Graduate Exam Abstract

Dongyang Xu

Ph.D. Final
June 27, 2019, 1:30 pm - 3:30 pm
ECE Conference Room C101 B
On Equatorial Ionospheric Scintillation: Characterizing, Modeling, and Mitigation

Abstract: Ionospheric plasma irregularities along the propagation path of radio wave signals cause temporal fluctuations in signal phase and amplitude, which are referred to as ionospheric scintillation. Ionospheric scintillation most frequently occurs in equatorial and high latitude areas, while the strongest effects are often observed in equatorial areas during the post-sunset and pre-midnight period characterized with simultaneous deep amplitude fading and fast phase fluctuations. The scintillation effects can severely degrade receiver performance and impact a variety of GNSS applications. Four papers are presented that cover three different research aspects of the issue of equatorial ionospheric scintillation: characterization, modeling, and mitigation. The characterization of the ionospheric scintillation conducted in this thesis are statistical summaries obtained based on the processing results of real Ascension Island data, including the temporal characteristics of fast phase changes and deep fades, their correlation during concurrence, and the statistical relationship between the data bit decoding error occurrences and the intensity of amplitude scintillation. The modelling of ionospheric scintillation mainly deals with developing and using real data to validate a numerical mapping between ground observed scintillation indicators and an existing physics-based scintillation model parameters. The outcome of this work is a user-friendly scintillation signal simulator that can benefit the algorithm development community. The mitigation part presents evaluation results of three advanced scintillation signal tracking algorithms using the developed scintillation simulator.

Adviser: Dr. Jade Morton
Co-Adviser: N/A
Non-ECE Member: Dr. Olivier Pinaud, Math
Member 3: Dr. Charles Rino, ECE
Addional Members: Dr. Frank van Graas, ECE

Xu D., Morton Y. T, & Yang R. (2019). A Comparative Performance Analysis of Advanced GNSS Carrier Tracking Algorithms during Strong Equatorial Ionospheric Scintillation. To be submitted to IEEE TAES.

Xu D., Morton Y. T., Rino C. L., Carrano C. S., & Jiao Y (2019). A two-parameter GPS signal simulator for strong equatorial ionospheric scintillation: modeling and parameter characterization. Submitted to navigation.

Xu, D., Morton Y. T., Jiao Y., & Yang R. (2018). Implementation and performance evaluation of a vector-based receiver during strong equatorial scintillation on dynamic platforms,” Proc. ION GNSS+, Miami, FL.

Xu D. & Morton Y. T. (2018). GPS navigation data bit decoding error during strong equatorial scintillation. GPS Solutions. DOI: 10.1007/s10291-018-0775-1.

Xu D., Morton Y. T., Jiao Y., & Rino C. L. (2018). Simulation and tracking algorithm evaluation for scintillation signals on LEO satellites traveling inside the ionosphere. Proc. IEEE/ION PLANS, Monterey, CA.

Xu D. & Morton Y. T. (2017). Semi-open loop estimation of GPS carrier phase variations during deep amplitude fading of equatorial ionospheric scintillation. IEEE TAES. DOI: 10.1109/TAES.2017.2764778.

Xu D., Morton Y. T., Jiao Y., & Rino C. L. (2017). Robust GPS carrier tracking algorithms during strong equatorial scintillation for dynamic platforms. Proc. ION GNSS+, Portland, OR. Xu D., & Morton Y. T. (2016). Beidou signal parameters characterization during strong equatorial ionospheric scintillation. Proc. ION GNSS+, Portland, OR. (Invited)

Xu D., Morton Y. T., Akos D., Walter T. (2015). GPS multi-frequency carrier phase characterization during strong equatorial ionospheric scintillation. Proc. ION GNSS+, Tampa, FL.

Xu D., Morton Y. T. (2015). GPS carrier parameters characterization during strong equatorial ionospheric scintillation. Proc. ION ITM, Dana Point.

Xu D., Morton Y. T., Taylor S. (2014). Algorithms and results of tracking Beidou signals during strong ionospheric scintillation over Ascension Island. Proc. ION ITM, San Diego, CA.

Xu D., et al. (2012). Instantaneous cycle slip detection and repair for a standalone triple-frequency GPS receiver, Proc. ION GNSS, Portland, Oregon.

Xu D., et al. (2011). Dual-component Combined Tracking of GPS L5 Signals, SCIENTIA SINICA Physica, Mechanica & Astronomica 41.5 (2011): 653.

Yang R., Xu D., & Morton Y. T. (2019). Generalized multi-frequency GPS carrier tracking architecture: design and performance analysis. Submitted to IEEE Transactions on Aerospace and Electronic Systems (TAES).

Breitsch B., Xu D., Morton Y. T., & Rino C. (2019). GNSS carrier phase transitions due to ionosphere diffraction: simulation and characterization. Submitted to IEEE TAES.

Liu Z., Yang Z., Xu D., & Morton Y. T. (2019). On Inconsistent ROTI Derived From Multiconstellation GNSS Measurements of Globally Distributed GNSS Receivers for Ionospheric Irregularities Characterization. Radio Science. DOI: 10.1029/2018RS006596.

Han B., Morton Y. T., Gunawan E., &Xu D. (2019). Planetary Boundary Layer Height Detection Using Mountaintop-Based GNSS Radio Occultation Signal Amplitude. in IEEE Transactions on Geoscience and Remote Sensing. DOI: 10.1109/TGRS.2018.2890676.

Yang R., Xu D., & Morton Y. T. (2018). An improve adaptive multi-frequency GPS carrier tracking algorithm for navigation in challenging environments. Proc. IEEE/ION PLANS, Monterey, CA.

Jiao Y., Xu D., Rino C. L., Morton Y. T., & Carrano C. S. (2018). A multi-frequency GPS signal strong equatorial ionospheric scintillation simulator: algorithm, performance, and characterization. in IEEE TAES. DOI: 10.1109/TAES.2018.2805232.

Morton Y. T., Xu D., et al. (2017). Ionospheric scintillation observations in Singapore using a high gain antenna and SDR. Proc. Pacific PNT, Honolulu, HI.

Morton Y. T., Bourne H., Taylor S., Xu D., Yang R., van Graas F., &Pujara N. (2017). Mountain-top radio occultation with multi-GNSS signals: experiment and preliminary results. Proc. Pacific PNT, Honolulu, HI.

Collett I., Breitsch B., Xu D., &Morton Y. (2017). Statistical characterization of GNSS signal carrier Doppler frequency deviations during ionospheric scintillation. Int. Iono. Effects Sym., online

Jiao Y., Xu D., Morton Y., & Rino C. L. (2016). Equatorial scintillation amplitude fading characteristics across the GPS frequency bands. Navigation. DOI: 10.1002/navi.146.

Program of Study: