SAMUEL P. PULLEN
Office: Dept. of Aero/Astronautics Home: 3 Greenpark Way
Durand Bldg., Room 250 S. San Francisco, CA. 94080-7316
Stanford University (650) 871 - 4048
Stanford, CA. 94305-4035
(650) 723 - 8116
E-mail:
Most Recent Update: 28 August 2008
EDUCATION
Stanford University; Stanford, California
Ph.D., Aeronautics and Astronautics
Graduation Date: June 1996 GPA: 3.9/4.0
Thesis title: "Probabilistic Engineering Design Optimization: Applications to Spacecraft and
Navigation Systems"
M.S., Aeronautics and Astronautics
Graduation Date: June 1990 GPA: 3.8/4.0
Massachusetts Institute of Technology; Cambridge, Massachusetts
S.B., Aeronautics and Astronautics
S.B., History (emphasis on modern Europe, military strategy and development)
Graduation Date: June 1989 GPA: 4.8/5.0
WORK EXPERIENCE
Technical Manager/Senior Research Engineer, May 1999 – present (“Senior” since Sept. 2001)
Hansen Laboratories; Stanford University; Stanford, California
In addition to the research activities listed below, appointed as Manager of the Local Area Augmentation System (LAAS) research project, overseeing 10 – 15 engineers and graduate students working on algorithm research, prototype development, and test and validation. Taught graduate-level course, AA 279, "Space Mechanics", in Autumn Quarter 1999-2000. Provided support to other projects, including WAAS and JPALS.
Consultant, January 1996 – present
Activities (self-employed and as an employee of NavAstro, Los Gatos, CA.) include:
· Technical support of the Lockheed Martin GPS III Modernization effort under contract to the DOD GPS Joint Program Office, including requirements definition, civil augmentation system modeling, and performance simulation.
· Design and development of a unique method for onboard GPS satellite self-integrity monitoring based on the principles and algorithms developed for LAAS. A patent (USP 6,667,713; 12/23/03) resulted from this work.
· Technical support of the Johns Hopkins University Applied Physics Laboratory GPS Risk Assessment, including problem formulation, GPS/WAAS/LAAS performance simulation, and probabilistic risk analysis.
· Tutorial presentations on LAAS Fundamentals, Algorithms, and Aviation Applications.
· Space satellite and constellation reliability analysis, including pre-launch reliability estimates (using thesis research methodology) and revisions after observing initial behavior in orbit.
Research Associate, July 1996 – April 1999
Hansen Laboratories; Stanford University; Stanford, California
Responsible for risk-management activities for the Gravity Probe B spacecraft and experimental
payload. Implementing new reliability modeling and tracking techniques to better predict and
manage risk before and after commencement of the GP-B mission.
Responsible for safety monitoring and architecture development for the Local Area Augmentation System (LAAS)/Ground Based Augmentation System (GBAS) being developed by the FAA. This activity includes specification development, integrity verification, system optimization, and prototype hardware testing. Developed and tested a research prototype of the LAAS Ground Facility (LGF) that is used for derivation and validation of LGF requirements.
Responsible for Service Volume Modeling (SVM) of the Wide Area Augmentation System (WAAS)/Space Based Augmentation System (SBAS), including analyses of performance of prototype networks in India, South America, and Australia. Optimization of WAAS network elements for each application is based on SVM results.
Research Assistant, July 1991 - June 1996
Hansen Laboratories; Stanford University; Stanford, California
Thesis research in spacecraft design optimization. Numerical optimization procedure utilizes
global search to select optimal design given current uncertainty model and user priorities.
Research also included navigation and integrity algorithms for the Global Positioning System
(GPS) using similar optimization and evaluation techniques.
Engineering Research, June - August 1992 National Aerospace Laboratory; Chofu, Tokyo, Japan
Participated in U.S./Japanese research program (NSF Summer Institute). Supported work on HOPE space shuttle model identification and low-speed controller design. Developed and analyzed multi-model controller to compare with test performance of PID and LQR controllers.
Consulting/Research, on-site: June - December 1990, consultant: January 1991 – September 1997
The RAND Corporation; Santa Monica, California
Conducted research on the future structure of the U.S. Air Force. Performed statistical analysis
and generated model of future aircraft basing options. Created basing option cost analysis
software and published results for Department of Defense. Results of this study have been validated by subsequent USAF operational experience.
Engineering Staff, June - September 1988 The Dee Howard Company; San Antonio, Texas
Summer intern in structures/mass properties. Performed analyses and organized status reports for Airbus A310-304 interior modification project. Conducted product research to support detailed component analyses.
PUBLICATIONS
"A New Approach to GPS Integrity Monitoring using Prior Probability Models and Optimal
Threshold Search", Proceedings of IEEE PLANS '94, Las Vegas, NV., April 12-15, 1994.
"Simulation-Based Evaluation of WAAS Performance: Risk and Integrity Factors", Proceedings of ION GPS-94, Salt Lake City, UT., Sept. 20-23, 1994.
"System Design under Uncertainty: Evolutionary Optimization of the Gravity Probe-B Spacecraft", Proceedings of PPSN III, Jerusalem, Israel, October 9-14, 1994.
"A New Method for WAAS Coverage Prediction", Proceedings of ION Annual Meeting 1995, Colorado Springs, CO., June 5-7, 1995.
“Global Optimization of GPS Augmentation Architectures using Genetic Algorithms”, Proceedings of ION GPS-95, Palm Springs, CA., Sept. 12-15, 1995.
"Effects of Local Ionospheric Anomalies on Navigation Performance and Integrity Using WAAS", Proceedings of IEEE PLANS '96, Atlanta, GA., April 22-26, 1996.
"Wide Area Augmentation of the Global Positioning System", Proceedings of the IEEE. Vol. 84, No. 8, August 1996, pp. 1063-88.
“Study of WAAS Ionospheric Integrity”, Proceedings of ION GPS-96, Kansas City, MO., Sept. 17-20, 1996.
“A Comprehensive Integrity Verification Architecture for On-Airport LAAS Category III Precision Landing”, Proceedings of ION GPS-96, Kansas City, MO., Sept. 17-20, 1996.
“Control System Optimization with Unbounded Uncertainty: Application to Aircraft Precision Approach Using GPS”, Proceedings of IEEE CDC '96, Kobe, Japan, Dec. 11-13, 1996.
“Development, Implementation, and Testing of a Prototype LAAS Architecture”, Proceedings of GNSS 97, Munich, Germany, April 21-25, 1997.
“Optimal Augmentation of GPS using Inexpensive Geosynchronous Navigation Satellites”, Proceedings of ION GPS-97, Kansas City, MO., Sept. 16-19, 1997.
“Flight Test Evaluation of an Alternative Local Area Augmentation System Architecture”, Navigation: Journal of the Institute of Navigation. Vol. 45, No. 1, Spring 1998.
"A Multiple Hypothesis Approach to Satellite Navigation Integrity", Navigation: Journal of the Institute of Navigation. Vol. 45, No. 1, Spring 1998.
“Prototype LAAS Architecture Design Considerations”, GPS Solutions. Vol. 2, No. 1, Summer 1998.
“A Preliminary Study of the Effect of Ionospheric Scintillation on WAAS User Availability in Equatorial Regions”, Proceedings of ION GPS-98, Nashville, TN., Sept. 15-18, 1998.
"The Effects of Local Ionospheric Decorrelation on LAAS: Theory and Experimental Results," Proceedings of ION 1999 National Technical Meeting, San Diego, CA., Jan. 25-27, 1999.
GPS Risk Assessment Study: Final Report. Laurel, MD.: The Johns Hopkins University Applied Physics Laboratory, VS-99-007. January 1999.
“Interference Direction Finding for Aviation Applications of GPS,” Proceedings of ION GPS '99, Nashville, TN., Sept. 14-17, 1999.
“GPS Ephemeris Verification for Local Area Augmentation System (LAAS) Ground Stations”, Proceedings of ION GPS '99, Nashville, TN., Sept. 14-17, 1999.
“Precise Calibration of Pseudolite Positions in Indoor Navigation System," Proceedings of ION GPS '99, Nashville, TN., Sept. 14-17, 1999.
“GPS Risk Assessment for Civil Aviation”, Proceedings of ION GPS-99, Nashville, TN., Sept. 14-17, 1999.
"Development and Testing of the Stanford LAAS Ground Facility Prototype," Proceedings of ION 2000 National Technical Meeting, Anaheim, CA., Jan. 26-28, 2000.
"Signal Quality Monitoring: Test Results," Proceedings of ION 2000 National Technical Meeting, Anaheim, CA., Jan. 26-28, 2000.
"GPS-SPS Signal Quality Monitor," Proceedings of IEEE PLANS 2000, San Diego, CA., March 13-16, 2000.
"Practical Implementation Considerations in the Detection of GPS Satellite Signal Failures," Proceedings of IAIN World Congress/ION 56th Annual Meeting, San Diego, CA., June 26-28, 2000.
“GIDL: Generalized Interference Detection and Localization System," Proceedings of ION GPS 2000, Salt Lake City, UT., Sept. 19-22, 2000.
“Characterizing the Effect of Ionospheric Divergence and Decorrelation on LAAS," Proceedings of ION GPS 2000, Salt Lake City, UT., Sept. 19-22, 2000.
“A Real Time Signal Quality Monitor for GPS Augmentation Systems," Proceedings of ION GPS 2000, Salt Lake City, UT., Sept. 19-22, 2000.
“Interference to GPS from UWB Transmitters," Proceedings of ION GPS 2000, Salt Lake City, UT., Sept. 19-22, 2000.
“Development of Indoor Navigation System Using Pseudolites," Proceedings of ION GPS 2000, Salt Lake City, UT., Sept. 19-22, 2000.
“GBAS Validation Methodology and Test Results from the Stanford LAAS Integrity Monitor Testbed," Proceedings of ION GPS 2000, Salt Lake City, UT., Sept. 19-22, 2000.
“Development of the LAAS Accuracy Models," Proceedings of ION GPS 2000, Salt Lake City, UT., Sept. 19-22, 2000.
“Sigma Estimation, Inflation, and Monitoring in the LAAS Ground System," Proceedings of ION GPS 2000, Salt Lake City, UT., Sept. 19-22, 2000.
“Robust Signal Quality Monitoring and Detection of Evil Waveforms," Proceedings of ION GPS 2000, Salt Lake City, UT., Sept. 19-22, 2000.
“Integrity Design and Updated Test Results for the Stanford LAAS Integrity Monitor Testbed," Proceedings of the 57th ION Annual Meeting and the CIGTF 20th Biennial Guidance Test Symposium, Albuquerque, NM., June 11-13, 2001.
“LAAS Sigma-Mean Monitor Analysis and Failure-Test Verification," Proceedings of the 57th ION Annual Meeting and the CIGTF 20th Biennial Guidance Test Symposium, Albuquerque, NM., June 11-13, 2001.
"Ultra-Wideband and GPS: Can They Co-Exist?" GPS World. Vol. 12, No. 9, Sept. 2001, pp. 59-70.
“Testing and Research on Interference to GPS from UWB Transmitters," Proceedings of ION GPS 2001, Salt Lake City, UT., Sept. 11-24, 2001.
“Satellite Autonomous Integrity Monitoring and its Role in Enhancing GPS User Performance," Proceedings of ION GPS 2001, Salt Lake City, UT., Sept. 11-24, 2001.
“The Next Generation Integrity Monitor Testbed for Ground System Development and Validation Testing," Proceedings of ION GPS 2001, Salt Lake City, UT., Sept. 11-24, 2001.
"System Concepts For Cycle Ambiguity Resolution and Verification for Aircraft Carrier Landings," Proceedings of ION GPS 2001, Salt Lake City, UT., Sept. 11-24, 2001.
"Transient Performance Analysis of a Multicorrelator Signal Quality Monitor," Proceedings of ION GPS 2001, Salt Lake City, UT., Sept. 11-24, 2001.
"Ephemeris Protection Level Equations and Monitor Algorithms for GBAS," Proceedings of ION GPS 2001, Salt Lake City, UT., Sept. 11-24, 2001.
"Analysis of Reference Antenna Motion on the JPALS Shipboard Integrity Monitor," Proceedings of ION 2002 National Technical Meeting, San Diego, CA., Jan. 28-30, 2002.
"Using WAAS Ionospheric Data to Estimate LAAS Short Baseline Gradients," Proceedings of ION 2002 National Technical Meeting, San Diego, CA., Jan. 28-30, 2002.
“Assessment of Ionospheric Impact on LAAS Using WAAS Supertruth Data," Proceedings of the 58th ION Annual Meeting and the CIGTF 21st Biennial Guidance Test Symposium, Albuquerque, NM., June 24-26, 2002.
“Estimation of ICAO Threat Model Parameters for Operational GPS Satellites,” Proceedings of ION GPS 2002, Portland, OR., Sept. 24-27, 2002.
“Performance of the JPALS Shipboard Integrity Monitor,” Proceedings of ION GPS 2002, Portland, OR., Sept. 24-27, 2002.
“LAAS Ground Facility Design Improvements to Meet Proposed Requirements for Category II/III Operations,” Proceedings of ION GPS 2002, Portland, OR., Sept. 24-27, 2002.
“Integration of the Multipath Limiting Antenna with the LAAS Integrity Monitor Testbed,” Proceedings of ION GPS 2002, Portland, OR., Sept. 24-27, 2002.
“System Overview, Recent Developments, and Future Outlook for WAAS and LAAS,” Proceedings of Japan GPS Symposium 2002, Tokyo, Japan, Nov. 11-13, 2002.
“Strictly Positive Real H2 Controller Synthesis via Iterative Algorithms for Convex Optimization,” AIAA Journal of Guidance, Control, and Dynamics, Vol. 25, No. 6, Nov./Dec. 2002, pp. 1003-11.
"Radio Frequency Interference Validation Testing for LAAS Using the Stanford Integrity Monitor Testbed," Proceedings of ION 2003 National Technical Meeting, Anaheim, CA., Jan. 22-24, 2003.
"Airborne Autonomous Fault Detection for Shipboard Landing Navigation Using Carrier Phase DGPS," Proceedings of ION 2003 National Technical Meeting, Anaheim, CA., Jan. 22-24, 2003.
"Detecting Ionospheric Gradients with the Cumulative Sum (CUSUM) Method," Proceedings of 21st International Communication Satellite Systems Conference and Exhibit, Yokohama, Japan, AIAA 2003-2415, April 15-19, 2003.
"LAAS Position-Domain Monitor Analysis and Failure-Test Verification," Proceedings of 21st International Communication Satellite Systems Conference and Exhibit, Yokohama, Japan, AIAA 2003-2418, April 15-19, 2003.
“A More Complete and Updated Methodology for Assessing Intrasystem and Intersystem Interference for GPS and Galileo,” Proceedings of ION GPS/GNSS 2003, Portland, OR., Sept. 9-12, 2003.
“LAAS Ionosphere Spatial Gradient Threat Model and Impact of LGF and Airborne Monitoring,” Proceedings of ION GPS/GNSS 2003, Portland, OR., Sept. 9-12, 2003.
“CUSUM-Based Real-Time Risk Metrics for Augmented GPS and GNSS,” Proceedings of ION GPS/GNSS 2003, Portland, OR., Sept. 9-12, 2003.
“Doppler Aided Tracking Loops for SRGPS Integrity Monitoring,” Proceedings of ION GPS/GNSS 2003, Portland, OR., Sept. 9-12, 2003.
“SBAS/WAAS and GBAS/LAAS: Offline Simulation and Performance Prediction,” Proceedings of 2003 International Symposium on GPS/GNSS, Tokyo, Japan, Nov. 15-18, 2003.
"Effect of the Error in the Line-of-Sight Unit Vector on Pseudolite-Based Positioning Systems," Proceedings of ION 2004 National Technical Meeting, San Diego, CA., Jan. 26-28, 2004.
"Ionosphere Spatial Gradient Threat for LAAS: Mitigation and Tolerable Threat Space," Proceedings of ION 2004 National Technical Meeting, San Diego, CA., Jan. 26-28, 2004.
"Robust Airborne Navigation Algorithms for SRGPS," Proceedings of IEEE PLANS 2004, Monterey, CA., April 26-29, 2004.
"Orbit Ephemeris Monitors for Category I LAAS," Proceedings of IEEE PLANS 2004, Monterey, CA., April 26-29, 2004.
"Paired Overbounding and Application to GPS Augmentation," Proceedings of IEEE PLANS 2004, Monterey, CA., April 26-29, 2004.
“Performance Analysis and Experimental Validation of a Doppler-Aided GPS/INS Receiver for JPALS Applications,” Proceedings of ION GNSS 2004, Long Beach, CA., Sept. 21-24, 2004.
“Satellite Integrity Monitoring Concepts for GPS/Galileo Augmentation Systems,” Proceedings of ION GNSS 2004, Long Beach, CA., Sept. 21-24, 2004.
“Airborne Multipath Investigation via a GPS Software Receiver,” Proceedings of ION GNSS 2004, Long Beach, CA., Sept. 21-24, 2004.
“Experimental Observations and Integrity Monitor Applications of LAAS IMLA Carrier Phase Measurements,” Proceedings of ION GNSS 2004, Long Beach, CA., Sept. 21-24, 2004.
“Ionosphere Threat to LAAS: Updated Model, User Impact, and Mitigations,” Proceedings of ION GNSS 2004, Long Beach, CA., Sept. 21-24, 2004.