From the Magazine

Directions 2014: On the Path to Early Services

November 26, 2013By
Galileo-2-O

By Eric Chatre, Horst Faas, and Marco Lisi With four satellites in space, launched by pairs in October 2011 and October 2012 from French Guiana, the Galileo project is now successfully completing the In-Orbit Validation (IOV) phase. The Galileo space, ground, and user segments have been qualified through extensive on-ground and in-orbit tests, and operations, of a core satellite constellation... read more

This article is tagged with and posted in Featured Stories, From the Magazine, Galileo

New Structure for GLONASS Nav Message

November 2, 2013By
Glonass-K-W

Russian scientists propose a new code-division multiple-access signal format to be broadcast on a new GLONASS L3 signal. Once implemented across the modernizing GLONASS constellation, this will facilitate interoperability with — and eventually interchangeability among — other GNSS signals. The flexible message format permits relatively easy upgrades in the navigation message, if required. read more

This article is tagged with and posted in From the Magazine, GLONASS

Putting the (ultra-low) Power in GeoFence

October 31, 2013By
malkos_opener_O

Users of smartphones, tablets, and other devices expect position with the highest level of accuracy, always available, with the least amount of power consumed. One recent improvement fulfilling this demand involves operating-system services for location on smartphones, and the evolution towards lower power solutions. read more

Real-Time GNSS Activities at ESA

October 28, 2013By
The ESA Navigation Office.

The European Space Operations Centre has taken on the roles of real-time analysis center, data provider, and analysis-center coordinator for the International GNSS Service’s Real-Time Service, providing a number of products combining data streams from multiple sources. read more

This article is tagged with and posted in Augmentation & Assistance, Featured Stories, From the Magazine, Galileo

Synchronized Ground Networks Usher in Next-Gen GNSS

October 1, 2013By
LocataLite installation showing Jps transceiver tower.

An integrated GNSS+Locata system installed on drills, shovels, and bulldozers — the full complement of high-precision machines on site — at Australia’s Newmont Boddington Gold Mine has increased positioning accuracy and availability, as well as mine operational efficiencies, demonstrating an improvement in availability over GNSS-only of 75.3 to 98.7 percent. read more

Innovation: Under Cover

September 1, 2013By
FIGURE 1. Artist’s impression of the synthetic-aperture GNSS system for surveying in a forest.

Synthetic-Aperture GNSS Signal Processing
We take a look at a novel GNSS signal-processing technique, which uses the principles of SAR to improve code and carrier-phase observations in degraded environments such as under forest canopy. The technique can simultaneously reject multipath signals while maximizing the direct line-of-sight signal power from a satellite. Along with a specially programmed software receiver, it uses either a single conventional antenna mounted, say, on a pedestrian’s backpack for GIS applications or a special rotating antenna for high-accuracy surveying. Want to learn more? Read on. read more

This article is tagged with , , and posted in Algorithms & Methods, From the Magazine, Innovation

Signal Quality of Galileo, BeiDou

September 1, 2013By
Figure 1. 30-meter high-gain antenna.

Future positioning and navigation applications of modernizing and newly established GNSSs will require a higher degree of signal accuracy and precision. Thus, rigorous and detailed analysis of the signal quality of recently launched satellites, including the discovery of any possible imperfections in their performance, will have important implications for future users. read more

GNSS and Radio Astronomical Observations

August 1, 2013By
VLA_DGilder1_med-W

An alternative tool for detecting underground nuclear explosions? By Dorota A. Grejner-Brzezinska, Jihye Park, Joseph Helmboldt,  Ralph R. B. von Frese, Thomas Wilson, and Jade Morton Well-concealed underground nuclear explosions may go undetected by International Monitoring System sensors. An independent technique of detection and verification may be offered by GPS-based analysis of local traveling ionospheric disturbances excited by an explosion.... read more