GPS World

Tag: LightSquared

  • The System: Second Report by LightSquared/GPS Technical Working Group Maps Terrain, Does Not Yet Explore

    Plus: GLONASS CDMA Tracked, Third Beidou-2 Launched

    The second report from non‐governmental members of the LightSquared/GPS Technical Working Group (TWG) was filed with the Federal Communications Commission (FCC) on April 15. For those anxious to see actual results of interference/desensitization of GPS receivers by the proposed LightSquared terrestrial signal — or, conversely, absence of said results — the report does not contain any such hard news. It relates the set-up of TWG work sub-teams to test various categories of GPS devices and receivers.

    The sub-teams have identified laboratories for testing activities, developed test plans, and identified devices, receivers, and systems to be tested. Attachments to the report include current draft test plans and the current list of devices and receiver models submitted for testing by companies.

    The following sections summarize the testing laboratories and devices selected for testing by each sub-team:

    • aviation
    • cellular
    • general location/navigation
    • high precision, networks, and timing. These three sub-teams are collaborating to a large extent.
    • space-based receivers.

    The full report also includes a “high-level description of test plan” by each sub-team.

    Aviation Sub‐Team. The aviation sub‐team will rely primarily on testing, funded by the Federal Aviation Administration (FAA), that will be performed at Zeta Associates Incorporated of Fairfax, Virginia.

    Additional testing is planned by the U.S. government at White Sands Missile Range and Holloman Air Force Base, both in New Mexico, for use by the National PNT Engineering Forum (NPEF) LightSquared Working Group. These results will be considered for inclusion in the TWG Final Report by the aviation sub‐team. Presumably, this group will test military receivers, under classified categorization.

    The aviation receivers are representative of those in use today. Their selection was based mainly upon device availability (those already owned by the FAA Technical Center). They are: Canadian Marconi GLSSU 5024; Garmin 300XL; Garmin GNS 430W; Garmin GNS 480; Rockwell Collins GLU‐920 multimode receiver; Rockwell Collins GLU‐925 multimode receiver; Rockwell Collins GNLU‐930 multimode receiver; Symmetricomm timing card (used for an FAA automation system); WAAS NovAtel G‐II ground reference station; and Zyfer timing receiver (used for the WAAS ground network).

    Cellular Sub‐Team. The cellular sub‐team is in the process of engaging PC TEST, Columbia, Maryland; CETECOM, Milpitas, California; InterTek, Lexington, Kentucky; and ETS Lindgren, Cedar Park, Texas, for device testing.

    The cellular sub‐team expects to test approximately 50 different device models. The selections represent current and legacy devices and have been prioritized based on sales volumes. While it is expected that there will be some representation of data‐only devices and femtocells, the testing will focus largely on handheld devices.

    Those designated for testing are: Apple iPhone 4 (GSM and CDMA); HTC A6366; HTC ADR6200; HTC ADR63002; HTC ADR63003; HTC ADR6400L; HTC Touch Pro 2; LG Lotus Elite; LG Rumor Touch; LG VN250; LG VS740; LG VX5500; LG VX5600; LG VX8300; LG VX8360; LG VX8575; LG VX9100; LG VX9200; Motorola A855; Motorola DROID X; Motorola VA76R; Motorola W755; Nokia 6650; Nokia E71x; RIM 8330C; RIM 8530; RIM 9630; RIM 9650; RIM 9800; Samsung Moment; Samsung SCH‐U310; Samsung SCH‐U350; Samsung SCH‐U450; Samsung SCH‐U640; Samsung SCH‐U750; Samsung SGHi617; Samsung SGHi917; Sierra Wireless 250 U USG 3G/4G; and Sony Ericsson W760a.

    General Location/Navigation. This sub-team has chosen Alcatel/Lucent as its initial facility for testing. Twenty-six devices were selected based on nominations by manufacturers represented on the sub‐team, considering the percentage of the installed user base.

    They include: Garmin Forerunner 110 and 305; Garmin ETREX‐H; Garmin Dakota 20; Garmin Oregon 550; Garmin GTU 10; BI Inc. ExacuTrack One; Garmin GPS 17X; Garmin GPSMAP 441; Hemisphere Vector MV101; GM OnStar (model TBD); Garmin GVN 54; TomTom XL335; TomTom ONE 3RD Edition; TomTom GO 2505; Garmin nűvi 2X5W, 13XX, 3XX, and 37XX; Garmin GPSMAP 496; Garmin aera 5xx; Honeywell Bendix/King AV8OR; Trimble iLM2730; Trimble TVG‐850; Trimble Placer Gold; and Hemisphere Outback S3.

    High Precision-Networks-Timing. The HPN&T sub‐teams are collaborating extensively to develop joint test plans and procedures. The joint sub-teams have chosen the U.S. Navy’s NAVAIR facility for testing.

    To be tested are: Hemisphere R320; Hemisphere A320; Deere iTC; Deere SF‐3000; Deere SF‐3050; Trimble MS990; Trimble MS992; Trimble AgGPS 252, AgGPS 262, AgGPS 442, and AgGPS EZguide 500; Trimble CFX 750; Trimble FMX; Trimble GeoExplorer 3000 series GeoXH and GeoXT; Trimble GeoExplorer 6000 series GeoXH and GeoXT; Trimble Juno SB; Trimble NetR9 and NetR5; Trimble R8 GNSS; Trimble 5800; Leica SR530; Leica GX1200 Classic; Leica GX1230GG; Leica GR10; Leica Uno; Leica GS15; Topcon HiPer Ga and HiPer II; Topcon GR‐3 and GR‐5; Topcon MC‐R3; Topcon NET‐G3A; Topcon TruPath/AGI‐3; NovAtel PROPAK‐G2‐Plus; NovAtel FLEXG2‐STAR; NovAtel FLEXPAK‐G2‐V1, FLEXPAK‐G2‐V2 and FLEXPAK6; NovAtel PROPAK‐V3; NovAtel DL‐V3; Septentrio PolaRx3e; and Septentrio AsteRx3.

    Timing receivers: FEI‐Zyfer UNISync GPS/PRS; TruePosition GPS timing receiver; Symmetricom SSU 2000 (Motorola M12M); Symmetricom Time Provider 1000/1100 (Furuno GT‐8031); Symmetricom TimeSource 3500 (XR5 (Navstar/Symmetricom); Trimble Resolution T; Trimble Accutime Gold; Trimble Resolution SMT; Trimble MiniThunderbolt; NovAtel OEMStar; NovAtel OEM4; and NovAtel OEMV3.

    Space‐Based Receivers. Lab testing has been conducted at the NASA Jet Propulsion Laboratory (JPL) in California. The receivers are used by NASA for space‐based missions and high-precision science applications. The TWG agreed that these would be tested at JPL by NASA, with participation by LightSquared personnel, and the results provided to the TWG; see Appendix G

    The devices tested are current or representative of GPS receivers in use by NASA or planned for use in the near future for space and science applications: TriG (NASA Next‐generation Space Receiver) and IGOR (Space Receiver).

    NASA/JPL also tested the following high-precision receivers and shared the results with the HPT&N sub‐team: JAVAD Delta G3T (High Precision‐IGS) and Ashtech Z12 (High Precision‐IGS).

    Conclusion. For all sub-teams, analyses will consider both LightSquared’s expected transmit power of 62 dBm per channel and its maximum authorized transmit power of 72 dBm per channel.

    The WG co‐chairs will update the Commission on its progress in a subsequent report on May 16.

    The April 15 TWG report contains these appendices: Working Group Roster; List of Receivers and Devices; Aviation Test Procedure; Cellular Test Plan Draft; General Location/Navigation Test Plan Draft; High Precision/Networks/Timing Test Plans Draft; Space‐Based Receivers Test Process.

    GLONASS CDMA: New Era’s Dawn Glimpsed from Multiple Receivers

    The newest Russian satellite, launched on February 26, began transmitting its new code-division multiple-access (CDMA) signal on April 7. In a clear break from all previous GLONASS signals, which are frequency-division multiple-access (FDMA), the new signal is expressly designed to be interoperable with current and future GPS signals, and with the coming Galileo signals, all of which have a CDMA structure. Thus, a new era of GNSS, truly global navigation satellite systems, began on April 7.

    JAVAD GNSS was the first company to announce that it had tracked CDMA signals of the GLONASS-K satellite in
    the L3 GLONASS band. Data was logged at the company’s Moscow office on April 8 from 02:30 until 07:30 UTC. The satellite’s pseudorange (in chips) and signal-to-noise ratio (in relative numbers) are shown in Figures 1 and 2.

    Figure 1. GLONASS-K’s pseudorange in chips, courtesy of JAVAD GNSS. The y-axis goes from 0 to 12,000 in increments of 2,000; the x-axis goes from 0 to 500 in increments of 100. (Click to enlarge.)
    Figure 2. GLONASS-K’s signal-to-noise ratio (in relative numbers), courtesy of JAVAD GNSS. The y-axis goes from 0 to 10,000 in increments of 2,000; the x-axis goes from 0 to 500 in increments of 100. (Click to enlarge.)

    On April 11, the satellite’s code-minus-phase and signal-to-noise ratio were tracked (Figures 3 and 4). Data quality is quite similar to GPS, according to the company.

    Figure 3. GLONASS-K satellite’s code-minus-phase data (courtesy of JAVAD GNSS). (Click to enlarge.)
    Figure 4. GLONASS-K satellite’s signal-to-noise ratio (courtesy of JAVAD GNSS). (Click to enlarge.)

    Future GLONASS satellites of the K1 and subsequent K2 generations will broadcast CDMA signals in multiple frequency bands. GLONASS-K satellites are markedly different from their predecessors. They are lighter, use an unpressurized housing (similar to that of GPS satellites), have improved clock stability, and a longer, 10-year design life. There will be two versions: GLONASS-K1 will transmit a CDMA signal on a new L3 frequency, and GLONASS-K2 will in addition feature CDMA signals on L1 and L2 frequencies. The CDMA signal in the L3 band has a center frequency of 1202.025 MHz.

    The new generations of GLONASS signals and satellites are described in detail in the April “Innovation” column of GPS World, edited by Richard Langley.

    Septentrio Navigation of Leuven, Belgium, also tracked GLONASS CDMA L3 signal with its AsteRx3 receivers. Figure 5 shows the C/N0 in dB-Hz of the legacy L1-C/A signal and of the data component of the new L3 CDMA signal. The graph covers the time span starting at 20:30 (UTC) on April 10 and ending at 02:00 on April 11. Figure 6 shows the de-trended code minus phase from L1-C/A and L3 signals. Such a plot provides a glimpse of the code measurement multipath and noise, according to the company.

    Figure 5. GLONASS-K1 AsteRx3 measurements; C/N0 in dB-Hz of L1-C/A and L3 CDMA (courtesy of Septentrio Navigation).
    Figure 6. GLONASS-K1 AsteRx3 measurements; de-trended code minus phase of L1-C/A and L3 CDMA (courtesy of Septentrio Navigation).

    Topcon Positioning Systems (TPS) also released data on the new signal, stating that signals from the new satellite “provide an additional accuracy advantage over older satellites.” Figures 7 and 8 show data from the company’s Moscow office.

    Figure 7. Pseudorange-phase of four signals transmitted by the new K1 satellite (courtesy of Topcon Positioning Systems). (Click to enlarge.)
    Figure 8. Signal-to-noise ratios of four signals transmitted by the new K1 satellite (courtesy of Topcon Positioning Systems). (Click to enlarge.)

    Finally, the German Aerospace Center’s Institute of Communications and Navigation recorded the spectrum of the GLONASS CDMA signal, captured with a 25-meter dish antenna, Raisting Satellite Earth Station, near Munich.

    The signal spectrum spans at least 40 MHz (Figure 9). It contains additional sidelobes not shown in the plot. The plot indicates total power of all components of the transmitted signal.

    Figure 9. GLONASS CDMA signal’s power over frequency (courtesy of the German Space Agency, DLR).

    Third Beidou-2 IGSO Launched

    China’s BeiDou-2 (Compass) satellite launched on April 9 has attained a circularized orbit, joining two inclined geosynchronous orbit (IGSO) satellites to form a mini-constellation centered on an east longitude of about 120 degrees. While BeiDou-IGSO-3’s orbit might still be tweaked slightly, it is clear that the orbits of the three satellites are arranged so that there will always be one satellite with a high elevation angle over China, according to the CANSPACE news service operated by the University of New Brunswick.

    The latest spacecraft joins four geostationary satellites, a middle-Earth orbiting vehicle, and the two other IGSO satellites now on orbit. As the first Chinese launch in 2011, the new arrival presages much activity to come. With eight now flying, six more spacecraft are scheduled to rise by 2012, completing a 14-satellite constellation to provide a regional service over eastern Asia. The regional system will consist of five geostationary or GEO, five IGSO, and four medium-Earth orbit satellites.

    Long-range plans envision a 35-satellite constellation providing global service by 2020: 27 MEOs, 5 GEO satellites, and 3 IGSOs. The satellites will transmit signals on the 1195.14–1219.14 MHz, 1256.52–1280.52 MHz, 1559.05–1563.15 MHz, and 1587.69-1591.79 MHz carrier frequencies.

    Compass satellites have an announced lifespan of eight years.

    Three IGSO satellite tracks over China (image courtesy of CANSPACE).

     

  • The System: First GPS Intereference Report Sent to FCC

    First Overload Interference/Desensitization to GPS Receivers, Systems, and Networks Report to FCC

    The joint working group co-led by the U.S. GPS Industry Council and Lightsquared, investigating potential problems of LightSquared/GPS interference, delivered its first monthly report on March 15 as directed by the FCC. The report (PDF) lays out a schedule for receiver selection and testing and names 34 members, two working group co-chairs, and four information facilitators of a technical working group (TWG) supervising and analyzing the assessment of GNSS receivers operating under conditions of a dense national network of high-powered cell-phone transmitters. “TWG members represent a diverse group of interested parties including equipment and chipset manufacturers, aerospace/aviation companies, wireless providers, engineering firms, public safety, and various federal agencies. Additionally, several individuals have volunteered to be advisors to the TWG,” said the report.

    The TWG held its first meeting on March 3 in Arlington, Virginia, and via a conference bridge for members around the globe who were unable to attend in person. In that and subsequent teleconferences, the TWG focused on the first seven items from the Work Plan:

    Establish pertinent analytical and test methodologies and assumptions underlying the test regime: definition of harmful interference, relevant information regarding terrestrial broadband network, interference analysis assumptions, and evaluation of potential test methodologies.

    • Select categories of receivers and receivers to be tested.
    • Develop operational scenarios.
    • Establish methodology for analyzing test results.
    • Derive test conditions based on the established operational scenarios.
    • Write test plan and procedures.
    • Identify and engage appropriate test facilities.

    LightSquared provided technical details to the TWG regarding the equipment planned for its terrestrial broadband deployment, including the channelization plan, output power, out-of-band emission (OOBE) characteristics, and emissions mask.

    The GPS community is concerned that desensitization/overload due to strong signals outside of the GPS band may cause GPS receivers to operate in a non-linear mode with reduced gain (that is, gain compression) for the desired GPS signal. Other receiver impairments may also arise as a result of the nearby strong signals.

    The TWG has agreed to move forward with a combination of laboratory-based and field-based testing programs. Field testing will be performed at outdoor test locations using transmitters, filters, and antennas similar to those that LightSquared plans to deploy in its commercial operations.

    Other items of interest in the report:

    Definition of Harmful interference at the GPS/GNSS/Augmentations/L-Band Receiver. “The TWG members have discussed a number of receiver parameters related to the definition of harmful interference. In the FCC Rules, harmful interference is defined as ‘interference which endangers the functioning of a radionavigation service or of other safety services or seriously degrades, obstructs, or repeatedly interrupts a radiocommunication service operating in accordance with [the ITU ] Radio Regulations.’

    “Harmful interference affects different types of receivers in different ways. The key factors that pertain to the functioning of GPS receivers and/or whether service is degraded, obstructed, or interrupted are accuracy (position, velocity, time), availability (ability to perform a given function), coverage (within what space can a function be performed), integrity (what is the probability that the results are correct), and continuity (what is the probability that a given function can be completed). Metrics for harmful interference are developed from an understanding of the consequential relationship between negative impacts and receiver parameters, which include effective C/N0, PVT accuracy, time to first fix, loss of lock, cycle slips, etc. The signal conditions to be taken into account are defined in the GPS Standard Positioning Service (SPS) Performance Standard, 4th Edition, Interface Specifications (ISs), GPS policy, and both the present and planned future signal environments will be considered.Environmental and field conditions in which GPS receivers operate will also be considered.

    “It should be possible to assess interference impact, up to that which includes harmful interference, using metrics in terms of receiver parameters that include measurable changes in effective C/N0 as well as position accuracy, time to first fix, loss of lock, cycle slips, etc. Related to this discussion is whether there is any margin that could be budgeted for terrestrial broadband operation, and if so, what that amount could be. When considering systems guaranteed for safety-of-life operations, there may be very little or no margin.

    “There is general agreement within the TWG that the device testing protocols should include changes in effective C/N0 and degradation of other key performance measures so as not to exclude data that might be relevant for the post-testing analytical phase using operational scenarios.

    Overload interference/desensitization at the GPS/GNSS/Augmentations/L-band Receiver. “Desensitization/overload due to strong signals outside of the GPS band may cause the GPS receiver to operate in a non-linear mode with reduced gain (i.e., gain compression) for the desired GPS signal; there may also be other receiver impairments caused by strong signals outside the GPS band. The TWG will consider these mechanisms further after testing is underway and sufficient samples are available to adequately assess such mechanisms.”

    Evaluation of Potential Test Methodologies. “The TWG has agreed to move forward with a combination of laboratory-based and field-based testing programs. Laboratory tests are repeatable, allow for the creation of a fully controlled environment and the ability to test multiple scenarios and many devices in an efficient, repetitive manner. Field tests expose devices to a real-world environment where measurements can be performed at various distances and morphologies from terrestrial broadband network sites in order to gauge the effects of distance and physical environments on terrestrial broadband signal strength and potential interference. One advantage of field testing is that it captures a complete, live test environment comprehensively and helps develop keener testing or analysis insights that modeling cannot offer. The major disadvantage or concern is that field testing uses the present environment, not the environment that might exist at some future or past time. Interference testing analysis has to consider worse-case assumptions, and not only the current test reality.

    “Laboratory testing will be performed either using conducted testing, where devices are connected directly to transmission sources via 50 ohm connectors, or through radiated testing in anechoic or other radiated emissions chambers. While conducted testing is the preferred laboratory methodology, anechoic chambers will be used where conducted testing is not practical, is not recommended by the manufacturer, or where connectorized devices cannot be made available within the established test timeline.

    “Field testing will be performed at outdoor test locations that will utilize transmitters, filters, and antennas similar to those that will be deployed by Lig
    htSquared in its commercial operations.”

    The TWG identified seven categories of receivers that it considers representative of non-military GPS user equipment operating in the United States: aviation, cellular, general location/navigation, high precison, timing, space-based receivers, and networks.

    Seven sub-teams are focusing on these receiver categories. The sub-teams are responsible for determining device selection and prioritization criteria, defining operational scenarios, listing testing conditions and test plan procedures, and recommending appropriate test facilities.

    Save Our GPS Coalition Forms

    Representatives from a variety of industries and companies have formed the Coalition to Save Our GPS to resolve what it terms a serious threat to the national positioning, navigation, and timing service: the FCC conditional waiver to Lightsquared allowing expansion of terrestrial use of the satellite spectrum immediately neighboring that of GPS, potentially causing severe interference to millions of GPS receivers.

    “GPS is essential to Americans every day — it’s in our cars, the airplanes in which we fly and the ambulances, police cars, and fire trucks that help keep us safe. It’s also used in many industrial applications and even synchronizes our wireless, computer, and utility networks,” the group stated. “LightSquared’s plans to build up to 40,000 ground stations transmitting radio signals one billion times more powerful than GPS signals as received on earth could mean 40,000 ‘dead spots’ — each miles in diameter — disrupting the vitally important services GPS provides.”

    The Coalition (www.SaveOurGPS.org) includes representatives from aviation, agriculture, transportation, construction, engineering, surveying, and GPS-based equipment manufacturers and service providers.

    Initial members of the coalition are the Aeronautical Repair Stations Association, Air Transport Association, Aircraft Owners and Pilots Association, American Association of State Highway and Transportation Officials, American Rental Association, Associated Equipment Distributors, Association of Equipment Manufacturers, Case New Holland, Caterpillar Inc., Edison Electric Institute, Esri, Garmin, General Aviation Manufacturers Association, Deere & Company, National Association of Manufacturers, OmniSTAR, and Trimble. More members are expected to join in the near future.

    The following is from a statement issued by the coalition:

    “[In] The unusual waiver granted in January to LightSquared by the FCC . . . the usual FCC process of conducting extensive testing followed by approvals was not followed. Instead, the process was approve first, then test. Additional safeguards are needed, so the coalition recommends:

    “The FCC must make clear, and the NTIA must ensure, that LightSquared’s license modification is contingent on the outcome of the mandated study. The study must be comprehensive, objective, and based on correct assumptions about existing GPS uses rather than theoretical possibilities.

    “The FCC should make clear that LightSquared and their investors should not proceed to make any investment in operating facilities prior to a final FCC decision (or at least make it explicit that they do so at their own risk). While this is the FCC’s established policy, it failed to make this explicit in its order.

    “Further, the FCC’s, and NTIA’s, finding that ‘harmful interference concerns have been resolved’ must mean ‘resolved to the satisfaction of preexisting GPS providers and users.’ Resolution of interference has to be the obligation of LightSquared, not the extensive GPS user community of millions of citizens. LightSquared must bear the costs of preventing interference of any kind resulting from operations on LightSquared’s frequencies.

    “This is a matter of critical national interest. There must be a reasonable opportunity for public comment of at least 45 days on the report produced by the working group.”

    WAAS Official Again

    The Federal Aviation Administration (FAA) announced on March 18 that WAAS PRN 135 has resumed normal operations. “The WAAS team recently received the final report from Lockheed Martin on the failure of Galaxy 15,” reported FAA GNSS program manager Leo Eldredge. “After a review of that report, the team determined that the satellite was ready to be returned to operations.”

    The FAA said that PRN 135 is currently located at ~120°W and enroute to its final destination of 133.1°W, but is now broadcasting operational corrections that can be used by both aviation and ground users, including those in Northwest Alaska.

    In April 2010, satellite operator Intelsat reported it had lost contact with PRN 135 (named Galaxy 15) and it was drifting uncontrolled. At that time, the FAA reported that it would drift out of WAAS service within a few weeks. Instead, PRN 135 remained within a usable condition/location, although drifting east, until December 2010, when it ceased operating. On December 23, Intelsat reported that the power from the Galaxy 15 battery completely drained during its loss of Earth lock and the baseband equipment command unit reset, as it was designed to do. Shortly thereafter Galaxy 15 began accepting commands, and Intelsat engineers began receiving telemetry in the operations center.

    Intelsat determined that static electricity charge caused the initial failure, and has uploaded new software to prevent the event from occurring again. There are now three operational WAAS GEO satellites:

    ◾ PRN 133 located at 98°W.

    ◾ PRN 135 located at 133.1°W (currently at ~120°W); will arrive at 133.1°W on or about April 4, 2011.

    ◾ PRN 138 located at 107.3°W.

    EGNOS SOL Operational

    The European Geostationary Navigation Overlay Service (EGNOS) was declared operational for safety-of-life (SOL) services on March 2. The service consists of GPS corrected signals intended for transport applications, particularly aviation, where lives could be endangered if the performance of the navigation system is degraded.

    The SOL coverage area, expected performances, and conditions of use are described in the EGNOS Safety-Of-Life Service Definition Document (SDD, see env-gpsworld-integration.kinsta.cloud/egnosSOL). The two operational EGNOS satellites — Inmarsat-3-F2/AOR-E at 15.5 degrees west longitude using PRN code 120, and Artemis at 21.5 degrees east longitude using PRN code 124 — now transmit Message Type 2, indicating that the signals are available for safety-critical purposes.

    Air-navigation service providers can now publish SBAS precision approach procedures, localizer performance with vertical guidance (LPV), based on EGNOS. On March 22, EGNOS operator European Satellite Services Provider published the first EGNOS LPV approaches for use at Pau Airport, near the Pyrénées in southern France.

    EGNOS improves accuracy and provides integrity to the GPS signal over most of Europe and parts of North Africa. The system uses a monitoring network of 40 ground stations to provide the corrections with 99.9 percent availability over the core service region. Accuracy is measured by GPS user equivalent range error typically about 4.2 meters after EGNOS corrections for GPS signals from satellites at a 5-degree elevation, and 2.4 meters for satellite signals arriving from a 90-degree elevation. If reliability falls below a minimum level, EGNOS users are alerted within six seconds.

    Russian SBAS Satellite Passes Transponder Tests

    The Luch-5A geostationary communication satellite under construction has successfully completed a cycle of transponder tests. The satellite includes a transponder for the System for Differential Correction and Monitoring (SDCM), the Russian satellite-based augmentation system. SDCM will provide integrity monitoring of
    GPS and GLONASS satellites and differential corrections and analyses of GLONASS performance: real-time differential corrections with horizontal accuracy of 1–1.5 meters, vertical of 2–3 meters.

  • Out in Front: Dual Use, Single Front

    As it was in the beginning, now and always, and to the ages of ages — or at least into the conceivable near future: GPS was, is, and shall be a dual-use system.

    Why, then, reading through the March 15 report of the Technical Working Group (TWG) to the FCC on LightSquared/GPS interference, do we find no mention at all of military receivers?

    Presumably DoD and the GPS Directorate are both concerned and active on a separate front vis à vis the FCC, but what/how/when? Would it not be beneficial for the dual uses to present a united front in some way, or at least to collaborate to some extent? To observe, if nothing else, each other’s testing?

    It turns out there are separate LightSquared/GPS Industry Council and government testing structures, the latter under under the National Space-Based PNT Systems Engineering Forum (NPEF), which will include military receiver tests. Several government members of the TWG are also members of the NPEF. The Executive Secretariat to the NPEF is also a core member of the TWG.

    The two testing groups collaborate and try to be on the same page as to technical assumptions, test methodology, measures of effectiveness, and so on. They will observe and participate in each other’s tests as much as they can — with the exception of national security issues.

    Testing of the military receivers is not a part of the TWG primarily because of classification. Any discussion of vulnerabilities of military equipment is generally classified at least at the Secret level.

    Outside of the TWG, there have been direct meetings between LightSquared and the military officers leading the military receiver testing. The military have asked technical questions and LightSquared has answered them and provided examples of its hardware. LightSquared has flown technical experts to Colorado Springs to meet with HQ Air Force Space Command test leads.

    “To the maximum extent possible,” said Anthony Russo, director of the U.S. National Coordination Office for Space-Based Positioning, Navigation, and Timing, “we’ll invite LightSquared to review test plans and make inputs on test methodology, but we do anticipate that some of the end results will be classified and therefore have to be conveyed separately to the FCC.”

    “There is certainly good collaboration between the LightSquared-led TWG and the independent federal testing activities I directed under the NPEF charter. LightSquared has been extremely cooperative in supporting this,” he added.

    In addition to classification issues, there are other reasons to do independent federal testing. LightSquared is focusing on the potential in-band overload issue, while the GPS community is concerned about any potential interference scenario — including out-of-band emission issues that LightSquared is not looking at.

    Russo anticipates at least two reports will go to the FCC in June: “One from LightSquared where we make inputs, but have no official say on what they conclude; and one from me, based on NPEF results, submitted through the PNT EXCOM to the FCC. I expect the latter report to be at the Secret level, although we may be able to do a redacted version for LightSquared and the general public.”

  • LightSquared Saga, and Recent Solar Activity

    This week I’m following up on my article from a couple of weeks ago about the potential effects of LightSquared’s plans. As a user of high-precision GPS receivers (particularly GPS L1 sub-meter, but also dual-frequency), you should be particularly concerned about this issue. I’ll tell you why. Also, I have a note on recent the solar activity.

    LightSquared

    The reasons you should be concerned about LightSquared’s plans are two-fold:

    1. Consumer GPS receivers and professional-grade GPS receivers designed for higher performance (mapping, surveying, etc.) aren’t necessarily designed the same way. High-performance GPS receivers use a wider bandwidth radio design.

    For example, the GPS L1 frequency is 1575.42 MHz. Many high-performance GPS receivers use a wide bandwidth radio that scans +/- 20 MHz from 1575.42 MHz. That equates to a range of 1555 MHz to 1595 MHz. LightSquared’s frequency spectrum is 1525 MHz to 1559 MHz. Clearly, there’s overlap, which is another word for interference. On top of that, LightSquared plans on a broadcast strength of 1,500 watts from a tower located down the street. The GPS broadcast signal strength is about 30 watts from a satellite located some 19,000 kilometers away in outer space. Who’s going to win that battle?

    I’m not an aerospace engineer or an RF (radiofrequency) engineer, but I don’t think it takes one to see the potential impact of LightSquared’s service on high-performance GPS receivers. At the very least, it warrants an in-depth technical study.

     

    2. Neither the policymakers nor LightSquared know about or understand the user community of high-performance GPS receivers comprised of hundreds of thousands of high-end GPS receivers. They think the GPS user community is comprised of auto navigation and mobile-phone users. They don’t understand that we are the infrastructure people. We use GPS in a way that they don’t understand, but is so critical to our infrastructure. It’s not their fault, but you can’t assume they know, so it’s up to us to inform them. You have to speak up.

    Here’s a perfect example. Click on the following link to view a report presented by LightSquared last week in Taipei, Taiwan, at a 3GPP conference.

    “Final Report on Overload Characteristics of GPS Receivers in Proximity to LightSquared’s L-band Terrestrial Base Stations (BTS) and User Equipment (UE)”

    The best part about this report is the following statement from the Executive Summary:

    “Although results have been provided to date of a limited number of devices (6), LightSquared proposes to close the study at this stage as a more comprehensive study, covering a wider variety of GPS receivers than those involved in cellular applications, has now been initiated under the auspices of the FCC [2].  This study will be conducted by a cross-industry group led by LightSquared and USGPSIC, the reports of the study having complete public visibility.”

     

    Granted, I understand the Taipei conference was focused on the impact of LightSquared’s plan on mobile phones using GPS, but if this is the extent of their testing, it’s alarming. Furthermore, it’s relatively easy to acquire and operate an inexpensive consumer GPS receiver. Can you picture LightSquared attempting to test a sub-meter GPS L1 receiver or a RTK setup? GPS, GLONASS, SBAS, DGPS, real-time, post-processing, and the myriad of receivers on the market need to be tested. Although it’s likely not possible to test all equipment on the market, it’s not prudent to leave anything to chance. If, one year from now, you wake up and find out your $10,000 RTK receiver doesn’t work like it used to, it will be too late to do much about it. It takes very little time to voice your concern now to your elected officials so the appropriate attention is given to high-precision users.

    The good news is that Trimble Navigation is involved, along with the Federal Aviation Administration, with the U.S. GPS Industry Council and will be working closely with LightSquared in a Technical Working Group to better understand the impact that LightSquared’s system would have on GPS. Trimble and the FAA aren’t the only parties involved in the working group, but they are the parties that understand the needs of the high-precision user.

    The Technical Working Group’s first report is due March 15, 2011. Time is short, so don’t delay.

    Use these guidelines to take action. It is a call to action from Dr. Joe Paiva, veteran of surveying since the 1980s with whom many of you are familiar.

     

    Solar Activity

    As you’ve probably heard, we’re entering the next solar cycle, which is due to peak in May 2013.
    I want to periodically touch on this subject as the solar activity is going to increase over the next few years, and if the solar activity (geomagnetic storms, not sunspots) is severe enough, it will have an effect on GPS accuracy and tracking. Regardless of what you’ve heard in the mainstream media in recent months, the last event serious enough to affect GPS operations was in December 2006. That’s not to say that things aren’t heating up.
    But the recent activity does highlight the fact that “the Sun has become, somewhat suddenly, more eruptive,” according to Joe Kunches, of NOAA’s Space Weather Prediction Center. “We’ve been fortunate so far, in that the terrestrial effects — and impacts to GPS — have been very minimal. The most obvious sign of this has been the brilliant auroras up north.”
    “The video shows a large prominence eruption — billions of tons of plasma being strewn off the Sun. Some of it is drawn by gravity and rains back to the surface — the rest of it escapes. It’s the blown-away plasma that forms the coronal mass ejections that, when properly pointed, go by the Earth and cause problems for GPS,” said Kunches.
    Click on the following image to view a 15-second video of a solar flare that occured on February 24, 2011.
    Credit: NASA/GSFC/SDO

    From NASA:

    When a rather large-sized (M 3.6 class) flare occurred near the edge of the Sun, it blew out a gorgeous, waving mass of erupting plasma that swirled and twisted over a 90-minute period (Feb. 24, 2011). This event was captured in extreme ultraviolet light by NASA’s Solar Dynamics Observatory spacecraft . Some of the material blew out into space and other portions fell back to the surface. Because SDO images are super-HD, we can zoom in on the action and still see exquisite details. And using a cadence of a frame taken every 24 seconds, the sense of motion is, by all appearances, seamless. Sit back and enjoy the jaw-droppi
    ng solar show.

     

    March 17, 2011 Webinar: A Closer Look at L5: The Future of High-Precision GNSS

    Last year, the first GPS IIF satellite was launched. It became the first GPS satellite to broadcast the new L5 civilian signal/frequency. At 1176 MHz, it is further separated from L1 and L2 and located in the protected Aeronautical Radionavigation Services band, so there is no possibility of commercial interference like we see today with the LightSquared controversy. The availability of GPS L5 will usher in a new era of inexpensive, accurate GNSS receivers and will be the future of high-precision GNSS receivers, and quite possibly single-frequency receivers. I will also discuss the international support of L5 from other GNSS in development such as Galileo, Compass, QZSS, as well as SBAS (WAAS/EGNOS/MSAS).

    I’ll be presenting some interesting new material in the webinar such as graphics illustrating how many satellites (GPS and others) are projected to be broadcasting L1 and L5 just four years from now. It will be well worth 60 minutes of your time.

     

    Thanks, and see you next time.

    Follow me on Twitter at http://twitter.com/GPSGIS_Eric

     

  • Out in Front: Act Now to Protect GPS Signal

    This guest editorial addresses a subject of paramount importance to the GNSS industry, to the U.S. national infrastructure, and to the global GNSS community. I urge you to take immediate action by contacting U.S. government representatives, indicated at the end of this article.

    — Alan Cameron, editor-in-chief

     

    Guest Editorial by Joe Paiva

    GPS has become a key component of the U.S. national infrastructure, the driver of a significant part of the civilian economies of the world, and the enabler of millions of professional precision uses and consumer benefits.The viability of the GPS signal is now threatened — ironically by what appears to be a misguided attempt to increase accessibility to broadband by creating a needless zero-sum result for customers who want both services.

    The threat is real and immediate. The U.S. Federal Communications Commission (FCC) has issued a conditional waiver to LightSquared, a company engaged in developing 4G-LTE (long-term evolution) cellular networks for wholesale-only basis commerce with its business partners.

    LightSquared Scheme. LightSquared acquired a company providing a combined space-based and ancillary land-based service using the L-band radiofrequency. The FCC conditional waiver, granted to LightSquared on January 26 of this year, allows it to broadcast a new terrestrial broadband service from 1,500-watt terrestrial transmitters — 40,000 of which will eventually be installed by LightSquared — in the portion of L Band (1525 MHz–1559 MHz) immediately adjacent to the 1559–1610 MHz band used by GPS.

    Instead of offering dual-mode handsets exclusively as required by their FCC license, retailers purchasing this combined service can choose to offer terrestrial mobile phones only, which was the change in license terms that LightSquared was seeking via waiver. This change amounts to a de facto reallocation of Lightsquared’s spectrum use from space to terrestrial wireless. In fact, the new broadband service is planned to operate in urban areas, and the space service will operate outside these areas.

    The LightSquared terrestrial broadband signal is about 1 billion times the received power of the GPS signal on Earth. Members of the GPS industry have been conducting experiments and analyses, and these figures come from those very early studies. Soon, we may experience GPS interference — jamming — on an almost unimaginable scale and to a geographical extent that could create widespread havoc.

    Threats. The GPS system works so well that we often forget the complexity behind it and take for granted the service we use daily. One reason GPS works so well and is seldom defeated is that the signals broadcast by the satellites can be received under a wide variety of conditions on Earth. Historically, the FCC and the International Telecommunications Union, understanding potential interference issues, intentionally planned uses of adjacent swaths of the L-band so that satellite-based transmissions, relatively low-power, would be natural neighbors, so as to cause as little disturbance as possible to radio-navigation uses. This dedicated purposing of the bands and the resulting environment of negligible interference is one reason that GPS has become reliable and its use ubiquitous.

    Long-time observers of the GPS scene will remember how civilians, and especially potential international users, initially had uncertainty about the U.S. Department of Defense’s statements that the service would be free and not subject to any restrictions in one’s ability to receive and use the broadcast signals. This uncertainty was due primarily to the implementation of Selective Availability (SA), which intentionally degraded the available accuracy of the GPS signal. SA was permanently removed in 2000 by President Clinton’s 1996 Presidential Decision Directive.

    Many factors have enabled users and potential users to see GPS as a reliable, consistent technology that provides significant increases in productivity, efficiency, precision, continuing innovation, and many other benefits. These factors include the reliability of the overall GPS technology, improvements in receivers and in successive next-generation satellites, advances in differential and relative positioning, dynamic applications, and real-time kinematic solutions. And, just as importantly: stable, predictable U.S. policy.

    Investments. Now, by virtue of this unusual FCC action, uncertainty has been thrown into the viability of the hundreds of millions of GPS receivers in use today. Much research and development work is being done on improving receiver performance and taking advantage of improvements planned for the satellites. The most dollars go towards devising new applications, products, and services that improve the quality life of millions of Americans, create new companies, markets, and jobs. These dollars are also being spent by government agencies, not just the Department of Defense, but very visibly by Agriculture, Commerce, Interior, Energy, Homeland Security and Transportation. More than likely, the remaining departments either have active programs that are using or considering using GPS or are positively affected by others’ use of GPS.

    That’s just the executive branch. Other parts of the federal government, as well as state and local governments, do research on GPS technology and applications and actively use GPS to improve the lives of citizens, increasing work and recreation, efficiency, and safety. In many local government settings, there is active cooperation to improve delivery of services by having governmental and non-governmental organizations collaborate around the simple fact of accurate position being available through GPS, with significant cost savings in current lean budgets.

    It is inexplicable that another part of the government would be so cavalier in rapidly and uncharacteristically granting a waiver that clearly endangers the whole system. And only after granting the waiver, which must act at least as a yellow light for LightSquared’s mobilization plans, comes the requirement for a study — to be headed by LightSquared — to determine impacts and mitigation of interference with the GPS signals.

    Why Fast Track? The FCC grant of a reallocation of spectrum use from space to terrestrial on a fast-track waiver did not follow the standard FCC rule-making process for reallocation of spectrum use. The standard regulatory approach allows sufficient time for robust public comment by all potentially affected parties, including the conduct of interference studies and the introduction of comments on interference results in the public record. Instead, the FCC order granting the waiver to LightSquared has mandated what appears to be fast-track GPS interference research.

    Currently, the proposed LightSquared terrestrial broadband service does not have an installed user base. In contrast, the installed GPS user base represents a broad and diverse range of use representing hundreds of millions of users established over 30 years.

    The final Working Group report is due to the FCC on June 15, 2011. The FCC order requires the GPS community to participate “in good faith” in this study effort. In response, the U.S. GPS Industry Council and others are working on this interference study to protect GPS operations under these extraordinary regulatory conditions.

    A further problem created by the FCC conditional waiver is that LightSquared is able to move ahead with its infrastructure development, assuming that viable solutions to the jamming issue will be found. For many GPS users, theoretical fixes are not likely to prove viable.

    Negative Impacts. Preliminary research done by member companies of the USGIC already has been reported in GPS World. The research indicates that LightSquared’s 1,500-watt terrest
    rial transmitters will result in a signal 90 dB stronger than GPS over the coverage area; this amounts to signal strength 1 billion times stronger than GPS. There is more to the research, all done with GPS simulators and signal generators (see env-gpsworld-integration.kinsta.cloud/data for test results).

    Clearly the jamming level will vary with geography. We don’t yet know LightSquared’s broadcast-tower siting plan. But it is clear that if LightSquared is allowed to broadcast terrestrially on the mobile satellite system (MSS) band, dedicated until now to signals compatible with satellite transmissions, there is a substantial danger that millions of GPS receivers will be adversely affected.

    Some obvious impacts are loss of operational viability of businesses involved in aviation, surveying, agriculture, engineering and construction, vehicle navigation, mariners, transportation, public safety and homeland security, disaster management, utilities, mapping, and scientific research. Several of these involve safety-of-life issues, which are at risk of being jammed.

    Keep in mind that GPS was envisioned as a system for space and time. Its longest life as a useful contributor to society has been as a time standard. Countless networks, whether for computing, broadcasting, power generation — even, ironically, cell phones — are synchronized using the most precise signal practically available. Fixed GPS receiving stations for time reference may be able to be designed to withstand some interference from high-power broadcasting on adjacent frequencies, but nobody has tried so far.

    Any hypothetical fixes for GPS beg a more fundamental question: Why should Lightsquared, a new entrant with no existing business, be allowed to shift the burden of mitigating interference created by its operations to millions of consumers, government agencies, and businesses who have invested in GPS over the last 30 years?

    Keep in mind that other users of the MSS band will also be affected. Many commercial and governmental uses of the very band that LightSquared will occupy with its terrestrial transmitters may also be jeopardized.

    We must also remember that the FCC has its own agenda, to implement its National Broadband Plan. What is truly difficult to comprehend is that broadband and GPS will serve the same mobile user.

    Action Needed. Please act now.

    • Write to your representatives in Congress, and to your professional and trade associations.
    • If you are an expert on radio or spectrum or GPS or whatever else is pertinent, make your comments, do your research if possible, and publish your results with all due speed.
    • Petition the FCC to turn the yellow light to red, while other paths to achieving LightSquared’s and the FCC’s goals are investigated.
    • Do not forget the Administration: the National Telecommunications Information Administration (NTIA) represents the president and the Administration as official co-regulator with the FCC of the spectrum where GPS operates. In the recent FCC Order, NTIA must review the report on results of the FCC-mandated interference study.
    • Specifically, ask Congress to demand that the FCC include specific language to protect GPS use in the final FCC Order to LightSquared after the interference study is completed.
    • Ask the Secretary of Commerce and the White House Office of Science and Technology Policy (OSTP) to inform the NTIA Administrator to urge the FCC chairman to take this same action to protect GPS in the final FCC Order.
    • Contact the FCC chairman directly and urge this same action.
    • Finally, help develop user and beneficiary awareness of the grave danger being posed to GPS and make your elected and congressional representatives aware of the impact that interference with GPS would have on your work.

    The large-scale disruption of the GPS service mustn’t be on our hands due to inaction.

    Points of Contact

    Send messages to FCC chairman, commissioners, and NTIA:

    • Edward.Lazarus at fcc.gov (Chairman Genachowski’s office
    • John.Giusti at fcc.gov (Comm. Copps’ office)
    • Angela.Giancarlo at fcc.gov (Comm. McDowell’s office)
    • Louis.Peraertz at fcc.gov (Comm. Clyburn’s office)
    • Charles.Mathias at fcc.gov (Comm. Baker’s office)
    • lstrickling at ntia.doc.gov (asst. secretary for communications and information, NTIA)

    International readers may contact the U.S. State Department, clorere at state.gov. For further contacts, see env-gpsworld-integration.kinsta.cloud/actnow.

    Joseph Paiva is a consultant to the geomatics industry, with background in private engineering, surveying and mapping consulting, and as developer and general manager for two geomatics products corporations.

     

    High-Precision Users

    High-performance L1 receivers (sub-meter) have a wide-bandwidth RF front-end to improve performance, about 20 MHz, compared to a consumer receiver that typically has a front-end bandwidth of 2 MHz. GPS World contributing editor for survey and GIS Eric Gakstatter discusses this aspect of the issue in his recent e-mail newsletter column at env-gpsworld-integration.kinsta.cloud/l2high.

  • The System: FCC Asked to Authorize Potential Interferer

    In November, December, and January, a regulatory drama with high potential impact on the GPS signal and domestic U.S. GPS users began unfolding before the Federal Communications Commission (FCC). As this magazine goes to press on January 24, the issue remains far from resolved, although hearings and far-reaching decisions may have transpired by mid-February.

    A company called LightSquared applied to the FCC in late November for modification of its authority for ancillary terrestrial component (ATC). It asked the FCC to grant it permission to broadcast a co-primary terrestrial wireless service in the L-band frequencies typically reserved for space systems and radionavigation satellite services. Lightsquared wants to broadcast in those frequencies, not only from space but from powerful terrestrial transmitters that could effectively overload the GPS signal for millions of users in metropolitan areas across the United States. LightSquared asked the FCC to fast-track its request.

    The National Telecommunications and Information Administration (NTIA) has expressed its concern that LightSquared’s proposal to sell wholesale terrestrial-only services could interfere with navigation and E-911 systems. NTIA is concerned that terrestrial-based devices operating in the mobile satellite services band could interfere with GPS timing receivers, aeronautical communications, and the Inmarsat mobile satellite service used by the Department of Defense.

    Write to Congress. Members of the GPS community who are concerned by the proposal may contact their Congressional representatives, to advocate for a fully independent technical study by the NTIA before the FCC takes any action. Contact information and appropriate case file numbers are given at env-gpsworld-integration.kinsta.cloud/fcc.

    The FCC may have decided not to follow the Administrative Procedures Act, which directs it to consider a waiver request under an open and transparent rule-making, so that all affected parties may comment. It appears that the FCC could grant a waiver to LightSquared for a terrestrial wireless broadband service, but condition the service going operational on interference studies. Lightsquared has proposed that such studies be conducted under its own direction.

    Voices within the GPS community have asked for an independent, third-party, unbiased technical analysis to precede a fact-based rule-making, rather than a study organized and led by the interested party.

    LightSquared previously received authorization to build a hybrid network using satellite and terrestrial-based communications. The waiver would allow its wholesale customers to offer terrestrial-only services. The company’s buildout is scheduled to include a 40,000-cell-site terrestrial network deployed by Nokia Siemens Networks that will cover around 90 percent of the population of the United States.

    The trade publication RCR Wireless reported that Lightsquared may have run short of funds. “The company has raised about $2 billion to date. Reuters is reporting that Harbinger Capital Partners, which is funding LightSquared, has let some employees go as it attempts to right-size the company. The Harbinger fund now is valued at about $7 billion, a steep drop from the $26 billion it once counted.” The finding may shed light on why Lightsquared sought fast-track approval over winter holidays.

    24+3 GPS Configuration

    The U.S. Air Force 50th Space Wing announced completion of phase one of the two-phase GPS constellation expansion called Expandable 24, also known informally as 24+3, to increase global coverage and provide users with more robust satellite availability.
    Phase one concluded when the last of three satellites that began repositioning maneuvers in January, 2010, completed its journey on January 18. Phase two, a repositioning of three more satellites, started in August 2010 and is expected to end in June of this year. At that time, the GPS constellation will attain the most optimal geometry in its 42-year history, maximizing GPS coverage for all users.

    GPS IIF-2. The second satellite of the next generation, GPS IIF-2, received a launch date of June 23 from Cape Canaveral, Florida.

    EC: $1 Trillion in Europe Depends on GPS

    The European Commission (EC) presented its mid-term review on the development of Galileo and the European Geostationary Navigation Overlay Service (EGNOS). The report reiterates previous statements that Galileo will deliver initial services in 2014 — despite outside and unofficial speculation that the date may slip to 2015. The report also estimates that 6–7 percent of the gross domestic product (GDP) of developed countries in Europe, an amount that equals €800 billion ($1 trillion U.S.) depends on satellite navigation; that is, on GPS, for the time being.

    A December editorial in this magazine hypothesized that, on that basis, roughly $3 trillion of the global economy depends on GPS.

    Costs Rising. An EC message to the European Parliament and European Council served notice that reaching full operational capability for Galileo will cost €1.9 billion more than the €3.4 billion already allocated. The EC foresees an average annual expense of €800 million to operate Galileo and EGNOS.

    The administrative body for the European government issued one of its strongest statement yet as to the value of the satnav systems, however. “The ultimate objectives are not being called into question.” EC Vice President Antonio Tajani added, “We are satisfied with the progress made so far and committed to bringing this project to fruition.” The EC indicated its willingness to find alternative methods of financing the project.

    Check-up. Meanwhile, the first in-orbit validation (IOV) satellite goes through readiness testing at the European Space Agency’s technical center in the Netherlands. Four identical Galileo IOV satellites are in preparation, and the first to be completed has been selected for qualification testing, as the Protoflight Model (PFM). Satellite payloads were designed, developed, and assembled by EADS Astrium in Portsmouth, UK, with the overall satellite designed and developed by Astrium in Ottobrunn, Germany, and assembled by Thales Alenia Space in Rome, Italy.

    The PFM will endure simulated launch vibrations on an electrodynamic shaker, followed by sudden shocks simulating those during separation from the launch vehicle. Finally, it will take an acoustic battering matching the launcher’s sound pressure and frequency. The Galileo IOV satellites will be launched two at a time; a dispenser will hold them together within the launcher fairing and eventually release them in orbit. Pyrotechnic devices will shoot them safely away from the dispenser and each other.
    Once ESTEC testing is complete in February, the PFM will be reunited with the rest of the IOV quartet in Italy for a follow-up round of thermal vacuum testing, to prove that they can withstand the temperature extremes of space. Finally, the satellites will travel to Europe’s spaceport in Kourou, French Guiana in South America, to be launched on Russian Soyuz rockets.

    Pictured: Galileo protoflight model runs through its test paces at ESA.

    Michibiki Produces 3-Centimeter Accuracy

    According to a report in the Japanese business daily Nikkei, researchers in Japan conducted a test that yielded continuous 3-centimeter positioning accuracy for a car driving at 20 kilometers (approximately 12 miles) per hour, using a conventional GPS receiver equipped to receive corrections from the new QZSS satellite Michibiki. The authors imply that, unaided, the same equipment would have produced accuracy in the range of about 10 meters.

    The report also states that the Japan Aerospace Exporation Agency (JAXA) and Mitsubishi, who have partnered to develop and launch the Quasi-Zenith Satellite System (QZSS), have conducted further tests shown that the augmentation system maintains its accuracy with cars driving up to 80 kilometers (48 miles) per hour.

    QZSS’s current Michibiki satellite can cover Japan for eight hours a day; two additional satellites, planned for the future, will join it to provide continuous coverage and GPS corrections over mainland Japan and parts of Australia.

    As a commenter from the United States pointed out, “There’s nothing new about 3-centimeter GPS accuracy. The surveying, construction, and agriculture industries have been using 2–5 centimeter level real-time kinematic GPS technology for well over a decade. Post-processing can get GPS accuracy down to the millimeter level and measure tectonic plate movements. By the way, Michibiki (aka QZSS) does not work without GPS. The United States helped Japan build QZSS.”

    Nonetheless, if the tests used a conventional, consumer-grade GPS receiver, the results are indeed impressive. The availability that a full QZSS constellation will bring — the explicit goal of the project — in Japan’s skyscraper-dominated urban landscape should enable many heretofore impractical or impossible projects in car navigation, construction, tracking and monitoring, and location-based services.

     

    Shelton Space Commander

    Gen. William L. Shelton assumed command of Air Force Space Command (AFSPC) on January 5. Shelton replaces Gen. C. Robert Kehler, who will take over at the U.S. Strategic Command.

    Shelton has served in various assignments, including research and development testing, and space operations. As commander of AFSPC, he is responsible for organizing, equipping, training, and maintaining mission-ready space and cyberspace forces and capabilities for North American Aerospace Defense Command, U.S. Strategic Command, and other combatant commands around the world. Shelton also oversees Air Force network operations; manages a global network of satellite command and control, communications, missile warning and space launch facilities; and is responsible for space system development and acquisition. AFSPC is comprised of more than 46,000 professionals, assigned to 88 locations worldwide and deployed to an additional 35 global sites.

     

    Des Dorides for European GNSS Supervisory Agency

    Carlo des Dorides of Italy will head the European GNSS Agency, formerly known as the European GNSS Supervisory Authority (GSA). The Czech Republic’s Transport Ministry joined the European Commission (EC) in making the announcement. The GSA will gradually move its headquarters to Prague over the next two years.

    “The election of the Italian candidate is unambiguously good news for both the Czech Republic and Galileo itself,” said Karel Dobes, the Czech government envoy for the Galileo system. “His idea of the future shape of the agency rests in a stronger and greater agenda than nowadays, which would provide greater opportunity for our firms to get lucrative orders. It is a business with the highest value added, thanks to which local firms and the whole Czech Republic may get billions of crowns in the future.”

    Des Dorides was profiled by GPS World magazine as one of the 50 Leaders to Watch in GNSS in 2006. At that time he was head of the Concession Division of the Galileo Joint Undertaking, the GSA’s predecessor.

     

    GLONASS Goes for 
Ten-Year Plan

    The GLONASS plan for 2011–2020 is ready and now undergoing the final stages of approval, Sergey Revnivykh, Deputy Director General of the Central Research Institute of Machine Building of the Federal Space Agency, told a Russian business newspaper.

    “In March–April, the program will be presented to the government. I can say that the amount [of funding] is sufficient to meet the prospective demands of consumers and ensure parity with other navigation systems. During the program period, 2012-2020, GLONASS, in [terms of its] parameters will not yield to the planned development of the GPS and Galileo systems.”

    According to Revnivykh, by 2019 the GLONASS constellation will consist entirely of new-generation GLONASS-K satellites. In addition to existing FDMA signals, they will transmit CDMA signals in the format of CDMA (the same format as GPS and Galileo) and their service lifetime will increase to 10 years. Flight testing of a GLONASS-K prototype, originally scheduled for December 27, was postponed to a later date, to be determined in early February.

    Two prominent executives associated with GLONASS were dismissed, and the program came under increased scrutiny after a launch disaster drowned three new satelites in the Pacific Ocean.