About Richard B. Langley
Richard B. Langley is a professor in the Department of Geodesy and Geomatics Engineering at the University of New Brunswick (UNB) in Fredericton, Canada, where he has been teaching and conducting research since 1981. He has a B.Sc. in applied physics from the University of Waterloo and a Ph.D. in experimental space science from York University, Toronto. He spent two years at MIT as a postdoctoral fellow, researching geodetic applications of lunar laser ranging and VLBI. For work in VLBI, he shared two NASA Group Achievement Awards.
Professor Langley has worked extensively with the Global Positioning System. He has been active in the development of GPS error models since the early 1980s and is a co-author of the venerable “Guide to GPS Positioning” and a columnist and contributing editor of GPS World magazine. His research team is currently working on a number of GPS-related projects, including the study of atmospheric effects on wide-area augmentation systems, the adaptation of techniques for spaceborne GPS, and the development of GPS-based systems for machine control and deformation monitoring. Professor Langley is a collaborator in UNB’s Canadian High Arctic Ionospheric Network project and is the principal investigator for the GPS instrument on the Canadian CASSIOPE research satellite now in orbit.
Professor Langley is a fellow of The Institute of Navigation (ION), the Royal Institute of Navigation, and the International Association of Geodesy. He shared the ION 2003 Burka Award with Don Kim and received the ION’s Johannes Kepler Award in 2007.
Posts by Richard B. Langley
Analysis of Signal Tracking Techniques for Multipath Mitigation
Researchers involved with ARTEMISA describe their efforts to generate synthetic multipath of GPS L1 and Galileo E1 signals and to test different signal tracking techniques in a simulated receiver to see which techniques best minimize the effects of multipath on positioning solutions. Read more»
Accurately Tracking Smartphones IndoorsIf we wish to obtain consistently usable positions indoors using a mobile phone, we can augment its GPS or GNSS receiver with other unfettered sensing technologies such as gyroscopes and accelerometers supplemented by radio signals of opportunity. But is all of this actually feasible? The authors have conducted tests of a multi-system approach to positioning indoors with favorable results. Read more»
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... Read more»
Synthetic-Aperture GNSS Signal ProcessingWe 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»
By Richard B. Langley Update (July 29, 2013): The spectrum recorded by the German Aerospace Center researchers appears to be consistent with a combination of BPSK(1) and BOC(5,2) modulation. This... Read more»
The International GNSS Service MGEX CampaignGPS is almost 40 years old. While mass consumer use of GPS began only within the past decade or so, GPS was "born" during the Labor Day weekend of 1973, when about a dozen military officers and industry analysts under the leadership of Brad Parkinson met to consolidate the concept for a single satellite-based navigation system for the U.S. Department of Defense. Their proposal for NAVSTAR GPS was approved on December 22, 1973. The first satellite to be launched under the GPS program, on July 14, 1974, was the Naval Research Laboratory’s Navigation Technology Satellite (NTS) 1. Read more»
It's a hostile (electronic) world out there, people. Our wired and radio-based communication systems are constantly under attack from evil doers. We are all familiar with computer viruses and worms hiding in malicious software or malware distributed over the Internet or by infected USB flash drives. Trojan horses are particularly insidious. These are programs concealing harmful code that can lead to many undesirable effects such as deleting a user’s files or installing additional harmful software. Such programs pass themselves off as benign, just like the “gift” the Greeks delivered to the Trojans as reported in Virgil’s Aeneid. This was a very early example of spoofing. Read more»
Generating Distorted GNSS Signals Using a Signal SimulatorIn this month’s column, our authors discuss a set of GPS and Galileo evil-waveform experiments they have carried out with an advanced GNSS RF signal simulator. Their results will help to benchmark the effects of distorted signals and perhaps lead to improvements in GNSS signal integrity. Read more»