Bio


Juan Blanch is a senior research engineer in the Department of Aeronautics and Astronautics (AA) at Stanford University. He received a Ph.D. and M.S. in Aeronautics and Astronautics, and a M.S. in Electrical Engineering, all three from Stanford University. He is a graduate from Ecole Polytechnique, France.

Dr. Blanch’s research goal is to make location technology safe for critical applications, like air navigation and autonomous driving. His thesis work, for which he received the Institute of Navigation Parkinson Award, applied geospatial statistics to ionospheric estimation. This work is now fielded in the Wide Area Augmentation System – which is used by over 100,000 aircraft and by more than 1 million land users-, and has resulted in significant performance improvements. Within the FAA’s Global Navigation Satellite System Evolutionary Architecture Study (GEAS), Dr. Blanch developed an Advanced Receiver Autonomous Integrity Monitoring (ARAIM) algorithm that is now referenced by the international aviation integrity community. This algorithm can support a wide range of assumptions, readily handles multiple fault cases, and has a simple but rigorous proof of safety. He served as one of the lead authors on the initial GEAS report that proposed ARAIM as one of the most promising future architectures to support world-wide vertical guidance of aircraft, and he is now working on the development of the aviation standards to enable ARAIM. More recently, he has worked on the extension of these techniques to high accuracy automotive navigation.

He has over 100 scientific publications including conference proceedings, trade magazine articles, and peer-reviewed journal articles. He has been recognized as a top peer-reviewer by Publons and the Institute of Navigation, and is currently an Associate Editor for IEEE Transactions on Aerospace Electronic Systems. He received the 2010 Early Achievement Award from the Institute of Navigation.

Academic Appointments


  • Sr Research Engineer, Aeronautics and Astronautics

Honors & Awards


  • Top peer reviewer, Publons (2019)
  • Early Achievement Award, Institute of Navigation (June, 2010)
  • Bradford W. Parkinson Award for Graduate Student Excellence in Global Navigation Satellite Systems, Institute of Navigation (September 2004)

Boards, Advisory Committees, Professional Organizations


  • Associate Editor, IEEE (2018 - Present)
  • Member, Institute of Navigation (2003 - Present)

Professional Education


  • Ph.D., Stanford University, Aeronautics and Astronautics (2004)
  • M.S., Stanford University, Electrical Engineering (2004)
  • M.S., Stanford University, Aeronautics and Astronautics (2000)
  • Eng. Deg., Ecole Polytechnique, France, Applied Physics (1999)

Current Research and Scholarly Interests


My research focuses on the design of navigation integrity algorithms for safety critical applications (like air navigation and autonomous driving). I am interested in both the design of practical algorithms that provide the required safety margins, and in the theoretical limits on the performance of the integrity monitoring algorithms.

All Publications


  • Gaussian Bounds of Sample Distributions for Integrity Analysis IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS Blanch, J., Walter, T., Enge, P. 2019; 55 (4): 1806–15
  • Theoretical Results on the Optimal Detection Statistics for Autonomous Integrity Monitoring NAVIGATION-JOURNAL OF THE INSTITUTE OF NAVIGATION Blanch, J., Walter, T., Enge, P. 2017; 64 (1): 123–37

    View details for DOI 10.1002/navi.175

    View details for Web of Science ID 000403758600009

  • A Simple Position Estimator That Improves Advanced RAIM Performance IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS Blanch, J., Walter, T., Enge, P., Kropp, V. 2015; 51 (3): 2485-U960
  • Baseline Advanced RAIM User Algorithm and Possible Improvements IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS Blanch, J., Walker, T., Enge, P., Lee, Y., Pervan, B., Rippl, M., Spletter, A., Kropp, V. 2015; 51 (1): 713-732
  • Optimal Positioning for Advanced Raim NAVIGATION-JOURNAL OF THE INSTITUTE OF NAVIGATION Blanch, J., Walter, T., Enge, P. 2013; 60 (4): 279-289

    View details for DOI 10.1002/navi.49

    View details for Web of Science ID 000339567500003

  • RAIM with Optimal Integrity and Continuity Allocations Under Multiple Failures IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS Blanch, J., Walter, T., Enge, P. 2010; 46 (3): 1235-1247
  • WAAS and the Ionosphere - A Historical Perspective: Monitoring Storms NAVIGATION-JOURNAL OF THE INSTITUTE OF NAVIGATION Sparks, L., Altshuler, E., Pandya, N., Blanch, J., Walter, T. 2022; 69 (1)

    View details for DOI 10.33012/navi.503

    View details for Web of Science ID 000790870400004

  • Fast Protection Levels for Fault Detection With an Application to Advanced RAIM IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS Blanch, J., Walter, T. 2021; 57 (1): 55–65
  • GAUSSIAN BOUNDING IMPROVEMENTS AND AN ANALYSIS OF THE BIAS-SIGMA TRADEOFF FOR GNSS INTEGRITY Blanch, J., Liu, X., Walter, T., Inst Navigat INST NAVIGATION. 2021: 703-713
  • Continuity and Availability Evaluation in Horizontal ARAIM Joerger, M., Racelis, D., Blanch, J., Pervan, B., INST NAVIGAT INST NAVIGATION. 2021: 278-289
  • Analysis of GNSS Constellation Performance for Advanced RAIM Blanch, J., Liu, X., Gunning, K., Walter, T., INST NAVIGAT INST NAVIGATION. 2021: 1410-1434
  • Ground Monitoring to Support ARAIM for Military Users: Alternatives for Rapid and Rare Update Rates Pullen, S., Lo, S., Katz, A., Blanch, J., Walter, T., Katronick, A., Crews, M., Johnson, R., INST NAVIGAT INST NAVIGATION. 2021: 1481-1507
  • Providing Continuity and Integrity in the Presence of GNSS Spoofing Rothmaier, F., Chen, Y., Lo, S., Blanch, J., Walter, T., INST NAVIGAT INST NAVIGATION. 2021: 1828-1842
  • Investigation into September 2020 GPS SVN 74 Performance Anomaly Walter, T., Liu, Z., Blanch, J., Pham, K., Mick, J., Wanner, W., Inst Navigat INST NAVIGATION. 2021: 189-200
  • Assessment of Ionospheric Correction Behavior for Use with Precise Point Positioning (PPP) Walter, T., Blanch, J., de Groot, L., Norman, L., Inst Navigat INST NAVIGATION. 2021: 616-624
  • ARAIM for Military Users: ISM Parameters, Constellation-Check Procedure and Performance Estimates Katz, A., Pullen, S., Lo, S., Blanch, J., Walter, T., Katronick, A., Crews, M., Jackson, R., Inst Navigat INST NAVIGATION. 2021: 173-188
  • BOUNDING TEMPORALLY CORRELATED MEASUREMENT NOISE WITH AN APPLICATION TO GNSS INTEGRITY Blanch, J., Phelts, E., Gunning, K., Walter, T., de Groot, L., Norman, L., Inst Navigat INST NAVIGATION. 2020: 27-38
  • ARAIM Continuity and Availability Assertions, Assumptions, and Evaluation Methods Joerger, M., Zhai, Y., Martini, I., Blanch, J., Pervan, B., Inst Navigat INST NAVIGATION. 2020: 404–20
  • Determination of Fault Probabilities for ARAIM IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS Walter, T., Blanch, J., Gunning, K., Joerger, M., Pervan, B. 2019; 55 (6): 3505–16
  • Standards for ARAIM ISM Data Analysis Walter, T., Blanch, J., Gunning, K., Inst Navigat INST NAVIGATION. 2019: 777–84
  • Development of Advanced RAIM Minimum Operational Performance Standards Blanch, J., Walter, T., Berz, G., Burns, J., Clark, B., Joerger, M., Mabilleau, M., Martini, I., Milner, C., Pervan, B., Lee, Y., Inst Navigat INST NAVIGATION. 2019: 1381–91
  • Integrity for Tightly Coupled PPP and IMU Gunning, K., Blanch, J., Walter, T., de Groot, L., Norman, L., Inst Navigat INST NAVIGATION. 2019: 3066–78
  • SBAS Corrections for PPP Integrity with Solution Separation Gunning, K., Blanch, J., Walter, T., Inst Navigat INST NAVIGATION. 2019: 707–19
  • Development and Evaluation of Airborne Multipath Error Bounds for L1-L5 Blanch, J., Walter, T., Phelts, R., Inst Navigat INST NAVIGATION. 2019: 53–61
  • Reducing Computational Load in Solution Separation for Kalman Filters and an Application to PPP Integrity Blanch, J., Gunning, K., Walter, T., De Groot, L., Norman, L., Inst Navigat INST NAVIGATION. 2019: 720–29
  • Safety Analysis of Ranging Biases on the WAAS GEOs Walter, T., Blanch, J., Altshuler, E., Inst Navigat INST NAVIGATION. 2019: 113–30
  • Lower Bounds in Optimal Integrity Monitoring Blanch, J., Walter, T., Inst Navigat INST NAVIGATION. 2019: 915–24
  • Validation of the Unfaulted Error Bounds for ARAIM NAVIGATION-JOURNAL OF THE INSTITUTE OF NAVIGATION Walter, T., Gunning, K., Phelts, R., Blanch, J. 2018; 65 (1): 117–33
  • Improved User Position Monitor for WAAS NAVIGATION-JOURNAL OF THE INSTITUTE OF NAVIGATION Walter, T., Blanch, J. 2017; 64 (1): 165–75

    View details for DOI 10.1002/navi.180

    View details for Web of Science ID 000403758600012

  • Projected Performance of a Baseline High Integrity GNSS Railway Architecture under Nominal and Faulted Conditions Lo, S., Pullen, S., Blanch, J., Enge, P., Neri, A., Palma, V., Salvitti, M., Stallo, C., INST NAVIGAT INST NAVIGATION. 2017: 2148–71
  • Integrity measures in direct-positioning Closas, P., Gusi-Amigo, A., Blanch, J., INST NAVIGAT INST NAVIGATION. 2017: 2428–35
  • Feasibility of fault exclusion related to advanced RAIM for GNSS spoofing detection Kuusniemi, H., Blanch, J., Chen, Y., Lo, S., Innac, A., Ferrara, G., Honkala, S., Bhuiyan, M. H., Thombre, S., Soderholm, S., Walter, T., Phelts, R., Enge, P., INST NAVIGAT INST NAVIGATION. 2017: 2359–70
  • Initial Results of a Multi-Constellation ARAIM Airborne Prototype Blanch, J., Phelts, R., Chen, Y., Enge, P., INST NAVIGAT INST NAVIGATION. 2017: 184–209
  • A MATLAB Toolset to Determine Strict Gaussian Bounding Distributions of a Sample Distribution Blanch, J., Walter, T., Enge, P., INST NAVIGAT INST NAVIGATION. 2017: 4236–47
  • A Simple Satellite Exclusion Algorithm for Advanced RAIM Blanch, J., Walter, T., Enge, P., Inst Navigat INST NAVIGATION. 2016: 239–44
  • GNSS Integrity in The Arctic NAVIGATION-JOURNAL OF THE INSTITUTE OF NAVIGATION Reid, T., Walter, T., Blanch, J., Enge, P. 2016; 63 (4): 469-492
  • Improved Ephemeris Monitoring for GNSS Walter, T., Gunning, K., Blanch, J., Inst Navigat INST NAVIGATION. 2016: 600–608
  • Determination of Fault Probabilities for ARAIM Walter, T., Blanch, J., Joerger, M., Pervan, B., IEEE IEEE. 2016: 451–61
  • Improved User Position Monitor for WAAS Walter, T., Blanch, J., Inst Navigat INST NAVIGATION. 2016: 343–52
  • Mitigation of short duration satellite outages for Advanced RAIM and other integrity systems based on GNSS Blanch, J., Chen, Y., Phelts, R., Walter, T., Enge, P., Inst Navigat INST NAVIGATION. 2016: 1688–95
  • Demonstrating ARAIM on UAS using Software Defined Radio and Civilian Signal GPS L1/L2C and GLONASS G1/G2 Chen, Y., Perkins, A., Lo, S., Akos, D. M., Blanch, J., Walter, T., Enge, P., Inst Navigat INST NAVIGATION. 2016: 231–38
  • Satellite Selection for Multi-Constellation SBAS Walter, T., Blanch, J., Kropp, V., Inst Navigat INST NAVIGATION. 2016: 1350–59
  • ARAIM in Flight Using GPS and GLONASS: Initial Results from a Real-time Implementation Phelts, R., Blanch, J., Chen, Y., Enge, P., Riley, S., Inst Navigat INST NAVIGATION. 2016: 3264–69
  • Progress on Working Group-C Activities on Advanced RAIM Blanch, J., Walter, T., Enge, P., Burns, J., Alexander, K., Boyero, J., Lee, Y., Pervan, B., Joerger, M., Khanafseh, S., Rippl, M., Martini, I., Perea, S., Kropp, V., Macabiau, C., Suard, N., Berz, G., Inst Navigat INST NAVIGATION. 2015: 629–38
  • Airborne Mitigation Of Constellation Wide Faults Walter, T., Blanch, J., Inst Navigat INST NAVIGATION. 2015: 676–86
  • GNSS Integrity in The Arctic Reid, T. R., Walter, T., Blanch, J., Enge, P. K., Inst Navigat INST NAVIGATION. 2015: 1726–40
  • Fast Multiple Fault Exclusion with a Large Number of Measurements Blanch, J., Walter, T., Enge, P., Inst Navigat INST NAVIGATION. 2015: 696–701
  • Characterization of GPS Clock and Ephemeris Errors to Support ARAIM Walter, T., Blanch, J., Inst Navigat INST NAVIGATION. 2015: 920–31
  • The Effect of Nominal Signal Deformations on ARAIM Users International Technical Meeting of the Institute-of-Navigation Phelts, R. E., Blanch, J., Walter, T., Enge, P. INST NAVIGATION. 2014: 56–67
  • Reduced Subset Analysis for Multi-Constellation ARAIM International Technical Meeting of the Institute-of-Navigation Walter, T., Blanch, J., Enge, P. INST NAVIGATION. 2014: 89–98
  • Evaluation of a covariance-based clock and ephemeris error bounding algorithm for SBAS Blanch, J., Walter, T., Enge, P., Stern, A., Altshuler, E., Inst Navigat INST NAVIGATION. 2014: 3270–76
  • Exclusion for Advanced RAIM: Requirements and a Baseline Algorithm International Technical Meeting of the Institute-of-Navigation Blanch, J., Walter, T., Enge, P. INST NAVIGATION. 2014: 99–107
  • Architectures for Advanced RAIM: Offline and Online Blanch, J., Walter, T., Enge, P., Pervan, B., Joerger, M., Khanafseh, S., Burns, J., Alexander, K., Boyero, J., Lee, Y., Kropp, V., Milner, C., Macabiau, C., Suard, N., Berz, G., Rippl, M., Inst Navigat INST NAVIGATION. 2014: 787–804
  • Development of a Real-time GNSS Software Receiver for Evaluating RAIM in Multi-constellation International Technical Meeting of the Institute-of-Navigation Chen, Y., Lo, S., Akos, D. M., Choi, M., Blanch, J., Walter, T., Enge, P. INST NAVIGATION. 2014: 525–533
  • Critical Elements for a Multi-Constellation Advanced RAIM NAVIGATION-JOURNAL OF THE INSTITUTE OF NAVIGATION Blanch, J., Walter, T., Enge, P., Wallner, S., Fernandez, F. A., Dellago, R., Ioannides, R., Hernandez, I. F. 2013; 60 (1): 53-69

    View details for DOI 10.1002/navi.29

    View details for Web of Science ID 000339565800005

  • Incorporating GLONASS into Aviation RAIM Receivers International Technical Meeting of the Institute-of-Navigation Walter, T., Blanch, J., Choi, M. J., Reid, T., Enge, P. INST NAVIGATION. 2013: 239–249
  • Results on the Optimal Detection Statistic for Integrity Monitoring International Technical Meeting of the Institute-of-Navigation Blanch, J., Walter, T., Enge, P. INST NAVIGATION. 2013: 262–273
  • Near Term Improvements to WAAS Availability International Technical Meeting of the Institute-of-Navigation Blanch, J., Walter, T., Phelts, R. E., Enge, P. INST NAVIGATION. 2013: 71–77
  • Implementation of the L5 SBAS MOPS Walter, T., Blanch, J., Enge, P., Inst Navigat INST NAVIGATION. 2013: 814–24
  • Advanced RAIM System Architecture with a Long Latency Integrity Support Message Blanch, J., Walter, T., Enge, P., Inst Navigat INST NAVIGATION. 2013: 2605–13
  • A Framework for Analyzing Architectures that Support ARAIM 25th International Technical Meeting of the Satellite-Division of the Institute-of-Navigation Walter, T., Blanch, J., Enge, P. INST NAVIGATION. 2012: 2850–2857
  • Evolving WAAS to Serve L1/L5 Users NAVIGATION-JOURNAL OF THE INSTITUTE OF NAVIGATION Walter, T., Blanch, J., Phelts, R. E., Enge, P. 2012; 59 (4): 317-327

    View details for DOI 10.1002/navi.21

    View details for Web of Science ID 000209006500006

  • Evaluation of Multi-Constellation Advanced RAIM for Vertical Guidance using GPS and GLONASS Signals with Multiple Faults 25th International Technical Meeting of the Satellite-Division of the Institute-of-Navigation Choi, M., Blanch, J., Walter, T., Akos, D., Enge, P. INST NAVIGATION. 2012: 884–892
  • Advanced RAIM User Algorithm Description: Integrity Support Message Processing, Fault Detection, Exclusion, and Protection Level Calculation 25th International Technical Meeting of the Satellite-Division of the Institute-of-Navigation Blanch, J., Walter, T., Enge, P., Lee, Y., Pervan, B., Rippl, M., Spletter, A. INST NAVIGATION. 2012: 2828–2849
  • OPTIMAL POSITIONING FOR ADVANCED RAIM International Technical Meeting (ITM) of the Institute-of-Navigation (ION) Blanch, J., Walter, T., Enge, P. INST NAVIGATION. 2012: 1624–1631
  • L1/L5 SBAS MOPS to Support Multiple Constellations 25th International Technical Meeting of the Satellite-Division of the Institute-of-Navigation Walter, T., Blanch, J., Enge, P. INST NAVIGATION. 2012: 1287–1297
  • Estimating ionospheric delay using kriging: 2. Impact on satellite-based augmentation system availability RADIO SCIENCE Sparks, L., Blanch, J., Pandya, N. 2011; 46
  • Estimating ionospheric delay using kriging: 1. Methodology RADIO SCIENCE Sparks, L., Blanch, J., Pandya, N. 2011; 46
  • A Clock and Ephemeris Algorithm for Dual Frequency SBAS 24th International Technical Meeting of the Satellite Division of the Institute of Navigation (ION GNSS) Blanch, J., Walter, T., Enge, P. INST NAVIGATION. 2011: 2513–2519
  • Evolving WAAS to Serve L1/L5 Users 24th International Technical Meeting of the Satellite Division of the Institute of Navigation (ION GNSS) Walter, T., Blanch, J., Phelts, R. E., Enge, P. INST NAVIGATION. 2011: 2495–2504
  • Demonstrations of Multi-Constellation Advanced RAIM for Vertical Guidance using GPS and GLONASS Signals 24th International Technical Meeting of the Satellite Division of the Institute of Navigation (ION GNSS) Choi, M., Blanch, J., Akos, D., Heng, L., Gao, G., Walter, T., Enge, P. INST NAVIGATION. 2011: 3227–3234
  • A Proposal for Multi-Constellation Advanced RAIM for Vertical Guidance 24th International Technical Meeting of the Satellite Division of the Institute of Navigation (ION GNSS) Blanch, J., Walter, T., Enge, P., Wallner, S., Fernandez, F. A., Dellago, R., Ioannides, R., Pervan, B., Hernandez, I. F. INST NAVIGATION. 2011: 2665–2680
  • Advanced RAIM Demonstration using Four Months of Ground Data International Technical Meeting of the Institute of Navigation Choi, M., Blanch, J., Walter, T., Enge, P. INST NAVIGATION. 2011: 279–284
  • Optimization of a Vertical Protection Level Equation for Dual Frequency SBAS International Technical Meeting of the Institute of Navigation Blanch, J., Walter, T., Enge, P. INST NAVIGATION. 2011: 459–463
  • Coverage Improvement for Dual Frequency SBAS 2010 International Technical Meeting of the Institute-of-Navigation Walter, T., Blanch, J., Enge, P. INST NAVIGATION. 2010: 344–353
  • Kriging as a Means of Improving WAAS Availability Sparks, L., Blanch, J., Pandya, N., ION INST NAVIGATION. 2010: 2013–20
  • Prototyping Advanced RAIM for Vertical Guidance 23rd International Technical Meeting of the Satellite Division of the Institute-of-Navigation (ION GNSS-2010) Blanch, J., Choi, M. J., Walter, T., Enge, P. INST NAVIGATION. 2010: 285–291
  • GPS in Mid-life with an International Team of Doctors Analyzing IIF-1 Satellite Performance and Backward-Compatibility 23rd International Technical Meeting of the Satellite Division of the Institute-of-Navigation (ION GNSS-2010) Gao, G. X., Heng, L., Wong, G., Phelts, E., Blanch, J., Walter, T., Enge, P., Erker, S., Thoelert, S., Meurer, M. INST NAVIGATION. 2010: 1597–1604
  • Vertical Protection Level Equations for Dual Frequency SBAS 23rd International Technical Meeting of the Satellite Division of the Institute-of-Navigation (ION GNSS-2010) Walter, T., Blanch, J., Enge, P. INST NAVIGATION. 2010: 2031–2041
  • Evaluation of Signal in Space Error Bounds to Support Aviation Integrity 22nd International Technical Meeting of the Satellite Division of the Institute-of-Navigation (ION GNSS-09) Walter, T., Blanch, J., Enge, P. INST NAVIGATION. 2009: 1317–1329
  • Improved Iono PHMI Calculation for SBAS Systems Mayer, C., Blanch, J., ION INST NAVIGATION. 2009: 875–80
  • Hysteresis in RAIM 22nd International Technical Meeting of the Satellite Division of the Institute-of-Navigation (ION GNSS-09) Blanch, J., Mayer, C., Lo, S., Walter, T., Enge, P. INST NAVIGATION. 2009: 2818–2823
  • Methodology and Case Studies of Signal-in-Space Error Calculation Top-down Meets Bottom-up 22nd International Technical Meeting of the Satellite Division of the Institute-of-Navigation (ION GNSS-09) Gao, G. X., Tang, H., Blanch, J., Lee, J., Walter, T., Enge, P. INST NAVIGATION. 2009: 2824–2831
  • Worldwide Vertical Guidance of Aircraft Based on Modernized GPS and New Integrity Augmentations PROCEEDINGS OF THE IEEE Walter, T., Enge, P., Blanch, J., Pervan, B. 2008; 96 (12): 1918-1935
  • Bounding higher-order ionosphere errors for the dual-frequency GPS user RADIO SCIENCE Datta-Barua, S., Walter, T., Blanch, J., Enge, P. 2008; 43 (5)
  • Position Error Bound Calculation for GNSS using Measurement Residuals IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS Blanch, J., Walter, T., Enge, P. 2008; 44 (3): 977-984
  • Future Architectures to Provide Aviation Integrity 2008 National Technical Meeting of the Institute-of-Navigation Walter, T., Blanch, J., Enge, P., Pervan, B., Gratton, L. INST NAVIGATION. 2008: 394–401
  • Understanding PHMI for Safety of Life Applications in GNSS 2007 National Technical Meeting of the Institute-of-Navigation Blanch, J., Walter, T., Enge, P. INST NAVIGATION. 2007: 305–310
  • Fault Detection and Elimination for Galileo-GPS Vertical Guidance 2007 National Technical Meeting of the Institute-of-Navigation Ene, A., Blanch, J., Powell, J. D. INST NAVIGATION. 2007: 1244–1254
  • Galileo-GPS RAIM for Vertical Guidance 2006 National Technical Meeting of the Institute-of-Navigation Ene, A., Blanch, J., Walter, T. INST NAVIGATION. 2006: 432–440
  • Bounding Higher Order Ionosphere Errors for the Dual Frequency GPS User 19th International Technical Meeting of the Satellite Division of the Institute-of-Navigation Datta-Barua, S., Walter, T., Blanch, J., Enge, P. INST NAVIGATION. 2006: 1377–1392
  • Robust Detection of Ionospheric Irregularities NAVIGATION-JOURNAL OF THE INSTITUTE OF NAVIGATION Walter, T., et al 2001; 48 (2): 89–100