One of the satellites in the Chinese domestic satellite navigation system, Beidou, is no longer in geostationary orbit and appears to have been abandoned.
According to information from the U.S. Space Command, the orbit of Beidou 1D was raised by around 130 kilometers on February 18, 2009. This may have been an attempt to place the satellite in a graveyard or disposal orbit. Such a maneuver is carried out by spacecraft operators when a satellite reaches the end of its life due to a malfunction or some other reason. However, the recommended boost height for geostationary satellites is about 300 kilometers, where a satellite is above the zone used to reposition active geostationary satellites and also provides a buffer for natural orbit variations due to solar radiation pressure and other causes. Beidou 1D may not have had sufficient propellant to reach desired orbit height.
In its current orbit, Beidou 1D is drifting westward at a rate of about 4.5 degrees per day and has already completed one circuit of the Earth. On July 17, it was positioned just west of the Greenwich meridian.
China launched Beidou 1D in February 2007; according to the Xinhua news agency at the time, the satellite was to serve as a backup to the three satellites already in orbit, perhaps replacing the first Beidou satellite, Beidou 1A, when necessary. Subsequent reports did indicate that Beidou 1A appeared to have malfunctioned.
It is not known what kind of malfunction Beidou 1D suffered or whether its signals have been switched off. Accurate detailed information about the current status of the Beidou domestic system is difficult to obtain.
China has plans to improve its domestic navigation system and to develop a global system known as Beidou 2 or Compass. Its first medium Earth orbit satellite, Beidou M1, was launched on April 13, 2007, followed by a geostationary satellite, Beidou G2, on April 14, 2009.
— Richard Langley
Galileo, Too, Has Accounting Problems
The European Union’s Galileo program has been ill-prepared and badly managed, according to a report by the European Court of Auditors released on June 29. These defects have set back development by five years, it believes.
The report also criticizes the Union’s 27 individual member states for counterproductive promotion of their respective national aerospace industries. The auditors conclude that the original public-private partnership plan was “inadequately prepared and conceived” and “unrealistic.”
The European Commission (EC) “must considerably strengthen its management,” advice the EC has evidently taken to heart. For the last year, contract negotiations by the European Space Agency (ESA) have taken place under the watchful eye of an EC program manager.
Contracts. On June 15, ESA signed contracts for the procurement of so-called long-lead items required for the construction of the constellation with Astrium GmbH and OHB Systems, the latter a German company and the former a German-French partnership with British involvement. Both Astrium (€7 million) and OHB (€10 million) contracts relate to parts for equipment of the satellite platforms and navigation payloads. Award of the satellite contracts themselves is planned to take place by the end of 2009.
ESA and Arianespace contracted for launch of the first four operational Galileo satellites on two Soyuz launch vehicles from Europe’s Spaceport in French Guiana. The four IOV satellites will be placed in orbit by end of 2010.
Conversations at the Paris Air Show seemed to indicate that ESA and the EC may divide the satellite construction contract into two stages to permit a later modification of the design, and that they may also divide the first satellite contract between the two bidders, Astrium and OHB, as an insurance policy to reduce the possibility of further development delays, and as a boon to design flexibility.
The Astrium CEO sharply criticized this option, saying it would increase overall program cost. The OHB CEO seemed more sanguine, lauding ESA’s move as likely to maintain a competitive environment.
The U.S. Air Force Space and Missile Systems Center (SMC) announced in late August that the long-planned upgrade of the GPS command and control system will occur during the second week of September, fulfilling a major program commitment for 2007.
Dubbed the Architecture Evolution Plan (AEP), the upgrade will replace the entire GPS master control station, including both software and hardware, some of which dates back to GPS’s inception in the 1970s. The upgrade will, among other things, begin preparing the master control station to work with the latest generation of Block IIF satellites when they go into orbit; further work with the next-generation OCX, however, will be necessary for managing M-code and the new L5.
“The delivery of SMC’s new GPS ground segment to the 50th Space Wing [will enable] transition of satellite operations from a 1970s-era GPS mainframe computer to a new server-based AEP ground segment,” said Lt. Gen. Michael Hamel, SMC Commander. “I am very proud of the team that has thoroughly tested the new system to ensure no change to the GPS signal during the changeover to the new system. The best analogy I could make is that this is like changing the engine on a car while traveling 50 miles an hour down the road.”
Col. David Madden, GPS Wing Commander, added “The replacement of the legacy system to AEP is a benefit to both the warfighter and the civil community. AEP is designed to improve operations, increase efficiency, and provide a foundation for new capabilities as they become available. The replacement from the legacy mainframe system to a distributed architecture provides the capability to command and control the next generation of GPS satellites and lays the foundation for a new security architecture to support the warfighter in the field.”
The AEP transition will take place over a period of four to six days; the total cost of the new ground control system amounts to approximately $800 million. The Air Force will not announce the exact date and time of transition, but will inform users 48 hours after completion.
The upgrade features a new satellite control foundation that replaces the legacy system and adds new digital communications. This means installing and activating a new master control station at Schriever Air Force Base which includes new hardware and software to generate navigation messages, a new system for controlling satellites, and new capability to command satellites through the Air Force Satellite Control Network (AFSCN). Adding the AFSCN will increase the number of available antennas for contacting satellites. The upgrade also involves installing and activating the alternate Master Control Station at Vandenberg AFB in California, and upgrading the current GPS ground antennas.
Ground control at Schriever AFB will phase in a few satellites in the GPS constellation at a time; the process will be completely reversible if it encounters any problems. Before it begins, both old and new ground control systems will be synchronized in terms of positioning data, namely their reception of satellites’ timing and navigation signals, down to the millimeter level. GPS users should not notice the transition, according to the Air Force.
The AEP will retain all of the legacy monitoring stations around the world currently utilized by the U.S. Air Force, as well as the National Geospatial-Intelligence Agency (NGA) monitoring stations around the globe originally added as part of the Legacy Accuracy Improvement Initiative. Additional NGA monitoring station sites are in the process of being brought online for future inclusion within the AEP.
Galileo Tests; Rescue Role
The antenna dish at Chilbolton Observatory.
The test campaign using the large antenna at Chilbolton Observatory to analyze the navigation signals transmitted by GIOVE-A, the first Galileo satellite, has been successfully completed, the European Space Agency (ESA) announced in mid-August.
Analysis of the satellite’s signals since January 2006, to verify their conformance with the Galileo system specification, has involved the Navigation Laboratory at ESA’s European Space Research and Technology Centre (ESTEC) in the Netherlands, the ESA ground station at Redu, Belgium, and the Rutherford Appleton Laboratory (RAL) Chilbolton Observatory in the United Kingdom.
Following signal analysis, operators have made some adjustments, re-programming the spacecraft’s navigation signal generation unit to compensate for changes to the signals introduced by the amplifier that boosts them for transmission to Earth and by a filter that protects adjacent frequency bands from interference.
To achieve the correct solution, the calibrated Chilbolton station was used to receive the signals from GIOVE-A. ESA’s Navigation Laboratory processed the resulting data. The signal generator manufacturer, TAS (France), calculated the new settings for the unit. Finally, the satellite manufacturer, Surrey Space Technology Limited (SSTL), uploaded the new values to the payload using their ground station at Guildford, in the United Kingdom.
According to ESA, “GIOVE-A is now transmitting optimized signals. Research and testing continues, and manufacturers are using the signals as they develop the receivers that users will need when Galileo enters operational service.”
Global Search and Rescue. Once operational sometime after 2012, Galileo will improve the detection of emergency beacons, according to program representatives whoattended the annual Joint Committee Meeting of COSPAS-SARSAT, the international program for satellite-aided search and rescue. Galileo satellites will carry transponders to relay distress signals to search and rescue organizations. Galileo partners have committed to developing a search and rescue component as an integral part of Medium Earth Orbit Search And Rescue (MEOSAR), the future worldwide search and rescue satellite system.
COSPAS-SARSAT already has systems operating in low-Earth orbit and geostationary orbit. The low-Earth orbit satellites can determine the location of emergency beacons using the Doppler effect as they pass overhead. However, there is a delay in relaying the distress signal because the satellites can only “see” a part of the Earth’s surface at any given time and a beacon is only detected when the satellite passes nearly overhead. Also, the satellites must store the location of the emergency and transmit it to a ground station once one comes into range, creating further delay.
Search and rescue transponders on geostationary satellites can constantly view a large, fixed area of the Earth, eliminating the time delay in detecting distress signals. However, they cannot automatically determine the location of the distress beacon as the low-Earth orbit system does, but must rely on the beacon to use a navigation system to find its position and include it in the distress call.
Emergency beacons require a direct line-of-sight to the geostationary satellites. There are some situations where this is impossible, such as near the Earth’s poles, where the satellites are too low in the sky, or when an accident occurs where surrounding terrain obscures the satellite.
Future Improvements. To improve performance of the overall COSPAS-SARSAT system, plans are now being made to fly search and rescue payloads on future navigation satellites. The various navigation satellite constellations will each have about 20 to 30 satellites in medium-Earth orbit, providing global coverage, including at the Earth’s poles, and with multiple viewing angles to the satellites, eliminating terrain blocking.
The Galileo search and rescue component will provide two services. The Forward Link Alert Service, backward-compatible with current COSPAS-SARSAT components and interoperable with all other planned MEOSAR elements, detects activated distress beacons and notifies the appropriate rescue body. A new Return Link Service will send a return message to the emergency beacon, notifying the emergency victims that their distress signal has been received and help is on its way.
The Galileo In-Orbit Validation Programme, which will have four satellites fitted with search and rescue transponders, will demonstrate the Galileo MEOSAR services — although its flight timetable has yet to be finalized or announced.
DOT Weighs NDGPS Future, Asks Public Input
The U.S. Department of Transportation’s (DOT) Research and Innovative Technology Administration (RITA) is preparing an assessment on the inland component of the Nationwide Differential Global Positioning System (NDGPS) that will determine its future.
As part of that assessment, it is seeking public input from users of the system.
The current expansion of the NDGPS has been placed on hold pending congressional review of the system’s funding; RITA’s assessment is part of that review. Differential GPS uses the fixed location of a reference station on the ground to improve the positioning resolution provided by civilian GPS satellite signals down to 1–3 meters. NDGPS facilities also monitor GPS satellites for anomalous behavior and issue integrity warnings when necessary.
The NDGPS program is operated jointly with the DOT’s Federal Highway Administration, Federal Railroad Administration, and Office of the Secretary of Transportation; the Department of Homeland Security’s U.S. Coast Guard; the Departmentof Commerce’s National Geodetic Survey and Forecast Systems Laboratory; and the Department of Defense’s Air Force and Army Corps of Engineers. Begun in 1997, to date there are 37 operational NDGPS sites. Two additional sites are ready for construction and could be operational in a matter of months, according to the Coast Guard.
As part of the assessment, RITA published a notice in the Federal Register addressing the current user requirements for the inland or terrestrial component of the NDGPS. This assessment is in preparation for making a recommendation to the National Space-Based Positioning, Navigation and Timing (PNT) Executive Committee, which oversees the entire GPS, on the need to continue to operate inland NDGPS and to make a decision on its future funding.
If no transportation requirements or other federal user requirements are identified as a result of the needs assessment, and if there are no other federal or other funding sources willing to sponsor or partner in sponsoring NDGPS, the DOT will develop a decommissioning plan for NDGPS, according to RITA.
The deadline for public comment is October 1, 2007. Comments may be submitted via the Internet at the Department of Transportation Web site. Instructions for other methods of submitting comments, including via postal service and fax, can also be found there in the docket management portion of the site.
The Robots of DARPA
The U.S. Defense Advanced Research Projects Agency (DARPA) has named 36 teams as semifinalists for its Urban Challenge to take place later this year.
The DARPA Urban Challenge will feature autonomous ground vehicles executing simulated military supply missions in a mock urban area. It will take place November 3at an urban military training facility located on the former George Air Force Base in Victorville, California.
The 36 semifinalists will compete in the Urban Challenge National Qualification Event (NQE), October 26–31. The top 20 teams from the NQE will move on to the Urban Challenge final event on November 3, and compete for cash prizes worth $2 million for first, $1 million for second, and $500,000 for third place.
At the NQE and the final event, the robots must operate entirely autonomously, without human intervention, and obey California traffic laws while performing maneuvers such as merging into moving traffic, navigating traffic circles, and avoiding moving obstacles. DARPA conducted competitive site visits across the United States to select the semi-finalists.
“The depth and quality of this year’s field of competitors is a testimony to how far the technology has advanced since the first Grand Challenge in 2004,” said DARPAdirector Tony Tether.
Stanford University’s winning robot vehicle from the last DARPA Challenge in 2005, which ran across the Mojave Desert, consisted of a stock Volkswagen Touareg R5 thatincorporatesd measurements from GPS, a 6DOF inertial measurement unit, and wheel speed for pose estimation.
SVN23, the first Block IIA satellite to be launched (as PRN23), has been reactivated as PRN32. This satellite was launched on November 26, 1990, and initially decommissioned on February 13, 2004, after more than 13 years of service. SVN23/PRN32 is in slot E5 and is operating on its Rb2 clock.
PRN32 was last used by SVN32. It used that code until January 28, 1993, when its code was switched to PRN01.
It is believed that SVN23 was initially reactivated with a non- standard code that cannot be tracked by standard GPS receivers. However, on December 2, it started to transmit the standard PRN32 code. Nevertheless, the satellite was set unhealthy as it reportedly had been reactivated only for test purposes.
Richard Langley provided this information in a footnote to his Navstar GPS Constellation Status report of November 4, 2006, posted to users of the CANSPACE list service (contact [email protected] to subscribe). As reported by Stephan Schaer of the Center for Orbit Determination in Europe, some “all-in-view” stations of the IGS tracking network (which can track both healthy and unhealthy satellites) began receiving SVN23/ PRN32 signals on December 2. However, it seems that some manufacturers’ receivers were unable to track a satellite with a PRN number of 32.
On December 7, the GPS Operations Center at Air Force 2nd Space Operations (2SOPs) issued this Notice Advisory to Navstar users (NANU): “An initial assessment period for SVN 23 utilizing PRN 32 was accomplished 1 December to 6 December 2006; SVN 23 is no longer transmitting L-band.
“During this assessment period SVN 23 was broadcasting L-band and set unhealthy. SVN 23 was not included in the operational constellation almanac.
“Any users that experienced unusual performance from GPS user equipment during this period should contact the GPS Operations Center.
“Approximately 10 January 2007, SVN 23 utilizing PRN 32 will be turned on; transmitting L-band and kept unhealthy. SVN 23 will still not be included in the operational constellation almanac. The GPS Operations Center will transmit a General NANU reminding users of this activity.”
Testing, Testing. As reported in the November, 2006 issue of this magazine, the Air Force issued an earlier memorandum stating that the November 17 launch of SVN58/PRN12 would set a new mark of 31 operational satellites, and that operational control could go beyond 32 satellites. As most current civil receivers are set at 31, this has important ramifications that manufacturers should consider.
The GPS Operations Center continues to seek feedback on potential impacts the largest-ever GPS constellation may have on users and equipment. “Although future versions of our interface spec, IS-GPS-200, will accommodate a larger constellation for the next-generation GPS, the most pressing concern is with potential impacts to existing fielded GPS receivers that may not properly account for up to 32 operational PRNs.”
The early December and January L-band broadcasts by SVN 23 may represent tests to assess various aspects of that future eventuality.
This One’s for Real. Meanwhile, the new GPS IIR-M satellite SVN58/ PRN12 was declared operational on December 13.
Galileo Guess Who
EU States Vie to Host Supervisory Authority
No fewer than eleven European Union (EU) member states have their hands in the ring to grab hosting of the Galileo Supervisory Authority, tasked to take over from the Galileo Joint Undertaking on January 1, 2007, and manage the EU satellite navigation program. Ministerial meetings among the candidate states could not resolve the matter, nor could the EU leaders’ summit, December 11-12, make the politically charged decision.
Deliberations were postponed until the incoming German presidency in January and the next Transport Council meeting in February. Discussion focused on whether the decision should respect an agreement reached in 2003 providing for the new member states to be given priority in hosting new agencies.
Race Card. Eleven countries have ponied up their candidate sites: Belgium (Brussels), the Czech Republic (Prague), France (Strasbourg), the Netherlands (Noordwijk), Italy (Rome), Malta (Valetta), Germany (Munich), Greece (Athens), Slovenia (Ljubljana), the United Kingdom (Cardiff), and Spain (Barcelona).
According to the EU protocol, new “decentralized” agencies should go to new member states, that is, predominantly those in Eastern Europe. Only Poland currently hosts one of these, and all the founding 15 states already have an agency. So, presumably, Malta, Slovenia, and the Czech Republic would appear to have pole position. They are truly dark horses, however, as national contributions to the Galileo budget run much higher in the industrialized, space-age West, and these commitments come with significant quid pro quo.
Security. Concern has surfaced from some old member states about the security of the site, since the agency will oversee highly sensitive information. The Czech Republic is making a particularly strong push for host designation, witha Czech spokesperson later stating “Prague has fulfilled the security conditions.” Angered by the debate — which may or may not represent a stalking horse for more real economic motives — the Czechs could block a move to host in an old member state city, with the UK’s Cardiff seen a strong candidate. Germany and France have already landed plum Galileo sites, and Italy and Spain have secured backup/secondary hostings. Only the UK, of the Galileo Big Five, remains out in the cold.
Agency hosting brings jobs, direct economic benefits, and enhanced prestige. It also entails correlative conference hosting attracting international participation — and closer contact for national industry that could lead to further contracts.
Governments compete by offering the best buildings with desirable, largely metropolitan locations, and requiring only token rent. The model was set in this regard a few decades ago, when a farsighted mayor of Noordwijk, the Netherlands, offered a substantial plot of ground virtually free to the nascent European Space Agency (ESA).
Whether the EU will stick to its principles or opt pragmatically remains to be seen. Meanwhile, some observers recall Italian prime minister Silvio Berlusconi’s pouting when the EU food agency appeared headed for Helsinki: “They don’t know prosciutto” — or words to that effect.
The agency ended up in Parma.
GPS III Faucet Opened
$50M Design Contracts Awarded
Co-competitors Lockheed Martin Space Systems Corp. and Boeing Co. each received a $49,999,000 cost-plus-fixed fee contract modification to accomplish a GPS III system design review (SDR) in March 2007, towards a key decision point B in June, 2007: the award of a multi-billion dollar development contract for building GPS III. Headquarters Global Positioning Systems Wing, Los Angeles Air Force Base, California, is the contracting entity. Lockheed Martin leads a team that includes ITT and General Dynamics.
The next-generation GPS Block III “will address the challenging military transformational and civil needs across the globe, including advanced anti-jam capabilities and improved system security, accuracy, and reliability.”
In early 2005, the GPS III program was restructured from an FY12 first launch to no later than an FY13 first launch.
In September, 2006, the U.S. Air Force announced plans to offer a “healthy incentive” to the prime GPS III contractor for launching the first III satellite in 2011, instead of the current projected 2013 date. Lieutenant General Michael Hamel, Commander, Space and Missile Systems Center, stated “We believe speed-to-market is a key element of our future success.”
GPS III contract incentive fees will shift from qualitative to a quantitative basis, structured around cost, schedule, and technical performance.
Co-competitors Lockheed Martin Space Systems Corp. and Boeing Co. each received a $49,999,000 cost-plus-fixed fee contract modification to accomplish a GPS III system design review (SDR) in March 2007, towards a key decision point B in June, 2007: the award of a multi-billion dollar development contract for building GPS III. Headquarters Global Positioning Systems Wing, Los Angeles Air Force Base, California, is the contracting entity. Lockheed Martin leads a team that includes ITT and General Dynamics.
The next-generation GPS Block III “will address the challenging military transformational and civil needs across the globe, including advanced anti-jam capabilities and improved system security, accuracy, and reliability.”
In early 2005, the GPS III program was restructured from an FY12 first launch to no later than an FY13 first launch.
In September, 2006, the U.S. Air Force announced plans to offer a “healthy incentive” to the prime GPS III contractor for launching the first III satellite in 2011, instead of the current projected 2013 date. Lieutenant General Michael Hamel, Commander, Space and Missile Systems Center, stated “We believe speed-to-market is a key element of our future success.”
GPS III contract incentive fees will shift from qualitative to a quantitative basis, structured around cost, schedule, and technical performance.
Modern Space Receiver
ITT Corporation and General Dynamics each received a contract from the GPS Wing to develop a modernized space receiver (MSR) to operate in space on low-earth orbit satellites and capable of receivng new, modernized GPS signals. Each will prepare a proposal for full-scale development of the MSR, to be presented to the GPS Wing in mid-2007, and one will be chosen to complete the project.
