Signal Processing

Galileo Achieves First Airborne Tracking

December 12, 2013By
Aircraft position as obtained by Galileo-only receiver during Netherlands flight.

The European Space Agency’s Galileo satellites have achieved their first aerial fix of longitude, latitude and altitude, enabling the inflight tracking of a test aircraft. ESA’s four Galileo satellites in orbit have supported months of positioning tests on the ground across Europe since the first fix in March. Now the first aerial tracking using Galileo has taken place, marking the... read more

UNB Technology Space Launch Delayed

September 16, 2013By

Update: Elon Musk, SpaceX’s CEO and chief designer, has posted an update on the status of the upcoming Falcon 9 launch on his Twitter account. “Will do another static fire of rocket to make sure all is good & AF [[Air Force]] needs to test ICBMs, so probable launch Sept 29/30,” Musk tweeted. “The static fire is scheduled for later... read more

The System: IRNSS Signal Close up

September 1, 2013By and

IRNSS Signal Close up By Richard Langley, Steffen Thoelert, and Michael Meurer The spectrum of signals from IRNSS-1A, the first satellite in the Indian Regional Navigation Satellite System, as recorded by German Aerospace Center researchers in late July, appears to be consistent with a combination of BPSK(1) and BOC(5,2) modulation. Figure 1 shows that, centered at 1176.45 MHz, the signal... read more

This article is tagged with , , , , and posted in Design & Test, Signal Processing, The System

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

This article is tagged with , , , and posted in From the Magazine, GNSS, Signal Processing

GNSS and Radio Astronomical Observations

August 1, 2013By

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

On the Road under Real-Time Signal Denial

May 1, 2013By
Figure 1 innovITS Advance test circuit (right) and the environment it represents (left).

Emerging GNSS applications in automobiles support regulation, security, safety, and financial transactions, as well as navigation, guidance, traffic information, and entertainment. The GNSS sub-systems and onboard applications must demonstrate robustness under a range of environments and varying threats. A dedicated automotive GNSS test center enables engineers to design their own GNSS test scenarios including urban canyons, tunnels, and jamming sources at a controlled test site. read more

GNSS Test Standards for Cellular Location

May 1, 2013By
Downtown Seattle, a typical test-case environment.

GNSS receivers in cell phones will soon support four or more satellite constellations and derive additional location measurements from other sources: cellular location, MEMS sensors, Wi-Fi, and others. The authors propose test standards covering these sources, meeting industry requirements for repeatable testing while considering the user experience. read more

This article is tagged with and posted in From the Magazine, Mobile, Signal Processing, Wireless Infrastructure

Innovation: Interfacing Clearly

April 1, 2013By

A New Approach to the Design and Development of Global Navigation Satellite Systems
In this month’s column, a team of authors affiliated with the Galileo project discusses the Interface Communication Modeling Language, an extension of UML that allows engineers to clearly represent SIS interfaces, critical for the design of GNSS receivers. read more