Category: BeiDou

  • Expert Advice: The Tigers Claim Their Territory

    Expert Advice: The Tigers Claim Their Territory

    Tigers-CSNC2015

    Report from the 2015 China Satellite Navigation Conference

    By Greg Turetzky

    This May, the sixth China Satellite Navigation Conference (CSNC) was held in Xian, site of China’s famous buried warrior tombs. This was the fourth time I have attended, and every year the event has grown in both attendance numbers and global importance.

    The conference opened with the usual provider updates on satellite systems and international collaboration. There was nothing truly unexpected. All the providers continue to make progress towards launching new satellites with new capabilities, as well as providing regional augmentation systems for aircraft navigation.

    The hosts were their usual gracious selves and put on a very entertaining evening at “The Night of Beidou” event with wonderful food as well as music, dancing and and acrobats.

    Tigers-pullquote

    Exhibit Hall

    The show floor continues to grow at a rapid rate. The program listed122 exhibitors. The market has clearly entered the rapid proliferation stage. The booths were large, well-staffed and busy even during times when technical sessions were in progress. It was hard for me to determine what kind of business was being conducted as there were not many booth staff that spoke English. However, that seemed very appropriate as it was clear that the Chinese domestic market for BeiDou, or BDS, is well established and growing.

    In fact, many of the booths were regionally sponsored as there seems to be plenty of local subsidization to grow the GNSS industry in all areas of China. Many companies were displaying end-user products for all segments, from watches to phones to automotive to survey. I also noted significant growth in the number of chipset suppliers; I stopped counting at 10. Of further note and interest, the first few mergers/partnerships have taken place, as the market starts to make its natural turn from proliferation to consolidation.

    Technical Sessions

    The technical content of the conference is impressive. Approximately 280 papers were presented in up to nine simultaneous tracks over three days. Another 100+ posters were available for viewing.

    Here are titles of a few of the papers I liked:

    • Analysis of relative positioning performance of BDS triple frequency
    • Anti-spoofing design for Civil Navigation Signal system
    • Clock-error resolution strategy and precision analysis of GNSS real-time precise satellites
    • Research on detection and identification methods of satellite navigation RAIM multi-satellite failures.
    • Research on Wi-Fi/INS indoor pedestrian navigation system based on environmental feature augmentation
    • Reflections on demands of BDS intellectual property rights in satellite navigation industries
    • Review of anti-interference RF of satellite navigation receivers
    • A new TOA estimation method for the navigation pulse of X-ray Pulsare.

    If you plan to visit next year, you should consider bringing a translator. Many of the sessions have simultaneous translation, and most of the presentations have both English and Chinese slides, but not all of them. In the past, I have always enjoyed the policy and IP session, but this year it did not have a translator and the presenters spoke in Chinese, so I cannot give you much information. I did notice that several other U.S. companies had sent representatives who were native Chinese speakers.

    Conclusion

    The Chinese market is now full of grown tigers. I think they worry more about domestic competition for large domestic opportunities than they do about foreigners taking market share from them. That kind of competition has spurred them to catch up quickly in terms of technology and performance to where the big foreign competitors are. I foresee intense domestic competition in the short term leading to fewer, bigger, stronger players who will then be well positioned to compete in the global marketplace.


    GREG TURETZKY is a principal engineer at Intel responsible for strategic business development in Intel’s Wireless Communication Group focusing on location. He has more than 25 years of experience in the GNSS industry at JHU-APL, Stanford Telecom, Trimble, SiRF and CSR. He is a member of GPS World’s Editorial Advisory Board. See his previous reporting on the 2014 CSNC, “Tigers, Tycoons on View at China Satnav,” and the 2013 conference, “Little Tigers versus Wolves.”

    The statements, views, and opinions presented in this article are those of the author and are not endorsed by, nor do they necessarily reflect, the opinions of the authors present and/or former employers or any other organization the author may be associated with.

  • Will China Win the Automated Vehicle Race?

    Janice Partyka
    Janice Partyka

    By Janice Partyka

    The race for the automated vehicle is on. This time, it’s not about whether automotive OEMs or tech will own the vehicle. It’s a battle between Baidu, China’s web giant, and Google, and it isn’t clear who will win. Baidu has announced it will launch an unmanned car in the second half of this year. Despite speculation that Baidu will be working with BMW, Baidu hasn’t announced its automotive partner. The Baidu vehicle will provide the flexibility of some conventional controls, such as pedals, coupled with automation, unlike Google’s approach of being completely autonomous, without pedals and steering wheel.

    One of the most practical uses of artificial intelligence is in the automated vehicle, as cars need to recognize and sort images they “see,” and make quick safety decisions. In a recent TED talk, Chris Urmson of Google revealed a few of the unusual things that Google cars have had to process while driving. The cars have successfully encountered a woman in an electric wheelchair chasing a duck on the road and a child driving a toy car in the road. I wouldn’t be surprised if there are some even weirder encounters that Google is shielding us from.

    Artificial intelligence is critical to the automated vehicle. This year Baidu won a prestigious international artificial intelligence competition at Stanford, but was just stripped of its title and barred from competing in 2016. Apparently, the Baidu team broke the rules on how many tests they could run. In the competition, computers had to recognize and sort images and classify objects into 1,000 different categories. The teams were allowed to run a limited number of tests to train their programs on identifying objects. The Baidu team exceeded the limits by submitting their program using different accounts. In an article in the New York Times, Jitendra Malik, an expert in computer vision, compared the actions of the Baidu team to drug use during a sports competition. “If you run a 9.5-second 100-meter sprint, but you are on steroids, then how can your result be trusted?” Malik said.

    Automated vehicles aren’t the only location market Baidu is aggressively pursuing. With technology from IndoorAtlas, Baidu has rolled out indoor location to 270 million active users of its map application. The solution uses mobile device technology to create geomagnetic maps of indoor places to enable indoor search and to power store and product search, as well as way-finding. A physical map of a building is uploaded into an app on a mobile device, like a smartphone. Using the app, a person walks all corridors in a building, thereby adding location positioning and creating a map.

    Let’s return to the topic of automated vehicles. Earlier this month, Uber suffered a blow when the California Labor Commissioner’s Office ruled that drivers are employees and not contractors, and therefore need to be so compensated. Taxi and limo services had been hurt by services like Uber, and they pressed for redress from what they felt was unfair competition.

    Like Uber, the automated vehicle market will likely hit intense push-back from a number of industries that will be disrupted. These include insurers, taxi and truck drivers, and personal injury and traffic litigation attorneys. These groups may try to build regulatory roadblocks for automated vehicles. And as their businesses may suffer, the automated vehicle industry needs to think now about how to mitigate the damage and create allies. With a completely different political process, Baidu may encounter no such resistance in China — quite an advantage. Perhaps Baidu will be first out of the gate, but may not be the long-term winner. Think Ford Sync.

     

  • Singapore Joins with China to Develop Apps, Protect BeiDou Signals

    Singapore and China are jointly opening a center to develop applications for the BeiDou GNSS, according to a report in Space News. The nations also have signed a commercial agreement to create anti-jamming systems to protect BeiDou signals.

    At a briefing during the CommunicAsia show held in Singapore May 31-June 2, SpaceTime Technology Pte Ltd. and ST Electronics (Satcom & Sensor Systems) Pte Ltd. signed a memorandum of understanding to “develop in Singapore an interference-resistant Beidou satellite positioning system,” SpaceNews report.

    The companies said the goal is to protect BeiDou signals from unintentional jamming in urban environments, where wireless devices occasionally overstep their radio-frequency boundaries.

  • LabSat’s SatGen v3 Adds BeiDou to Simulator Scenarios

    LabSat’s SatGen v3 Adds BeiDou to Simulator Scenarios

    Photo: LabstatSatGen v3 software is now available for the LabSat GNSS simulator by Racelogic. Version 3 includes BeiDou (BDS) in addition to GPS and GLONASS.

    SatGen is billed as a powerful and intuitive software package that gives users the ability to create scenarios for replay through any LabSat simulator. The software creates either user-generated or imported trajectory files for use with a LabSat simulator.

    The addition of the BeiDou B1 signals means that users can now test a device’s effectiveness as if it were being used within the operating area of the Chinese constellation, which at present only provides full coverage in Asia.

    The BeiDou constellation is set to become globally operational by 2020. With the new SatGen v3, users can create scenarios that include signals from satellites yet to be launched, so new products can be developed in readiness for the full constellation.

    SatGen v3 can produce scenarios with one, two or three sets of signals being simultaneously output: GPS, GLONASS and now BeiDou. The software now matches the record and replay abilities of the LabSat 3 simulator.

    A trial of SatGen is available here. To purchase a full copy contact a LabSat distributor.

    The LabSat 3 GNSS simulator.
    The LabSat 3 GNSS simulator.
  • The System: All Systems Go, with a Spring into Space

    Planet Earth gained five new navigation satellites in late March, for four satellite systems.

    GPS. The U.S. Air Force’s ninth GPS Block IIF satellite (GPS IIF-9) launched on March 25 from Cape Canaveral, Fla. The IIF-9 rode aboard a Delta IV rocket, the workhorse of the GPS fleet for successful launches. The satellite was declared operational on April 21.

    “Many thought the Delta IV and GPS days were long gone, but the recent questions concerning reliable and proven launch vehicles have brought them back online, so to speak,” said GPS World Defense Editor Don Jewell. “The 20-year milestone for GPS space vehicles on orbit that occurred on April 27 translates to approximately 500 orbital years just for the IIR and IIF constellations alone. The IIAs may account for that many orbital hours as well.

    “This is by far the most successful launch record ever put together by any nation or government. No other space-faring nation even comes close. The U.S. Air Force and all the players should be proud of all these records and more, plus we have one more GPS asset on orbit, providing GPS signals to the world and all they enable, courtesy of the USAF.”

    Galileo. Two days later, March 27, a duo of Galileo satellites was successfully launched from Europe’s Spaceport in French Guiana. The seventh and eighth Galileo satellites rode aboard a Soyuz ST-B rocket. Both are in their planned orbits.

    IRNSS. The next day, March 28, the fourth satellite (IRNSS-1D) of  the IRNSS satellite navigation constellation was launched onboard PSLV-C27, and reached its orbital slot April 9. The Polar Satellite Launch Vehicle blasted off from the Satish Dhawan Space Center on India’s east coast, in the 28th consecutive successful PSLV mission.

    BeiDou. On March 30, China launched the first of a new generation of navigation satellites, BeiDou-3 M1, for its BeiDou constellation. BeiDou-3 M1 is the first of 17 next-generation Beidou navigation satellites. It will have a new navigation signal system with inter-satellite links and other tests to verify the satellite navigation system. The new series of satellites is expected to mark an advancement in the completion of Beidou Phase III several years ahead of schedule, by as soon as 2017 rather than 2020.

    GLONASS. Not making the March launch cut, GLONASS kept its hat in the orbit ring, so to speak, by issuing some far-sighted predictions. Nicholas Testoyedov, CEO of Information Satellite Systems Reshetnev, said that the first GLONASS-K2 spacecraft will be launched into orbit in 2018. “New code division (CDMA) signals will be emitted, so it will provide more accurate positioning for users.”

    The GLONASS budget for 2015 will be cut by more than 5 billion rubles, a drop of more than 10 percent. GLONASS is also suffering through an embezzlement scandal, related to construction of a new ground control center.

    Galileo's worldwide ground segment as of March 2013.
    Galileo’s worldwide ground segment as of March 2013.

    Galileo Ground Upgrade

    On April 9, the European Space Agency announced completion of a full-scale hardware and software migration to version V2.0 of its global Ground Mission Segment providing all Galileo navigation messages. The Ground Mission Segment was turned off Jan. 26, allowing the migration to take place over the month of February. March was taken up with detailed checking by operations and system, concluding in a final check on March 31 to validate the successful migration.

    “The upgrade has provided better overall performance and availability, along with improved robustness, security and operability,” explained Martin Hollreiser, overseeing mission segment development for ESA, with Thales Alenia Space France as prime contractor. “An overall 25 percent performance improvement is confirmed.

    “Three new sensor stations, Kiruna, Ascension and Azores — used to monitor the satellite navigation signals — were added to the operations chain, as well as a new uplink station in Papeete, to uplink corrections incorporated in the navigation message to the satellites for broadcast to the users.”

    The Ground Mission Segment at its core is determining the exact satellite orbits and synchronizing all the satellite and terrestrial elements of that clock: the relevant control center is linked to a global network of ground stations (sensor and uplink stations). The Galileo signals currently undergo technical testing, with early services for the public projected for 2016. “A further update is foreseen for the end of this year,” Hollreiser added, although this will occur with no interruption of services.

    GPS Glitch Dates from 2011

    On April 15, the U.S. Air Force GPS Directorate said data analysis shows that a technical error affecting some GPS IIF satellites first appeared in 2011. The error affects the way the ground control system builds and uploads messages transmitted by the satellites, but does not affect the accuracy of GPS signals. It involves the ground-based software used to index messages. “A GPS message indexing issue was recently identified that affects a limited number of active GPS IIF satellites, but does not degrade the accuracy of the GPS signal received by users around the globe. The result is an occasional broadcast not in accordance with U.S. technical specifications. ”

  • ComNav, CGEOS Build First BeiDou CORS Station in Europe

    Experiencing the Qiao Station with ComNav T300 for surveying.
    Experiencing the Qiao Station with ComNav T300 for surveying.

    Europe’s first commercial BeiDou CORS station  — Qiao CORS Station — has been built in Wallonia, Belgium. ComNav partnered with local company CGEOS – Creative Geosensing on the project. ComNav develops and manufactures GNSS OEM boards and receivers for demanding high-precision positioning applications.

    Qiao means bridge in Chinese, and Joël van Cranenbroeck, managing director of CGEOS, is working to build the bridge between the Chinese and European GNSS industries by introducing the Chinese high-precision GNSS technologies of ComNav Technology to European users, ComNav said in a statement.

    The Qiao Station can track BeiDou Navigation Satellite System on the three frequencies and transmit observation data in RTCM format in real time through NTRIP and observation data in RINEX format. It enhances the positioning performance and result by combining BeiDou with GPS and GLONASS.

    Currently, the BeiDou Navigation Satellite System mainly covers  the Asia Pacific region. Though China is still in the process of building it into a global network, up to six BeiDou satellites can now be tracked in Europe during certain periods of the day. With the new Qiao Station, European users can now try the BeiDou system.

  • The System: Celebrating 20 Years of GPS

    The System: Celebrating 20 Years of GPS

    April marks the 20th anniversary of GPS FOC. U.S. Air Force Space Command declared Full Operational Capability (FOC) for the GPS constellation April 27, 1995, signifying the system met all requirements with 24 operational Block II/IIA satellites in their assigned orbital slots and providing both the military Precise Positioning Service (PPS) performance standard and the civil Standard Positioning Service (SPS) performance standard.

    FOC was formally announced on July 17, 1995.

    GPS IIF-9 Launch on March 25

    GPSIIF-launch-ULA-8As this magazine went to press on March 19, the U.S. Air Force’s ninth GPS Block IIF satellite (GPS IIF-9) was being readied for a March 25 launch [since successfully launched]. The satellite was encapsulated in the Delta IV rocket’s 4-meter-diameter nose cone at a processing facility, and moved to the launch pad at Space Launch Complex 37 for mating to its booster inside the mobile service tower.

    Launch is scheduled for March 25 at 2:36 p.m. U.S. Eastern time from Space Launch Complex 37 at Cape Canaveral Air Force Station, Fla. GPS IIF-9 marks the 29th Delta IV launch and the 57th operational GPS satellite to launch on a ULA or heritage launch vehicle.

    CNAV Performance Compares Favorably to Legacy Signals

    A March 5 announcement concerning the new L2C and L5 GPS civil signals states: “CNAV Message Types 10, 11, 30 and 33 are currently transmitted on seven GPS IIR-M (L2C) and eight GPS IIF satellites (L2C and L5). A Modernized Navigation (MODNAV) Tool integrated with the GPS ground control software (Architecture Evolution Plan or AEP) is generating the CNAV data messages. Daily CNAV uploads began December 31, 2014, and the U.S. Air Force reports that signal performance of CNAV matches or slightly outperforms Legacy performance: average user range error (RMS URE) from 25 February – 3 March 2015 was 0.50 m for Legacy and 0.57 m for Modernized; best week for Modernized signals since the broadcast initiated April 2014 was 0.42 m for 6 – 13 January 2015.

    “Users are reminded that these CNAV signals are ‘pre-operational’ and should be used with discretion until they become fully operational; the L5 message is currently set unhealthy,” concluded Rick Hamilton, CGSIC Executive Secretariat, USCG Navigation Center, in a status email to the Civil Global Positioning System Service Interface Committee (CGSIC).

    Galileo Six, Seven, Eight: Lay Them Straight

    The original (in red) and corrected (in blue) orbits of the fifth and sixth Galileo satellites, along with that of the first four satellites (green).
    The original (in red) and corrected (in blue) orbits of the fifth and sixth Galileo satellites, along with that of the first four satellites (green).

    On March 17, some stations participating in the International GNSS Service Multi-GNSS Experiment acquired E1 and E5a signals from Galileo 6 (FOC-FM2, GSAT0202). The satellite is using pseudorandom noise code E14.

    This development follows the successful repositioning of the sixth Galileo satellite into a corrected orbit, which will now allow detailed testing to assess the performance of its navigation payload. A 20-meter-diameter antenna at the European Space Agency’s (ESA’s) Redu center in Belgium will study the strength and shape of the navigation signals at high resolution.

    Launched with the fifth Galileo last August, its initial elongated orbit saw it traveling as high as 25,900 kilometers above Earth and down to a low point of 13,713 kilometers — confusing the Earth sensor used to point its navigation antennas at the ground.

    A recovery plan was devised between ESA’s Galileo team, flight dynamics specialists at ESA’s ESOC operations centre and France’s CNES space agency, as well as satellite operator SpaceOpal and manufacturer OHB. This involved gradually raising the lowest point of the satellites’ orbits more than 3,500 km while also making them more circular.

    The fifth Galileo entered its corrected orbit at the end of November 2014. Both its navigation and search-and-rescue payloads were switched on the following month to begin testing. Now the sixth satellite has reached the same orbit.

    This latest salvage operation began in mid-January and concluded six weeks later, with 14 maneuvers performed in total. Its corrected position is effectively a mirror image of the fifth satellite’s, placing the pair on opposite sides of the planet. The exposure of the two to the harmful Van Allen Belt radiation has been greatly reduced, helping to ensure future reliability.

    The corrected orbit means they will overfly the same location on the ground every 20 days. This compares with a standard Galileo repeat pattern of every 10 days, helping to synchronize their ground tracks with the rest of the constellation.

    “I am very proud of what our teams at ESA and industry have achieved,” said Marco Falcone, head of the Galileo system office. “Our intention was to recover this mission from the very early days after the wrong orbit injection. This is what we are made for at ESA.”

    The decision whether to use the two satellites for navigation and search-and-rescue purposes will be ultimately made by the European Commission, as the system owner, based on the in-orbit test results and the system’s ability to provide navigation data from the improved orbits.

    March 27 Launch Date for Galileo Seven, Eight

    The seventh and eighth Galileo satellites, set for launch together on March 27, were placed onto the Fregat upper stage of their Soyuz ST-B launcher in mid-March. [The satellites have been successfully launched.]

    The Fregat stage will hold the satellites in place during their four-hour flight into orbit 22,300 kilometers above the Earth. Then, at the correct altitude, the two satellites are sprung away in opposing directions.

    The Fregat upper stage was blamed for the  August mis-delivery of Galileo satellites five and six. The root cause of the anomaly producing the wrong orbits was a shortcoming in the system thermal analysis performed during stage design, according to findings by an independent inquiry board.

    The anomaly occurred during the flight of the launcher’s fourth stage, Fregat. It occurred about 35 minutes after liftoff, and was due to a temporary interruption of the joint hydrazine propellant supply to the Fregat thrusters. The interruption in the flow was caused by freezing of the hydrazine, resulting from the proximity of hydrazine and cold helium feed lines, these lines being connected by the same support structure, which acted as a thermal bridge. Ambiguities in the design documents allowed the installation of this type of thermal bridge between the two lines.

    IRNSS Launch Scheduled for March 29

    The launch of the fourth satellite for the Indian Regional Navigation Satellite System, previously scheduled for March 9, was postponed until March 29 at 13:00 UTC, due to the replacement of a faulty telemetry transmitter on the satellite. [The satellite has been successfully launched.]

    IRNSS-1D will be fourth in the seven-spacecraft IRNSS constellation.

    BeiDou, Too, in Late March

    There are indications that the first satellite in the BeiDou Phase 3 expansion may be launched by the end of March [since successfully launched]. Apparently, a BeiDou satellite has been shipped to the Xichang launch site, and tracking ships have left port for the open ocean. Also, a philatelic first day cover for the launch (a common Chinese practice) has been issued with a March 2015 inscription. This is likely a launch of a medium Earth orbit (MEO)satellite.

    Where It All Began for Galileo and EGNOS

    The European Space Agency issued a press information notice on June 11, 1995 — in the same timeframe as the GPS FOC announcement noted on the previous page — titled “Europe’s Contribution to a Navigation Satellite System.”

    “The European Commission, the European Space Agency (ESA), and the civil aviation organisation EUROCONTROL have agreed to cooperate on a joint programme).  The European Satellite Navigation (ESN) Action Programme, elements of which are GNSS-1 [First Generation Global Navigation Satellite System] and GNSS-2, is planned to run for five years (from mid-1995 to mid-2000) with a budget of the order of 150 million euros.

    National aviation authorities and the parties involved in the action programme see Europe’s commitment to satellite navigation as being of strategic significance for the future.

    “The main objective of the programme is to develop technologies that will ensure that data from the two existing Global Navigation Satellite Systems — the United States’ GPS and Russia’s GLONASS — which are both under military control, will also be available for civil use on a reliable basis and will provide the requisite precision.  In parallel, studies will be conducted in order to make preparations for a second generation satellite-navigation and positioning system (GNSS-2), to be deployed as from 2005.

    “In the first phase (GNSS-1), ESA’s contribution to the joint action programme will be EGNOS [European Geostationary Navigation Overlay Service].  Satellites stationed in geostationary orbit at an altitude of about 36,000 km will relay to aircraft, shipping or road vehicles information that will enable the recipients to determine their actual positions with greater precision than is possible by using GPS/GLONASS data alone.  Civil users of those systems receive artificially degraded data deviating by about 100 metres.  EGNOS, will enable in particular, to increase the number of satellites that can be seen by a given user within the geostationary broadcast area.

    “Around the period 2005–2008, after completing a trial period, the new system is due to be used as sole means.” 

    Galileo, Previously GNSS-2

    “It is planned to develop GNSS-2 in the period between 2005 and 2020, building on experience acquired under GNSS-1.  From the technical viewpoint, the second generation will be a considerable improvement on the first in terms of reliability, precision and availability. 

    “However, if Europe were to confine itself to developing the relevant technologies, its industry would have only a very slim chance of being involved in the construction of the satellites for the system or in the control and user segments for a second-generation civil system (GNSS-2). Given that U.S. and Russian firms are the current leaders in this area, it is necessary for strategic reasons for Europe to carry out a comprehensive development and demonstration programme as it must be able to prove it has the requisite capabilities before GNSS-2 becomes operational, which, in the experts’ opinion, will be from 2005.

    “The time schedule foreseen for the different steps can be summarised as follows:

    • GNSS-1 mission analysis and definition studies: mid-1995 to mid-1996
    • European GNSS-1 pre-operational mission (task 1): to end 1997. Development of the geostationary network, following the Inmarsat III launch and first ranging demonstration phase
    • GNSS-1 (task 2): 1996 to end 1998. In parallel to the development of the network, the Ground Integrity Channel will be set up, followed by a second demonstration phase
    • GNSS-1 (task 3): 1997 to early 2000. Wide Area Differential service for precision approaches to be set up and tested
    • Introduction of GNSS-1 as sole means: 2000/2003.”

    GPS World is indebted to Richard Langley’s CANSPACE archive of historical documents for this note of interest.

  • All GNSS Attend, But Galileo Gets the Spotlight

    Tim Reynolds
    Tim Reynolds

    First and foremost, let’s give a big hand to Adam and Anastasia, the two Galileo FOC satellites that were successfully launched on March 27. Following the not-so-successful Galileo launch in August, it was imperative that this go smoothly.

    Although the Double-A launch occurred after the conclusion of this year’s Munich Satellite Navigation Summit, anticipation of the event set the context for the entire convocation. The summit is a fixture on the European and global GNSS calendar. It is always intense, often spectacular and sometimes leaves one with contradictory feelings. This year it took place March 24-26 and sought to determine the future of PNT, encouraging delegates to look into the crystal ball and predict developments.

    If we go by the number of times these words were repeated during the three days of the summit, the future will hinge around compatibility and interoperability. The multi-constellation GNSS is already here. The elephant in the room remains, as always, interference, but here integration of alternative sensors and signals should hold the key to continuous and possibly resilient operations.

    As usual the summit kicked off with a high-level plenary in the imposing Allerheiligen-Hofkirche (Court Church of All Saints) in the Residenz München, the Bavarian royal palace. The welcoming speeches and presentations were interspersed with some pleasant jazz, and the atmosphere was relaxed.

    Into the Crystal Ball

    Matthias Petschke, director of EU Satellite Navigation Programmes at the European Commission, admitted that 2014 had been difficult, but he was looking forward to 2015. Clearly the deployment of the Galileo infrastructure — especially the space segment — was critical, and the March 27 launch was very much on his mind. However, he expressed confidence that the launch would be fine and that satellite production was, and would remain, on schedule. In the long view, he stated: “We will make it for 2020,” signifying full operational capability (FOC).

    He also talked about stimulating global markets to foster uptake of Galileo and EGNOS, and this was discussed by Carlo des Dorides, executive director of the European GNSS Agency (GSA). The ground infrastructure is very much in place and preparing for the Galileo exploitation phase. A significant milestone in that process would be finding the right partner to lead Galileo operations for the next ten years. A tender was now in process to find that organization or consortium. Des Dorides described the process as a competitive dialogue with the emphasis on finding a partner who can inspire new ideas and provide innovative solutions. The contract is big, worth around 1 billion euros.

    Carlo des Dorides, Executive Director of the European GNSS Agency (GSA), discusses the 1 billion euro tender, now in process to find the organization or consortium to lead Galileo operations for the next ten years. Photo: GSA
    Carlo des Dorides, Executive Director of the European GNSS Agency (GSA), discusses the 1 billion euro tender, now in process to find the organization or consortium to lead Galileo operations for the next ten years. Photo: GSA

    He also emphasized the successes for EGNOS in the year. Almost 180 airports now benefit from EGNOS-enabled approaches and more than 70 percent of “GNSS-enabled” farmers in EU use the EU’s SBAS.

    Johann-Dietrich Wörner, chairman of the German Aerospace Centre (DLR) — and the nominated next Director-General of ESA – highlighted the growing dependence of critical services on GNSS. In this context multiple systems were not a question of competition; it was all about redundancy and safety. Multi-GNSS improves availability, accuracy and reliability.

    The view from the United States was given by Harold “Stormy” Martin, Director, National Coordination Office for Space-Based Positioning, Navigation, and Timing in Washington, D.C. The GPS fleet was now 30 strong in orbit including four successful launches in 2014 and he stated the 2014 averaged user range error to be 70 cms — the best ever — and improving year on year.

    One major upcoming trend is a realization that there’s a need to establish a U.S.-wide backup coverage for GPS outage due to natural or man-made interference. The U.S. is currently assessing alternatives with a decision likely in summer 2015.

    There was a particularly warm welcome from the audience for Michael Khailov, deputy head of Roscosmos and co-ordinator for GLONASS. Last year the Russians were conspicuous by their absence at the Munich Summit, but for 2015, despite the intervening local difficulty in Ukraine, they were back in force. Khailov claimed that the sustainable development of the world depends on GNSS. On more esoteric ground he stated that GLONASS had maintained stable operations in 2014 and three more satellites had bene launched. Further launches would depend on operational circumstances. The user domains for GLONASS were continuously expanding. Continuing the summit text he said that it was better [working] together than separately — in fact separately often doesn’t work at all and therefore we must continue to promote interoperability and the Munich Satellite Summit is a good forum for this.

    Jianyun Chen of the China Satellite Navigation bureau also took up the theme of all GNSS together. Sixteen Beidou (pronounced — for the avoidance of doubt — as ‘bay-doe’) had been launched since 2007 and the Chinese had been in discussion with Russia to ensure full interoperability with GLONASS. This process will be repeated with GPS and Galileo.

    GNSS Updates

    One of the idiosyncrasies of the Munich Summit is its very discreet signage. If you don’t know where it is — and specifically the correct side door that brings you up two floors to the main Max Joseph Saal venue — it is highly likely you’ll miss it! But once you are in it is two full-on days of updates on systems and discussions on a vast range of topics that impinge on the development and implementation of GNSS around the world.

    Discreet signage. Photo: GSA
    Discreet signage. Photo: GSA

    The first two session of the summit proper gave updates on the GNSS systems in operation and under development as well as the regional and augmentation systems. Much of the material was slightly more detailed versions of presentations at the plenary but a few news snippet emerged.

    “Stormy” Martin said that a modified battery charge control had been implemented that would extend operational life for some of the fleet by one or two years. He also reiterated the improving accuracy performance of GPS which was now much better that its published standards. He predicted that the first GPS III would be available for launch in 2016 and said that GPS was improving every day.

    Eric Chatre from the European Commission reiterated that Galileo was still expecting to start early services in 2016 with full operational capability in 2020. He expected 18 satellites to be launched by 2018. The new Ariane 5 launcher will enable the launch of four satellites at one time and the first launch with this system would be in 2016. In terms of the ground segment only one station in the Pacific was yet to be established.

    Sergey Karutin of Roscosmos talked about a four-fold accuracy improvement for GLONASS with the use of new clocks and the introduction of new CDMA signals that will improve accuracy and access. According to Dongfeng Yu of the China Satellite Navigation Office the BeiDou constellation is moving from “regional to global, active to passive” and is aiming for global coverage by 2020.

    U.S. SBAS developments were covered by Deborah Lawrence of the Federal Aviation Administration (FAA). The Wide Area Augmentation System (WAAS) now has 100 percent coverage for LPV200 in CONUS. More than 41,000 runway ends are now included, and she predicted full completion in 2016.

    Jean-Marc Pieplu of the GSA talked about EGNOS status. The next system release (2.4.1) should be published in Q3 2015 and will include a significant input on ionospheric corrections. Further service evolution includes a plan to declare LPV 200 in Q4 this year and EGNOS coverage will be extended to 72 deg North and ensure full coverage of the 28 EU member states.

    The Russian Augmentation system SDCM performs at 0.8 metre accuracy according to Grigory Stupak of JSC / Russian Space Systems. He noted new validated SDCM ground stations had been established in Antarctica and Brazil and stated that global exploitation was a key objective for SDCM as its satellite coverage was very wide. GLONASS and GPS together could ensure complete coverage. He also indicated that work was in hand for SDCM SBAS service certification for LPV 200 and he called for providers of all WAAS to work closely together.

    2020 Vision

    After lunch we were offered the chance to hear some expert views on the future of GNSS and PNT with Prof Vidal Ashkenazi of Nottingham Scientific Limited asking for their vision of GNSS in 2020. By that year there should be 100-120 GNSS satellites in orbit, multi-constellation receivers would be the norm, but what would be the new applications and what were the challenges?

    Jamming and spoofing would still be issues. Pierre Bouniol of Thales thought that in civil aircraft receivers would probably incorporate jamming indicators by 2020 to inform users when signals may be compromised. For Stuart Riley of Trimble the key was integration of other sensor signals to bridge any GNSS signal outage. Gang Mao of Unicore Communications Inc. in China considered multiple frequencies to be a big help in reducing the threat of jamming. Nigel Davies of QinetiQ agreed saying there were a host of technical solutions but key for success would be solutions that use low power, are low cost and feature high usability. He also noted that safety certification of receivers for use in driverless vehicles would be required and this challenging application would need the provision of robust continuous navigation — and sub-metre accuracy.

    The future market for GNSS was also discussed in a session that unveiled the GSA’s 4th Issue of its comprehensive GNSS Market Report. With almost four billion GNSS devices used worldwide and all regions experiencing growth, GNSS represents an unprecedented business opportunity. Over the past 15 months the GSA’s team of market monitoring experts has taken a close look at all aspects of the GNSS marketplace with analysis of both hardware and software market opportunities, technology trends and future developments.

    Gian-Gherardo Calini, Head of Market Development at GSA, gives highlights of the comprehensive GNSS Global Market report. He will deliver this information in an April 16 webinar hosted by GPS World. Photo: GSA
    Gian-Gherardo Calini, Head of Market Development at GSA, gives highlights of the comprehensive GNSS Global Market report. He will deliver this information in an April 16 webinar hosted by GPS World. Photo: GSA

    The top-line results were presented by Gian-Gherardo Calini, Head of Market Development at GSA. GNSS is one of the few growing markets in the world showing 12.7 percent CAGR. It is a very attractive market with volumes and revenues driven by mass market segments: the dominant two being Location-based services and transport applications. This latest edition includes information a new market segment: Timing and Synchronisation. One area that is not included is security and government applications. Mr Calini indicated that this information has been collected by the GSA team but as it is essentially for users of the Public Restricted Service (PRS) it was not included in the open report.

    Although the report is very much “Galileo flavored,” its findings are of great importance and value to whole GNSS community and will be the subject of a GPS World webinar with Mr Calini and myself on 16 April. You can register — free — for this informative global perspective now.

    A panel discussion followed and covered a range of topics and applications from aviation to agriculture. Again the consensus was that chips would become multi-constellation and quickly. Philippe Prats of STMicroelectronic outlined automotive applications from insurance applications to advanced driver assistance systems (ADAS).

    The role of government mandates in establishing markets was seen as positive. The e911 mandate in the states had provided the seed for GPS integration into smartphones. Similarly authentication was also seem as a significant future market driver.

    Multi frequency was also showing on industry’s radar and in a couple of years will be a reality thought Philippe Prats with the main motivation being better accuracy. Frank van Diggelen of Broadcom highlighted the recent GPS World feature demonstrating cm accuracy on a smartphone.

    Legal Issues

    A dedicated session on legal issues was not the best attended part of the conference, which is a shame as it had some serious points to raise and highlighted a gap that is opening up between our technical abilities in GNSS and the legal basis for its use. The Munich Summit is to be commended for its commitment to providing a platform for these issues every year; they are often ignored elsewhere.

    Oliver Heinrichs, a partner at BHO Legal in Cologne, emphasised the need to establish a firm regulatory framework and to ensure that any decisions did not cross World Trade Organisation (WTO) provisions and the General Agreement on Tariffs and Trade (GATT). In particular the idea of mandating a specific GNSS for applications such as emergency response systems in cars may well be incompatible with WTO rules.

    Amedeo Arena of Universitá degli Studi di Napoli Federico II in Naples noted that all GNSS players were members of the WTO and considered that GNSS services and their trade was definitely “caught by the GATTs” so no favouritism for ‘home’ systems should be allowed.

    Another area of controversy is automated vehicles. In discussion after the session I learnt that current international conventions governing the use of motorised vehicles require a human supervisory role at all times. There will need to be some fundamental legal groundwork done before the first driverless vehicles will be allowed out on the road for real.

    These are legally complex issues and certainty will only come from test cases. Talking of complexity Aleksey Bolkunov of the Russian Federal Space Agency revealed that the legal, regulatory and standardisation measures governing GLONASS and GNSS in Russia consisted of more than 900 documents originating at various different levels of the state. This clearly gave great scope for “regulatory collisions” and he is involved in work to develop a single regulatory framework that should eliminate the remaining barriers to GNSS use in Russia.

    Emerging Applications

    Peter Grognard of Galileo Services chaired a final session of the day on emerging applications. Bruno Bougard of Septentrio saw dependable accuracy as key to emerging markets. He thought high precision driven by surveying was becoming more and more mainstream. For autonomous driving the challenge was to provide cost-effective, dependable accuracy at 10-30cm that was safe, reliable, and always available. This would require multi GNSS, multiple signals, highly integrated sensors and transparent and open augmentation.

    For Neil Gerein of Novatel the mantra is “Accuracy, availability, assurance.” Users needed availability to their PNT solutions at all times. He also saw future applications integrating GNSS with inertial sensors and correction systems for high accuracy without the need for a base station.

    or Neil Gerein of Novatel the mantra is “Accuracy, availability, assurance." Photo: GSA
    or Neil Gerein of Novatel the mantra is “Accuracy, availability, assurance.” Photo: GSA

    Lionel Garin of Qualcomm Inc talked about ADAS. Safety was paramount and he foresaw the need for rigorous design and certification procedures similar to that required for the aviation market. Fortunately the industry has lots of expertise here. Philip Mattos of u-blox UK argued that a volume market is in femtocell and small cell synchronisation in mobile networks where GNSS is the lowest cost solution.

    Tom Stansell praised geometry as the most important and unique ingredient supplied by multi constellation GNSS. And the second most important ingredient was interoperability. He doubted users would care where their signals originated and devices would still be generically described as ‘GPS’ into the future. Application growth will be stimulated by the better geometry supplied by multi-GNSS constellations. When the E6 signal became available he predicted that 10cm accuracy would enable reliable lane keeping for ADAS.

    And Galileo will supply E6 for free said Ignacio Fernandez Hernandez from the European Commission. Ignacio works on the Galileo Commercial Service design and outlined some significant differentiators of the European system including its broad signal for high accuracy and better multipath resilience, more stable clocks and improved ionospheric modelling compared to GPS.

    Lionel Garin sounded a note of caution at the end of the session when he noted that multi constellation ability was good, but he was not sure what was actually gained beyond two, or perhaps three, constellations.

    GNSS for Weather

    The final day of the conference saw a few fragile heads courtesy of the previous evening’s Summit Space Night 2015 sponsored by Airbus Defence & Space, which took place at the Filmcasino am Hofgarten close to the conference venue. And the first session, chaired by Oliver Montenbruck from the DLR, certainly required a clear focus as we were taken through the use of GNSS in space geodesy, space navigation and reflectometry.

    Roland Pail from the Technical University, Munich described results from the satellite gravity missions GRACE and GOCE that looked at mass transport processes on our dynamic Earth. A particularly sobering animation showed the extent of ice mass loss from Greenland over the past decade. But what is role of gnss here? The ability to give precise positioning of the satellites and the fact that the satellite orbits carry information on the gravity field.

    Atmosphere sounding using GNSS radio occultation allows precise atmospheric profiles with global coverage in all-weathers. Jens Wickert of the Helmholtz Centre Potsdam said that since 2006 these high vertical resolution profiles had been making a significant impact on the world’s weather forecasting including improved hurricane forecasts. It was also a bias free technique for observing global temperature change. With a multi-GNSS future new missions could be planned as more signals would reduce noise. Combining GNSS and reflectometry could enable accurate tsunami detection from space. Similarly Prof Antonio Rius from Barcelona was using reflected GNSS signals to determine data on the surface of the sea such as surface roughness, extent of sea ice and early warning of a tsunami.

    Stefan Sassen of Airbus Defence & Space described the LION GNSS navigation receiver for MEO and LEO platforms. The unit was qualified since 2014 and now 50 were on order. LION is highly flexible with multi-frequency, multi-constellation and multi-antennae configurations possible. It was accurate enough for autonomous orbit raising (a few kms) and or station keeping (to within 100cm).

    Finally Manfred Sust of RUAG Space GmbH said that space borne gnss receivers were true enabling technologies for Earth Observation missions as precise orbit determination was key to capturing sharper images.

    Alternatives

    The second session of the day returned to the practical issues around possible alternative or complementary PNT (APNT) systems. As GNSS becomes ubiquitous many terrestrial PNT systems are being decommissioned (LORAN, VOR), but the potential vulnerability of GNSS signals to interference is highlighting the need for backup. The challenge being to balance functionality and cost in the search for “plan ‘B’ for GNSS” as chairman Michael Meurer from DLR described it.

    The FAA’s Deborah Lawrence reiterated her plans for scoping and implementing a backup system to cope with a GPS outage in the US. The FAA is currently engaging with stakeholders to define what the minimum operational target for a GPS outage should be to set the basis for procurement activity. The timeline for a final investment decision was now December 2018.

    For Europe Gerhard Berz of Eurocontrol thought there were many potential APNT in place and the topic was in the SESAR 2020 research programme. He thought existing DME could potentially do the job in Europe as it had good coverage, but the challenge is to get good geometry and coverage at low altitudes, in remoter areas and over water.

    Prof Per Enge of Stanford University “put the moose on the table” and pointed to the 978 and 1030 ranging frequencies as an existing system that could be used for positioning. But how accurate was it? Airborne experiments had shown good agreement with GPS positioning with an accuracy of around 100m and in turns 300m, which was good enough in an emergency. Further tests using a UAV at spider infested Camp Rogers had demonstrated APNT in flight with 50m error. The UAV itself was specifically developed to navigate using APNT while looking for GNSS jammers.

    Wouter Pelgrum of Ohio University discussed the relative merits of eLORAN, which has high power – and therefore difficult to jam – and beyond line of site accuracy of less than 10m, and alternatives such as collocation of pseudolites with mobile phone cell towers. This could also enable high accuracy indoors positioning applications. He believed that APNT will need to be context specific and there was no single solution.

    Belabbas Boubeker of the DLR discussed modular APNT concepts while Nick Ward of the UK’s General Lighthouse Authorities indicated there was no coordinated policy on resilient PNT in the European maritime sector at present but his authority and others were exploring the possibility of using eLORAN as a commercial enterprise. Nine transmitters were operational in Europe and the service had been declared in 2014.

    Michael Hoppe of Fachstelle der WSV für Verkehrstechniken said resilient PNT was a core element of e-navigation for waterways. A combination of techniques such as medium frequency RF, AIS and eLoran could give good accuracy in areas of highest traffic. First results of trials were encouraging.

    Processing Power

    The final session of the Summit to grab my full attention was chaired by Frank van Diggelen of Broadcom. He led a wide ranging debate on GNSS receiver architecture trends and more generally the future of chip design and fabrication: are we approaching the end of Moore’s law and if so — what next?

    Recently “The balance of power has moved back onto the GNSS chip” to enable lower device power use. To highlight current developments Frank described a couple of Broadcom products: the Broadcom 4773 “location hub” that is at the heart of the Samsung Galaxy 6 “super smart phone” and the 4774 that can access signals from all four GNSS constellations and will be shipping in early 2016 on new smartphones.

    In fact earlier this year the 4774 was used to make a first fix using signals from four different GNSS constellations (with signals from one each of GPS, GLONASS, Galileo and BEIDOU satellites) and a significant event in terms of our multi-constellation future.

    Greg Turetzky of Intel talked about the benefits and challenges for GNSS in advanced silicon processes. He noted that Intel is now shipping 14nm technology and plans were in hand for the next two generations (10nm and 7nm). Moore’s law has been a great enabler for modern society. If automobiles had taken a similar development in the same timeframe we would all be driving cars with a maximum speed of some 300 000 km/hour that cost us around 4 cents to buy!

    The big challenge for GNSS architecture was to take advantage of the smaller geometries while greatly reducing standby power. The integration of multiple radio sources to provide a single location solution was key giving ubiquitous location capability that will improve the experience of every mobile product.

    Looking into his crystal ball, Peter Anderson of Integrated Navigation Systems in the UK saw that integrating signals from complimentary technologies and sensors would be important but would lead to a greater demand for digital processing. He predicted that multiband receivers would become standard in consumer devices. He also pointed out that the worst potential source of GNSS jamming for a smartphone was the phone itself! The move to dual frequency would be helpful here.

    An overview of the Chinese XIHE system for seamless outdoor and indoor location was given by Dongkai Yang of Beihang University. This Beidou Innovative application provides a LBS system based on gnss and mobile communication networks to give a “fusion of communication and positioning for indoor positioning”. The system is being demonstrated in four areas in China in shopping malls. The target for positioning accuracy in the system is for less than 3 metres indoors and less than 1 metre outdoors.

    Franz Kreupl of Munich Technical University gave a sobering view of “life after silicon” – essentially it looks like there isn’t one. He outlined the limits to silicon technology such as tunnelling current and predicted some further progress could be made in reducing interconnect sizes and via circuit design. But new candidate materials for semiconductor electronics from carbon nanotubes to widely hailed 2-D materials graphene and MoS2 all suffer major issues that seem to make them non-starters.

    But do we need to keep on miniaturizing? Norbert Schuhmann of Fraunhofer IIS in Nuremberg thought that technology downscaling would have an end in terms of the physics, but especially in terms of reasonable cost. He thought 7nm and 2020 was the end point for the physics but that in fact 28nm should be seen as the actual last node in Moore’s law as from then scaling has no longer also been the path for cost reduction. He saw silicon on insulator technology and monolithic 3-D integration as possible paths forward, but the technology sweet spot — and well suited for GNSS — was 55nm and a format that was already extensively used in automotive applications.

  • BeiDou Launch Expected Monday

    News courtesy of the CANSPACE Listserv.

    The launch of the next BeiDou satellite is predicted to occur at about 13:45 UTC on Monday, March 30.

    The new BeiDou satellite would be the fifth GNSS satellite planned for launch by the end of the month, joining GPS Block IIF-9 (launched Wednesday), Galileo 7 and 8 (planned for launch Friday) and IRNSS-D (planned for launch Saturday, March 28).

  • BeiDou Launch May Take Place This Month

    BeiDou Launch May Take Place This Month

    News courtesy of the CANSPACE Listserv.

     

    The first satellite in the BeiDou Phase 3 expansion could be launched by the end of March. Apparently, a BeiDou satellite has been shipped to the Xichang launch site, and tracking ships have left port for the open ocean.

    Also, a philatelic first-day cover for the launch (a common Chinese practice) has been issued with a March 2015 inscription. This is likely a launch of a medium Earth orbit (MEO) satellite.

    The new BeiDou satellite would be the fifth GNSS satellite planned for launch by the end of the month, joining GPS Block IIF-9 (March 25), Galileo 7 and 8 (March 27) and IRNSS-D (March 29).

    Below is the first-day cover.

    BDS-3_M1_launch_cover.jpg
    First-day stamp cover for BeiDou commemorates an upcoming MEO launch. Photo: BeiDou

     

     

     

  • In GNSS Race, Could Galileo Be Surging into Second?

    In GNSS Race, Could Galileo Be Surging into Second?

    Editor’s Note: Alan Cameron is editor-in-chief and publisher of GPS World magazine. He also writes the monthly GNSS Design & Test newsletter. The views expressed are his own.

    “It’s tough to make predictions, especially about the future.” This insight comes from the 20th-century American sage Yogi Berra. Yet predictions — hedged guesses, if you will — form the basis of nearly all new business ventures and decisions in ongoing business activities.

    For surveyors in the year 2015, one of the key predictions — or guesses — to make concerns the next GNSS to come predictably and reliably online, to augment GPS where GPS alone does not fully function: under canopy, in dense urban environments, and so on. More satellites visible at more varied angles in the sky can help surmount these obstructions.

    Staking the future of one’s business, in the form of new equipment acquisition, in such an environment is a bit like betting on a long-distance horse race. First one steed surges to the head of the pack, then it falls back as another charges forward. We have seen this pattern repeatedly in the growth of GLONASS, Galileo and BeiDou.

    Some may say that GLONASS, the Russian system, has already won the race (the first heat, at least) and currently fills the role of GPS partner in precision surveying. It does, to some extent, but its future viability is cloudy — and its past record is patchy, to say the least. It rose to full operational capability around the turn of the century, then fell very, very low in numbers as short-lived satellites expired and were not replaced at sufficient rate. Recently, GLONASS has mounted a resurgence, but that has been marred by repeated launch failures and a disturbing anomaly. It cannot be counted or confirmed a winner, yet.

    I spoke yesterday with an expert and veteran professional land surveyor who expressed the opinion that the manner in which surveying is conducted will change more in the next five years than it has in the last 25. Keep in mind that the last 25 years saw enormous changes themselves, as GPS significantly transformed, upgraded and made vastly more efficient most surveying activities.

    Betting on a horse race in such a rapidly changing environment becomes even more chancy.

    Here’s a tip from a racetrack tout: don’t count Galileo out.

    GLONASS we recounted briefly above. BeiDou recently achieved a regional operations status over Eastern Asia, but further developments there have been puzzlingly quiet for some time.

    The European system has come on with agonizing slowness since the year 2000, suffering many delays and most recently what could have been a debilitating failed dual launch. But the combined strength of the European Union continues to push determinedly forward, and the program has an ambitious schedule with an eye firmly fixed on operability. And some recent research results tend — perhaps — to substantiate the claim, long pooh-poohed by those in the United States, at least, that Galileo will eventually prove “better” than GPS. Details further on.

    What might a prudent yet pragmatic, forward-looking surveying firm do in this uncertain environment, where the only certainty is change, and likely to be rapid change at that? Here’s another racetrack tip: don’t make any big bets just yet, but study the field closely and continuously. In particular, watch Galileo’s performance.

    A further item to be checked in Galileo’s favor: its system operators have long been in close talks with the U.S. government on many matters involving co-operation and interoperability. As recounted in a recent story concerning the Federal Communications Commission’s surprising role in this matter, the Europeans are filling out the proper forms for full accreditation within the United States. This could turn out to be important in business operations.

    Back to studying the field closely: also study leading manufacturers’ offerings in this regard. They also are making bets on the future; quite possibly they have better information, and/or have done more extensive analysis of what information is available, paired with in-depth, highly technical research and development of signal characteristics and how signals from disparate GNSS can be most productively combined.

    A quick scan of GPS World’s 2015 GNSS Receiver Survey shows the following key manufacturers (among others) have GPS receivers now commercially available that are Galileo-ready: Altus Positioning Systems, Ashtech, Geneq, iFEN, JAVAD GNSS, Leica Geosystems, NovAtel, NVS Technologies, Septentrio, Sprecta Precision, Spectrum, Topcon, and Trimble.

    Better than GPS???

    Supporters of Galileo have long raised hackles west of the Atlantic with claims that Galileo would provide better accuracy than GPS. Not! cried the faithful, and especially not when the modernized and improved, strengthened, more accurate GPS III signals are coming along just as fast if not faster than Galileo. Recently the pace of GPS III has come into question; can the Gold Standard and clear leader for 25+ years really be falling back into the pack?

    σ(pr_gnd) versus elevation for Galileo E1 (dotted lines) and GPS L1 (solid lines for different smoothing constants: red (10s), green (30s), cyan (60s), purple (100s).
    σ(pr_gnd) versus elevation for Galileo E1 (dotted lines) and GPS L1 (solid lines for different smoothing constants: red (10s), green (30s), cyan (60s), purple (100s).

    Let’s disregard that question for the time being, and look at some recent research, to be reported in full in the cover story of GPS World magazine’s April issue, out soon. In it, the authors (two German and one American researcher) report:

    “Analysis of new Galileo signals at an experimental ground-based augmentation system (GBAS) compares noise and multipath in their performance to GPS L1 and L5. Raw noise and multipath level of the Galileo signals is shown to be smaller than those of GPS. Even after smoothing, Galileo signals perform somewhat better than GPS and are less sensitive to the smoothing time constant.”

    This is all pretty arcane and a bit removed from current field of operations, as far as surveyors are concerned. But it does signal something, and it provides food for thought.

    The researchers obtained their results using four JAVAD Delta receivers, all connected to Leica AR 25 choke ring antennas.

  • BeiDou Numbering Presents Leap-Second Issue

    Leap-Second-O

    During preparation of playback scenarios for the upcoming leap-second event taking place in June, engineers at Racelogic identified a potential pitfall for GNSS engineers. The difficulty arises from the fact that BeiDou uses a different “day number” for the date to apply the leap second, compared with GPS and Galileo. GPS and Galileo use 1-7 as week day numbers, and BeiDou uses 0-6.

    If this fact has been missed during development, then the result is that the leap second may be implemented a day early on GNSS engines that are tracking the BeiDou constellation, said Mark Sampson, product manager for Racelogic.

    “We tested four different Beidou enabled receivers, from four leading GNSS companies, and none of them appeared to handle the Beidou leap second correctly. This included an engine which originates from China!” Sampson said. “We have since been in contact with two of these companies, who have confirmed that their hardware does have a bug in the leap-second code due to the numbering of the days.”

    The error presents itself when the receiver is running on the BeiDou constellation alone, and when the date is June 29 of this year. In some cases, the BeiDou leap second will be adjusted from 2 to 3 seconds from midnight on June 29, which should in fact occur on midnight of June 30. This will result in an error for the reported UTC time of 1 second for the period of this day. In other cases, the leap second was not implemented at all when running on BeiDou alone.

    “We have also checked the output of a BeiDou signal generator from a different simulator company, and this too uses the 1-7 range for the BeiDou leap-second date instead of the correct 0-6 range,” Sampson said. “This may explain why a number of commercial receivers appear to have been caught out by this issue.”

    Racelogic LabSat3 simulator.
    Racelogic LabSat3 simulator.

    In order to help companies test for this problem, Racelogic has generated simulated RF data for June 29 and 30, starting 15 minutes before midnight. “We have two sets of files. One set contains BeiDou only signals and the other contains a combination of BeiDou and GPS signals,” Sampson said. “Note that on some of the receivers we have tested, when GPS is being tracked as well, the GPS leap-second message overrides the one coming from BeiDou and applies the leap second correctly.”

    The scenarios are compatible with Racelogic’s LabSat3 triple constellation simulator, which is available on a free 15-day loan or can be purchased from Racelogic.