Our Man in the Baltic: Report from the European Navigation Conference

April 25, 2012  - By 0 Comments

GDANSK, POLAND — Poland has emerged as a regional leader for Eastern Europe. Among all European countries, it ranks fourth in population and ninth in the size of its national economy. This year, the European Navigation Conference (ENC), which rotates each year to a different host country, has convened in Gdansk, Poland — its first time in Eastern Europe.

Gard Ueland, president/CEO for Kongsberg Seatex and the chairman of Galileo Services, opened his keynote address at the 2012 European Navigation Conference with the statement “GNSS applications and services are the best growth opportunity for Europe.”

Was anyone from the European Space Agency (ESA) or the European Union’s GNSS Supervisory Agency (GSA) listening? They were not, because neither body bothered to attend this ENC — the first time I can recall either organization absenting themselves from this important, top-level technical conference. ESA and GSA presented themselves in significant numbers and seniority at the Munich SatNav Summit in March, on the stage and in the audience. But then money, influence, and visibility (they may all amount to the same thing) are more in circulation at Munich. The ENC merely gathers the researchers and application developers who are doing the real work that will eventually field users and grow markets.

Ueland of Galileo Services was careful to differentiate his topic as separate from satellite-system development per se. He focused on developing applications, the downstream segment that will lead, he said, to new business activities, jobs and wealth creation, and a bigger GNSS market share.

According to a GSA study completed in 2011, the 2010 global GNSS market was 130 billion euros, and of that amount, the European market share in the GNSS sector was 20 percent.  “A little bit less than what Europe is used to,” Ueland remarked; that accustomed share is 1/3 of the market.  Naturally, Ueland called for further public-sector investment in satnav R&D, which has been the rallying cry of Galileo Services.

In 2020, global GNSS market is estimated to reach 240 billion euros. “Europe will be challenged even to maintain its current share of 20 percent. If we were to succeed in reclaiming the 1/3 share, it would translate into 400,000 jobs in Europe. This is something that Europe needs.”

A position paper, “Satellite Navigation Applications,” goes into further details and is available at www.Galileo-services.org.

Ueland concluded that at the EU level there is a need for a dedicated budget line within Horizon 2020 for GNSS application R&D.

In subsequent talks at the ENC plenary session, Prof. Janusz Zielinski of the Space Research Center of the Polish Academy of Sciences discussed Polish activity in EGNOS and the Galileo program.

Dr. Heidi Kuusniemi of the Finnish Geodetic Institute gave a presentation on the effects of GNSS Jammers on consumer-grade satnav receivers, showing the initial results from research started this year.  Jammers, though illegal in most countries, are gaining popularity for financial reasons, to avoid road tolling and insurance billing, as well as personal privacy reasons, to avoid tracking and location-based monitoring.

The Finnish Geodetic Institute analyzed the effects of a $130 L2 and L5 jammer and a $14 L1 jammer on two ublox and two Fastrax consumer-grade reciever, a receiver found inside a Nokia smartphone, and a high-precision professional-grade NovAtel OEM4 L1/L2 receiver.

Horizontal errors up to 130 meters were observed on the consumer grade receivers, and availability decreased to 16 percent in 24 hours. Effects on the one combined GPS/GLONASS consyumer receiver, from Fastrax, were not as pronounced as on the other consumer-grade receivers. In the professional case, accuracy was degraded up to 80 meters, and availability decreased to around 26 percent over 24 hours.

After outlining some jamming detection and mitigation solutions, Kuusniemi concluded that in-car jammers are a serious threat, and steps must be taken against the use of jammers.  Future GNSS will have improved resistance to interference, for several reasons.

Davide Margaria of the Institute Superiore Mario Bella (NavSAS group) presented on research regarding “Acquisition and Tracking of Galileo IOV E5 signals,” which are important for the safety-of-life service planned by Galileo.

The Galileo satellite system currently consists of GIOVE-A and  B, the two experimental satellites dating from 2005 and 2008, and the two in-orbit validation (IOV) satellites launched in November 2011, the Proto-Flight Model (PFM), and the Flight Model 2 (FM2).

The FM2 satellite has started transmitting E5 navigation signals in recent weeks. E5 is an alternative binary offset carrier: AltBOC(15,10) modulated signal, multiplexing 4 channels in two adjacent sidebands, E5a and E5b: two data channels and two pilot channels. Each sideband can be separately demodulated as a QPSK-like signal.

Using a flexible experimental E5a/E5b COTS front end, NavSAS researchers separately received each sideband, with IF samples transferred for real-time processing, and stored for post-processing.  Signals were acquired and tracked for multiple satellite passes of all four satellites.

In an analysis of the E5b signals, both data and pilot channels, they found estimated C/N0 values to be consistent with the satellite elevation patterns and with expected values from the Galileo ICD specifications.

The PFM and FM2 signals were received at approximately 3 dB stronger than the GIOVE-A and B signals. The team further found the presence of secondary code chips and successfully decoded the I/NAC navigation message on the data channels. Their future activities include checking the F/NAV data pages transmitted on the E5a band, and setup of a wideband experimental front-end for coherent E5 processing.

In technical sessions on the first afternoon, I found the following presentations of  salient interest.

Byung Hyun Lee from Konkuk University in Korea presented “Performance Analysis of Doppler-Aided GPS/QZSS Precise Positioning for Land Vehicles,” designed for which-lane positioning in urban environments.  Using Doppler measurements to compensate for restrictions of carrier-phase measurements, traditional RTK techniques, for precise positioning.  Needed for this application are reliable single-epoch measurements and velocity estimation. Double-differenced Doppler measurements yield this quality enhancement.

Using NovAtel FlexPack 6 equipment for rover and reference station, the author and colleagues found sufficient accuracy results with GPS-only in a relatively benign environment, with an HDOP of 1.505 and 7 available satellites. In a difficult or “bad” environment, GPS –only had a HDOP of 6.84 and insufficient accuracy for the which-lane requirement.

However, using GPS and QZSS in the same “bad” situation brought an HDOP of 1.564 and sufficient accuracy for lane-specific car navigation.

Pawel Kicman of the Warsaw University of Technology presented the TALOS Navigation Research Electric Car using COTS components. The vehicle was developed for land-border surveillance using one autonomous robot to monitor industrial perimeters, and a second robot to intercept intruders. The adapted golf cart has a suite of installed sensors: satellite (NovAtel SPAN for GPS/GLONASS integrated with tactical grade IMU), inertial (low-grade IMUs), magnetic, visual (cameras and laser rangefinders), and odometric.

 

The researchers, including a student team, obtained sufficient accuracy for the application, provided hands-on experience, and offers many prospective research projects, leading to development of autonomous driving on the vehicle, since all the sensors and control capabilities are there.

Robert d’Aystetten from Sprint in Poland (the company is not the same nor is it a subsidiary of the U.W. wireless carrier Sprint) described an eco-driving algorithm for fleet applications to promote safe and efficient driving habits, using car-tracking data from a number of sensors to construct a driver’s profile and detect “overlimits.” The application assigns motivational points to every driver in the company (it has a fleet of nearly 500 vehicles) for eco-driving — efficient acceleration, braking, and cornering — speed, and generated alerts. In addition to maintaining and improving organizational driving standards, the data can be used by insurance companies to prepare better insurance offers based on actual profiles and driver performance.

The VIZAN SOFIT tracking device employs real-time GPS tracking and positioning; GPRS location data transfer to the server; smart algorithm of data acquisition (time, distance and angle based); acceleration detection (e.g. in case of sudden braking); speed measurement; internal memory for location data storing in case of GSM signal loss; accurate distance counter (independent from track points settings); digital and analogue inputs and outputs (fuel level, door status etc.); 1-Wire iButton for driver identification; voice communication; multiple geofence zones; eco-driving algorithms; and driver’s profile data.

Ciro Gioai of the Parthenope University of Naples discussed Aided GPS/GLONASS navigation in urban environments.  February 2012 tests of pedestrian subjects carrying a NovAtel FlexPak-G2 with an Antcomm antenna, using least-squared and Kalman-filter techniques, obtained accuracies in the range of 5 to 7 meters in difficult urban environments, and good vertical accuracy as well, with as few as three visible satellites from the combined systems. Future works will incorporate Galileo measurements in addition to GPS and GLONASS.

Prof. Jacek Januszewski of Gdynia Maritime University rhetorically asked how many Galileo satellites will provide achieve sufficient accuracy and availability for the user? In particular light of the fact now that, according to ESA, 18 satellites on orbit will constitute initial operational capability (FOC) of the system, predicted for 2015.  He also presented results with 22 and 26 satellites.

The results were disheartening, to say the least.

He concluded that with 18 satellites, minimum satellite availability cannot be obtained in all geographic zones, in different latitudes, at 10 degree and 5 degree masking. In a 25-degree masking zone, 26 satellites yielded only 3 satellites, not sufficient for positioning; only a 27-satellite constellation proved satisfactory.

In European latitudes (50 to 60 degrees latitude), distribution of satellite azimuths is practically the same for different numbers of satellites. The percentage of satellite visible above angle H is for all constellations is practically the same for different numbers.

For 18 satellites, 3D positioning is only available in the zone 80-90 degrees latitude, with a masking of 0 degrees.

For a 22-satellite constellation, positioning depends on zero masking, 3D position in all zones.  With 5 degree masking, 3D is avaialable in some zones only, 2 dimension positioning in all zones.

With 26 satellites, if masking is less than or equal to 15 degrees, there is 3D positioning in all zones. If masking is 25 degrees, 3 D in zone 80-90 degrees only.

With 27 satellites, 3D position is provided in all zones, for up to 25 degree masking.

In one of the last presentations of the day, Ted Driver of AGI discussed Operational Considerations for Improved Accuracy with an IOC Galileo Constellation.  He told the audience that during Galileo’s IOC phase, the dilution of precision (DOP) will not be ideal and indeed may have severe spikes several times during the day, globally.

His paper focused on two components of navigation accuracy that the Galileo Control Center can manipulate to improve overall accuracy for users: selectively timing uploads of the orbital ephemeris and clock state predictions.  That is, doing so with great regularity. Ideally, these orbit and clock predictions would be updated continuously, but that cannot be achieved operationally.

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