Richard B. Langley

Professor
B.Sc. (Waterloo); Ph.D. (York)
Phone: 506-453-5142 E-mail
Geodetic Research Laboratory
CANSPACE

Richard Langley is a professor in the Department of Geodesy and Geomatics Engineering at the University of New Brunswick (UNB), 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. After obtaining his Ph.D., Dr. Langley spent two years with the Department of Earth and Planetary Sciences of the Massachusetts Institute of Technology where he carried out research in geodetic applications of lunar laser ranging and very long baseline interferometry.

Dr. Langley has worked extensively with the Global Positioning System. He is a co-author of the best-selling Guide to GPS Positioning published by Canadian GPS Associates and is a columnist and contributing editor of GPS World magazine. He has helped develop and present a number of seminar courses on GPS over the years. Dr. Langley has consulted extensively in the field of GPS with private companies and government agencies both in Canada and abroad.

Dr. Langley has held appointments to several national and international bodies including the Canada-wide Differential GPS Service Management Board and the The Institute of Navigation.

For his contributions to space geodesy, Dr. Langley shared two awards from the U.S. National Aeronautics and Space Administration. In 2004, he was made a fellow of The Institute of Navigation and in 2007, he was made a fellow of the Royal Institute of Navigation. In 2007, Dr. Langley also received The Institute of Navigation's Johannes Kepler lifetime achievement award.

Professional Activities

Chair, Canadian National Committee for International Union of Geodesy and Geophysics (IUGG) (92-97)
International Association of Geodesy (IAG) Fellow and Coordinator for Education Initiatives (95-99)
Member, Council of International Union of Surveys and Mapping (IUSM) (92-97)
Corresponding Member, International Earth Rotation Service (IERS), Paris (90-01)
UNB Representative for UNAVCO, the University NAVSTAR Consortium (87-02)
Member, International Association of Geodesy (IAG) Special Study Group 1.158 (GPS Antenna and Site Effects) (95-99)
Member, International Association of Geodesy (IAG) Special Study Group 1.159 (Use of GPS Positioning for Atmospheric Monitoring) (95-99)
National Member, International Association of Geodesy (IAG) Commission VIII, International Coordination of Space Techniques for Geodesy and Geodynamics (CSTG) (99-03)
Member, International Association of Geodesy (IAG) Ad Hoc Working Group on the Refractive Indices of Light, Infrared, and Radio Waves in the Atmosphere (99-03)
Member, International Association of Geodesy Inter-commission Study Group 1.2 (Use of GNSS for Reference Frames) (03-07)
Member, International Association of Geodesy Sub-commission 4.5 (Next Generation RTK) (03-07)
Member, IGS Galileo/GNSS Working Group (03-04)
Member, IGS Low Earth Orbiters Working Group (02-04)
Associate, Committee on Space Research (COSPAR)
Correspondent, International Union of Radio Science (URSI)
Member, National Research Council of Canada Committee on International Science, Engineering and Technology (01-07)
External examiner, University of the West Indies Department of Surveying and Land Information (99-03)
Contributing Editor, GPS World
Member, Canada-wide DGPS Service Management Board
Investigator, GEOIDE Network of Centres of Excellence
- ENV#14: Improvement of Precise and Reliable Kinematic GPS Positioning in Real-time over Long Distances for the Support of Bathymetric Surveys (Latest annual report) (99-02)
- ENV#17: Natural Hazards and Disaster Monitoring (99-02)
- RES#47: Airborne Gravity for Exploration and Mapping (AGEM) (99-01)
- SLM-ASR#27: Mapping the Ocean Surface with Geodetic and Oceanographic Tools (05-08)
- TDM-ASR#31: Next-generation Algorithms for Navigation, Geodesy and Earth Sciences under Modernized Global Navigation Satellite Systems (GNSS) (05-08)

Consultant to several Canadian and international private and government agencies. He was a partner in Canadian GPS Associates.

Senior Research Associate

Dr. Donghyun (Don) Kim

Postdoctoral Fellow

Dr. Marcin Uradzinski

Graduate Students

Current

Tomas Beran

Doug Godsoe

Eulalio Alberto Ortiz

Hyunho Rho

Luis Serrano

Thatchineswaran (Thatchan) Thirumurthi

Recently Graduated

Shen, Chunlin

Current Visitors

Dr. Hang Guo, Nanchang University

Recent Visitors

Valérie Kirouac, Université Laval

Menehould (Menou) Caux, Ecole Supérieure des Géomètres et Topographes

Simon Banville, Université Laval

Yun Wu, Wuhan University

Jiming Guo, Wuhan University

Stefan Dürauer, Technical University of Vienna

Mariangel Fedrizzi, Brazilian Space Agency

Etienne Orliac, Federal Polytechnic University of Lausanne

André Caffier, University of Bonn

Tamás Horváth, Technical University of Budapest

Zdenek Lukes, Czech Technical University

Sophie Hetet, Ecole Supérieure des Géomètres et Topographes

Selected Recent Papers and Reports

1994

Mendes, V.B. and R.B. Langley (1994). " A Comprehensive Analysis of Mapping Functions Used in Modeling Tropospheric Propagation Delay in Space Geodetic Data." KIS94, Proceedings of the International Symposium on Kinematic Systems in Geodesy, Geomatics and Navigation, Banff, Alberta, 30 August - 2 September 1994, The University of Calgary, Calgary, Alberta, pp. 87-98.

1995

Langley, R.B., W. Wells, and V.B. Mendes (1995). Tropospheric Propagation Delay: A Bibliography. 2nd Edition. Geodetic Research Laboratory, Department of Geodesy and Geomatics Engineering, University of New Brunswick.
Mendes, V.B. and R.B. Langley (1995). "Zenith Wet Tropospheric Delay Determination Using Prediction Models: Accuracy Analysis." Cartografia e Cadastro, No. 2, June 1995; pp. 41-47.
Mendes, V.B., J.P. Collins, and R.B. Langley (1995). "The Effect of Tropospheric Propagation Delay Errors in Airborne GPS Precision Positioning." Proceedings of ION GPS-95, the 8th International Technical Meeting of the Satellite Division of The Institute of Navigation, Palm Springs, CA, U.S.A., 12-15 September 1995; pp. 1681-1689.

1996

Collins, J.P. and R.B. Langley (1996). "Mitigating Tropospheric Propagation Delay Errors in Precise Airborne GPS Navigation." Proceedings of PLANS '96, the 1996 IEEE Position, Location and Navigation Symposium, Atlanta, GA, U.S.A., 22-26 April, 1996; pp. 582-589.
Collins, P., R. Langley, and J. LaMance (1996). "Limiting Factors in Tropospheric Propagation Delay Error Modelling for GPS Airborne Navigation." Proceedings of The Institute of Navigation 52nd Annual Meeting, Cambridge, MA, U.S.A., 19-21 June 1996; pp. 519-528.
Coster, A.J., A.E. Niell, F.S. Solheim, V.B. Mendes, P.C. Toor, R.B. Langley, and C.A. Ruggles (1996). "The Westford Water Vapor Experiment: Use of GPS to Determine Total Precipitable Water Vapor." Proceedings of The Institute of Navigation 52nd Annual Meeting, Cambridge, MA, U.S.A., 19-21 June 1996; pp. 529-538.
Niell, A.E., A.J. Coster, F.S. Solheim, V.B. Mendes, P.C. Toor, R.B. Langley, and C.A. Ruggles (1996). "Measurement of Water Vapor by GPS, WVR, and Radiosonde." Proceedings of the 11th Working Meeting on European VLBI for Geodesy and Astrometry at Onsala Space Observatory, Onsala, Sweden, 23-24 August 1996; Research Report No. 177, Department of Radio and Space Science with Onsala Space Observatory, Chalmers University of Technology, Göteborg, Sweden; pp. 96-101.
Chen, X., R.B. Langley, and H. Dragert (1996). "Investigation of Annual Variations in the WCDA GPS Solutions." Proceedings of ION GPS-96, the 9th International Technical Meeting of the Satellite Division of The Institute of Navigation, Kansas City, MO, U.S.A., 17-20 September 1996; pp.1809-1818.
Coster, A.J., A.E. Niell, F.S. Solheim, V.B. Mendes, P.C. Toor, K.P. Buchmann, and C.A. Upham (1996). "Measurements of Precipitable Water Vaporby GPS, Radiosondes, and a Microwave Water Vapor Radiometer." Proceedings of ION GPS-96, the 9th International Technical Meeting of the Satellite Division of The Institute of Navigation, Kansas City, MO, U.S.A., 17-20 September 1996; pp. 625-634.
Collins, J.P. and R.B.Langley (1996). "A Tropospheric Delay Model for the User of the Wide Area Augmentation System." Viewgraphs from a final contract report presentation at the University of New Brunswick on 1 October 1996.

1997

Bisnath, S.B. and R.B. Langley (1997)."An Introduction to the Proposed BOLAS Mission for Ionospheric Research." Proceedings of the IGS Analysis Center Workshop, Jet Propulsion Laboratory, Pasadena, Calif., U.S.A., 12-14 March; in press.
Bisnath, S.B., V.B. Mendes, and R.B. Langley (1997). "Effects of Tropospheric Mapping Functions on Space Geodetic Data." Proceedings of the IGS Analysis Center Workshop, Jet Propulsion Laboratory, Pasadena, Calif., U.S.A., 12-14 March; in press.
Coster, A.J., A.E. Niell, F.S. Solheim, V.B. Mendes, P.C. Toor, and R.B. Langley (1997). "The Effect of Gradients in the GPS Estimation of Tropospheric Water Vapor." Proceedings of The Institute of Navigation 53rd Annual Meeting, Albuquerque, NM, U.S.A., 30 June - 1 July; pp. 107-114.
Collins, J.P., S.B.Bisnath, and R.B. Langley (1997). GPS Multipath Assessment of the Hibernia Oil Platform. Final report on a study commissioned by Cougar Helicopters Ltd., St. John's, Nfld.
Collins, J.P. and R.B. Langley (1997). (Invited) "Estimating the Residual Tropospheric Delay for Airborne Differential GPS Positioning (A Summary)." Proceedings of the 1997 Scientific Assembly of the International Association of Geodesy, Rio de Janeiro, Brazil, 3-9 September; IAG Symposia, Vol. 118, Ed. F.K. Brunner, Springer-Verlag, pp. 331-336.
Collins, J.P. and R.B. Langley (1997). " Estimating the Residual Tropospheric Delay for Airborne Differential GPS Positioning." Proceedings of ION GPS-97, the 10th International Technical Meeting of the Satellite Division of The Institute of Navigation, Kansas City, MO, U.S.A., 16-19 September 1997; pp. 1197-1206.

1998

Coster, A.J., A.E. Niell, F.S. Solheim, V.B. Mendes, P.C. Toor, R.B. Langley, and C.A. Upham (1998). "The Westford Water Vapor Experiment: Accuracy Issues Involving the Use of GPS to Measure Total Precipitable Water Vapor." Preprints of the 10th Symposium on Meteorological Observations and Instrumentation, pp. J70-J75, held during the 78th Annual Meeting of the American Meteorological Society, Phoenix, AZ, U.S.A., 11-16 January 1998.
Komjathy, A., R.B. Langley, and D. Bilitza (1998). "Ingesting GPS-Derived TEC Data into the International Reference Ionosphere for Single Frequency Radar Altimeter Ionospheric Delay Corrections." Advances in Space Research, Vol. 22, No. 6, pp. 793-801.
Collins, P. and R. Langley (1998). "Atmospheric Investigations for WAAS: Troposphere." Viewgraphs of a presentation at UNB, Fredericton, New Brunswick, 6-7 April 1998.
Mendes, V.B. and R.B. Langley (1998). "An Analysis of High-Accuracy Tropospheric Delay Mapping Functions." Viewgraphs presented at the European Geophysical Society XXIII General Assembly, Nice, France, 20-24 April 1998. Paper published in Physics and Chemistry of the Earth, Vol. 25, No. 12, 2000, pp. 809-812.
Mendes, V.B. and R.B. Langley (1998). "Optimization of Tropospheric Delay Mapping Function Performance for High-Precision Geodetic Applications." Proceedings of DORIS Days, Toulouse, France, 27-29 April 1998 (viewgraphs).
Mendes, V.B. and R.B. Langley (1998). "Tropospheric Zenith Delay Prediction Accuracy for Airborne GPS High-Precision Positioning." Proceedings of The Institute of Navigation 54th Annual Meeting, Denver, CO, U.S.A., 1-3 June 1998; pp. 337-347. A slightly revised version was published as "Tropospheric Zenith Delay Prediction Accuracy for High-Precision GPS Positioning and Navigation", Navigation, Vol. 46, No. 1, Spring 1999; pp. 25-34.
Collins, J. and R. Langley (1998). "Atmospheric Investigations for WAAS – Troposphere" Viewgraphs of presentation at the FAA Tech. Center, Atlantic City, N.J., 29-30 June 1998.
Stewart, P. and R. Langley (1998). "Atmospheric Investigations for WAAS – Ionosphere" Viewgraphs of presentation at the FAA Tech. Center, Atlantic City, N.J., 29-30 June 1998.
Collins, J.P. and R.B. Langley (1998). "The Residual Tropospheric Propagation Delay: How Bad Can It Get?" Proceedings of ION GPS-98, the 11th International Technical Meeting of the Satellite Division of The Institute of Navigation, Nashville, TN, U.S.A., 15-18 September 1998; pp. 729-738. (viewgraphs).
Stewart, P.J. and R.B. Langley (1998). "Ionospheric Modeling for WADGPS at Northern Latitudes." Proceedings of ION GPS-98, the 11th International Technical Meeting of the Satellite Division of The Institute of Navigation, Nashville, TN, U.S.A., 15-18 September 1998; pp. 757-765. (viewgraphs).
Collins, J.P., P.J. Stewart, and R.B. Langley (1998). "Multipath and Atmospheric Propagation Errors in Offshore Aviation DGPS Positioning." Viewgraphs presented at the 2nd Workshop on Offshore Aviation Research, Centre for Cold Ocean Resources Engineering, Memorial University of Newfoundland, St. John's, NF, 23-24 September 1998.

1999

Stewart, P.J. and R.B. Langley (1999). "Ionospheric Modelling for WADGPS at Northern Latitudes - Initial Results." Viewgraphs of paper presented at the URSI National Radio Science Meeting, Boulder, CO, U.S.A., 4 January 1999.
Langley, R.B. (1999). "1998: A Year of Innovation in (the) GPS World." Viewgraphs of a presentation at the Association of New Brunswick Land Surveyors Annual General Meeting, Fredericton, NB, 23 January 1999.
Collins, J.P. and R.B. Langley (1999). Possible Weighting Schemes for GPS Carrier Phase Observations in the Presence of Multipath. Contract report for the United States Army Corps of Engineers Topographic Engineering Center, No. DAAH04-96-C-0086 / TCN 98151, March.
Bisnath, S.B. and R.B. Langley (1999). A Comparison of the Kinematic GPS and Aerotriangulation Results Completed for the New Brunswick Colour Softcopy Orthophotomap Data Base Project. A study commissioned by WaterMark Industries Inc., Fredericton, N.B., March.
Bisnath, S.B. and R.B. Langley (1999). "Precise A Posteriori Geometric Tracking of Low Earth Orbiters with GPS." Canadian Aeronautics and Space Journal, Vol. 45, No. 3, pp. 245-252.
Stewart, P. and R.B. Langley (1999). "The Statistics of Scintillation Occurrence at GPS Frequencies." Proceedings of IES99, Ionospheric Effects Symposium, Alexandria, VA, U.S.A., 4-6 May 1999; pp. 122-131.
Langley, R.B. and P.J. Stewart (1999). "Mitigating the Effects of Space Weather on the Canadian WAAS." Viewgraphs of paper presented in Session JSG28, "Probing the Atmosphere by GPS", IUGG99, 22nd General Assembly of the International Union of Geodesy and Geophysics, Birmingham, England, 19-30 July 1999.
Kim, D. and R.B. Langley (1999). "An Optimized Least-Squares Technique for Improving Ambiguity Resolution and Computational Efficiency." Proceedings of ION GPS-99, the 12th International Technical Meeting of the Satellite Division of The Institute of Navigation, Nashville, TN, U.S.A., 14-17 September 1999; pp. 1579-1588.
Kim, D. and R.B. Langley (1999). "A Search Space Optimization Technique for Improving Ambiguity Resolution and Computational Efficiency." Paper presented at GPS99, International Symposium on GPS: Application to Earth Sciences and Interaction with Other Space Geodetic Techniques, Tsukuba, Japan, 18-22 October 1999. A slightly revised version was published in Earth, Planets and Space, Vol. 52 (2000), pp. 807-812.

2000

Mendes, V.B., G. Prates, L. Santos, and R.B. Langley (2000). "An Evaluation of Models for the Determination of the Weighted Mean Temperature of the Atmosphere." Proceedings of The Institute of Navigation 2000 National Technical Meeting, Anaheim, CA, U.S.A., 26-28 January 2000; pp. 433-438.
Bisnath, S.B. and R.B. Langley (2000). "Automated Cycle-slip Correction of Dual-frequency Kinematic GPS Data." Proceedings of the 47th Annual Conference of the Canadian Aeronautics and Space Institute, Ottawa, 30 April - 3 May 2000; pp. 121-125.
Kim, D. and R.B. Langley (2000). "The Multipath Divergence Problem in GPS Carrier-smoothed Pseudorange." Proceedings of the 47th Annual Conference of the Canadian Aeronautics and Space Institute, Ottawa, 30 April - 3 May 2000; pp. 161-163.
Kim, D. and R.B. Langley (2000). "GPS Ambiguity Resolution for Long-baseline Kinematic Applications." Paper presented at the GEOIDE Second Annual Conference, Calgary, 25-26 May 2000.
Kim, D. and R.B. Langley (2000). "Kalman-filter-based GPS Ambiguity Resolution for Real-time Long-baseline Kinematic Applications." Proceedings of the 2nd International Workshop on "Satellite Navigation in CEI [Central European Initiative] Area", University of Warmia and Mazury in Olsztyn, Olsztyn, Poland, 3-5 July 2000; Reports on Geodesy, Institute of Geodesy and Geodetic Astronomy, Warsaw University of Technology, No. 9 (55), 2000; pp. 17-28.
Langley, R.B., H. Jannasch, B. Peeters, and S. Bisnath (2000). "The GPS Broadcast Orbits: An Accuracy Analysis." Viewgraphs of paper presented in Session B2.1-PSD1, "New Trends in Space Geodesy", 33rd COSPAR Scientific Assembly, Warsaw, 16-23 July 2000.
Bisnath, S.B. (2000). "Efficient, Automated Cycle-slip Correction of Dual-frequency Kinematic GPS Data." Proceedings of ION GPS 2000, the 13th International Technical Meeting of The Institute of Navigation, Salt Lake City, Utah, 19-22 September 2000; pp. 145-154.
Kim, D. and R.B. Langley (2000). "A Reliable Approach for Ambiguity Resolution in Real-time Long-baseline Kinematic GPS Applications." Proceedings of ION GPS 2000, 13th International Technical Meeting of the Satellite Division of The Institute of Navigation, Salt Lake City, UT, 19-22 September 2000; pp. 1081-1091.
Kim, D. and R.B. Langley (2000). "GPS Ambiguity Resolution and Validation: Methodologies, Trends and Issues." Proceedings of the 7th GNSS Workshop - International Symposium on GPS/GNSS, Seoul, Korea, 30 November - 2 December 2000, Tutorial/Domestic Session, pp. 213-221.

2001

Bisnath, S.B. and R.B. Langley (2001). "Precise Orbit Determination of Low Earth Orbiters with GPS Point Positioning." Proceedings of The Institute of Navigation 2001 National Technical Meeting, Long Beach, CA, U.S.A., 22-24 January 2001; pp. 725-733.
Kim, D. and R.B. Langley (2001). "Estimation of the Stochastic Model for Long-Baseline Kinematic GPS Applications." Proceedings of The Institute of Navigation 2001 National Technical Meeting, Long Beach, CA, U.S.A., 22-24 January 2001; pp. 586-595.
Langley, R.B. (2001). "GPS and E-911: An Update on the Technology." Viewgraphs of invited keynote presentation to the NB 9-1-1 Service Stakeholders Forum, Fredericton, N.B., 30 January 2001.
Bisnath, S.B. and R.B. Langley (2001). "GPS Phase-connected, Precise Point Positioning of Low Earth Orbiters." Presented at GNSS 2001, Sevilla, Spain, 8-11 May 2001. (Omitted from proceedings in error.)
Kim, D. and R.B. Langley (2001). "Instantaneous Real-time Cycle-slip Correction of Dual-frequency GPS Data." Proceedings of KIS2001, International Symposium on Kinematic Systems in Geodesy, Geomatics and Navigation, Banff, 5-8 June 2001; pp. 255-264.
Bisnath, S.B. and R.B. Langley (2001). "Pseudorange Multipath Mitigation by Means of Multipath Monitoring and De-weighting." Proceedings of KIS2001, International Symposium on Kinematic Systems in Geodesy, Geomatics and Navigation, Banff, 5-8 June 2001; pp. 392-400.
Beran, T., S.B. Bisnath, and R.B. Langley (2001). "Single Receiver GPS Positioning in Support of Airborne Gravity for Exploration and Mapping." Poster presented at the GEOIDE 3rd Annual Conference, Fredericton, 20-22 June 2001.
Kim, D. and R.B. Langley (2001). "Stochastic Modelling and Quality Control for Real-time Long-baseline Kinematic GPS Applications." Poster presented at the GEOIDE 3rd Annual Conference, Fredericton, 20-22 June 2001.
Langley, R.B. (2001). "The Global Positioning System: Past, Present, and Future." Viewgraphs of invited presentation at The Future of Geodesy and Geomatics Research and Education Forum, held in celebration of the 40th anniversary of the Department of Geodesy and Geomatics Engineering, Fredericton, 23 June 2001.
Bisnath, S.B. and R.B. Langley (2001). "A New Technique for GPS-based Orbit Determination of Geoscience Spacecraft." Proceedings of Digital Earth 2001, Fredericton, N.B., 24-28 June 2001.
Shen, C. and R.B. Langley (2001). "Processing of GPS Data from a Regional Continuous Monitoring Network." Poster presented at the GEOIDE 3rd Annual Conference, Fredericton, 20-22 June 2001.
Langley, R.B. (2001). "Satellite Navigation: GPS Modernization and R&D in the Academic Sector." Viewgraphs of invited presentation to the National Sector Team for Space Annual Meeting, Canadian Space Agency, St-Hubert, QC, 3-4 July 2001.
Bisnath, S.B. and R.B. Langley (2001). "High-Precision Platform Positioning with a Single GPS Receiver." Proceedings of ION GPS 2001, 14th International Technical Meeting of the Satellite Division of The Institute of Navigation, Salt Lake City, UT, 11-14 September 2001; pp. 2585-2593. An edited version of this paper entitled "High-Precision, Kinematic Positioning with a Single GPS Receiver" appeared in Navigation, Journal of The Institue of Navigation, Vol. 49, No. 3, Fall 2002, pp. 161-169.
Fedrizzi, M., I.J. Kantor, E. Rodrigues de Paula, R.B. Langley, M.C. Santos, and A. Komjathy (2001). "The Low-Latitude Ionosphere: Monitoring its Behaviour with GPS." Proceedings of ION GPS 2001, 14th International Technical Meeting of the Satellite Division of The Institute of Navigation, Salt Lake City, UT, 11-14 September 2001; pp. 2468-2475. (Best presentation in session award)
Kim, D. and R.B. Langley (2001). "Mitigation of GPS Carrier Phase Multipath Effects in Real-Time Kinematic Applications." Proceedings of ION GPS 2001, 14th International Technical Meeting of the Satellite Division of The Institute of Navigation, Salt Lake City, UT, 11-14 September 2001; pp. 2144-2152.
Ueno, M. K. Hoshinoo, K. Matsunaga, M. Kawai, H. Nakao, and R.B. Langley (2001). "Assessment of Atmospheric Delay Correction Models for the Japanese MSAS." Proceedings of ION GPS 2001, 14th International Technical Meeting of the Satellite Division of The Institute of Navigation, Salt Lake City, UT, 11-14 September 2001; pp. 2341-2350.
Kim, D. and R.B. Langley (2001). "Instantaneous Real-time Cycle-slip Correction for Quality Control of GPS Carrier-phase Measurements." A final version of this paper has been published in Navigation, Journal of The Institute of Navigation, Vol. 49, No. 4, Winter 2002-2003, pp. 205-222.
Kim, D. and R.B. Langley (2001). "Quality Control Techniques and Issues in GPS Applications: Stochastic Modelling and Reliability Testing." Invited presentation at 2001 International Symposium on GPS/GNSS, Jeju, Korea, 7-9 November 2001; Proceedings of Tutorial and Domestic Session, pp. 76-85.

2002

Mendes, V.B., G. Prates, E.C. Pavlis, D.E. Pavlis, and R.B. Langley (2002). "Improved Mapping Functions for Atmospheric Refraction Correction in SLR." Geophysical Research Letters, Vol. 29, No. 10, pp. 53-1 - 53-4.
Bisnath, S.B. and R.B. Langley (2002). "CHAMP Orbit Determination with GPS Phase-Connected, Precise Point Positioning. Proceedings of the First CHAMP Science Meeting, Potsdam, Germany, 22-25 January 2002; pp. 59-64.
Langley, R.B. (2002). "Monitoring the Ionosphere and Neutral Atmosphere with GPS." Viewgraphs of invited presentation to the Canadian Association of Physicists Division of Atmospheric and Space Physics Workshop, Fredericton, N.B., 21-23 February 2002.
Mendes, V.B. and R.B. Langley (2002). "Revised Refractive Index Formulae and Their Effect in Zenith Delay Prediction and Estimation." Viewgraphs of paper presented in Session D2, "GPS for Predictions of Weather and Atmospheric Effects," at IEEE PLANS 2002, Palm Springs, CA, 15-18 April 2002.
Rho, H. and R.B. Langley (2002). "Assessment of WAAS Correction Data in Eastern Canada." Proceedings of Ionospheric Effects Symposium, IES2002, Alexandria, Virginia, 7-9 May 2002; pp. 131-138.
Beran, T., D. Kim, and R.B. Langley (2002). "Multipath Filtering in the Spaceborne Environment: Simulation Study." Poster presented at the GEOIDE 4th Annual Conference, Toronto, Ontario, 22-24 May 2002.
Horvath, T, R.B. Langley, K. MacLeod, and K. Lochhead (2002). "Real-Time Internet-Based GPS·C Tests at the University of New Brunswick." Poster presented at GNSS 2002, Copenhagen, Denmark, 27-30 May 2002.
Bisnath, S.B. and R.B. Langley (2002). "Precise Orbit Determination of the CHAMP Satellite with Stand-alone GPS." Viewgraphs of paper presented at GNSS 2002, Copenhagen, Denmark, 27-30 May 2002.
Kim, D. and R.B. Langley (2002). "On Ultrahigh-Precision GPS Positioning and Navigation." Proceedings of ION GPS 2002, 15th International Technical Meeting of the Satellite Division of The Institute of Navigation, Portland, OR, 24-27 September 2002; pp. 904-913. An edited and updated version of this paper appearded in Navigation, Journal of The Institute of Navigation, Vol. 50, No. 2, Summer 2003, pp. 103-116.

2003

Kim, D. and R.B. Langley (2003). "Ultrahigh-precision GPS Applications Using Real-time Kinematic Technology." Summary viewgraphs for poster presented at the EGS-AGU-EUG Joint Assembly, Nice, 6-11 April 2003. Abstract published in Geophysical Research Abstracts, Vol. 5, 06331, 2003.
Ueno, M., K. Itani, and R.B. Langley (2003). "Real-time GPS Landslide Monitoring under Poor Satellite Visibility." Poster presented at the EGS-AGU-EUG Joint Assembly, Nice, 6-11 April 2003. Abstract published in Geophysical Research Abstracts, Vol. 5, 01931, 2003.
Kim, D., R.B. Langley,J-H Kim, and S-N Kim (2003). "A Gantry Crane Auto-Steering System Based on GPS RTK Technology." Proceedings of GNSS 2003, Graz, 22-25 April 2003.
Kim, D., R.B. Langley, and J. Bond, and A. Chrzanowski (2003). "Local Deformation Monitoring Using Real-time GPS Kinematic Technology: Initial Study." Viewgraphs of paper presented at IUGG 2003, Sapporo, 2 July 2003. Paper published as "Local Deformation Monitoring Using GPS in an Open Pit Mine: Initial Study", GPS Solutions, Vol. 7, No. 3, 2003, pp. 176-185.
R.B. Langley, H. Rho, and A. Kassam (2003). "The Canada-wide Differential GPS Service: Initial Test Results." Viewgraphs of paper presented at IUGG 2003, Sapporo, 3 July 2003.
M. Fedrizzi, E.R. de Paula, and R.B. Langley (2003). "Monitoring the Response to Geomagnetic Storms Using GPS Total Electron Content Measurements." Viewgraphs of paper presented at IUGG 2003, Sapporo, 3 July 2003.
Bond, J., D. Kim, R.B. Langley and A. Chrzanowski (2003). "An Investigation on the Use of GPS for Deformation Monitoring in Open Pit Mines. " Proceedings of CAMI 2003, the 4th International Conference on Computer Applications in the Minerals Industries, Calgary, Alberta, 8-10 September 2003.
T. Beran, D. Kim, and R.B. Langley (2003). "High-Precision Single-Frequency GPS Point Positioning." Proceedings of ION GPS/GNSS 2003, 16th International Technical Meeting of the Satellite Division of The Institute of Navigation, Portland, OR, 9-12 September 2003; pp. 1192-1200.
Guo., J. and R.B. Langley (2003). "A New Tropospheric Propagation Delay Mapping Function for Elevation Angles Down to 2°." Proceedings of ION GPS/GNSS 2003, 16th International Technical Meeting of the Satellite Division of The Institute of Navigation, Portland, OR, 9-12 September 2003; pp. 386-376.
Kim, D. and R.B. Langley (2003). "A New Dual-Mode GPS Real-Time Kinematic System for Seamless Ultahigh-Precision Positioning and Navigation." Proceedings of ION GPS/GNSS 2003, 16th International Technical Meeting of the Satellite Division of The Institute of Navigation, Portland, OR, 9-12 September 2003; pp. 2120-2128.
Rho, H., R.B. Langley, and A. Kassam (2003). "The Canada-Wide Differential GPS Service: Initial Performance." Proceedings of ION GPS/GNSS 2003, 16th International Technical Meeting of the Satellite Division of The Institute of Navigation, Portland, OR, 9-12 September 2003; pp. 425-436. High resolution version (page 6 replaced with vector-based figures).
Ueno, M., K. Itani, and R.B. Langley (2003). "Real-Time GPS Landslide Monitoring Under Poor Satellite Visibility." Proceedings of 2003 International Symposium on GPS/GNSS, Tokyo, Japan, 15-18 November 2003; pp. 515-522

2004

Serrano, L., D. Kim, and R.B. Langley (2004). "A GPS Velocity Sensor: How Accurate Can It Be? – A First Look." Proceedings of NTM 2004, the 2004 National Technical Meeting of The Institute of Navigation, San Diego, CA, 26-28 January 2004; pp. 875-885.

Fedrizzi, M., E.R. de Paula, R.B. Langley, A. Komjathy, I.J. Kantor, and I.S. Batista (2004). "Study of the March 31, 2001 Magnetic Storm Effects on the Ionosphere Using GPS Data." This paper was presented as "Study of Magnetic Storm Effects on the Ionosphere Using GPS Data" at the 35th COSPAR Scientific Assembly, Paris, 18-25 July 2004. Advances in Space Research, Vol. 36, pp. 534-545.

Rho, H. and R.B. Langley (2004). "An Enhanced UNB Ionospheric Modeling Technique for SBAS: the Quadratic Approach." Proceedings of ION GNSS 2004, 17th International Technical Meeting of The Institute of Navigation, Long Beach, CA, 21-24 September 2004; pp. 354-365.

Kim, D., S. Bisnath, R.B. Langley, and P. Dare (2004). "Performance of Long-Baseline Real-Time Kinematic Applications by Improving Tropospheric Delay Modeling." Proceedings of ION GNSS 2004, 17th International Technical Meeting of The Institute of Navigation, Long Beach, CA, 21-24 September 2004; pp. 1414-1422.

Beran, T., S.B. Bisnath, and R.B. Langley (2004). "Evaluation of High-Precision, Single-Frequency GPS Point Positioning Models." Proceedings of ION GNSS 2004, 17th International Technical Meeting of The Institute of Navigation, Long Beach, CA, 21-24 September 2004; pp. 1893-1901.

Serrano, L., D. Kim, and R.B. Langley (2004). "A Single GPS Receiver as a Real-Time, Accurate Velocity and Acceleration Sensor." Proceedings of ION GNSS 2004, 17th International Technical Meeting of The Institute of Navigation, Long Beach, CA, 21-24 September 2004; pp. 2021-2034.

Fedrizzi,M., E.R. de Paula, I.J. Kantor, R.B. Langley, A. Komjathy, E.A. Araujo-Pradere, and T.J. Fuller-Rowell (2004). "Ionospheric Response to Severe Magnetic Storms Using GPS Total Electron Content Measurements." Proceedings of the International Beacon Satellite Symposium 2004, Trieste, Italy, 18-22 October 2004.

Langley, R.B., O. Montenbruck, M. Markgraf, and D. Kim (2004). "Qualification of a Commercial Dual-Frequency GPS Receiver for the e-POP Platform onboard the Canadian CASSIOPE Spacecraft." Proceedings of NAVITEC '2004, the 2nd ESA Workshop on Satellite Navigation User Equipment Technologies, ESTEC, Noorwijk, The Netherlands, 8-10 December 2004; pp. 397-405.

2005

Kim, D. and R.B. Langley (2005). "Nullification of Differential Ionospheric Delay for Long-Baseline Real-Time Kinematic Applications." Proceedings of the 61st Annual Meeting of The Institute of Navigation, Cambridge, MA, 27-29 June 2005; pp. 949-960. An edited and updated version of this paper will appear in Navigation, Journal of The Institute of Navigation.

Serrano, L., D. Kim, and R.B. Langley (2005). "A New Carrier-Phase Multipath Observable for GPS Real-Time Kinematics Based on Between Receiver Dynamics." Proceedings of the 61st Annual Meeting of The Institute of Navigation, Cambridge, MA, 27-29 June 2005; pp. 1105-1115.

Rho, H. and R.B. Langley (2005). "Ionospheric Modeling with the Quadratic Approach: Results for the Super Storms" (viewgraphs). Proceedings of the 61st Annual Meeting of The Institute of Navigation, Cambridge, MA, 27-29 June 2005; pp. 334-350.

Serrano, L., D. Kim, and R.B. Langley (2005). "A New Approach for Mitigating Low-Frequency Carrier-Phase Multipath in GPS-RTK, Based on Between-Receivers Dynamics and an Effective Reflector." Proceedings of ION GNSS 2005, 18th International Technical Meeting of The Institute of Navigation, Long Beach, CA, 13-16 September 2005; pp. 94-103.

Kim, D., L. Serrano, and R.B. Langley (2005). "Compensation of the Effects of Phase Wind-up for Improving the Performance of a GPS RTK-Based Vehicle Navigation System." Proceedings of ION GNSS 2005, 18th International Technical Meeting of The Institute of Navigation, Long Beach, CA, 13-16 September 2005; pp. 346-354.

Rho, H. and R.B. Langley (2005). "SBAS Ionospheric Modeling with the Quadratic Approach: Reducing the Risks." Proceedings of ION GNSS 2005, 18th International Technical Meeting of The Institute of Navigation, Long Beach, CA, 13-16 September 2005; pp. 723-734.

Rho, H. and R.B. Langley (2005). "Dual-frequency GPS Precise Point Positioning with WADGPS Corrections." Proceedings of ION GNSS 2005, 18th International Technical Meeting of The Institute of Navigation, Long Beach, CA, 13-16 September 2005; pp. 1470-1482. An edited and updated version of this paper appeared in Navigation, Journal of The Institute of Navigation, Vol. 54, No. 2, Summer 2007; pp. 139-152.

Beran, T., R.B. Langley, S.B. Bisnath, and L. Serrano (2005). "High-Accuracy Point Positioning with Low-Cost GPS Receivers: How Good Can It Get?" Proceedings of ION GNSS 2005, 18th International Technical Meeting of The Institute of Navigation, Long Beach, CA, 13-16 September 2005; pp. 1524-1534. (Best presentation in session award) An edited and updated version of this paper appearded in Navigation, Journal of The Institute of Navigation, Vol. 54, No. 1, Spring 2007, pp. 53-63.

Larocca, A.P.C., R.E. Schaal, M.C. Santos, R.B. Langley, and D. Kim (2005). "Dynamic Monitoring of Structures at the Millimeter Level: GPS versus Displacement Transducers and Accelerometers Ð A Summary." Proceedings of ION GNSS 2005, 18th International Technical Meeting of The Institute of Navigation, Long Beach, CA, 13-16 September 2005; pp. 1957-1960.

Larocca, A.P.C., R.E. Schaal, M.C. Santos, R.B. Langley (2005). "Monitoring the Deflection of the Pierre-Laporte Suspension Bridge with the Phase Residual Method." Proceedings of ION GNSS 2005, 18th International Technical Meeting of The Institute of Navigation, Long Beach, CA, 13-16 September 2005; pp. 2023-2028.

Ahn, Y.W., D. Kim, P. Dare, and R.B. Langley (2005). "Long Baseline GPS RTK Performance in a Marine Environment using NWP Ray-Tracing Technique under Varying Troposphere Conditions." Proceedings of ION GNSS 2005, 18th International Technical Meeting of The Institute of Navigation, Long Beach, CA, 13-16 September 2005; pp. 2092-2103.

James, H.G., P.A. Bernhardt, R.B. Langley, C.L. Siefring, and A.W. Yau (2005). "Radio-Frequency Experiments with the Enhanced Polar Outflow Probe Satellite Payload Using Its RRI, GAP, and CERTO Instruments." Proceedings of URSI GA 2005, the 28th General Assembly of the International Union of Radio Science, New Delhi, India, 23-29 October 2005; On line .

2006

Leandro, R., M. Santos, and R.B. Langley (2006). "UNB Neutral Atmosphere Models: Development and Performance." Proceedings of ION NTM 2006, the 2006 National Technical Meeting of The Institute of Navigation, Monterey, CA, 18-20 January 2006; pp. 564-573.

Lawrence, D., R.B. Langley, D. Kim, F.-C. Chan, and B. Pervan (2006). "Decorrelation of Troposphere Across Short Baselines." Proceedings of IEEE/PLANS 2006, San Diego, CA, 24-27 April 2006; pp. 97-102. (Best paper in track award)

Ward, W.E., D. Degenstein, R. Langley, R.P. Lowe, A. Manson, A. Bell, and G. Buttner (2006). "An Atmospheric Dynamics Mission for Investigating Dynamical Processes in the Middle Atmosphere." Proceedings of ASTRO 2006, the 13th Astronautics Conference of the Canadian Aeronautics and Space Institute, Montreal, 25-27 April 2006.

Kim, D., L. Serrano, and R.B. Langley (2006). "Phase Wind-Up Analysis: Assessing Real-Time Kinematic Performance." GPS World, September, Vol. 17., No. 9, pp. 58-64.

Serrano, L., D. Kim, and R.B. Langley (2006). "Near Real-Time Carrier-Phase Multipath Mitigation in Kinematic Applications, Using a Dual-Antenna System and Effective Close Range Reflectors." Proceedings of ION GNSS 2006, the 19th International Technical Meeting of the Satellite Division of The Institute of Navigation, Fort Worth, TX, 26-29 September 2006; pp. 863-872.

Larocca, A.P.C., R.E. Schaal, M.C. Santos, and R.B. Langley (2006). "Analyzing the Dynamic Behavior of Suspension Bridge Towers Using GPS." Proceedings of ION GNSS 2006, the 19th International Technical Meeting of the Satellite Division of The Institute of Navigation, Fort Worth, TX, 26-29 September 2006; pp. 1477-1486.

Leandro, R.F., M.C. Santos, and R.B. Langley (2006). "Wide Area Neutral Atmosphere Models for GNSS Applications." Proceedings of ION GNSS 2006, the 19th International Technical Meeting of the Satellite Division of The Institute of Navigation, Fort Worth, TX, 26-29 September 2006; pp. 1910-1924. (Best presentation in session award)

2007

Sükeová, L., M.C. Santos, R.B. Langley, and R.F. Leandro (2007). A Preliminary Report on L2C Data Collection and Analysis using a Trimble R7 GPS Receiver. January.

Leandro, R., R.B. Langley, and M.C. Santos (2007). "Estimation of P2-C2 Biases by Means of Precise Point Positioning." Proceedings of the 63rd Annual Meeting of The Institute of Navigation, Cambridge, MA, 23-25 April 2007; pp. 225-231.

Sükeová, L., M.C. Santos, R.B. Langley, R.F. Leandro, O. Nnani, and F. Nievinski (2007). "GPS L2C Signal Quality Analysis." Proceedings of the 63rd Annual Meeting of The Institute of Navigation, Cambridge, MA, 23-25 April 2007; pp. 232-241.

Kim, D. and R.B. Langley (2007). "GPS RTK-Based Attitude Determination for the e-POP Platform onboard the Canadian CASSIOPE Spacecraft in Low Earth Orbit." Proceedings of ENC-GNSS 07 (TimeNav'07), Geneva, Switzerland, 29 May - 1 June 2007; pp. 980-991.

Serrano, L., Kim, D., and R.B. Langley (2007). "Real-Time Multipath Calibration of a GPS-Based Heading Reference System." Proceedings of ENC-GNSS 07 (TimeNav'07), Geneva, Switzerland, 29 May - 1 June 2007; pp. 662-672.

Rho, H. and R.B. Langley (2007). "WAAS and CDGPS Performance on Ionospheric Storm Days Compared to Quiet Days." Proceedings of International Beacon Satellite Symposium, Boston, MA, 11-15 June 2007.

Leandro, R.F., R.B. Langley, and M. Santos (2007). "UNB3m_pack: A Neutral Atmosphere Delay Package for Radiometric Space Techniques." GPS Solutions; in press.