Global Navigation Satellite Systems Engineering, Policy, and Design
The third international colloquium on scientific and fundamental aspects of the Galileo program will take place at the Danish Design Center in Copenhagen, Denmark from August 31-September 2, 2011.
The deadline for receiving paper abstracts has been extended until April 15, 2011 and may be submitted online.
Listening to today’s panel discussion on GNSS spectrum issues — with the hopeful subtitle, “A Place Where Competitors Become Colleagues?” — brought to mind a metaphorical description of the GPS signal environment that I heard recently.
The Munich Satnav Summit discussion revolved around the growing pressure on GNSS from other RF users, such as LightSquared, desiring to set up in radionavigation satellite system (RNSS bands).
Somewhat embellished, the description was this:
By Inside GNSS
Despite the fact that China’s rapidly developing global navigation satellite system now has seven spacecraft in orbit intermittently broadcasting test signals, it is the only GNSS provider that has not yet published a draft version of its interface control document (ICD), although one has reportedly been completed for more than a year.
Against that background, any new source of information about the directions of the Compass design — official, semi-official, or other — draws special attention.
By Inside GNSS
Photo: Wikimedia CommonsAttorneys for LightSquared Subsidiary LLC submitted a proposed work plan on Friday (February 25, 2011) for analyzing potential interference to GPS devices. The plan, required by the FCC as a condition of its granting a waiver to its Ancillary Terrestrial Component (ATC) rule for mobile satellite services (MSS), proposes to establish a working group (WG) to study the GPS overload/desensitization.
By Inside GNSS
The first new-generation satellite GLONASS-K of the GLONASS navigation system has reached its targeted orbit, the Russian Federal Space Agency (Roscosmos) announced today (February 26, 2011).
The Soyuz-2.1b rocket lifted off from Plesetsk cosmodrome at 6:07 a.m. (Moscow time) this morning. The GLONASS-K spacecraft was carried into its planned orbit by a Fregat booster at 9:41 a.m. Moscow time, according to Roscosmos public affairs office, which reported that the satellite separated from the booster as planned.
By Inside GNSS
Pendulum GSG-55 SimulatorSpectracom has announced its new 16-channel GPS constellation simulator, the Pendulum GSG-55.
The latest in the Pendulum line of GPS receiver test instruments, the GSG-55 is able to simulate Satellite-Based Augmentation Systems (SBAS), such as the U.S. Wide Area Augmentation System and the European Geostationary Navigation Overlay Service (EGNOS).
By Inside GNSS
FIGURE 1 (a, b, c) & FIGURE 2For the complete story, including figures, graphs, and images, please download the PDF of the article, above.
In the early stages of developing space-based radionavigation, the spectrum compactness of ranging signals was not proclaimed among the material priorities. Conventional bi-phase shift keying (BPSK) modulations, although they consume a rather large amount of spectrum, were adopted as the basis for both GPS and GLONASS signals.
By Inside GNSS
Q: Why is acquisition of GNSS signals generally more difficult than tracking and what are the limiting factors?
A: A fairly good analogy of the difference between GNSS signal acquisition and tracking can be found in the rescue of victims of a sunken ship whose location is not accurately known. The first stage of the rescue attempt typically involves an aircraft flying a search pattern, which hopefully encompasses the location where the ship went down.
By Inside GNSS
FIGURE 1: Touching wavelet spectraFor the complete story, including figures, graphs, and images, please download the PDF of the article, above.
The use of GNSS for safety critical applications is gaining interest, particularly amongst aviation users, who probably have the most demanding requirements. The GNSS frequency band containing the Galileo E5 and GPS L5 signals is designated as an aeronautical radio navigation service (ARNS) band, which enjoys legal protection from other services not allocated to this frequency on a primary basis.
By Inside GNSS
For the complete story, including figures, graphs, and images, please download the PDF of the article, above.
Galileo receiver designers require formal interface specifications for the Galileo signal-in-space (SIS) in order to write unambiguous and accurate specifications for Galileo receivers. To compute their positions, Galileo receivers must be able to retrieve timing and orbital information from the data stream conveyed in Galileo analog signals.
By Inside GNSS
Spirent Communications, long established in the laboratory test marketplace with its line of navigation and positioning simulators, has extended its product development into real-world environments by introducing a GNSS record and playback system (RPS).
By Inside GNSS
NavCom Technology, Inc., has announced new capabilities for the SF-3050 multi-frequency GNSS receiver and Sapphire GNSS OEM board.
In addition to the integrated StarFire/real-time kinematic (RTK) GNSS capabilities, the SF-3050 and Sapphire now support single-frequency, multi-constellation operation, heading, and moving base station RTK operation that enables coordinated vehicle applications.
By Inside GNSS
Broadcom Corporation reports that for the first time it has been able to compute GNSS positions, using the first Quasi-Zenith Satellite System (QZSS) spacecraft. The Japan Aerospace Exploration Agency (JAXA) launched the Quasi-Zenith Satellite–1 (nicknamed Michibiki) on September 11 and recently started transmitting the QZSS ephemeris (orbital location coordinates).
By Inside GNSS
