions of the Earth, Sun, Moon, planets, stars and other celestial objects, providing astronomical data; determining precise time; measuring the Earth's rotation; and maintaining the Master Clock for the United States.
Observatory astronomersformulate the theories and conduct the relevant research necessary to improve these mission goals.
This astronomical and timing data, essential for accurate navigation and the support of communications on Earth and in Space, is vital to the Navy and Department of Defense. It is also used extensively by other agencies of the government and the public at large.
New Corporate Members
The ION extends a warm welcome to the following new Corporate Members:
18: Reply comment period closes. Reply comments due to the FCC on out-of-band emissions from MSS to GPS and GLONASS. (FCC 99-37; IB Docket No. 99-67, RM No. 9165)
9-14: 1999 Annual Assembly Meeting of the Radio Technical Commission for Maritime Services (RTCM); Wyndham Palace Hotel, Orlando, FL; Contact: W.T. Adams, Tel: 703-684-4481, Fax: 703-836-4229
24-26: Sixth St. Petersburg International Conference on Integrated Navigation Systems; St. Petersburg, Russia; Contact: Dr. George Schmidt, Draper Laboratory, Tel: 617-258-3841, Fax: 617-258-3355, Web Site: http://www.draper.com
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