Beginning of a cycle of innovation GLEN GIBBONS

Recent evolution of the ION Satellite Division’s flagship conference — named after GPS for the first 15 years, GPS/GNSS in 2003, and GNSS since 2004 – received triple validation at this year’s event: in the plenary session, in the content of the technical program, and in the multi-system products introduced at the exhibition.

A revived Russian GLONASS system and a European Galileo program on the eve of its first satellite launch have joined the US NAVSTAR Global Positioning System to usher in a new era in space-based positioning, navigation, and timing (PNT). But presentations at ION GNSS 2005 in Long Beach, California, revealed just how early in the process we are. Many years will pass before the full benefits of current GNSS modernization efforts are felt. More than 300 papers presented this year, counting those submitted for two off-site classified sessions held at Boeing’s Seal Beach facilities.

At the system level, each of the three GNSS programs reported new developments: earlier this year, the GPS Joint Program Office (JPO) broke the GPS Block III acquisition into two contracts – one for new satellites and one for upgrading the operational control segment. JPO plans to award those contracts in summer 2006, JPO Director Col. Allan Ballenger told the plenary session audience. Meanwhile, the first launch of the modernized Block IIR-M satellite had been rescheduled for September (and subsequently took place on September 26), the first Block IIF launch is now set for 2007, and Block III spacecraft will go into space beginning in 2013. The Block IIR-M satellite will be the first transmitting the new military signal (M-code) and a second open civil signal at the L2 frequency (L2C).

Luis Ruiz, a member of the technical division of the Galileo Joint Undertaking (GJU) that is overseeing this phase of the Galileo project, told that the GJU hopes to complete a contract by December for a concessionaire to complete and operate Galileo. The agency is negotiating with a consortium of leading European aerospace and telecommunications companies, with financial details of the concession expected to be completed by April or May 2006, Ruiz said.

Galileo program officials also finally have acknowledged that the system will not be fully operational until early 2011, two years late. With funding, satellites, and a concession contract nearly in hand, a new question appears to have replaced the previous ones at the top of the Galileo FAQ: Will Galileo really be built, or when will the first satellite be launched? Now the leading question for Galileo officials seems to be, “When will the Galileo ICD (interface control document) be completed and published and where can GNSS designers and manufacturers get a copy of it?” “We have published 90 percent of the Galileo [open signal] ICD and presented it in European standardization bodies,” Ruiz said . “Once intellectual property rights are put in place, the full ICD will be published.”

The Russian program GLONASS is the only one that has delivered in recent years on the schedule as planned. Following a brief period 1996 when a full constellation was operating on orbit, the Glonass constellation dwindled to fewer than eight operating satellites in 2001. A re-examination of the program a few years ago led to a new commitment by Russia to rebuild and modernize the system. It has 13 operating satellites. Since December 2003, a modernized spacecraft (GLONASS-M) has been broadcasting an open signal at L2 as well as at L1. Another GLONASS-M satellite is still undergoing on-orbit testing and two more are scheduled for launch on December 25. The Russian Space Agency plans to have 18 operational satellites on orbit and broadcasting by early 2008 and 21 satellites by around 2010, according to Sergey Revnivykh of Satellite Navigation Control Center’s Space Mission Center, Central Research Institute of Machine Building.

Another new GNSS program discussed at the plenary is Japan’s Quasi-Zenith Satellite System (QZSS), a regional constellation that would put three or more spacecraft into geosynchronous orbit. QZSS is designed to ensure a GPS-like signal high overhead for users in Japan’s challenging signal environments in large cities and mountainous terrain.The current program schedule calls for a first experimental QZSS satellite launch in 2008 and a second in 2009 with full deployment by the end of that year.

When all these efforts reach fruition by 2013, GNSS users will have access to more than 80 satellites transmitting three open signals and another set of encrypted services, some of which will be available commercially. Also, space- and ground-based augmentation systems will be operating in several regions: the U.S. Wide Area Augmentation System, the European Geostationary Overlay Service, Japan’s MSAT Space-based Augmentation System, India’s GPS and GEO Augmented Navigation (GAGAN), and Australia’s Ground-based Augmentation System (GRAS).

In addition to the progress in expanding and modernizing a complementary GNSS infrastructure, we may be entering a new era in which cooperation replaces – or, at least, accompanies – the currently competitive relationships. As plenary speaker Ray Swider – a U.S. Defense Department program analyst for GPS, positioning, and navigation – observed, “We need more political leadership. We need to be more frank and get our cards out on the table and figure out what this GNSS compatibility is all about.”

Amid the myriad papers on signal processing algorithms and multipath mitigation techniques, several avenues of technical exploration stood out. GNSS software radios, which first appeared in ION technical sessions a few years ago, continue to evolve steadily – primarily as analytical tools for product designers, but with the promise of commercial applications in their own right in the future.

At the exhibition, NovAtel released preliminary specs for an L1/E5a receiver card capable of tracking L1 and L5/E5a Galileo, GPS, or SBAS signals in either a stand-alone Euro card form factor or integrated into the company’s Galileo Test Receiver rack mount enclosure. Javad Navigation Systems announced its 72-programmable channel GeNiuSS chipset reportedly capable of tracking GPS and GLONASS L1/L2 C/A and P-code signals and Galileo L1, E5, and E6 signals. Topcon Positioning Systems introduced its 72-channel G3-Paradigm chipset that will be the basis for a new generation of Topcon GPS+ products and will first appear in the new Net-G3 reference receiver. Septentrio, which is under contract with ESA to develop Galileo test user equipment, offers its GeNeRx1, a combined GPS/Galileo receiver that can be flexibly configured to simultaneously track Galileo as well as GPS satellites in multi-frequency mode. And NordNav announced a Galileo Upgrade Package for its R-30 software receiver. GPS/inertial products were represented in the exhibition by several exhibitors including Honeywell, BAE Rokar, BEI Systron Donner, and Crossbow.

Glen Gibbons
Editor, Inside GNSS
glen.gibbons@comcast.net